Geotechnical Engineering Construction Services Construction Materials Engineering Testing 3228 Halifax Street - Dallas, TX Ph FX.

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1 GEOTECHNICAL INVESTIGATION REHABILITATION OF SW CONSTRUCTION RD, 31 ST ST, 32 ND ST & 33 RD ST DFW AIRPORT, TEXAS AGG REPORT NO. DE18-047R3 FINAL SUBMITTAL OCTOBER 10, 2018 PREPARED FOR: DFW AIRPORT PRESENTED BY: Geotechnical Engineering Construction Services Construction Materials Engineering Testing 3228 Halifax Street - Dallas, TX Ph FX

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3 TABLE OF CONTENTS 1.0 INTRODUCTION 1 PAGE 1.1 PROJECT DESCRIPTION PURPOSE AND SCOPE FIELD INVESTIGATION LABORATORY TESTING SITE AND SUBSURFACE CONDITIONS GENERAL SITE CONDITIONS SUBSURFACE CONDITIONS SITE GEOLOGY GROUNDWATER CONDITIONS ANALYSIS AND SUBGRADE RECOMMENDATIONS SOIL MOVEMENTS OPTIONAL SITE MODIFICATION TO REDUCE SOIL MOVEMENTS EXISTING FILL SOILS PROOFROLLING AND FILL PLACEMENT SITE GRADING AND DRAINAGE PAVEMENT RECOMMENDATIONS PAVEMENT SECTIONS FOR 31 ST, 32 ND & 33 RD STREET PAVEMENT ANALYSES FOR SOUTHWEST CONSTRUCTION ROAD STABILIZATION WITH HYDRATED LIME CRUSHED STONE BASE RECOMPACTED SUBGRADE PAVEMENT CONSIDERATIONS TREE EFFECTS LIGHT POLE FOUNDATION RECOMMENDATIONS PIER RECOMMENDATIONS RESISTANCE OF LATERAL WINDS LOADS DRILLED SHAFT SOIL INDUCED UPLIFT LOADS DRILLED SHAFT CONSTRUCTION CONSIDERATIONS UTILITY REPAIR CONSIDERATIONS OPEN CUT EXCAVATIONS BRACING/SHORING CONSTRUCTION CONSIDERATIONS TRENCH BACKFILL FIELD SUPERVISION AND CONSTRUCTION TESTING LIMITATIONS ALLIANCE GEOTECHNICAL GROUP, INC DE18-047

4 FIGURES PLAN OF BORINGS LOGS OF BORINGS thru 16 LEGEND - KEY TO LOG TERMS & SYMBOLS SWELL TEST RESULTS SOLUBLE SULFATES TEST RESULTS LIME SERIES RESULTS MINIATURE HARVARD COMPACTION TEST RESULTS thru 25 RECOMMENDED SLOPE RATIOS FOR OPEN TRENCH CUTS DESIGN OF TRENCH BRACING LATERAL EARTH PRESSURE APPENDIX MEASURES TO MINIMIZE SHRINK/SWELL MOVEMENTS APPENDIX A PAVEMENT CORE SUMMARY & PICTURES APPENDIX B FOOD CATERING TRUCK & DFW EMPLOYEE BUS SPECIFICATIONS APPENDIX C PAVEMENT ANALYSES AND CALCULATION SUMMARY APPENDIX D ALLIANCE GEOTECHNICAL GROUP, INC DE18-047

5 GEOTECHNICAL INVESTIGATION REHAB SOUTHWEST CONSTRUCTION ROAD, 31 st ST, 32 nd ST & 33 rd STREET DALLAS FORT-WORTH INTERNATIONAL AIRPORT, TEXAS 1.0 INTRODUCTION 1.1 PROJECT DESCRIPTION The project consists of the rehabilitation of Southwest Construction Road, 31 st St, 32 nd St & 33 rd St at the Dallas Fort Worth International Airport. These roadways are distressed at various locations. The distress consists of lateral and longitudinal cracks, curb displacements, pavement settlements, spalling and potholes. It is understood that the travel lanes of 31 st, 32 nd and 33 rd Street will be replaced with new concrete pavements and that Southwest Construction Road will be replaced with new asphalt pavements. The shoulders of Southwest Construction Road will also be replaced with new asphalt sections. It is further understood that prior to the placement of the new pavements, various existing utility lines underneath the pavement will be repaired or replaced. In addition, new street light poles will be installed along the alignment 33 rd Street. Thirty-First Street is a two-lane undivided concrete roadway. There are asphalt overlays along the pavement edges in some areas. The asphalt overlays were placed to level the settled pavement. There are large trees with driplines extending over the pavement along the north and south curbs. Moisture absorption by the tree root systems is one key factor that has caused the pavement to settle due to ground shrinkage (caused by the tree root desiccation). Differential pavement movement and pavement cracks were observed along this alignment as seen in Photo 1. It is understood that this street is frequently used by taxis that queue at the east end of the street. PHOTO 1 DIFFERENTIAL PAVEMENT MOVEMENT ON 31 st STREET ALLIANCE GEOTECHNICAL GROUP DE PAGE 1

6 Thirty-Second Street is a four-lane divided concrete roadway. There are large trees in the median and behind the north and south curbs with driplines extending over the pavement. There is a section at the east end of this alignment where asphalt was placed to level the settled pavement. Moisture absorptions by the tree root systems is one key factor that has caused the pavement to settle due to ground shrinkage (caused by tree root desiccation). Another key factor that has likely contributed to the pavement settlement is the consolidation of non-compact backfill for the existing utility line beneath this area. Pavement cracks and curb displacements were observed along this street as seen in Photos 2 & 3. This street was observed to be used by automobiles accessing the US Post Office at the west end of 32 nd St and used by food catering trucks coming from the Southbound Service Road and 22 nd Ave. PHOTOS 2 & 3 CURB DISPLACEMENT AND PAVEMENT CRACKS ON 32 nd STREET Thirty-Third Street is a four-lane divided concrete roadway. There are large trees in the median and behind the north and south curbs with driplines extending over the pavement along the east portion of this street. The east end of this street is in poor condition and contains various pavement cracks, curb displacement and pavement settlements as seen in Photos 4 & 5. The east end of 33 rd St is closed off due to the severely distressed pavement condition. Based on field observations, the leading cause of the pavement settlement is the consolidation of non-compact backfill for the existing utility line beneath this area. There were several potholes observed along this street that were patched with asphalt. This street was observed to be used by automobiles, by food catering trucks and by DFW employee buses. ALLIANCE GEOTECHNICAL GROUP DE PAGE 2

7 PHOTOS 4 & 5 CURB DISPLACEMENT AND PAVEMENT CRACKS ON 33 rd STREET Southwest Construction Road is a two-lane undivided roadway in the north-south orientation. Southwest Construction Road is a four-lane undivided roadway at the south end where the alignment is in the west-east orientation. Southwest Construction Road narrows down to a two-lane divided roadway at the west end towards South Airfield Drive. There is a combination of concrete pavement sections and asphalt pavement sections along this alignment. This street also contains asphalt shoulders that are severely distressed in some areas. The main lanes were distressed with extensive longitudinal cracks, lateral cracks and potholes. Asphalt overlays were observed in several locations where severe distressed has occurred. There was one area where it was evident that consolidation of non-compact backfill around an existing utility line beneath the pavement was causing the pavement to settle. An asphalt overlay was placed to level the grades in this area. There is a stretch along this roadway where it abuts to an approximate 3(H):1(V) slope. This street was observed to be used by automobiles, by food catering trucks, construction vehicles and by employee buses. PHOTOS 6 & 7 PAVEMENT DISTRESS ON SOUTHWEST CONSTRUCTION ROAD ALLIANCE GEOTECHNICAL GROUP DE PAGE 3

8 1.2 PURPOSE AND SCOPE The purposes of this geotechnical investigation were to: 1) explore the subsurface conditions at the site, 2) provide boring logs that present subsurface conditions encountered including water level observations and laboratory test results, 3) provide comments on the presence and effect of expansive soils, non-compact trench backfill and tree root desiccation on the existing and proposed new roadways, 4) provide pavement subgrade preparation and concrete pavement section recommendations, 5) provide foundation recommendations for the light poles on 33 rd St and 6) provide comments on open cut construction for proposed utility repairs. This report was prepared in general accordance with AGG Proposal No. P E-R3 dated January 9, FIELD INVESTIGATION The field investigation consisted of drilling a total of fourteen (14) test borings along the pavement alignments to depths ranging from 15 to 25 feet. Borings B-1 thru B-8 were drilled on SW Construction Rd to depths of 15 feet below the existing grade with the exception of Boring B-3 and B-3A. Boring B-3 was originally located near a failed utility line that has caused the pavement to settle. Boring B-3 was advanced to a depth of 5 feet and was terminated above an existing utility line. This boring was offset to a new location and redrilled. The new boring location was labeled as Boring B-3A and was advanced to a depth of 10 feet below grade. Borings B-9 and B-10 were drilled on 31 st St to depths of 15 feet below the existing grade. Boring B-11 was drilled on 32 st St to a depth of 15 feet below the existing grade. Borings B-12 thru B-14 were drilled on 33 rd St to depths of 25 feet below the existing grade. A truck-mounted drilling rig was used to advance these borings and to obtain samples for laboratory evaluation. The borings were located at the approximate locations shown on the Plan of Borings (Figure 1). Undisturbed samples of the soils were obtained at intermittent intervals with standard, thinwalled, seamless tube samplers. The soil encountered in Borings B-12 thru B-14 was evaluated by the Texas Department of Transportation Penetrometer (TxDOT Cone) Test at 5-foot intervals. The TxDOT Cone is driven with the resulting penetration in inches recorded for 100 blows or with the number of blows recorded per 6 inch intervals for 12 inches, whichever comes first. The results of the TxDOT Cone test are recorded at the respective testing depths on Boring Logs of Boring B-12 thru B-14. ALLIANCE GEOTECHNICAL GROUP DE PAGE 4

