SECTION EXCAVATING, BACKFILLING AND COMPACTING

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1 SECTION EXCAVATING, BACKFILLING AND COMPACTING PART 1 GENERAL 1.1 DESCRIPTION A. Provide excavation, overexcavation, fill, backfill and compaction for areas under buildings and structures shown on the drawings and specified as required to complete the work. Include preparation of subgrade of slabs,walks and driveways adjacent to the building and structures. Also, include trenches and underground utilities within and adjacent to the buildings and structures. B. Related Sections: The following sections contain requirements that relate to this section: 1. Section Soil Treatment 2. Section Paving and Surfacing 1.2 SUBSURFACE CONDITIONS A. The geotechnical report for the project is available from the Architect. 1. A report prepared by Andreyev Engineering, Inc, dated July, 7, PRECONSTRUCTION CONFERENCE A. Prior to commencing work meet at project site with Architect and his consultants, Owner, Contractor and other concerned parties to identify foreseeable problems and plan coordination of involved operations. 1.4 EXPLORATION A. Prior to opening an excavation initiate research to determine whether underground sewer, water, fuel, electric lines and other installations will be encountered and, if so, where such are located. Inform known owners of underground facilities in the area involved of proposed work minimum 48 hours before commencing actual excavation. When excavation approaches the approximate locations of such facilities, determine their exact locations by careful probing or hand digging. When facilities are uncovered provide proper and adequate protection thereof. EXCAVATING,BACKFILLING AND COMPACTING

2 B. The contractor shall obtain a dig permit from Physical Plant Division (PPD) prior to commencing any excavation or grading. Initial utilities location is done free of charge. For large projects this may be done in areas. Relocations will be charged. 1.5 UTILITIES The dig permit, which includes the locating of known underground utility lines, is a service provided by the University that is intended to aid the contractor. The contractor remains responsible for any and all expenses associated with the repair of utility lines damaged by the contractor and is responsible to fully restore all landscape features such as pavement markings, turf, mulch, trees, shrubs, curbs, sidewalk, roads and irrigation to original condition. Successful completion of the dig permit process by the contractor in no way transfers any responsibility or liability for the contractor's actions to the University. A. Underground: Remove abandoned lines from within building area and replace with compacted fill. Plug or cap terminations of lines in a safe and sanitary manner. Should unforeseen utilities be encountered that interfere with construction operations immediately discontinue work, inform Architect and obtain instructions. B. Existing: Do not interrupt existing utilities serving facilities used by Owner or others except when authorized by Architect in writing. Provide acceptable temporary service(s) when necessary to interrupt existing service(s) other than at times acceptable to Owner. C. Reporting: During excavating, when a break, leak or other damage is made or discovered to a utility line, its coating or cathodic protection immediately report such to the utility concerned. D. Outages: Utility outages shall be handled in accordance with PPD's Outage Procedure. The Project Manager is responsible for contacting PPD's Work Management Center ( ) prior to necessary outages. E. Utility Connections: All connections to utility systems require submission of a Utilities Service Request (USR) to PPD's Work Management Center. The USR must be approved prior to connection. F. All underground piping and electrical systems must be inspected by PPD systems before backfilling. Requests for PPD inspections must be made by the Contractor at least 24 hours in advance. EXCAVATING,BACKFILLING AND COMPACTING

3 G. Temporary Utilities: The project Contractor shall request temporary utilities by submitting a PPD Utilities Services Request (USR) to PPD's Work Management Center. No connection shall be made until the USR has been approved. 1.6 PROTECTION A. Open trenches are hazardous and unsightly. All trenches should be filled, compacted and permanently resurfaced within one week of trench digging. It is the contractor's responsibility to install and maintain all safety barricades, and to protect the public complying with OSHA requirements. Contractor shall meet the requirements of Section , F.S., Trench Safety Act. Backfilling and compaction shall meet applicable ANSI/ASTM standards. B. Shore and brace or slope sides to angle of repose as necessary to provide safe conditions for workmen and work in progress. Protect and underpin existing utility lines, structures, traffic signage and equipment from damage or displacement. Protect graded areas from rutting by traffic or erosion by wind and water. C. Where excavation is deeper than 20 ft. or other foundation is nearby submit a Florida registered professional civil engineer's analysis of condition and design of shoring or determination of sideslope. 1.7 CONTROLS A. Establish and maintain grade stakes and other necessary control devices in locations where they will be protected from displacement by this work. 1.8 COORDINATION WITH PAVING A. At paved areas do not compact subgrade until completion of installation of underground piping and utilities, including backfilling. If compacting and stabilizing is necessary earlier (to provide access to the work area), recompact and test immediately prior to placing base course of pavement. 1.9 QUALITY ASSURANCE B. Codes and Standards: Perform earthwork in compliance with applicable requirements of governing authorities having jurisdiction. EXCAVATING,BACKFILLING AND COMPACTING

