SECTION 02215BP TRENCHING AND BACKFILLING

Transcription

1 SECTION 02215BP TRENCHING AND BACKFILLING

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3 Fluor-B&W Portsmouth, LLC (FBP) SITE PREPARATION INFRASTRUCTURE PHASE 1 SPECIFICATION COVER SHEET Client: U.S. Department of Energy Project: OSWDF SPECIFICATION SECTION: 02215BP TITLE: TRENCHING AND BACKFILLING SPECIFICATION PREPARED BY: (Specification Preparer, SP) Signature Name Date SCOPE AND FORMAT CHECKED BY: (Scope and Format Checker, SFC) Signature Name Date DETAILED REQUIREMENTS CHECKED BY: (Detailed Requirements Checker, DRC) Signature Name Date APPROVED BY: (Specification Approver, SA) Signature Name Date Record of Revision (Number and initial all revisions) Rev. No. Reason Date By Checked Approval A Initial July 2015 B Added sand cone note to 3.05F BP-i

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5 SECTION 02215BP TRENCHING AND BACKFILLING PART 1 GENERAL 1.01 SCOPE A. Work in this Section includes trenching and backfilling and placement of pipe and manhole embedment fill RELATED SECTIONS, PLANS, AND DOCUMENTS A. Section 02100BP - Surveying B. Section 02110BP - Clearing, Grubbing, and Stripping C. Section 02200BP - Earthwork D. Section 02270BP - Surface Water Management and Erosion Control E. Section 02721BP - Surface Water Control Structures and Pipes F. Section 02510BP - Raw Water Supply G. Contract Documents 1.03 REFERENCES A. Latest version of American Society for Testing and Materials (ASTM) Standards: 1. ASTM C136 Standard Test Method for Sieve Analysis of Fine and Coarse Aggregates 2. ASTM D2216 Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass 3. ASTM D2937 Standard Test Method for Density of Soil in Place by the Drive-Cylinder Method 4. ASTM D6938 Standard Test Method for In-Place Density and Water Content of Soil and Soil-Aggregate by Nuclear Methods (Shallow Depth) B. Construction and Material Specifications, 2013 Edition (Ohio C&MS), Ohio Department of Transportation (ODOT) SUBMITTALS A. For each source of pipe and manhole embedment fill materials, submit the following to the Construction Manager, at least 14 calendar days prior to use, for review and acceptance: 1. Source of the pipe and manhole embedment fill materials; 02215BP-1

6 2. Written certification from the Manufacturer or Supplier that materials conform to the requirements of this Section; 3. results of testing performed by the Manufacturer or Supplier that confirm that materials conform to the requirements of this Section; and 4. a 50 pound representative sample of the material from each source of manhole and pipe embedment fill material for visual examination and conformance testing. B. Submit to the Construction Manager, at least 14 calendar days prior to use, a catalogue cut sheet for marker tape. C. Submit to the Construction Manager, at least 14 calendar days prior to start of trenching activities, trench shoring and walkway design and details. Trench shoring and walkway design shall be certified by a Professional Engineer registered in the State of Ohio. D. Submit to the Construction Manager, at least 14 calendar days prior to commencement of Work described in this Section, a list of equipment and materials; description of construction means, methods, and techniques; and other required information for trenching and backfilling in the Contractor s Work Plan specified in Section 02200BP CONTRACTOR S QUALITY ASSURANCE A. Contractor s quality assurance requirements shall be in accordance with Attachment J-16 of the Contract Documents and this Section HEALTH AND SAFETY REQUIREMENTS A. Environmental Health & Safety/Training requirements shall be in accordance with Attachment J-13 of the Contract Documents. PART 2 PRODUCTS 2.01 MATERIALS A. Obtain backfill material from excavation and trenching included in this Contract. Additional material, if required, shall be obtained from the on-site stockpiles or on-site borrow areas identified by the Construction Manager. Controlled Low-Strength Material (CLSM) may be utilized as backfill in accordance with Section 02200BP Section 03100BP and Construction Manager approval. B. Furnish natural sand or sand manufactured from stone for pipe embedment fill material for reinforced concrete pipe (RCP), corrugated metal pipe (CMP), and high density polyethylene (HDPE) pipe and fittings described in Section 02721AR. The pipe embedment fill material shall conform to the requirements of Ohio C&MS Item for Type 2 Structural Backfill with the particle size requirements of Ohio C&MS Item A for fine aggregate. C. Furnish manhole embedment fill material for use as bedding for manholes, headwalls, drop inlets, and structures. Material shall conform to the requirements of Ohio C&MS Item with gradation requirements for No. 56 stone, as described in Ohio C&MS Table BP-2

