Report No A. Prepared for

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1 Testing, Development and Research th Street North Clearwater, Florida ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO. 224 TAMPA BAY AREA (727) FLORIDA CFTL FAX (727) LASER EYE CLINIC 3200 N. McMullen Booth Road, Clearwater Parcel: Pinellas County, Florida Geotechnical Services December 2017 Report No A Prepared for Brandon Construction Company Mr. Robert J. Carr, Vice President 555 Palm Harbor Boulevard (Alt. 19) Palm Harbor, Florida 34683

2 Testing Development and Research TH STREET NORTH CLEARWATER, FL ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO. 224 TAMPA BAY AREA (727) FLORIDA CFTL FAX (727) December 22, 2017 Mr. Robert J. Carr, Vice President Brandon Construction Company 555 Palm Harbor Boulevard Palm Harbor, Florida Re: Supplemental Geotechnical Investigation of Proposed Laser Eye Clinic Building at 3200 North McMullen Booth Road, Clearwater, Florida CFTL Report No A Dear Mr. Carr: As authorized, our office conducted a supplemental subsurface soils investigation for the above referenced project. This investigation consisted of three additional standard penetration test (SPT) borings to supplement the previous five SPT borings conducted for this project. The locations of all three supplemental borings along with the previous five borings, hand auger borings and double ring infiltration test are shown on the attached enlarged aerial photograph of the subject property. As can be seen in this aerial, the proposed building footprint has been overlaid onto the aerial photo. The exact location of the new building was not known at the time the five previous borings were performed. The first two supplemental borings, labeled SB-1 and SB-2, are within the footprint of the building as is our previous boring B-1. The remaining previous four borings, B-2, B-3, B-4 and B-5, are outside the footprint of the new medical office building. The third supplemental boring labeled PB-1 is located within the proposed retention pond in the southwest portion of the site. The results of the three hand auger borings and DRI test were reported under our Lab No , dated November 27, That report should be reviewed for its findings. Again, for additional reference to the subject property, we are including an area map showing the location of the site with respect to the surrounding geographical area, large and small scale aerial photographs of the property, and a FIRM (Flood Insurance Rate Map) map which provides the FEMA Flood Zoning of the subject property. Based on this map the property is zoned by FEMA as X with no specific flood zoning requirements associated with it. We suggest however, that either the Pinellas County Building Department or the City of Clearwater Building Department be consulted to confirm the FEMA zoning and all building requirements for this site.

3 Brandon Construction Company Supplemental Geotechnical Investigation for Laser Eye Clinic Bldg. CFTL Report No A Page 2 The purpose of this supplemental investigation was to provide soil profiles within the specific building footprint for comparison to the profiles of our previous borings and to determine if a change to the recommendations previously presented is warranted. Site Description The site is located on the west side of McMullen Booth Road south of Curlew Road, across from Mease Countryside Hospital in Clearwater, Florida. The property is the southern portion of the overall parcel owned by Holy Trinity Episcopal Church, which sits on the north side of a small pond that is positioned between the site and the existing church building. Access is available off of a paved entrance that connects to McMullen Booth Road. Briar Creek borders the south side of the site and runs beneath McMullen Booth Road to the east. Three existing structures consisting of an active Thrift Shop associated with the church are still present and operating on the property. The subject property is bordered by Landmark Place condominiums on the west, Briar Creek on the south, McMullen Booth Road on the east, and Holly Trinity Episcopal Church on the north. It is still our understanding that the new structure will be a two (2) story medical facility; however, its location has been determined and is shown by the overlay on the aerial photo of the site. Test Methods The supplemental borings were done using sampling intervals in excess of those required by ASTM Specifications, D-1586, describing the Standard Penetration Test or "split-spoon" method of sampling. Four samples were taken in the upper ten feet to provide greater definition within this zone. The penetration resistance testing and sample taking was accomplished with the use of a 2" O.D. sampler seated six inches into the bottom of the bore hole and advanced an additional one foot under the effort of a 140 pound hammer falling freely thirty inches. The number of blows required of the hammer to advance the sampler one foot into undisturbed material was noted as the blow count (N) of that particular stratum. Portions of each soil sample so taken, were classified, sealed in moisture-proof containers and returned to our laboratories for verification of field classification. The borings were advanced using a rotary drill rig, utilizing a recirculating bentonite drill fluid to maintain the bore hole in noncohesive soils and to remove cuttings created by the drill bit. Upon completion the bore holes were sealed in accordance with SWFWMD