4 C. Testing and Inspection Service: The Contractor shall employ and pay an independent testing laboratory to perform a soil survey for satisfactory soil materials, sampling, and testing soil materials proposed for use in the work, and field testing and quality control during earthwork operations. D. Test for Proposed Materials: 1. Test soil materials proposed for use in the work and promptly submit test result reports. 2. Provide one optimum moisture-maximum density curve for each type of soil encountered in subgrade and fills under building slabs and foundations and paved areas. Determine maximum densities in accordance with ASTM D 1557 and ASTM D 4523, as applicable. 3. Fill Material: Perform a mechanical analysis AASHTO T88 plasticity index, AASHTO T91; moisture-density curve, AASHTO T180 or ASTM D SUBMITTALS A. Test Reports; Submit two (2) copies of each test required. B. Manufacturer s literature for vibratory compaction equipment. C. Testing Laboratory Reports: 1. Stating that material for fill meets requirements. 2. Stating optimum moisture content and maximum dry density obtainable. 3. Stating results of field compaction tests SUPPLEMENTAL AND EXCESS MATERIALS B. Provide (furnish and install) materials as required to accomplish earthwork indicated. Remove all excess and unacceptable materials, debris, trash and the like from the site and dispose of in a legal manner JOB CONDITIONS EXCAVATING,BACKFILLING AND COMPACTING

5 A. Protect structures, utilities, sidewalks, pavements and other facilities from damages caused by settlement, lateral movement, underminimg, washout and other hazards created by excavation operations. PART 2 - PRODUCTS 2.1 MATERIALS A. Backfill and Fill Material: Clean, free-draining sand, max. 12% 10% passing the 200 mesh sieve, free from organic material. (Unified Soil Classification of SP or SP-SM). 1. Rock: Fine to medium coarse (maximum 2 inches) crushed limerock for pavement base.(not to be used as building fill). B. Explosives: Do not use explosives on site. C. Lumber (forms, sheeting, stringers, braces, wales, struts and the like): Southern pine, grade No. 2; Douglas fir, construction grade. D. Porous fill: Same material as Backfill and Fill Material. 2.2 VIBRATORY COMPACTION EQUIPMENT A. Vibratory Rollers: The vibratory drum roller shall have the following minimum requirements: 1. Drum Roller 60-inches minimum 2. Static drum weight or at least 10 tons. 3. Compaction equipment shall be approved by the Architect prior to start of compaction operations. 4. Vibratory roller shall not be used with 30 feet of existing structures. PART 3 - EXECUTION 3.1 INSPECTION OF CONDITIONS EXCAVATING,BACKFILLING AND COMPACTING

6 A. Inspect locations and conditions under which earthwork will be performed. Do not proceed until unacceptable conditions have been corrected. Commencing work will be held as acceptance of conditions. 3.2 PREPARATORY WORK A. Have engineering testing laboratory prepare a moisture density graph of fill material showing optimum moisture content for maximum density in accordance with ASTM D-1557, Method A, and plasticity index. 3.3 STRIPPING A. Clear and grub the entire building area to at least 5 feet beyond perimeter or footings and foundation to remove stumps, roots, trees, vegetation, organic materials, pavement, limerock base, rubble and other obstructions to the work. Grub out all roots larger than ¼ inch in diameter, matted roots and other organic material to at least 24 inches below existing surface. Remove rubble to a minimum of 12 inches below bottom of footings and slabs. B. Disposal: Remove from the site materials not suitable to reuse. C. Following stripping operations and general building pad grading, the proposed construction areas should be proofrolled using a loaded dump truck. Any areas that rut or deflect excessively during the proofrolling shall be removed and replaced with acceptable, compacted back fill. A qualified geotechncial engineer or engineering technician working under the direction of a geotechnical engineer shall witness and document the proofrolling operations. 3.4 COMPACTING A. General: Compact all fill and backfill to the same density as adjacent in-place material as stated below. B. Subgrade: Densify the exposed subgrade using a compactor. C. Compaction Area: Compact the building area and to 5 feet beyond construction lines and paved areas to 5 feet beyond pavement boundaries. D. Compaction of building pad up to and including area 5 feet outside the building line: Under Foundation: See Geotechnical Report for recommendations. EXCAVATING,BACKFILLING AND COMPACTING