9 These samples were extruded in the field, logged, sealed, and packaged to protect them from disturbance and maintain their in-situ moisture content during transportation to our laboratory. The results of the boring program are presented on the Logs of Borings (Figures 2 thru 16). A key to the descriptive terms and symbols used on the logs is presented on Figure LABORATORY TESTING Laboratory tests were performed on representative samples of the soil to aid in classification of the soil materials. These tests included Atterberg limits tests, moisture content tests and dry unit weight determinations. Hand penetrometer tests were performed on the soil samples to provide indications of the swell potential and the foundation bearing properties of the subsurface strata. The results of these tests are presented on the Logs of Borings (Figures 2 thru 16). To provide additional information about the swell characteristics of these soils (at their in-situ moisture conditions), absorption swell tests were performed on selected samples of the clay soils (see Figure 18). Soluble sulfate testing was performed to determine sulfate levels and the potential risks of lime-sulfate induced heave (see Figure 19). Lime series were also performed (see Figure 20). Miniature Harvard Compaction Tests were performed to assist in the evaluation of the relative density of the fill materials (see Figures 21 thru 25). 4.0 SITE AND SUBSURFACE CONDITIONS 4.1 GENERAL SITE CONDITIONS The four roadway alignments consist of asphalt pavement sections and concrete pavement sections. The grades beyond the roadway limits are relatively flat with the exception of a stretch on SW Construction Rd where the roadway abuts an approximate 3(H):1(V) slope. The existing pavement sections are in poor condition in many areas. The pavement is severely cracked in some locations and differential movements have occurred along the pavement alignments. Existing trees are present adjacent to the roadway in various areas with driplines extending over the roadway surface. Transverse and longitudinal pavement cracking has occurred in several areas. Cracking appears to be due to seasonal shrink/swell movements of the expansive soils below the roadway, due to ground shrinkage (settlement) ALLIANCE GEOTECHNICAL GROUP DE PAGE 5

10 caused by tree root desiccation and due to consolidation of non-compact fill that was placed above the existing utility lines 4.2 SUBSURFACE CONDITIONS Subsurface conditions encountered in the borings, including descriptions of the various strata and their depths and thickness, are presented on the Logs of Borings. Note that depth on all borings refers to the depth from the existing grade or ground surface present at the time of the investigation. Boundaries between the various soil types are approximate. 4.3 SITE GEOLOGY As shown on the Dallas sheet of the Geologic Atlas of Texas, the site is located in an area underlain by the Eagle Ford Shale. This formation typically consists of highly expansive clay and shaley clay strata underlain by unweathered shale. Soils derived from this formation are typically deep highly plastic clays exhibiting a high shrink/swell potential with variations in moisture content. These clay soils usually contain low resistivity levels and high sulfate levels that are corrosive to buried metals and concrete. 4.4 GROUNDWATER CONDITIONS The borings were advanced using continuous flight auger methods. Advancement of the borings using these methods allows observation of the initial zones of seepage. Groundwater was encountered within Borings B-12 thru B-14 during drilling at depths ranging from 13 to 16 feet at the time of this investigation. Shallower groundwater levels should be anticipated after periods of rain. It is not possible to accurately predict the magnitude of subsurface water fluctuations that might occur based upon short-term observations. The subsurface water conditions are subject to change with variations in climatic conditions and are functions of subsurface soil conditions, rainfall and water levels within nearby creeks, ponds, and adjacent drainage ditches. 5.0 ANALYSIS AND SUBGRADE RECOMMENDATIONS 5.1 SOIL MOVEMENTS The subsurface exploration revealed the presence of highly expansive clay soils. The existing clay soils have a moderate to high shrink/swell potential depending upon their ALLIANCE GEOTECHNICAL GROUP DE PAGE 6

11 existing soil moisture condition. Potential soil swell movement calculations were performed using swell test results, pocket penetrometer readings, and moisture content tests to estimate the swell potential of the soil. The potential soil swell movement values are based upon current soil moisture conditions and current grades at the test boring locations. Potential soil swell heave within a typical 10 foot deep active zone has been estimated to typically be in the range of 4 to 6 inches beneath the existing pavement (outside of the tree influenced areas). However within tree influenced areas, the potential soil swell heave has been estimated to exceed 8+ inches of active zone soil swell heave. Relatively large active zone differential movements in excess of 6 inches are likely between tree influenced areas and non tree areas if existing trees are removed during construction or if existing trees should die after the pavement is reconstructed. Additional differential pavement movements due to deep-seated soil swell are also possible between tree influenced areas and non tree areas (see below). See Section 6.7 regarding additional considerations related to trees that remain adjacent to the new roadway. NOTE 1: It should be noted that if the clay soils are allowed to significantly dry between the time the existing pavement is removed and the new pavement is placed, the potential vertical rise could significantly increase in all areas. In addition to swelling within a typical 10 foot deep active zone, the potential for additional deep-seated swell exists at this site. The assumed active zone swell values are upward soil movements that could occur due to typical seasonal moisture changes and soil swelling within the upper ten (10) feet as measured from finished grade. The deep-seated swell values are additional upward soil movements that could occur due to moisture changes and soil swelling below a typical ten (10) foot deep active-zone. Deep-seated swell could occur due to groundwater fluctuations or free water sources such as ponding water conditions, percolation of water in landscaped areas, leaking sprinkler lines and/or leaking utility lines that are not detected and repaired in an expedient manner. At this site, the deep-seated swell is estimated to be about 2 inches in non-tree influenced areas and about 4 inches of deep-seated soil swell in tree influenced areas. The risk of differential deep seated swell below pavements is generally not a high risk due to the low probability of deep water percolation below 10 foot depths but could occur if a free water source occurs over an extended period of time. Measures to minimize deep seated swell associated with free water sources are provided in the Appendix to this report. ALLIANCE GEOTECHNICAL GROUP DE PAGE 7

12 5.2 OPTIONAL SITE MODIFICATION TO REDUCE SOIL MOVEMENTS As mentioned above, large differential upward pavement movements are likely at this site due to soil swelling. NOTE 1: Differential movements could be particularly large in areas where trees are removed or where the pavement is widened and/or extended beyond the limits of the existing pavement due to moisture variations between existing paved and unpaved areas and between existing tree and non-tree areas as mentioned above. If large differential pavement movement is not acceptable, site preparation work will have to be performed in order to lower the potential differential movements to an acceptable level. This will be particularly important wherever existing trees will be removed, where pavement widening occurs or if construction occurs after a prolonged period of predominantly dry weather. If it is required that the differential PVR for the proposed new pavement be reduced, excavation and moisture conditioning of the in-situ clay soils will be required. AGG should be contacted for site preparation work recommendations in order to reduce the differential soil swell PVR to acceptable levels in areas where trees must be removed (regardless of the time of construction) and in widened areas (particularly if reconstruction is planned to begin after periods of dry weather). See Section 6.7 for potential settlements caused by existing trees that remain (or are planted) near the roadway. It is imperative that all cracks and joints in the pavement be sealed and maintained by routine sealing in order to minimize differential pavement deflections caused by soil swelling. It is also imperative that positive drainage be provided along the pavement edges to prevent ponding near the curb lines. 5.3 EXISTING FILL SOILS Existing fill soils were present across the subject alignments to depths ranging from 1.5 to 8 feet below the existing ground surface. See Table 1 below. The fill soils consist primarily of clay soils. ALLIANCE GEOTECHNICAL GROUP DE PAGE 8

13 TABLE 1 SUMMARY OF DEPTH OF FILL BORING ID DEPTH TO FILL B-1 8 B-2 4 B B-3A 2.5 B-4 2 B-5 6 B B B-8 7 B-9 4 B-10 5 B-11 3 B-12 4 B-13 7 B-14 8 Deep clay fill soils will consolidate/settle over time. The settlement is dependent on how the clay fill soils were placed and compacted and on the age of the fill material. If the existing fill soils were placed in an uncontrolled manner without engineering supervision and without proper moisture / compaction verification of each fill lift, excessive settlements / consolidation of the fill soils would occur. If the fill soils were placed in a controlled manner with proper moisture and compaction verification, the anticipated settlement is about 1 of the recompacted fill height. This can be verified if appropriate density reports are available from the time of the fill placement. Information regarding the age and manner in which these existing fill soils were placed was not available during this investigation. If verification density testing reports cannot be obtained for the existing fill, we recommend that the existing fill be tested for compaction. In order to provide adequate pavement support, we recommend that test pits and density testing be performed under the direction of an AGG geotechnical engineer to verify compaction to a minimum depth of 5 feet below final pavement subgrade. If compaction levels are less than 95 percent, excavation of the non-compact existing fill soils will need to be performed to a minimum depth of 5 feet below the bottom of pavement to provide the minimum pavement support required for design. ALLIANCE GEOTECHNICAL GROUP DE PAGE 9

