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HomeMy WebLinkAbout31 20 00 - Earth MovingMidtown West 17070 Carmel, Indiana September 15, 2017 SECTION 31 20 00 - EARTH MOVING-BUILDING PART 1 - GENERAL 1.1 SUMMARY A. Section Includes: 1. Preparing subgrades for slabs-on-grade. 2. Excavating and backfilling for buildings and structures. 3. Drainage course for concrete slabs-on-grade. 4. Excavating and backfilling for utility trenches within the building footprint. 5. Removal of spoils from Rammed Aggregate Pier installation. 1.2 DEFINITIONS A. Backfill: Soil material used to fill an excavation. 1. Initial Backfill: Backfill placed beside and over pipe in a trench, including haunches to support sides of pipe. 2. Final Backfill: Backfill placed over initial backfill to fill a trench. B. Bedding Course: Aggregate layer placed over the excavated subgrade in a trench before laying pipe. C. Borrow Soil: Satisfactory soil imported from off-site for use as fill or backfill. D. Drainage Course: Aggregate layer supporting the slab-on-grade that also minimizes upward capillary flow of pore water. E. Excavation: Removal of material encountered above subgrade elevations and to lines and dimensions indicated. 1. Authorized Additional Excavation: Excavation below subgrade elevations or beyond indicated lines and dimensions as directed by Architect. Authorized additional excavation and replacement material will be paid for according to Contract provisions for changes in the Work. 2. Unauthorized Excavation: Excavation below subgrade elevations or beyond indicated lines and dimensions without direction by Architect. Unauthorized excavation, as well as remedial work directed by Architect, shall be without additional compensation. F. Fill: Soil materials used to raise existing grades. G. Structures: Buildings, footings, foundations, retaining walls, slabs, tanks, curbs, mechanical and electrical appurtenances, or other man-made stationary features constructed above or below the ground surface. H. Subgrade: Uppermost surface of an excavation or the top surface of a fill or backfill immediately below subbase, drainage fill, drainage course, or topsoil materials. 31 20 00 - 1 Midtown West 17070 Carmel, Indiana September 15, 2017 I. Utilities: On-site underground pipes, conduits, ducts, and cables, as well as underground services within buildings. I. Ground Improvement: Improvement of bearing capacity for footings and foundations by installation of Aggregate Pier System designed by others. 1.3 QUALITY ASSURANCE A. Preexcavation Conference: Conduct conference at Project site. 1.4 PROJECT CONDITIONS A. Utility Locator Service: Notify utility locator service for area where Project is located before beginning earth moving operations. PART 2 - PRODUCTS 2.1 SOIL MATERIALS A. General: Provide borrow soil materials when sufficient satisfactory soil materials are not available from excavations. B. Satisfactory Soils: Soil Classification Groups GW, GP, GM, SW, SP, and SM according to ASTM D 2487, or a combination of these groups; free of rock or gravel larger than 3 inches in any dimension, debris, waste, frozen materials, vegetation, and other deleterious matter. 1. Groups GC, SC, CL, and ML may be considered satisfactory soils when approved by the testing agency and maintained with 2 percent of optimum moisture content at time of compaction. C. Unsatisfactory Soils: Soil Classification Groups GC, SC, CL, ML, OL, CH, MH, OH, and PT according to ASTM D 2487, or a combination of these groups. 1. Unsatisfactory soils also include satisfactory soils not maintained within 2 percent of optimum moisture content at time of compaction. D. Engineered Fill: Naturally or artificially graded mixture of crushed stone, and natural or crushed sand; ASTM D 2940; with at least 90 percent passing a 1-1/2-inch sieve and not more than 12 percent passing a No. 200 sieve. E. Bedding Course: Naturally or artificially graded mixture of crushed stone, and natural or crushed sand; ASTM D 2940; except with 100 percent passing a 1-inch sieve and not more than 8 percent passing a No. 200 sieve. F. Drainage Course: Narrowly graded mixture of crushed stone; ASTM D 448; coarse-aggregate grading Size 57; with 100 percent passing a 1-1/2-inch sieve and 0 to 5 percent passing a No. 8 sieve. 31 20 00 - 2 Midtown West 17070 Carmel, Indiana September 15, 2017 PART 3 - EXECUTION 3.1 PREPARATION A. Protect structures, utilities, sidewalks, pavements, and other facilities from damage caused by settlement, lateral movement, undermining, washout, and other hazards created by earth moving operations. B. Protect and maintain erosion and sedimentation controls during earth moving operations. C. Protect subgrades and foundation soils from freezing temperatures and frost. Remove temporary protection before placing subsequent materials. 