7 E. Compaction Under Floor Slabs: Exposed soil beneath floor slabs shall be compacted using a vibratory roller making at least 12 passes in each direction. The uppermost 12-inches shall be compacted to a minimum density of 95% of ASTM D F. In areas to be paved compact soil to one foot below the compaction surface to 95 percent density except uppermost 12 inches shall be 98 percent of maximum dry density at within 2% optimum moisture content as determined by the modified Proctor compaction test; Limerock Bearing Ratio minimum 12.5 and Florida Bearing Value minimum 25. G. Percentage of Maximum Density Requirements: Compact soils too not less than the following percentages of Modified Proctor maximum dry density, ASTM D Existing Subgrades Under Structures; Compact subgrade inches below proposed slab-on-grade and foundations existing grade to 95% maximum density within 2% at optimum moisture. 2. Fill and Backfill Under Foundations: Compact each layer of fill and backfill to 95% maximum density within 2% at optimum moisture. 3. Walkways, Steps and Pavements: Compact top 12-inches of subgrade and each layer of fill or backfill to 98% maximum density within 2% at optimum moisture. H. Compacting: Make 6 complete passes of the area; half along each major axis. Operate compactor at a rate equal to or greater than the resonant frequency and at such rate of travel (generally, between 88 and 176 ft. per minute) as will produce the greatest density. Overlap adjacent paths by approx. 1/6 of the roller width. Do not work where water is within one ft. of the exposed surface. Exercise care to avoid damaging underground utilities and displacing bench marks, grade stakes and other control devices. I. Test each 2,500 sq. ft. of compaction areas (subgrade, each lift of fill and backfill) and each 50 lineal feet of footing trench and each column location in accordance with ASTM D2422 (Nuclear Method), ASTM D-2937 (drive cylinder method) or ASTM D-1556 (sand cone method). 1. Two copies of test reports shall be transmitted directly from the laboratory to the Architect. 2. Test reports shall be identified by the project title, Architects commission number, project location and location and depth of EXCAVATING,BACKFILLING AND COMPACTING

8 each on-site test submitted. J. Elsewhere: Outside of building and paved areas compact soil to 90 percent of maximum density. 3.5 FILLING AND COMPACTING A. After acceptance of sub-surface compaction place fill in uniform lifts of 12 inches (loose measure). Where small compactor is used lifts shall be maximum 6 inches thick. Compact each lift to 95 percent of the maximum modified Proctor density using same compactor as for subsurface compaction, except immediately adjacent to new concrete columns and walls use manually operated, walk behind vibrating plate tamper or small drum roller. Add water to soil as necessary to facilitate compaction. Perform subgrade compaction tests. 3.6 EXCAVATING A. General: Excavate to the necessary depth and size for footings, foundations, piping, conduits, slabs on soil and a minimum distance beyond building lines to permit placing and removal of forms, inspection and the like. If necessary to prevent sides from sloughing or caving cut the excavation in width to clear work required with sides cut to angle of repose or sheet piled. Level bottom of excavations to within 1/2 inch in 10 ft. and clear of loose foreign matter. 2. Trenching: Excavate for piping and conduits by open cut. Make bottom of excavations wide enough to allow approx. 8 inches clearance on both sides of pipe/conduit; bottoms straight (to accurate grade and shape to provide firm uniform bearing for as nearly full length of pipe section as practical). After grading bottom of trench, dig bell holes no larger than necessary to permit joining. 3. Diking: Use soil from excavation to form temporary dikes around the excavation and shape so as to divert surface water away from the excavation. 4. Undercutting: Provide over excavation under footings as recommended in geotechnical report. E. D Unauthorized Excavation Corrective Work: Should unauthorized excavation be made below the indicated elevation, restore to the indicated elevation by the procedure specified for filling and compacting or fill with concrete where ducts are so encased, without extra compensation. EXCAVATING,BACKFILLING AND COMPACTING