14 Miniature Harvard Compaction Tests were performed on the fill materials to evaluate the relative density (See Tables 2 and 3). Soil settlement is dependent on load and time. Noncompact soils or soils with relative density less than 95 causes excessive settlement over time. Repetitive vehicle loading over non-compact fill soil will cause the soil to settle. Noncompact soils are susceptible for water retention within the voids and susceptible to water migration causing the respective soil to consolidate (settle) due to hydrocompaction and for the fill become very soft and compressible. This is evident at Borings B-9, B-11 and B-13. See Table 3. Future settlements will continue to occur within all non-compact fill, particularly within areas containing soft to very soft zones. TABLE 2 SOIL MATERIAL REFERENCE CURVE DATA Curve No Test Method Miniature Harvard Miniature Harvard Miniature Harvard Miniature Harvard Miniature Harvard Material Reference Curve Data Boring Tested Material Description ID Depth Dark gray and brown Clay with B feet tan and light gray Shaley Clay Optimum Moisture Max Dry Density (pcf) B feet Dark gray and brown Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Dark gray, tan and brown Clay Boring ID TABLE 3 APPROXIMATED PERCENT OF COMPACTION PER HARVARD MINIATURE TEST Depth Approximated Percent of Compaction Per Miniature Harvard Test Results Material Description Ref Curve Moisture Dry Density (pcf) Moisture Deviation Density B feet Dark gray and brown Clay B feet Tan and light gray Shaley Clay B feet Tan and light gray Shaley Clay B feet Tan and light gray Shaley Clay B feet Tan and light gray Shaley Clay to Dark gray and dark brown Clay B feet Dark gray to dark brown Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Dark gray and brown Clay B feet Dark gray and brown Clay ALLIANCE GEOTECHNICAL GROUP DE PAGE 10

15 Boring ID Approximated Percent of Compaction Per Miniature Harvard Test Results Dry Moisture Ref Depth Material Description Density Deviation Curve Moisture (pcf) Density B feet Dark gray and brown Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Tan Clay B feet Tan Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Brown Clay B feet Dark gray and tan Clay B feet Dark gray and tan Clay B feet Tan, brown and dark gray Clay B feet Tan, brown and dark gray Clay B feet Dark gray, brown and tan Clay B feet Dark gray, brown and tan Clay B feet Dark gray, brown and tan Clay Pavement settlements could still continue to occur where deeper non-compact fill is present (depending on the age of the fill). If it is desired to minimize settlements in sensitive pavement areas, consideration could be given to removing and recompacting, in thin compacted lifts, all non-compact fill if the existing fill is less than 20 years old. However, if the fill was placed over 20 years ago, the majority of the consolidation may have already occurred and future settlements should likely be on the order of 1 of the fill height. These settlement estimates assume that no deleterious materials are present within the fill materials, that the existing grades are not being raised by more than 2 feet, and that continued consolidation due to hydrocompaction does not occur. If the grades are raised by more than 2 feet, then additional settlement should be anticipated. ALLIANCE GEOTECHNICAL GROUP DE PAGE 11

16 5.4 PROOFROLLING AND FILL PLACEMENT Prior to placing fill, the exposed subgrade in areas to receive fill should be stripped and proofrolled. Proofrolling should also be performed in cut areas after cutting to final grades. Proofrolling can generally be accomplished using a heavy (25 ton or greater total weight) pneumatic tired roller making several passes over the areas. The proofrolling operations should be performed under the direction of an AGG geotechnical engineer. Where soft or compressible zones are encountered, these areas should be removed to a firm subgrade as determined by AGG. Any resulting void areas should be backfilled to finished subgrade in 8 inch compacted lifts as specified below. After completion of proofrolling, the ground surface should then be scarified to a depth of 8 inches and recompacted to levels specified below prior to placement of additional fill. We recommend that fill be placed in 8 inch horizontal benched lifts. Clay fill materials should be placed in 8 inch loose lifts and compacted to a minimum of 98 percent of the maximum density as determined by ASTM D 698 between -1 and +2 of its optimum moisture content. 5.5 SITE GRADING AND DRAINAGE All grading should provide positive drainage away from the proposed roadway and should prevent water from collecting or discharging near the pavements. Water must not be permitted to pond adjacent to or near the pavements during or after construction. Otherwise, differential upward soil swell movements will be exacerbated. The pavements will be subject to large post construction movement (see Section 5.1 of this report). Joints in the concrete pavements should be sealed to prevent the infiltration of water. Since post construction movement of pavement will occur, joints should be periodically inspected and resealed along with pavement cracks that will occur. 6.0 PAVEMENT RECOMMENDATIONS It is understood that the traffic lanes of 31 st St, 32 nd St and 33 rd St will be replaced with new concrete pavements and that the traffic lanes of SW Construction Road will be replaced with full-depth asphalt pavement. These subject alignments are anticipated to be utilized by automobiles, food catering trucks, commercial delivery trucks, DFW Airport Employee Buses and construction vehicles. ALLIANCE GEOTECHNICAL GROUP DE PAGE 12

17 6.1 PAVEMENT SECTIONS FOR 31 ST, 32 ND & 33 RD STREET It is understood that the subject alignments along 31 st, 32 nd and 33 rd St will be replaced with pavement sections provided in DFW Design Criteria Manual 2015 Division 34, These provided pavement sections were evaluated to determine the estimated Equivalent Single Axle Load (ESAL) that the pavement sections can handle. The pavement sections were as follow: DFW Roadway Structural Pavement Section Option A (4400 psi) 10-inch thick CRCP 3-inch hot mix asphalt concrete (HMAC) 9-inch Lime Stabilized Subgrade at 8 percent lime by weight DFW Roadway Structural Pavement Section Option B (4400 psi) 9-inch thick CRCP 2-inch HMAC 6-inch Cement Treated Base 9-inch Lime Stabilized Subgrade at 8 percent lime by weight NOTE 1: If lime-stabilization is performed, we recommend that additional soluble sulfate testing be performed on the pavement subgrade once final grading of the pavement has been achieved to verify that that sulfate levels are below 3,000 ppm. Otherwise, crushed stone flex base can be utilized in lieu of lime stabilization. The pavement evaluation of these two sections projected Option A to be able to handle approximately 6.5 million ESALs and projected Option B to be able to handle approximately 3.4 million ESALs. The design life for these pavement sections can be evaluated if traffic data is provided. The concrete should have a minimum 28 day compressive strength of 4,400 psi and a minimum 28 day flexural strength of 617 psi. Concrete quality will be important in order to produce the desired flexural strength and long term durability. Proper joint placement and design is critical to pavement performance. Load transfer at all joints and maintenance of watertight joints should be provided. Control joints should be sawed as soon as possible after placing concrete and before shrinkage cracks occur. All joints including sawed joints should be properly cleaned and sealed as soon as possible to avoid infiltration of water. ALLIANCE GEOTECHNICAL GROUP DE PAGE 13

18 It is understood that the alignments along 31 st St, 32 nd St and 33 rd St will be designed as continuously reinforced concrete pavements. Per TxDOT s Pavement Design Manual dated July 9 th, 2018; contraction joints should be implemented in rigid pavement design to relieve tensile stresses related to the variation in temperature and moisture within the concrete. A longitudinal contraction joint is required for concrete placement width that is greater than 15 feet. The depth of the longitudinal contraction joint should be saw-cut to 1/3 of the slab thickness. For Continuously Reinforced Concrete Pavement (CRCP), single tie bars are spaced at 48 inches in addition to the transverse steel bars along the longitudinal contraction joints. CRCP pavement design does not require transverse contraction joints. Refer to Chapter 9 Section 7 of TxDOT s Pavement Design Manual dated July 9 th, 2018 for additional information regarding pavement joints. NOTE 2: We recommend that the perimeter of the pavements have a stiffening curb and gutter (or turned down beam where asphalt shoulders are used) to improve performance and reduce cracking due to heavy wheel loads near the edge of the pavements. 6.2 PAVEMENT ANALYSES FOR SOUTHWEST CONSTRUCTION ROAD It is understood that full-depth asphalt pavement section is preferred for the reconstruction of Southwest Construction Road. Various types of vehicles travel along Southwest Construction Road such as automobiles, DFW employee busses, construction equipment, etc. However, actual traffic data along Southwest Construction Road was not available at the time of the analyses. Sky Chef and Gate Gourmet s anticipated catering schedule and assumptions for DFW employee bus schedule provided and/or approved by DFW Airport was utilized to develop the proposed pavement section for Southwest Construction Road. DFW Airport provided the approximated daily average catering schedule for Sky Chef and Gate Gourmet. Sky Chef performs about 300 daily deliveries and Gate Gourmet performs about 350 daily deliveries to the aircrafts. Based on the conversation with the personnel at the two catering companies, Sky Chef has large and small catering trucks whereas Gate Gourmet has one size catering trucks. NOTE: The catering trucks are single-unit trucks with various axle load configuration. See Appendix D for the respective axle loads. The axle loads of the catering trucks were retrieved from the specification stickers placed inside the catering trucks at DFW Airport. See the Appendix C for the respective specification stickers. It is understood that DFW employee busses also use this subject alignment to access the parking yard behind the US Post Office on 32 nd St. The entrance into this parking yard is ALLIANCE GEOTECHNICAL GROUP DE PAGE 14