4 Brandon Construction Company Supplemental Geotechnical Investigation for Laser Eye Clinic Bldg. CFTL Report No A Page 3 regulations. Due to encountering potentially active clay soils at relatively shallow depths within SB-1 and SB-2, laboratory testing consisting of Atterberg Limit tests conducted in accordance with ASTM D-4318 were performed on select clay samples. The Plasticity Index (P.I.) of a clay is represented by the difference in moisture content between the Liquid Limit and the Plastic Limit of a clayey soil. Plasticity Indexes above 15 are considered by the Florida Building Code to warrant specific attention by foundation design. Soils with a Plasticity Index (P.I.) less than 10 are considered to represent low plasticity soils; soils with a P.I. between 10 and 30 are considered to represent moderately plastic soils, while soils with a P.I. above 30 are considered to represent highly plastic soils. Moderately to highly plastic clay soils also known as "active" clays are capable of causing damage to a structure by their volume changes (shrinkage/expansion) with changing moisture conditions. Building Boring Results The soil profiles identified by SB-1 and SB-2 borings were generally similar to each other but differed from the profile of boring B-1 which was also within the building footprint. The profile of supplemental borings SB-1 and SB-2 will be described separately. Boring AB-1, located in the northwest corner of the proposed new medical center building, encountered soils composed of approximately 5 feet of loose sands and low plasticity firm clayey sands followed by moderately plastic, soft clays which graded to stiff clay by 10 feet and very hard clay by 15 feet. Below 15 feet and continuing to 30 feet were very stiff clays which again returned to very hard conditions by the termination depth of the boring, 35 feet below the surface. No loss of drilling fluid circulation occurred during the drilling of boring SB-1 and the shallow groundwater table was found to be deeper than 6 feet below the surface when attempted to be measured in a hand auger boring conducted adjacent to the SPT borehole. Atterberg Limit testing of the upper clays in boring SB-1 at a depth of 7 feet below the surface found their Plasticity Indexes to range be 25 which is consistent with those found in boring B-5, the closest previous boring. Boring SB-2, located in the south central portion of the proposed new medical center building, encountered soils composed of 7 feet of variable consistency, loose to slightly loose, sands followed by moderately plastic, stiff sandy clay to 10 feet and hard clays below 10 feet to the termination depth of the boring, 35 feet below the surface. Atterberg Limit testing of the sandy clay layer encountered at 7 feet in boring SB-2 record a P.I. of 20. Again, no loss of drilling fluid circulation occurred during drilling of the boring and the shallow water table was deeper than 6 feet below the surface.