3.2 EXCAVATION, GENERAL A. Unclassified Excavation: Excavate to subgrade elevations regardless of the character of surface and subsurface conditions encountered. Unclassified excavated materials may include rock, soil materials, and obstructions. No changes in the Contract Sum or the Contract Time will be authorized for rock excavation or removal of obstructions. 1. If excavated materials intended for fill and backfill include unsatisfactory soil materials and rock, replace with satisfactory soil materials. 3.3 EXCAVATION FOR STRUCTURES A. Excavate to indicated elevations and dimensions within a tolerance of plus or minus 1 inch. If applicable, extend excavations a sufficient distance from structures for placing and removing concrete formwork, for installing services and other construction, and for inspections. 1. Excavations for Footings and Foundations: Footings are to bear on ground improved by the installation of Aggregate Pier System to be designed and installed by a specialty foundation contractor. Do not disturb bottom of excavation. Excavate by hand to final grade just before placing concrete reinforcement. Trim bottoms to required lines and grades to leave solid base to receive other work. 3.4 EXCAVATION FOR UTILITY TRENCHES A. Excavate trenches to indicated gradients, lines, depths, and elevations. B. Excavate trenches to uniform widths to provide the following clearance on each side of pipe or conduit. Excavate trench walls vertically from trench bottom to 12 inches higher than top of pipe or conduit unless otherwise indicated. 1. Clearance: 12 inches each side of pipe or conduit. C. Trench Bottoms: Excavate and shape trench bottoms to provide uniform bearing and support of pipes and conduit. Shape subgrade to provide continuous support for bells, joints, and barrels of pipes and for joints, fittings, and bodies of conduits. Remove projecting stones and sharp objects along trench subgrade. 31 20 00 - 3 Midtown West 17070 Carmel, Indiana September 15, 2017 1. Excavate trenches 6 inches deeper than elevation required in rock or other unyielding bearing material, 4 inches deeper elsewhere, to allow for bedding course. 3.5 SUBGRADE INSPECTION A. Proof-roll subgrade below the building slabs and pavements with a pneumatic-tired dump truck to identify soft pockets and areas of excess yielding. Do not proof-roll wet or saturated subgrades. B. Reconstruct subgrades damaged by freezing temperatures, frost, rain, accumulated water, or construction activities, as directed by the Geotechnical Testing Agency, without additional compensation. 3.6 UNAUTHORIZED EXCAVATION A. Fill unauthorized excavation under foundations or wall footings by extending bottom elevation of concrete foundation or footing to excavation bottom, without altering top elevation. Lean concrete fill, with 28-day compressive strength of 2000 psi, may be used when approved by Architect. 1. Fill unauthorized excavations under other construction, pipe, or conduit as directed by Architect. 3.7 STORAGE OF SOIL MATERIALS A. Stockpile borrow soil materials and excavated satisfactory soil materials without intermixing. Place, grade, and shape stockpiles to drain surface water. Cover to prevent windblown dust. 1. Stockpile soil materials away from edge of excavations. Do not store within drip line of remaining trees. 3.8 UTILITY TRENCH BACKFILL A. Place backfill on subgrades free of mud, frost, snow, or ice. B. Place and compact bedding course on trench bottoms and where indicated. Shape bedding course to provide continuous support for bells, joints, and barrels of pipes and for joints, fittings, and bodies of conduits. C. Trenches under Footings: Backfill trenches excavated under footings and within 18 inches of bottom of footings with satisfactory soil; fill with concrete to elevation of bottom of footings. Concrete is specified in "Cast-in-Place Concrete". D. Place and compact initial backfill of subbase material, free of particles larger than 1 inch in any dimension, to a height of 12 inches over the pipe or conduit. 1. Carefully compact initial backfill under pipe haunches and compact evenly up on both sides and along the full length of piping or conduit to avoid damage or displacement of piping or conduit. Coordinate backfilling with utilities testing. E. Place and compact final backfill of satisfactory soil to final subgrade elevation. 31 20 00 - 4 Midtown West 17070 Carmel, Indiana September 15, 2017 3.9 SOIL FILL A. Plow, scarify, bench, or break up sloped surfaces steeper than 1 vertical to 4 horizontal so fill material will bond with existing material. B. Place and compact fill material in layers to required elevations as follows: 1. Under steps and ramps, use engineered fill. 2. Under building slabs, use engineered fill. 3. Under footings and foundations, use engineered fill or lean concrete. 