19 directly across from AOA Gate Access #327. However, a bus traffic schedule was not provided along this alignment into this yard. The daily average assumption (approved by DFW Airport) of 50 busses travel along this alignment to this parking yard. See Appendix C for the axle loads of the DFW employee bus. In addition, larger catering trucks serving Aircraft A380 and commercial delivery trucks are also anticipated to travel along this alignment. The gross vehicle weight rating of 50,700 lb for the larger catering truck was retrieved from a published article. See Appendix C to reference the article. It was assumed that a daily average total of 20 of the larger catering trucks (approved by DFW Airport) travel along the subject alignment from both Sky Chef and Gate Gourmet. The commercial delivery trucks were assumed to be WB-50 trucks with gross vehicle weight rating of 80,000 lb. It was noted by DFW Airport that an average total of 20 commercial delivery trucks delivers at both Sky Chef & Gate Gourmet. See Appendix D for the assumed respective axle loads of each respective trucks. The pavement section recommendations for Southwest Construction Road provided below were designed based upon AASHTO Guide for Design of Pavement Structures using WinPAS 12 computer program. A summary of the inputs are provided below for the HMAC pavement: Initial Serviceability: 4.2 Terminal Serviceability: 2.25 Reliability Level: 90 Overall Standard Deviation: 0.45 Subgrade Resilient Modulus 4,118 psi (CBR of 3) TABLE 4. RECOMMENDED MAIN LANE PAVEMENT SECTIONS PROPOSED PAVEMENT SECTIONS FOR SW CONSTRUCTION ROAD HMAC SECTION FOR 10 YEAR DESIGN LIFE 3.5 inches Type C Surface Course 4 inches Type B Binder Course 12 inches Flex Base (2 6 inch lifts) (See Section 6.4) 8 inches Lime Stabilized Subgrade (See Section 6.3) HMAC SECTION FOR 20 YEAR DESIGN LIFE 4 inches Type C Surface Course 5 inches Type B Binder Course 12 inches Flex Base (2 6 inch lifts) (See Section 6.4) 8 inches Lime Stabilized Subgrade (See Section 6.3) ALLIANCE GEOTECHNICAL GROUP DE PAGE 15

20 It is also understood that the existing asphalt shoulders at the north end of Southwest Construction Road will be reconstructed. The existing shoulder is experiencing severe distress. The distress varies from alligator cracks to displacement to separation from the main lanes. Shoulders are constructed to protect the moisture beneath the abutted main lane, to provide edge support, minimize seepage further away from the traffic lane and to provide for emergency pull off. Generally, deterioration of the shoulder pavements can be attributed to a number of factors such as daily traffic usage, creep from abutted slopes, moisture loss along the edge causing edge drop off/settlement, moisture absorption from nearby trees, poor maintenance, etc. Shoulders are not designed and are not intended for daily traffic. However, it is understood that Southwest Construction Road is an undivided two-lane roadway that is utilized by large vehicles, such as DFW employee busses and construction equipment, which causes opposite vehicular traffic to occasionally divert into the shoulders. As stated, shoulders are not designed for traffic, but for the purpose of designing the shoulder section provided in Table 5, the following traffic assumptions were made: 10 daily automobiles, 3 daily large catering trucks, 3 daily small catering trucks, 3 daily catering trucks serving Aircraft A380, 3 daily DFW employee busses, and 3 daily WB-50 trucks for a design life of 20 years. See Appendix D for the analyses summary. TABLE 5. RECOMMENDED SHOULDER PAVEMENT SECTION PROPOSED PAVEMENT SECTION FOR SW CONSTRUCTION ROAD SHOULDERS SHOULDER SECTION 4 inches Type C Surface Course 14 inches of Flex Base (See Section 6.4) 8 inches Compacted Subgrade* (See Section 6.5) *Although not required by design, placement of lime-stabilized soils beneath the flex base layer could be used to improve performance and reduce maintenance. The asphaltic concrete pavement (ACP) construction should comply with requirements of TxDOT, Item SS The asphaltic concrete should be placed and compacted in accordance with either TxDOT Item 334 or Item 341 (2014 TxDOT Specifications). ALLIANCE GEOTECHNICAL GROUP DE PAGE 16

21 6.3 STABILIZATION WITH HYDRATED LIME The subsurface exploration revealed surficial materials present beneath the pavement and base consisting of highly plastic clay soils having a high shrink/swell potential. These clay soils react with hydrated lime, which serves to improve their support value and provide a firm, uniform subgrade beneath the paving. NOTE 1: NOTE 2: The subject alignments are located within the Eagle Ford Formation which is known to have very high soluble sulfate levels within seams and pockets within the shaley clay soils. If liming is to be considered, it is recommended that the subgrade be inspected by an AGG engineer or geologist after grading to the final subgrade elevation. Soil samples should be obtained during the subgrade inspection and tested to verify the sulfate content does not exceed 3,000 ppm. The majority of the test results had soluble sulfate levels below 3,000 ppm with the exception of samples at Borings B-8 and B- 12 which had sulfate levels as high as 25,400 and 5,587, respectively. However, high levels of sulfates can be present in seams and pockets in areas along the pavement alignment. If soluble sulfate levels exceed 3,000 ppm, lime-stabilization should not be performed due to the risk of sulfate induced heave. In lieu of lime stabilization, crushed stone flex base can be used. See Section 6.4 for crushed stone flex base recommendations. As an alternative to crushed stone flex base, a thickened pavement section over a compacted subgrade without lime treatment may be used. After final grading (prior to liming), it should be verified that at least 50 of the soils to be lime-treated consist of raw untreated clay. If the thickness of lime treated soils exposed along the subgrade after excavation is over 4 inches, a minimum of four (4) inches of the lime treated soils should be removed and replaced with on-site clay for effective stabilization. Based on the anticipated soil materials to be exposed at pavement subgrade, eight (8) percent hydrated lime by dry weight (54 pounds per square yard per 9-inch depth) is anticipated for stabilization of the existing clay subgrade. The actual lime requirement will depend upon the actual subgrade soils exposed at final grade and should be determined at the time of construction along with sulfate content determinations to verify sulfate levels are less than 3,000 ppm. Soluble sulfate testing (see Figure 19) resulted in sulfate levels ranging from less than 100 to 25,400 ppm. The results of 25,400 ppm was tested at depth 3-4 feet in Boring B-8. The subgrade at the boring locations (at depths of 0 to 3 feet) has sulfate content ranging from less than 100 to 3,567 ppm. A risk of lime / sulfate heave occurs when sulfate levels are in excess of 3,000 ppm. If lime-stabilization is performed, we recommend that additional ALLIANCE GEOTECHNICAL GROUP DE PAGE 17

22 soluble sulfate testing be performed on the pavement subgrade once final grading of the pavement has been achieved to verify that that sulfate levels are below 3,000 ppm. NOTE 3: If the risk of lime/sulfate induced heave is to be avoided, crushed stone flex base as an alternative subgrade modification in lieu of lime stabilization. See Section 6.4. The lime should be thoroughly mixed and blended with the active subgrade soil (TxDOT Item 260) and the mixture compacted to a minimum of 98 percent of maximum dry density as determined in accordance with ASTM D698, within -2 to +2 of the soil's optimum moisture content. We recommend that this lime stabilization extend 1 to 2 feet beyond exposed pavement edges, if possible, in order to reduce the effects of shrinkage during extended dry periods. After final grading has been achieved, depth checks and PI verification checks should be performed to verify that the specified depth of stabilization is present. Sand should be specifically prohibited beneath pavement areas during final grading (after stabilization), since these more porous soils can allow water inflow, resulting in heave and strength loss of subgrade soils. It should be specified that only lime-stabilized soil will be allowed for fine grading. After fine grading each area in preparation for paving, the subgrade surface should be lightly moistened, as needed, and recompacted to obtain a tight nonyielding subgrade. Project specifications should allow a curing period between initial and final mixing of the lime/soil mixture. After initial mixing, the lime treated subgrade should be lightly rolled and maintained at or within 5 percentage points above the soil's optimum moisture content until final mixing and compaction. We recommend a 3-day curing period for these soils. The following gradation requirements are recommended for the stabilized materials prior to final compaction: Percent Minimum Passing 1 3/4" Sieve 100 Minimum Passing 3/4" Sieve 85 Minimum Passing No. 4 Sieve 60 All non-slaking aggregates retained on the No. 4 sieve should be removed prior to testing. The prepared subgrade should be protected and moist cured or sealed with a bituminous material for a minimum of 7 days or until the pavement materials are placed. Pavement ALLIANCE GEOTECHNICAL GROUP DE PAGE 18