5 Brandon Construction Company Supplemental Geotechnical Investigation for Laser Eye Clinic Bldg. CFTL Report No A Page 4 Conclusions Based on the soil profiles defined by the two supplemental borings and in conjunction with the previous five, our recommendations have not changed. The supplemental borings show that the moderately to highly plastic clay soils beneath the building footprint begin at variable depths ranging from approximately 1 foot to 7 feet below the surface. With the shallow water table not encountered to a depth of 6 feet in these recent borings, it is our opinion that fluctuations in the water table between wet and dry seasons will produce moisture changes within the clay soils that can effect a shallow spread footer foundation and cause potential detrimental damage to the building. Our previous report provided some estimates of uplift forces associated with various plasticity clay soils. These still apply. Recommendations Our recommendations previous presented still apply. Please review the previous recommendations for a more detailed description of foundation recommendations. In summary, however, the previous recommendations included a method to address the potential volume change within the upper clayey soils with either (1) a deep foundation be considered for support of the buildings or (2) a modified shallow foundation be designed that will resist the stresses imposed by the shrink/swell forces of the clays and prevent or minimize cracking associated with differential movement. The first recommendation includes a pile foundation consisting of augercast concrete piling installed into soils well below the depth of the fluctuating water table to prevent shrink/swell movement of the clay soils from affecting the building. Based on the boring logs we would recommend that the augercast concrete piling be installed into the refusal hardness clays found beginning approximately 20 to 30 feet below the existing land elevation. Grade beams would be required to isolate and support both the building walls and structural designed floors to prevent differential movement. A void space would be required between the floor slabs and the underlying soils to prevent direct heave forces to be exerted against the floor slab. The void space is typically created with use of a void box made of manufactured corrugated cardboard forms. In lieu of use of a void box the space between the floor slab and the underlying clayey soils can be developed by having a minimum separation of approximately 3 feet between the bottom of the grade beams and floor slab and the upper limit of the active clays using approximately 12 of compacted crushed stone aggregate (FDOT #57 stone) as the lower foot of separation. The void space within the crushed stone will provide adequate relief for expansion of the clays into the crushed aggregate without heaving the overburden soils. The two feet of compacted sand meeting SP classification by the Unified Soil Classification System. This sand zone would be located above the crushed aggregate and should

6 Brandon Construction Company Supplemental Geotechnical Investigation for Laser Eye Clinic Bldg. CFTL Report No A Page 5 be separated from the aggregate by a filter fabric to prevent the sand from migrating into the stone. The compacted sand provides the support for casting the floor slab. The support capacities of typical 12 diameter augercast concrete piling would be up to 40 tons per pile in axial compressive orientation and 20 tons in uplift resistance if installed into the refusal clays well below any fluctuating water table levels. This depth would be determined by lack of advancement of the auger for a prescribed short time period and/or a minimum depth of 20 feet beneath the surface. If this type piling are contemplated for use, please contact our office for additional recommendations. The second recommendation includes the design of a modified shallow monolithic foundation referred to as a mat foundation. This type foundation/slab consists of a thicker than normal floor slab or waffled slab design which also acts as the foundation for the walls. It is heavily reinforced to resist cracking from differential movement associated with the shrinking and swelling of the clayey soils. It would also be separated by a minimum of three feet of distance between it and the underlying active clays using 12 of compacted crushed stone, filter fabric and compacted sand buffer zone discussed above. This approach requires the engineered separation pad to extend a minimum of 3 feet beyond the limits of the mat foundation. The mat foundation may be designed for an allowable soil pressure of 2,000 pounds per square foot. Above Grade Fill Soils For all fill soils placed within the building envelop and above the engineered pad, we recommend they consist of clean, noncohesive sandy soils classified SP by the Unified Soil Classification System. Fill should be placed in lifts not exceeding one foot in depth and compacted to a minimum density of at least ninety-five percent (95%) of the soils maximum dry density as established by the Modified Proctor Test, ASTM D Each lift should achieve satisfactory density results prior to placement and compaction of subsequent lifts to eliminate the possibility of dense soil bridging over loose insufficiently compacted soils. Supplemental Retention Pond Boring Result Boring PB-1 was located in the retention pond in the southwest portion of the site. This boring was advanced to a depth of 20 feet with its profile reflecting approximately 7 feet of loose sandy soils followed by varying consistency clay soils that ranged from firm at 7 feet to very hard at 15 feet below the surface. Again, no loss of drilling fluid circulation occurred during drilling of the boring and the shallow water table was found to be deeper than 6 feet below the surface. The clay soils below 7 feet can be expected to have extremely low permeability rates and will not be able to dissipate infiltration water that enters the pond.