7 D. Backfill material for RCP, CMP, and HDPE pipe shall conform to the fill material requirements for fill specified in Section 02200BP. E. Clay material for use in cutoff trenches shall be in accordance with Section 02200BP. F. Furnish minimum 4-inch wide metallic detectable marker tape with warning legend to mark underground pipes as shown on the Construction Drawings. G. Furnish trench shoring and walkway materials, where required, in accordance with the certified trench shoring and walkway design. H. Obtain construction water for moisture conditioning of backfill material from the Portsmouth D&D Site or at locations approved by the Construction Manager EQUIPMENT A. Furnish equipment to perform trenching and backfilling and pipe and manhole embedment fill material placement in accordance with this Section and the Contractor s Work Plan. PART 3 EXECUTION 3.01 GENERAL A. Verify existing conditions in accordance with Section 02100BP. B. Identify and stake existing above and belowground utilities in vicinity of trenching. Staking and/or marking shall be in accordance with Section 02100BP and as approved by the Construction Manager. C. Protect existing above and belowground utilities. D. In areas of trenching and backfilling, do not interrupt the existing utility service unless authorized by the Construction Manager. E. Do not damage or disturb permanent survey monuments, finished construction areas and structures, and existing utilities and structures. Damage shall be repaired or replaced to the original condition at the Contractor s expense. F. Perform grubbing and stripping in accordance with Section 02110BP, as necessary. G. Prior to performing Work described in this Section, install and maintain surface water management and erosion and sediment controls in accordance with Section 02270BP and the Contractor s Work Plan. H. Install construction safety fence in accordance with Section 02200BP. I. Stabilize disturbed areas in accordance with Section 02270BP BP-3

8 J. If a vertebrate paleontological or archaeological artifact discovery is made during trenching; stop work in the area of discovery and notification shall be made to the Construction Manager. Work in the area of discovery shall not resume until authorized by the Construction Manager. K. Implement dust control in accordance with the Contractor s Work Plan TRENCHING A. Trenches for installation of pipes, manholes, drop inlets, and other structures shall be to the depths, elevations, and dimensions shown on the Construction Drawings. Stockpile excess material from trenching at locations designated by the Construction Manager. Stockpile materials in accordance with Section 02200BP. B. Use shoring methods accepted by the Construction Manager. Shoring shall conform to applicable local, state, and federal requirements, including requirements of Attachment J-13, and shall be installed in accordance with the shoring and walkway design certified by the Ohioregistered Professional Engineer. Provide appropriate non-skid surface walkways for access across open trenches, such as constructed wooden walkways, conforming to the requirements of Attachment J-13 and installed in accordance with the design certified by the Ohio-registered Professional Engineer. Store shoring and walkway materials on-site prior to beginning trenching activities. Maintain the safety and stability of excavations and trenches by properly installing supports according to the certified design and the Manufacturer s requirements. C. Protect and maintain the trench bottom. Remove rock fragments or raveled materials that collect on the trench bottom. Backfill over-excavations with fill in accordance with Section 02200BP. Excavate unsuitable soil encountered at the trench bottom and backfill to trench bottom elevation with fill in accordance with Section 02200BP. D. Where trenches will be excavated in fill areas, perform trenching only after fill has reached at least 24 inches above the top of the pipe design elevation unless otherwise shown on the Construction Drawings. E. For pipe installation, limit the maximum length of open trench to 200 feet in advance and 200 feet behind pipe unless otherwise authorized by the Construction Manager. F. Continuously dewater trenches when water is present. Perform dewatering in accordance with Section 02200BP. G. Do not leave the bottom of trenches rough or uneven; smooth out the bottom of trenches to the required design grade BACKFILLING A. General 1. Do not backfill with frozen or saturated material. Note; CLSM can be placed year around provided it is protected from freezing until harden. 2. Do not backfill over frozen, wet, or soft trench bottom or side slopes. Remove materials that are frozen, wet, or soft as specified in this Section. 3. Do not disturb or damage piping or geosynthetics during backfilling; damaged materials shall be replaced at the Contractor s expense BP-4