3.10 SOIL MOISTURE CONTROL A. Uniformly moisten or aerate subgrade and each subsequent fill or backfill soil layer before compaction to within 2 percent of optimum moisture content. 1. Do not place backfill or fill soil material on surfaces that are muddy, frozen, or contain frost or ice. 2. Remove and replace, or scarify and air dry, otherwise satisfactory soil material that exceeds optimum moisture content by 2 percent and is too wet to compact to specified dry unit weight. 3.11 COMPACTION OF SOIL BACKFILLS AND FILLS A. Place backfill and fill soil materials in layers not more than 8 inches in loose depth for material compacted by heavy compaction equipment, and not more than 4 inches in loose depth for material compacted by hand-operated tampers. B. Place backfill and fill soil materials evenly on all sides of structures to required elevations, and uniformly along the full length of each structure. C. Compact soil materials to not less than the following percentages of maximum dry unit weight according to ASTM D 1557: 1. Under footings and foundations, scarify and recompact top 12 inches of existing subgrade and each layer of backfill or fill soil material at 95 percent. 2. Under building slabs, scarify and recompact top 12 inches of existing subgrade and each layer of backfill or fill soil material at 93 percent. 3. Under walkways, and pavements scarify and recompact top 12 inches below subgrade and compact each layer of backfill or fill soil material at 93 percent. 4. For utility trenches, compact each layer of initial and final backfill soil material at 93 percent. 3.12 GRADING A. General: Uniformly grade areas to a smooth surface, free of irregular surface changes. Comply with compaction requirements and grade to cross sections, lines, and elevations indicated. B. Site Rough Grading: Slope grades to direct water away from buildings and to prevent ponding. Finish subgrades to required elevations within the following tolerances: 1. Walks: Plus or minus 1 inch. 31 20 00 - 5 Midtown West 17070 Carmel, Indiana September 15, 2017 C. Grading inside Building Lines: Finish subgrade to a tolerance of 1/2 inch when tested with a 10- foot straightedge. 3.13 DRAINAGE COURSE UNDER CONCRETE SLABS-ON-GRADE A. Place drainage course on subgrades free of mud, frost, snow, or ice. B. On prepared subgrade, place and compact drainage course under cast-in-place concrete slabs- on-grade as follows: 1. Place drainage course that exceeds 6 inches in compacted thickness in layers of equal thickness, with no compacted layer more than 6 inches thick or less than 3 inches thick. 2. Compact each layer of drainage course to required cross sections and thicknesses to not less than 98 percent of maximum dry unit weight according to ASTM D 698. 3.14 FIELD QUALITY CONTROL A. Testing Agency: Owner will engage a qualified geotechnical engineering testing agency to perform tests and inspections. B. Allow testing agency to inspect and test subgrades and each fill or backfill layer. Proceed with subsequent earth moving only after test results for previously completed work comply with requirements. C. Footing Subgrade: Footing Subgrade to be improved by installation of Rammed Aggregate Pier System. Coordinate with Specialty Foundation Contractor for monitoring, testing and inspection requirements. D. When testing agency reports that subgrades, fills, or backfills have not achieved degree of compaction specified, scarify and moisten or aerate, or remove and replace soil materials to depth required; recompact and retest until specified compaction is obtained. 3.15 PROTECTION A. Protecting Graded Areas: Protect newly graded areas from traffic, freezing, and erosion. Keep free of trash and debris. B. Repair and reestablish grades to specified tolerances where completed or partially completed surfaces become eroded, rutted, settled, or where they lose compaction due to subsequent construction operations or weather conditions. C. Where settling occurs before Project correction period elapses, remove finished surfacing, backfill with additional soil material, compact, and reconstruct surfacing. 1. Restore appearance, quality, and condition of finished surfacing to match adjacent work, and eliminate evidence of restoration to greatest extent possible. 3.16 DISPOSAL OF SURPLUS AND WASTE MATERIALS 31 20 00 - 6 Midtown West 17070 Carmel, Indiana September 15, 2017 A. Remove surplus satisfactory soil and waste materials, including unsatisfactory soil, trash, and debris, and legally dispose of them off Owner's property. END OF SECTION 31 20 00 31 20 00 - 7