9 F. E Extra Work: Where additional excavation is ordered to remove unsuitable material the contract sum will be adjusted to cover such additional work. G. F Disposal: Remove surplus and unsuitable soil, debris, stumps, roots, utilities, trash and other materials resulting from excavation operations from site and dispose of in a legal manner. H. G Groundwater Control:Construct trench and sumps when groundwater seepage and surface water runoff can be collected and controlled by pumping. Maintain foundation construction in a dry condition throughout construction. If groundwater is encountered it shall be maintained at least two feet below construction level (bottom of footings and slabs) at all times. Groundwater drawdowns of two to three feet, if required, shall be achieved by providing temporary perimeter drainage ditches, four to six feet in depth and graded to flow to sumps and remove by pumping. I. H Removal of Unsuitable Materials: Remove all debris and unsuitable soil materials within building, paving and fill areas. Organic materials in the areas shall be excavated and removed from the site. Excavation operations shall be monitored by the testing laboratory technician to verify that loose soil, debris and organic materials are completely removed and minimize excavation of underlying acceptable soils. Replace with satisfactory compacted soil. 3.7 BACKFILLING A. Preparatory Work: Before commencing backfilling remove trash, debris and determine that utilities lines have been inspected, tested, approved and locations recorded. B. Placing: At pipes and conduits deposit initial backfill symmetrically on both sides of pipes and conduits in layers 6 to 8 inches deep below haunches and until at least 3/4 of the depth of the pipe has been reached. C. Compacting: Within building lines compact each layer of fill to 95 percent of maximum density. Where bottom of trench is not shaped to contour of pipe deposit fill below haunches and compact to 95 percent of maximum density. Sand backfill should be compacted in layers to 12 inches above pipe. Thereafter, place backfill around foundation excavations and in plumbing and electrical trenches in lifts of 12 inches (loose measure) and compact each using manually operated "walk behind" mechanical vibratory plate tamper or small drum roller. Where below pavement and 5 ft. beyond, compact to 95 percent of maximum density. Outside of building and paved areas compact soil EXCAVATING,BACKFILLING AND COMPACTING

10 to 90 percent of maximum density. Where compacting backfill against newly constructed ducts and other concrete exercise care to avoid damaging such work. 3.8 CORRECTION OF DEFICIENT COMPACTION A. Should compaction fail to meet the specified density when tested, additional work shall be performed and the area retested, as directed by Architect, at no additional cost to Owner. 3.9 GRADING A. Subgrades: Where concrete slabs occur establish finish surfaces of subgrade at proper elevation to accommodate thickness of floor construction indicated and level to within 1/2 inch in 10 feet (not cumulative). Where pavement occurs establish surface of subgrade below finished surface within 1/2 inch of indicated thickness of pavement (and base if required). B. Finish: Grade to elevations indicated within 0.1 ft. and within one inch in 10 ft. Grade uniformly (visually detectable) between station point elevations and to meet existing grade. Unless indicated otherwise on the drawings, slope surface 1/2 inch per foot 8 to 10 ft. away from the building CLEANING A. Remove trash, debris, excess and unsuitable materials from the site as they accumulate RESTORATION OF SURFACE 1. Should worked areas settle, erode, become rutted or disturbed by subsequent construction or during warranty period, rework and restore to specified condition STORAGE OF SOIL MATERIALS A. Stockpile excavated materials acceptable for backfill and fill materials, including acceptable borrow materials. Stockpile soil materials without intermixing. Place, grade, and shape stockpiles to drain surface water. Cover to prevent wind-blown dust. Stockpile soil materials away from edge of excavations. Do not store within drip line of remaining trees. END EXCAVATING,BACKFILLING AND COMPACTING