7 Brandon Construction Company Supplemental Geotechnical Investigation for Laser Eye Clinic Bldg. CFTL Report No A Page 6 Limitations This investigation and report deals only with the soil zones and strata located within the area represented from the ground surface to the termination depth of the borings. It is not intended to predict or accept responsibility for sinkhole development. Other means of subsurface investigations including, but not limited to, deep structural borings, rock coring, geophysical studies, ground penetrating radar or resistivity surveys are used for sinkhole potential determinations and are out of the scope of this investigation. Generally accepted soil mechanics and foundation engineering practices were utilized in the preparation of this report; and no other warranty, either expressed or implied is made as to the recommendations provided. This report is for the exclusive use of our client and may not contain sufficient information for other uses, such as quantity take-offs, or for interpretation by other parties for bidding purposes. In the event conclusions and/or recommendations based on our data are made by others, such conclusions and/or recommendations are not our responsibility unless we have been given an opportunity to review and concur with them. If borings were not staked by a registered land surveyor but were located by our drill crews, the following method was used: Distances are generally measured using a 100 foot tape measure with right angle approximation used to turn corners. Scaling from prints or surveys with reference points shown on the plan or geographical references will produce a degree of accuracy that is typically +/- 5% for length and +/- 10 degrees for angles. Soil strata delineations are estimated in the field by color changes, texture differences and penetration resistance values. These may be more gradual transitions than those shown on the boring log representations of strata delineations. The ground water depth determination shown at the bottom of the boring logs was measured in the bore hole at the time of drilling, unless noted otherwise. This depth does not reflect seasonal high water levels and would fluctuate as expected with variations in rainfall or other factors not present at the time of our soils investigation. The boring data represents only that data obtained during this investigation at the approximate locations shown on the site schematic or plan. Should significant variations of soil or subsurface conditions exist between boring

8 Brandon Construction Company Supplemental Geotechnical Investigation for Laser Eye Clinic Bldg. CFTL Report No A Page 7 locations and be encountered by future exploratory work or site preparation efforts, our office should be notified so that supplemental borings or data gathering determinations can be made to update our report and recommendations at a minimal expense to our client. It is the responsibility of our client to inform our office of these variations if possible modifications of the report is warranted. This report is general in nature, unless specific geotechnical data or recommendations were asked to be addressed. However, we would be pleased to answer any questions concerning comments or recommendations made in this report, if warranted. We appreciate the opportunity to have been of service. If any further evaluation of the site or testing services are needed, either prior to or during construction, please do not hesitate to contact our office. Sincerely, CENTRAL FLORIDA TESTING LABORATORIES, INC. George C. Sinn, Jr., P.E. FLN President/Principal Engineer GCS/gs Not for public use unless original signature, date and raised seal are applied. Attachments

9 Project Name: Laser Eye Clinic/3200 N. McMullen Booth Rd. Report No.: A Maps Various

10 Legend Figure 1 - Location MEDICAL OFFICE BUILDING 3200 N. McMullen Booth Road Clearwater, Florida Report No: A Subject Property Population Center Land Sand Woodlands Park Interstate Toll Highway US Highway State Route Local Road Major Connector Water Intermittent Lake Wetland River/Canal Intermittent River Railroad

11 Project Name: Laser Eye Clinic/3200 N. McMullen Booth Rd. Report No.: A 2016 Aerial Photograph of Site

12 Project Name: Laser Eye Clinic/3200 N. McMullen Booth Rd. Report No.: A 2016 Aerial Photograph of Site

13 SB-1 B-1 B-2 SB-2 B-5 B-3 HA-1 B-4 PB-1 HA-3 DRI-1 HA-2 Figure 1 - Site Schematic Tech: A. Ceron Date: & J. Spinks thru Compiled By: J. Darling Checked By: T. Gates Date: Date: CENTRAL FLORIDA TESTING LABORATORIES, INC th Street North * Clearwater, Florida (727) CFTL FAX (727) LASER EYE CLINIC 3200 N. McMullan-Booth Road (Pinellas County, Florida) Approximate Locations of SPT Borings LEGEND B-xx (Denotes SPT Borings) SB-xx (Denotes Supplemental SPT Borings) DRI-xx (Double Ring Infiltration Test) HA-xx (Shallow Auger Boring) CFTL Report No.: A Please Note: Unless Otherwise Indicated - All Boring Locations are Field Located By CFTL, Inc. Using a Hand-Held Global Positioning System (GPS), Currently the Magellan Explorist 610. Locations Staked by Handheld GPS are ONLY Approximate (generally a 3-meter accuracy) and Therefore, Exact Locations May Not be Relied Upon.