23 areas should be graded at all times to prevent ponding and infiltration of excessive moisture on or adjacent to the pavement areas. Due to the presence of expansive clay soils, pavement movements should be anticipated. Inspection during construction is particularly important to insure proper construction procedures are followed. 6.4 CRUSHED STONE BASE In lieu of lime stabilization, eight (8) inches of crushed Chico stone flex base should be used. The flex base should be compacted at optimum to +2 above optimum to a minimum of 95 Modified Proctor density (ASTM D1557). The base materials should comply with TxDOT Item 247, Type A, Grade 1. We recommend that the base materials extend at least two feet beyond the pavement edges. Crushed stone base is recommended due to its resistance to sulfate attack. Prior to placing the flex base, the subgrade should be proofrolled prior to subgrade compaction. Proofrolling should be performed in accordance with Section 5.4 of this report. Prior to placing flex base, the upper eight (8) inches of the subgrade soils should be scarified and compacted at -1 to +2 percentage points of optimum moisture to a minimum of 98 Standard Proctor density (ASTM D 698). If a rain event occurs prior to placement and compaction of the flex base, the subgrade should be aerated and re-tested prior to paving. 6.5 RECOMPACTED SUBGRADE The upper eight-(8) inches of subgrade soil should be compacted at -1 to +2 percentage points of optimum moisture to a minimum of 98 Standard Proctor density (ASTM D 698) prior to placement of any new fill. The subgrade should be proof-rolled prior to subgrade compaction. Only on-site soil should be used for fine grading the pavement areas. After fine grading, the subgrade should again be watered if needed and re-compacted in order to reachieve the moisture and density levels discussed above and provide a tight non-yielding subgrade. Sand should not be allowed for use in fine grading the pavement areas. The subgrade moisture content and density must be maintained until the pavement construction is completed. If a rain event occurs prior to placement of the concrete, the subgrade should be allowed to dry adequately then re-tested prior to paving. ALLIANCE GEOTECHNICAL GROUP DE PAGE 19

24 6.6 PAVEMENT CONSIDERATIONS All joints and pavements should be inspected at regular intervals to ensure proper performance and to prevent crack propagation. The soils at the site are active and differential heave within the paving areas will occur. See Section 5.1 of this report. The service life of paving may be reduced due to water infiltration into subgrade soils through heave induced cracks in the paving section. This will result in softening and loss of strength of the subgrade soils. A regular maintenance program to seal paving cracks will help prolong the service life of the paving. The life of the pavement can be increased with proper drainage. Areas should be graded to prevent ponding adjacent to curbs or pavement edges. Backfill materials, which could hold water behind the curb, should not be permitted. Flat pavement grades should be avoided. 6.7 TREE EFFECTS Large mature trees are present in some areas with drip lines that extend near or over the proposed new pavement. The roots of mature trees absorb large amounts of moisture from the supporting soils to depths of over 15 feet. The lateral limits of tree root influence extend at least 5 feet beyond the unpruned drip line (and to much greater distances when the ground beneath the drip lines is paved and/or if multiple trees are present in the area). The tree root moisture absorption from supporting soil will cause the soil to settle. To reduce future settlement after reconstruction, root barriers and/or irrigated tree wells could be considered. An arborist or landscape architect should be contacted regarding the required depth of the root barrier and whether or not this is a viable solution. Root barriers along both curb lines would require large roots to be severed. This might kill the trees. If this occurred, large pavement heave would then occur as described above (same as removing trees). If the barriers are effective in reducing soil suction from the root systems, large differential heave would still occur as the soils regain lost moisture causing differential heave due to soil swelling. Due to these concerns, root barriers are probably not a viable solution at this time for existing trees. Root barriers and/or irrigated tree wells should be considered for new trees to be planted along the roadway. In our opinion, the most practical solution is to thicken the pavement near the tree covered areas. An additional 1 to 2 inches of concrete (over the required design thickness) could be used near the tree areas to provide additional rigidity to reduce differential deflections caused by post construction shrink/swell movements. Additional steel reinforcement could be used to further stiffen the pavement. Larger bars on a closer spacing and two mats of ALLIANCE GEOTECHNICAL GROUP DE PAGE 20

25 steel should be considered. A structural engineer should be consulted regarding the most cost effective reinforcement design for the thickened sections. If the pavement is thickened and stiffened as described above, differential deflections should be reduced. If differential settlements due to shrinkage caused by tree roots become objectionable, these areas could be mudjacked in the future as needed to level the pavement. 7.0 LIGHT POLE FOUNDATION RECOMMENDATIONS It is understood that new light poles will be constructed along 33 rd St (Borings B-12 thru B- 14). The light poles can supported by straight shaft piers. 7.1 PIER RECOMMENDATIONS If some foundation movement is acceptable, consideration can be given to supporting the proposed light poles on straight shaft pier foundations founded in the shaley clay and weathered shale. The piers should be founded at minimum depths of 15 feet below the existing ground surface in very stiff to hard clay and shaley clay soils or shale. The recommended allowable bearing capacity for the piers founded in very stiff to hard clay soils is 5,000 psf. This value contains a factor-of safety of at least 3.0 based on the results of geotechnical borings. NOTE: Sulfate resistant concrete should be used for all piers and pier caps. See Section 8.3 of this report. 7.2 RESISTANCE OF LATERAL WINDS LOADS For evaluating shaft deflections, L-Pile parameters for the clay soil are provided below for individual laterally loaded drilled shafts. The parameters indicated below do not include reductions related to group effects (see Note 1 below). ALLIANCE GEOTECHNICAL GROUP DE PAGE 21

26 Neglect passive resistance within upper 5 feet below finish grade or 4 feet below top of pier, whichever is deeper. Water Level Condition Above Water (5 to 10 feet) FOR OVERBURDEN SOILS (for depths greater than 5 feet) Material Type for LPile Stiff Clay without Free Water Undrained Cohesion (psf) Total Soil Unit Weight (pcf) Strain Factor E50 Static Horizontal Modulus of Subgrade Reaction, k (pci) 1, Above Water (Below 10 feet) Stiff Clay without Free Water 1, Below Water (Below 10 feet) Stiff Clay with Water 1, NOTE 1: Reduction factors must be applied to account for group effects for laterally loaded piers. If the center to center spacing is less than 7D for laterally loaded piers, then an L-Pile group study using the Ensoft Group Pile Program would be required to determine the appropriate reduction factors that must be applied for laterally loaded piers. Alliance Geotechnical Group should be retained to work with the Structural Engineer in performing the Group Pile Analyses, if required. This includes group effects in the direction of loading, side by side effects, and effects in skewed directions. Otherwise, the Structural Engineer could use the information in the below paragraphs to conservatively approximate reductions for group effects. In order to determine the appropriate reduction for group effects of a pier in a group, the reduction for side by side effects (R SS), the reduction for in-line loading effects (R IL), and the reduction for skewed effects (R SK) will need to be determined for each adjacent pier and multiplied together to determine the reduction factor for the subject pier in the group. The reduction for in-line loading effects (R IL) will consist of either leading pier (R LP) or trailing pier (R TP). Each of these reductions should be determined as recommended below. Reduction due to Side by Side effects(r SS) For 1D center to center spacing (piers touching), 64 of the lateral resistance should be used. Where the center to center spacing is 4D, no reduction is necessary. For a spacing between 1D and 4D, a straight line interpolation should be used. ALLIANCE GEOTECHNICAL GROUP DE PAGE 22

27 Reduction due to Leading Pier (R LP) For 1D center to center spacing (piers touching), 70 of the lateral resistance should be used. Where the center to center spacing is 4D, no reduction is necessary. For a spacing between 1D and 4D, a straight line interpolation should be used. Reduction due to Trailing Pier (R TP) For 1D center to center spacing (piers touching), 47 of the lateral resistance should be used. Where the center to center spacing is 4D, 80 of the lateral resistance should be used. For a spacing between 1D and 4D, a straight line interpolation should be used between the 47 to 80 of lateral resistance. Where the center to center spacing is 7D, no reduction is necessary. For a spacing between 4D and 7D, a straight line interpolation should be used between the 80 and 100 of lateral resistance. Reduction due to Skewed Pier (R SK) The reduction factor for skewed piers (piers neither side-by-side or in line with the direction of loading) should be determined by the below formula. R SK = (R IL2 cos 2 Ø + R SS2 sin 2 Ø) 1/2 The reduction for in-line loading effects (R IL) will consist of either leading pier (R LP) or trailing pier (R TP) whichever one is applicable to the loading direction. The center to center spacing is based upon r/d and Ø (where Ø is the angle between the direction of loading and the line between the piers as shown in the detail below). NOTE 2: For all of the above reduction factors, if different size piers are used in a group, D used in the above formulas should be the largest pier diameter in the group. ALLIANCE GEOTECHNICAL GROUP DE PAGE 23

28 7.3 DRILLED SHAFT SOIL INDUCED UPLIFT LOADS All piers will be subject to uplift forces as a result of swelling within the overlying clays. The piers should have sufficient continuous vertical reinforcing steel extending to the bottom of the piers to resist the computed net uplift loads (uplift less dead load). The magnitude of the uplift loads varies with the shaft diameter, soil parameters, free water sources, and the depth of the active clays acting on the shaft. The uplift pressures can be approximated at this site by assuming a uniform uplift pressure of 2,500 pounds per square foot acting on the shaft perimeter for a depth of 15 feet. 7.4 DRILLED SHAFT CONSTRUCTION CONSIDERATIONS Groundwater was encountered within Borings B-12 thru B-14 during drilling at depths ranging from 13 to 16 feet at the time of this investigation. Shallower groundwater could be encountered after wet weather periods. If minor water seepage is occurring, the pier steel and concrete should be placed immediately after drilling. If excessive groundwater infiltration or caving soil is encountered, temporary casing seated below the seepage caving zone should be used under the direction of AGG. Concrete used for the shafts should have a slump of 6 inches plus or minus 1 inch and placed in a manner to avoid striking the reinforcing steel and walls of the shaft during placement. Complete installation of individual piers should be accomplished within a 4-hour period in order to help minimize deterioration of bearing surfaces and to minimize caving and groundwater infiltration. The drilling of individual shafts should be excavated in a continuous operation and concrete placed as soon as practical. No shaft should be left open for more than 4 hours. We recommend that Alliance Geotechnical Group be retained to observe and document the drilled pier construction. The engineer, or his representative, should document the shaft diameter, depth, cleanliness, plumbness of the shaft, and the type of bearing material. Significant deviations from the specified or anticipated conditions should be reported to the owner's representative and to the Structural Engineer. The drilled pier excavation should be observed to verify the bottom of the pier hole is dry and thoroughly cleaned of cuttings after completion and prior to concrete placement. NOTE 1: Mushrooming should not be allowed around piers, pier caps or grade beams. ALLIANCE GEOTECHNICAL GROUP DE PAGE 24