9 4. Do not use compaction equipment that exerts greater than 10 pounds per square inch (psi) ground pressure over piping that is covered by less than 12 inches of backfill material. B. Placement of pipe embedment fill for pipes 1. Place pipe embedment fill in maximum 8-inch thick loose lifts and compact to the elevation of the bottom of the pipe. 2. Compact pipe embedment fill with a minimum of four passes with vibratory hand compaction equipment. 3. Grade the pipe embedment fill to the bottom of the pipe design elevation prior to placing pipe. 4. Place pipe on top of the compacted and graded pipe embedment fill. 5. Place pipe embedment fill in maximum 8-inch thick loose lifts to the spring line of the pipe as shown on the Construction Drawings. Compact each lift with a minimum of four passes with vibratory hand compaction equipment, or by other means, methods, and techniques described in the Contractor s Work Plan. C. Placement of manhole embedment fill for headwalls, manholes, drop inlets, and other structures. 1. Place manhole embedment fill in maximum 6-inch thick loose lift and compact to the design elevation of the bottom of the concrete headwalls, manholes, and inlets as shown on the Construction Drawings. 2. Compact manhole embedment fill with a minimum of four passes with vibratory hand compaction equipment, or by other means, methods, and techniques described in the Contractor s Work Plan. 3. Grade the manhole embedment fill to the bottom of design elevation prior to placing concrete headwalls, manholes, and inlets. 4. Place concrete headwalls, manholes, and inlets on top of the compacted and graded manhole embedment fill. 5. Place backfill for structures in accordance with this Section and as shown on the Construction Drawings. D. Placement of backfill material for pipes 1. After placement and compaction of pipe embedment fill to the limits shown on the Construction Drawings, place the first lift of backfill material in maximum 12-inch thick loose lift. Place subsequent lifts of backfill material in maximum 8-inch thick loose lifts. 2. Compact the backfill material in each lift to the specifications for fill material specified in Section 02200AR with a minimum of four passes of a walk-behind pad-foot compactor, hand tamper, or vibratory plate compactor, as appropriate. E. Placement of backfill for headwalls, manholes, drop inlets, and structures 1. Do not place backfill material around structures until concrete has reached a minimum of 70 percent of the required 28-day compressive strength. 2. Place the backfill material in maximum 8-inch thick loose lifts if the compaction equipment operating weight is greater than 2,000 pounds, and in maximum 4-inch thick loose lifts if the compaction equipment operating weight is less than 2,000 pounds. 3. Compact backfill for structures a minimum of 3 feet beyond the outer walls with a minimum of four passes using a walk-behind pad-foot compactor, hand tamper, or 02215BP-5

10 vibratory plate compactor, or by other means, methods, and techniques described in the Contractor s Work Plan. 4. Compact the backfill material in each lift to the specifications for fill material specified in Section 02200AR. F. Place marker tape in backfill below finished grade above underground pipes as shown on the Construction Drawings. Place marker tape to the depth shown on the Construction Drawings CONSTRUCTION QUALITY REQUIREMENTS A. CQC shall be performed in accordance with the Contract Documents. B. Contractor shall coordinate construction activities through the Construction Manager to accommodate the activities required of the CQC Consultant. C. Contractor shall notify the Construction Manager at least 7 calendar days prior to commencement of trenching and backfilling activities in new locations. D. CQC Consultant will monitor trenching and backfilling as specified in this Section. E. CQC Consultant will perform conformance testing on the pipe embedment fill, manhole embedment fill, and backfill materials to establish compliance with this Section and Section 02200BP, as applicable. Contractor shall provide equipment, such as shovels, hand augers, and backhoes, and labor to assist CQC Consultant in obtaining samples from borrow areas, trenching, and stockpiles. Conformance testing for backfill material shall be as required for fill specified in Section 02200BP. The conformance testing and minimum testing frequencies for pipe embedment fill and manhole embedment fill material shall be: 1. particle-size analysis (ASTM C136) at 1 test per 1,000 yd 3. F. CQC Consultant will perform performance testing on backfill to establish compliance with this Section and Section 02200BP, as applicable. The performance testing and minimum testing frequencies for backfill shall be: 1. nuclear density and moisture (ASTM D6938) at 1 test per 100 linear feet per lift. 2. drive cylinder (ASTM D2937) or sand cone (ASTM D1556) at 1 test per 25 nuclear density and moisture tests. 3. moisture content (ASTM D2216) at 1 test per 10 nuclear density and moisture tests. G. CQC Consultant and Construction Manager will review and verify as-built bottom of trench elevations prior to backfilling SURVEY CONTROL A. Survey the locations, limits, and grades of the compacted backfill in accordance with Section 02100BP. B. Survey the locations, limits, and grades of structures and pipes, including invert elevations, in accordance with Section 02100BP BP-6

11 3.06 TOLERANCES A. Trench bottom shall be within -0.3 to +0.1 feet of the depth indicated on the Construction Drawings. B. Top of pipe and manhole embedment fill material shall be placed within 0.0 to +0.2 feet of the depth indicated on the Construction Drawings. C. Backfill material shall be placed within 0.0 to +0.1 feet of the existing ground or finished grade indicated on the Construction Drawings. [END OF SECTION] 02215BP-7