14 Project Name: Laser Eye Clinic/3200 N. McMullen Booth Rd. Report No.: A SPT Boring Results SB-1 & SB-2 in Proposed Building/PB-1 in Planned Pond Expansion

15 Client: Brandon Construction Company Project: Laser Eye Clinic Location: 3200 N. McMullen Booth Road City / State: Clearwater, Florida Report No: A Log of Borehole: SB-1 Date Drilled: 12/05/2017 ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO Depth 5 Strata Symbol Ground Surface Sand Gray, fine grained Sand Brown, fine grained ey Sand Brown, fine grained Subsurface Profile Description Consistency loose firm firm Blow Count N value Standard Penetration Test (blows/ft) PI = 10 Lab/ Notes soft Gray stiff Light gray, cemented very hard 50/5" very stiff Light greenish gray and greenish gray very stiff very stiff very hard 50-50/3" 100+ End of Boring 40 Notes: FEMA Flood Zone: X PI = Plasticity Index Drill Method: Rotary Sampling Method: Splitspoon ASTM D-1586 No loss of drill fluid circulation Water Table: >6.0' bls (HA) Ground Elevation: Existing Drilled by: AC/JR Compiled by: PG Sheet 1 of 1

16 Client: Brandon Construction Company Project: Laser Eye Clinic Location: 3200 N. McMullen Booth Road City / State: Clearwater, Florida Report No: A Log of Borehole: SB-2 Date Drilled: 12/04/2017 ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO Depth 5 10 Strata Symbol Ground Surface Sand Gray, fine grained Sand Brown, fine grained Sand Light brown, fine grained Silty Sand Light gray, fine grained Subsurface Profile Description Light greenish gray, with gray sand seams Consistency loose slightly loose slightly loose stiff very hard Blow Count /4" N value Standard Penetration Test (blows/ft) PI = 20 Lab/ Notes Light greenish gray, cemented 15 hard Greenish gray hard hard Pale brown and greenish gray 30 very hard /5" 100+ Pale brown, cemented 35 End of Boring hard Notes: FEMA Flood Zone: X PI = Plasticity Index Drill Method: Rotary Sampling Method: Splitspoon ASTM D-1586 No loss of drill fluid circulation Water Table: >6.0' bls (HA) Ground Elevation: Existing Drilled by: AC/JR Compiled by: PG Sheet 1 of 1

17 Client: Brandon Construction Company Project: Laser Eye Clinic Location: 3200 N. McMullen Booth Road City / State: Clearwater, Florida Report No: A Log of Borehole: PB-1 Date Drilled: 12/04/2017 ENGINEERING BUSINESS NO GEOLOGY BUSINESS NO Depth Strata Symbol Ground Surface Subsurface Profile Description Consistency Blow Count N value Standard Penetration Test (blows/ft) Lab/ Notes Sand Brown (10YR 5/3), fine grained loose very loose very loose Pale brown (10YR 6/3) firm Light greenish gray (5G 7/1) hard Greenish gray (10GY 6/1), cemented very hard Greenish gray (5G 6/1) hard End of Boring Notes: NRCS Designation: Pitts NRCS SHGWT: Variable CFTL SHGWT: Not distinguishable Drill Method: Rotary Sampling Method: Splitspoon ASTM D-1586 No loss of drill fluid circulation Water Table: >6.0' bls (HA) Ground Elevation: Existing Drilled by: AC/JR Compiled by: PG Sheet 1 of 1