29 8.0 UTILITY REPAIR CONSIDERATIONS It is understood that utility repairs will be performed at various locations for existing utility lines beneath the subject pavement prior to placing new pavement sections. It is understood that open cut construction method will be utilized to expose the utility lines for repair. 8.1 OPEN CUT EXCAVATIONS It is understood that open cut trench excavations will be performed to expose the existing utility lines for repairs. The depth of the trench excavation is currently unknown. Subsurface conditions encountered along the alignments will vary from existing fill, clay, shaley clay and shale. Based upon the results of the test borings, groundwater should be anticipated at approximate depths ranging from 13 to 16 feet below the existing grade. Shallow groundwater should be anticipated in all areas if construction is performed during wet weather periods. The clay soils are jointed. The shaley clay soils are fissured, jointed, and blocky with slickensided fractures. Sloughing of the fill soils and highly jointed, very blocky, slickensided shaley clay should be anticipated. Sloughing should be anticipated during the excavation and installation operations. For all excavations at this site, it will be necessary to employ either sloped excavations or temporary bracing in accordance with OSHA regulations. General guidelines for design are discussed in the following sections. See Section 8.3 regarding Construction Considerations. Recommended slope ratios for the respective soil conditions are presented graphically on Figure 26. Trench excavations encountering submerged soils from which water is seeping should be cut back along flatter slopes as indicated on Figure 26. Trench excavations at this site should be cut back in accordance with OSHA regulations. It should be recognized that free standing slopes will be less stable when influenced by groundwater or saturated by rain. The clay soils and shaley clay soils are fissured, jointed, blocky, and slickensided. As a result, the soils that will be exposed within the trench excavations will potentially be unstable even for cuts which remain open for short durations. Surcharge loads, such as those resulting from excavation spoil, or equipment, should be placed no closer than five (5) feet from the crest of the slope and in accordance with OSHA regulations. Vehicle traffic should be maintained at least five feet from the edge of the crest. ALLIANCE GEOTECHNICAL GROUP DE PAGE 25

30 Excavation may encounter non-compact fill soils placed during previous construction of underground utilities. If encountered, these fill soils should be sheeted, shored, and braced, or laid back on slopes no steeper than 1.5 (H): 1(V) short term (less than 8 hours) and no steeper than 2 (H): 1(V) long term (over 8 hours). The contractor will need to take measures to avoid undermining and damaging the existing underground utilities. 8.2 BRACING/SHORING Where site limitations require excavations to have vertical side walls, an internal bracing system will be necessary. Bracing may consist of timber or steel shoring or manufactured steel trench braces. The lateral pressure distribution to be used in the design of excavation bracing may be determined as presented on Figure 27. It should be recognized that pressures are not included from hydrostatic pressures, surcharge loads, or traffic live loads at excavation side walls, dynamic loads, and vibration, which if present, must be included in bracing design. The excavation support system should be designed by a shoring specialist. 8.3 CONSTRUCTION CONSIDERATIONS It should be anticipated that groundwater will be encountered at all areas after periods of heavy rain. A system of ditches, sumps, deep wells and/or dual staged well points, and pumping will be required to provide groundwater control. The design of the actual dewatering system required is the contractor s responsibility. This includes the control of tailwater flow through previous backfilled sections and/or existing adjacent utility trenches. Prior to excavation, the alignment should be dewatered whereby the groundwater level is lowered to an elevation of at least 5 feet below the deepest required excavation. Confirmation of adequate dewatering along the alignment should be verified prior to beginning excavation. NOTE 1: NOTE 2: NOTE 3: The groundwater level should be evaluated along the alignment prior to making any excavations. This will allow the contractor to take appropriate measures prior to beginning work in each area. Excessive caving and bottom heave (invert blowout) and/or softening of the foundation subgrade is likely in areas where proper dewatering is not performed prior to making trench excavations. If this occurs, AGG should be contacted immediately. The soils at this site are very corrosive to buried metals and concrete. Adequate corrosion protection measures should be used to protect all buried metals. Sulfate resistant concrete mix designs utilizing fly ash are recommended for all below grade concrete. The sulfate resistant mix design should include the type and amount of cement and the type and amount of fly ash proposed. Since Type V cement is not locally available, we recommend ALLIANCE GEOTECHNICAL GROUP DE PAGE 26

31 that a fly ash/cement mix design utilizing Type II cement and 25 Type F fly ash with a low C3A concentration and a maximum water/cement ratio of 0.45 (or an approved equal) be used for concrete in contact with these site soils due to its resistance to sulfate attack. We recommend that additional ACI requirements for Class 3 exposure (sulfates that exceed 20,000 ppm) be considered for implementation at this site. We recommend that these ACI guidelines be considered during design. The following guidelines are presented to aid in the development of the excavation plans: Surface areas behind the crest of the excavations should be graded so that surface water does not pond within 15 feet of the crest, nor drain into the excavation. Heavy material stockpiles should not be placed near the crest of slopes per OSHA requirements. Similarly, heavy construction equipment should not pass over or be parked within 5 feet of the crest. The crest of slopes should be continually monitored for evidence of movement or potential problems. Freestanding slopes will become less stable when influenced by groundwater or saturation by rain. Identify other sources that might affect trench stability. Identify underground utilities prior to the start of excavation. Inspect trench excavations prior to the start of each work shift by qualified personnel. Continuously monitor trench excavations by qualified personnel during construction. Immediately inspect trench excavations following a rain event or other water intrusion by qualified personnel. Inspect trench excavations by qualified personnel when changing soil conditions are encountered or after any occurrence that could have affected trench stability. Test and monitor for atmospheric hazards (i.e. low oxygen levels, hazardous fumes, toxic gases) within trench excavations. 8.4 TRENCH BACKFILL The excavated soils can be used for trench backfill. Use of rock fragments greater than six (6) inches in any dimension should be prohibited since attaining uniform moisture and density without voids would be difficult. The backfill should be placed in thin compacted lifts as specified below. The fill materials should be free of surficial vegetation or debris. The on-site clay and shaley clay soils should be placed in 8 inch horizontal loose lifts and compacted to at least 95 ASTM D698 at optimum to +4 above optimum moisture. For fill depths below 12 feet or where it is desired to reduce post-construction settlements, the ALLIANCE GEOTECHNICAL GROUP DE PAGE 27

32 compaction level should be increased to a minimum of 98 ASTM D698, at -1 to +2 of optimum moisture. Anticipated settlements should be on the order of 1 of the total fill height. 9.0 FIELD SUPERVISION AND CONSTRUCTION TESTING Field density and moisture content determinations should be made on each lift of fill with a minimum of 1 test per lift per 100 linear feet for the roadway and a minimum of 1 test per lift per 150 linear feet for trench backfill. Supervision by the field technician and the project engineer is required. Some adjustments in the test frequencies may be required based upon the general fill types and soil conditions at the time of fill placement. Many problems can be avoided or solved in the field if proper inspection and testing services are provided. It is recommended that site preparation, concrete placement, and fill compaction be monitored by a qualified engineering technician. Density tests should be performed to verify compaction and moisture content of any earthwork. Inspection should be performed prior to and during concrete placement operations LIMITATIONS The professional services, which have been performed, the findings obtained, and the recommendations prepared were accomplished in accordance with currently accepted geotechnical engineering principles and practices. The possibility always exists that the subsurface conditions at the site may vary somewhat from those encountered in the test borings. The number and spacing of test borings were chosen in such a manner as to decrease the possibility of undiscovered abnormalities, while considering the nature of loading, size, and cost of the project. If there are any unusual conditions differing significantly from those described herein, Alliance Geotechnical Group should be notified to review the effects on the performance of the recommended foundation system. The recommendations given in this report were prepared exclusively for the use of client and their client and consultants. The information supplied herein is applicable only for the design of the previously described development to be constructed at locations indicated at this site and should not be used for any other structures, locations, or for any other purpose. We will retain the samples acquired for this project for a period of 30 days subsequent to the submittal date printed on the report. After this period, the samples will be discarded unless otherwise notified by the owner in writing. ALLIANCE GEOTECHNICAL GROUP DE PAGE 28

33 FIGURES ALLIANCE GEOTECHNICAL GROUP DE18-047

34 Project No: DE PLAN OF BORINGS SW CONSTRUCTION RD, 31ST ST, 32ND ST, 33RD ST REHABILITATION DFW AIRPORT, TEXAS Figure No: 1

35 LOG OF BORING B-1 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/24/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain " CONCRETE Lime-Treated CLAY (FILL) Dark gray and brown CLAY (FILL) Tan and light gray shaley CLAY (FILL) Dark gray to dark brown CLAY w/ calcareous nodules (FILL) Dark brown CLAY, jointed, w/ calcareous nodules Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:2

36 LOG OF BORING B-2 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/24/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain " CONCRETE Lime-Treated CLAY (FILL) Dark gray and tan CLAY w/ calcareous nodules (FILL) Dark gray and dark brown CLAY, jointed, w/ calcareous nodules Brown CLAY, jointed, w/ calcareous nodules Tan CLAY, jointed, w/ calcareous nodules Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:3

37 LOG OF BORING B-3 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/24/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain 0 8" CONCRETE Lime-Treated CLAY (FILL) Dark gray and brown CLAY (FILL) Boring terminated at 5' due to utility concerns Notes: Alliance Geotechnical Group, Inc. FIGURE:4

38 LOG OF BORING B-3A Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/27/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain " CONCRETE Lime-Treated CLAY (FILL) Dark brown CLAY, jointed, w/ calcareous nodules Dark brown to brown CLAY, jointed, w/ calcareous nodules Tan CLAY, jointed, w/ calcareous nodules Tan and light gray shaley CLAY, jointed, w/ calcareous deposits and Bentonite seams Boring terminated at 10' Notes: Alliance Geotechnical Group, Inc. FIGURE:5

39 LOG OF BORING B-4 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/24/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain 0 8" ASPHALT Lime-Treated CLAY (FILL) Gray and brown CLAY, jointed, w/ calcareous nodules Brown to tan CLAY, jointed, w/ calcareous nodules Tan CLAY, jointed, w/ calcareous deposits and iron stains Tan and light gray shaley CLAY, jointed, w/ gypsum crystals Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:6

40 LOG OF BORING B-5 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/24/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain " ASPHALT Dark gray sandy CLAY mixed with asphalt base (FILL) Dark gray and tan CLAY w/ calcareous nodules and iron stains (FILL) Brown to tan CLAY, jointed, w/ calcareous nodules Tan and light gray shaley CLAY, jointed, w/ calcareous nodules and iron stains bentonite seam at 14.5' Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:7

41 LOG OF BORING B-6 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/25/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain 0 6.5" ASPHALT Lime-Treated CLAY (FILL) Dark brown CLAY, jointed, w/ calcareous nodules Dark brown and brown CLAY, jointed, w/ calcareous nodules Tan CLAY, jointed, w/ calcareous deposits and iron stains Tan shaley CLAY, jointed Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:8

42 LOG OF BORING B-7 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/25/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain 0 7.5" ASPHALT Lime-Treated CLAY (FILL) Dark brown CLAY, jointed, w/ calcareous nodules Brown CLAY, jointed, w/ calcareous nodules and iron stains Tan and gray CLAY, jointed, w/ calcareous deposits Gray and tan shaley CLAY, blocky, jointed, w/ iron stains and bentonite seams Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:9

43 LOG OF BORING B-8 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/24/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain " ASPHALT over 2.5" BASE Lime-Treated CLAY (FILL) Tan CLAY w/ calcareous nodules and gypsum crystals (FILL) Tan and light gray shaley CLAY, jointed, w/ iron and sulfur lenses (FILL) Light gray to gray and tan CLAY, jointed, w/ sulfur and iron deposits, and sand seams Gray shaley CLAY, jointed w/ iron deposits Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:10

44 LOG OF BORING B-9 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/20/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain 0 8" CONCRETE over asphalt BASE Dark gray and tan CLAY w/ calcareous nodules and iron stains (FILL) Dark gray to dark brown CLAY, jointed, w/ calcareous nodules and iron stains Brown and tan CLAY, jointed, w/ calcareous nodules Tan and light gray shaley CLAY, jointed Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:11

45 LOG OF BORING B-10 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/20/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain 0 2.5" ASPHALT over 7.5" CONCRETE Asphalt BASE Dark gray and tan CLAY (FILL) Dark gray CLAY, jointed, w/ calcareous nodule large gravel pieces at 7.5' Brown and tan CLAY, jointed, w/ calcareous nodules Boring terminated at 15' Notes: Alliance Geotechnical Group, Inc. FIGURE:12

46 LOG OF BORING B-11 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/20/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: Dry Depth to water when checked: was: Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain " CONCRETE Cement-Treated SAND Brown CLAY (FILL) Dark brown to brown CLAY, jointed, w/ calcareous nodules Tan CLAY, jointed, w/ calcareous nodules and organics Tan shaley CLAY, jointed, w/ calcareous nodules and deposits Bentonite seam at 11' Boring terminated at 15' Notes: FIGURE:13 Alliance Geotechnical Group, Inc.

47 LOG OF BORING B-13 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/23/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: 22.5' Depth to water when checked: end of day was: 19.8' (16' during drilling) Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain 0 9" CONCRETE Cement-Treated SAND Tan, brown and dark gray CLAY w/ calcareous nodules (FILL) /6" 5/6" Tan CLAY, jointed, w/ calcareous nodules /6" 9/6" /6" 9/6" Tan and light gray shaley CLAY, jointed, blocky, w/ calcareous deposits water seepage at 16' during drilling 20 7/6" 11/6" /6" 40/6" -w/ gypsum crystals at 24' Boring terminated at 25' Notes: Alliance Geotechnical Group, Inc. FIGURE:15

48 LOG OF BORING B-14 Project: DFW Airport - Rehab SW Construction Road, 31st St, 32nd St & 33rd St Project No.: DE Date: 04/23/2018 Elev.: Location: See Figure 1 Depth to water at completion of boring: 22.5' Depth to water when checked: end of day was: 19.8' (13' during drilling) Depth to caving when checked: was: ELEVATION/ DEPTH (feet) SOIL SYMBOLS SAMPLER SYMBOLS & FIELD TEST DATA DESCRIPTION MC LL PL PI -200 DD pcf P.PEN tsf UNCON ksf Strain " CONCRETE over 1.5" Cement-Treated SAND Brown and tan CLAY (FILL) Dark gray to brown and tan CLAY w/ large gravel pieces (FILL) /6" 4/6" /6" 8/6" Dark gray CLAY, jointed, w/ calcareous nodules /6" 6/6" Tan CLAY, jointed, w/ sand seams and calcareous nodules -water seepage at 13' during drilling /6" 12/6" Tan and light gray shaley CLAY, jointed, blocky, w/ iron deposits /6" 33/6" Boring terminated at 25' Notes: Alliance Geotechnical Group, Inc. FIGURE:16

49 Symbol Description KEY TO LOG TERMS & SYMBOLS Symbol Description Strata symbols CONCRETE Water table at boring completion Soil Samplers Lime-Treated CLAY Rock Core CLAY Thin Wall Shelby Tube CLAY, shaley Auger Asphaltic Paving THD Cone Penetration Test CLAY, sandy Cemented SAND SHALE Misc. Symbols Water table when checked Notes: 1. Exploratory borings were drilled on dates indicated using truck mounted drilling equipment. 2. Water level observations are noted on boring logs. 3. Results of tests conducted on samples recovered are reported on the boring logs. Abbreviations used are: DD = natural dry density (pcf) LL = liquid limit () MC = natural moisture content () PL = plastic limit () Uncon.= unconfined compression (tsf) PI = plasticity index P.Pen.= hand penetrometer (tsf) -200 = percent passing # Rock Cores REC = (Recovery) sum of core sample recovered divided by length of run, expressed as percentage. RQD = (Rock Quality Designation) sum of core sample recovery 4" or greater in length divided by the run, expressed as percentage. Alliance Geotechnical Group, Inc. FIGURE:17

50 SWELL TEST RESULTS BORING NO. DEPTH (FEET UNIT WEIGHT (pcf) ATTERBURG LIMITS LL PL PI IN-SITU MOISTURE CONTENT FINAL MOISTURE CONTENT LOAD (psf) VERTICAL SWELL B B B-3A B , B , B , B , B B , B B B , B , PROCEDURE: 1. Sample placed in confining ring, design load (including overburden) applied, free water with surfactant made available, and sample allowed to swell completely. 2. Load removed and final moisture content determined. SWELL TEST RESULTS REHAB SW CONSTRUCTION ROAD, 31 ST ST, 32 ND ST & 33 RD ST DFW AIRPORT, TEXAS ALLIANCE GEOTECHNICAL GROUP DE Date: 05/22/2018 FIGURE 18

51 SOLUBLE SULFATES TEST RESULTS (PPM) BORING NO. DEPTH SOLUBLE SULFATES (PPM) B ,540 B B <100 B-3A 1-2 <100 B <100 B <100 B <100 B-7 B < ,400 B <100 B B <100 B-12 B , < , , ,600 B <100 SOLUBLE SULFATES TEST RESULTS REHAB SW CONSTRUCTION ROAD, 31 ST ST, 32 ND ST & 33 RD ST DFW AIRPORT, TEXAS ALLIANCE GEOTECHNICAL GROUP DE DATE: 05/22/2018 FIGURE: 19

52 LIME SERIES RESULTS BORING NO. DEPTH (FEET) LIME ADDED () LIQUID LIMIT () PLASTICITY INDEX (PI) B B B LIME SERIES RESULTS REHAB SW CONSTRUCTION RD, 31 st ST, 32 nd ST & 33 rd ST DFW AIRPORT, TEXAS ALLIANCE GEOTECHNICAL GROUP DE DATE: 05/21/18 FIGURE: 20

53 COMPACTION TEST REPORT , 97.7 pcf Dry density, pcf ZAV for Sp.G. = Water content, Test specification: Miniature Harvard Compaction Test Elev/ Classification Nat. > < Sp.G. LL PI Depth USCS AASHTO Moist. #4 No.200 Maximum dry density = 97.7 pcf Optimum moisture = 26.3 TEST RESULTS Project No. DE Client: DFW Airport Remarks: Project: SW Construction Rd., 31st St, 32nd St, 33rd St Date: 5/15/18 Location: B-1 2'-6' Alliance Geotechnical Group, Inc MATERIAL DESCRIPTION Dark gray and brown Clay with tan and light gray Shaley Clay (FILL) Dallas, TX Figure 21 Tested By: BV Checked By: JP

54 COMPACTION TEST REPORT , 97.3 pcf Dry density, pcf ZAV for Sp.G. = Water content, Test specification: Miniature Harvard Compaction Test Elev/ Classification Nat. > < Sp.G. LL PI Depth USCS AASHTO Moist. #4 No TEST RESULTS MATERIAL DESCRIPTION Maximum dry density = 97.3 pcf Dark gray and brown Clay (FILL) Optimum moisture = 23.1 Project No. DE Client: DFW Airport Remarks: Project: SW Construction Rd., 31st St, 32nd St, 33rd St Date: 5/15/18 Location: B-3 2'-5' Alliance Geotechnical Group, Inc. Dallas, TX Figure 22 Tested By: BV Checked By: JP

55 COMPACTION TEST REPORT , 98.9 pcf Dry density, pcf ZAV for Sp.G. = Water content, Test specification: Miniature Harvard Compaction Test Elev/ Classification Nat. > < Sp.G. LL PI Depth USCS AASHTO Moist. #4 No TEST RESULTS MATERIAL DESCRIPTION Maximum dry density = 98.9 pcf Dark gray and tan Clay (FILL) Optimum moisture = 23.6 Project No. DE Client: DFW Airport Remarks: Project: SW Construction Rd., 31st St, 32nd St, 33rd St Date: 5/15/18 Location: B-5 2'-6' Alliance Geotechnical Group, Inc. Dallas, TX Figure 23 Tested By: BV Checked By: JP

56 COMPACTION TEST REPORT , 96.5 pcf Dry density, pcf ZAV for Sp.G. = Water content, Test specification: Miniature Harvard Compaction Test Elev/ Classification Nat. > < Sp.G. LL PI Depth USCS AASHTO Moist. #4 No.200 Maximum dry density = 96.5 pcf Optimum moisture = 24.9 TEST RESULTS Project No. DE Client: DFW Airport Remarks: Project: SW Construction Rd., 31st St, 32nd St, 33rd St Date: 5/15/18 Location: B-10 2'-5' Alliance Geotechnical Group, Inc MATERIAL DESCRIPTION Dark gray and tan Clay (FILL) Dallas, TX Figure 24 Tested By: BV Checked By: JP

57 COMPACTION TEST REPORT , 94.1 pcf Dry density, pcf ZAV for Sp.G. = Water content, Test specification: Miniature Harvard Compaction Test Elev/ Classification Nat. > < Sp.G. LL PI Depth USCS AASHTO Moist. #4 No.200 Maximum dry density = 94.1 pcf Optimum moisture = 24.5 TEST RESULTS Project No. DE Client: DFW Airport Remarks: Project: SW Construction Rd., 31st St, 32nd St, 33rd St Date: 5/15/18 Location: B-13 2'-7' Alliance Geotechnical Group, Inc. 2.7 MATERIAL DESCRIPTION Dark gray, tan and brown Clay (FILL) Dallas, TX Figure 25 Tested By: BV Checked By: JP

58 RECOMMENDED SLOPE RATIOS Short Term (under 8 hours) Long Term (over 8 hours) SOIL / ROCK H V H V Fill soils, sand, gravel, clayey sand, very sandy clay, and/or soft clayey soils or soft sandy clay soils (hand penetrometer of 0.5 to 0.9 tsf) Submerged soils from which water is seeping * Stiff to hard clay and shaley clay and weathered shale above existing groundwater level * In accordance with the best interpretation of OSHA regulations, submerged soil is defined as water bearing granular soils, fissured clay soils, or fractured rock (jointed, fractured weathered shale or fractured gray shale) from which groundwater is seeping. NOTE: Recommended slope ratios may be subject to reduced stability under the influence of groundwater or saturation by rain. Recommended slope ratios are designed for safety only of temporary excavations and are not designed to prevent limited sloughing during construction. REHAB SW CONSTRUCTION RD, 31 ST ST, 32 ND ST & 33 RD ST DFW AIRPORT, TEXAS RECOMMENDED SLOPE RATIOS PROJECT NO: DE FIGURE 26

59 LATERAL EARTH PRESSURES FOR INTERNALLY BRACED EXCAVATIONS s h = k g H WHERE: s h = Lateral Earth Pressure, psf. g = Saturated Unit Weight of Soil Use 130 pcf H = Height of Excavation, ft. k = Earth Pressure Coefficient; Use 0.35 NOTES: 1) If water is not allowed to drain from behind shoring or bracing, full hydrostatic pressure must be considered. 2) Surcharge loads and traffic live loads, if present, must also be considered. SW CONSTRUCTION RD, 31 ST ST, 32 ND ST, 33 RD ST DFW AIRPORT, TEXAS LATERAL EARTH PRESSURES PROJECT NO: DE Figure 27

60 APPENDIX A MEASURES TO MINIMIZE DEEP SEATED SWELL In order to reduce the risk of excessive upward ground movements caused by soil swelling associated with free water sources, the following measures should be taken during design and construction: The use of superior contractors and utility line materials accompanied with Quality Control inspection and testing of all utility line installations. Utility under-drains with impervious barriers along the trench bottom may be used as an additional safeguard to minimize post-construction upward movement caused by water percolation into the deeper clay soils. Positive drainage should be provided. Surface drainage gradients within 10 feet of the pavement should be constructed with maximum slopes allowed by local codes. Rapid repair of any utility leak including water lines, sewer lines, and storm drains. Trees and deep rooted shrubs should be located no closer to the pavement than their ultimate mature height (and to greater distances were multiple trees are present and/or when the ground beneath the drip lines are paved) to reduce foundation settlement effects caused by moisture absorption of the root systems. It is imperative that all cracks and joints in the pavement be sealed and maintained by routine sealing in order to minimize differential pavement deflections caused by soil swelling. It is important that porous fill soils (sandy soil) not be used as backfill behind the curbs or as leveling sand below pavements to prevent ponding beneath the pavement or near the curb line. ALLIANCE GEOTECHNICAL GROUP DE18-047

61 APPENDIX B PAVEMENT CORES Existing Pavement Thickness Summary Area Boring No. Asphalt (in) Concrete (in) Comments B Over Lime-Treated Clay B Over Lime-Treated Clay B-3 8 Over Lime-Treated Clay SW Construction Rd B-3A 8.25 Over Lime-Treated Clay B-4 8 Over Lime-Treated Clay B Over Sandy Clay B Over Lime-Treated Clay B Over Lime-Treated Clay B Over 2.5 Base over Lime-Treated Clay B-9 8 Over Asphaltic Base 31 st St 2.5 Asphalt over 7.5 Concrete over B Asphaltic Base 32 nd St B Over Cement-Treated Sand B Over Lime-Treated Clay 33 rd St B-13-9 Over Cement-Treated Sand B Over Cement-Treated Sand *The thickness of the pavement cores are based on the average measured length of each respective core.

62 APPENDIX B PAVEMENT CORES BORING B-1

63 APPENDIX B PAVEMENT CORES BORING B-2

64 APPENDIX B PAVEMENT CORES BORING B-3

65 APPENDIX B PAVEMENT CORES BORING B-3A

66 APPENDIX B PAVEMENT CORES BORING B-4

67 APPENDIX B PAVEMENT CORES BORING B-5

68 APPENDIX B PAVEMENT CORES BORING B-6

69 APPENDIX B PAVEMENT CORES BORING B-7

70 APPENDIX B PAVEMENT CORES BORING B-8

71 APPENDIX B PAVEMENT CORES BORING B-9

72 APPENDIX B PAVEMENT CORES BORING B-10

73 APPENDIX B PAVEMENT CORES BORING B-11

74 APPENDIX B PAVEMENT CORES BORING B-12

75 APPENDIX B PAVEMENT CORES BORING B-13

76 APPENDIX B PAVEMENT CORES BORING B-14 *The pavement core in this picture is upside down. The top layer is cementtreated sand.

77 APPENDIX C CATERING TRUCKS & DFW EMPLOYEE BUS SPECIFICATIONS SKY CHEF LARGE CATERING TRUCK

78 APPENDIX C CATERING TRUCKS & DFW EMPLOYEE BUS SPECIFICATIONS SKY CHEF SMALL CATERING TRUCK

79 APPENDIX C CATERING TRUCKS & DFW EMPLOYEE BUS SPECIFICATIONS GATE GOURMET CATERING TRUCK

80 APPENDIX C CATERING TRUCKS & DFW EMPLOYEE BUS SPECIFICATIONS DFW EMPLOYEE BUS Mr. Douglas Rogers (DFW Airport s Parking Department) provided this bus specification sheet for a previous DFW Airport project. The axle load configuration was used to perform the pavement analyses for this project.

81 APPENDIX C CATERING TRUCKS & DFW EMPLOYEE BUS SPECIFICATIONS Page 1 of 3

82 APPENDIX C CATERING TRUCKS & DFW EMPLOYEE BUS SPECIFICATIONS Page 2 of 3