Drawings for the full trench width as actually cut. Site preparation, excavation, and backfill specification. The provisions set forth in this section shall be applicable to all underground wastewater and water piping installations, regardless of location, unless prior approval is received from the utilities engineer for special design considerations. American water works association, 1956 trenching machinery 9 pages. Site preparation, excavation, and backfill specification may 2014 process industry practices page 5 of 18. Backfilling is the process of putting the soil back into a trench or foundation once excavation, and the related work has been completed. Our trenchworks program allows you to estimate your trench excavation projects from your pipe profile drawings.
San antonio water system standard specifications for. Earthwork in excavation and backfilling of soil upto required depth is required for construction of foundation and trenches. Class ii, class iii, class iva, or class ivb as defined in. You may copy this method statement and submit to the engineer but please take a while to read your specification first as this may differ from it and revision will be needed. Excavation and backfill for utilities revised january 2020 31 23 331 section 31 23 33 excavation backfill and compaction for utilities part 1.
Rock excavation for trenches shall be according to opss 515. In addition, the method is also suitable for providing protection from. No extra payment will be made for the excavation or removal of rock to construct trenches unless rock excavation for trenches is listed as a pay item on the bid form. Tiein pointsinterferences encountered during project construction. This section includes grading, excavation trenching, dewatering and backfilling. Trench excavation shall consist of all earth excavation, within the limits specified herein, required to lay all pipes and appurtenances as shown on the plans or ordered by the engineer. The backfill process requires skills and heavy equipment as well as knowledge of the specifications, contract requirements, and soil conditions.
This section includes grading, excavation trenching, dewatering and backfilling for pipeline installation, roadways, walkways, and drives including all. Method statement for excavation and backfilling for underground services. Backfill under pavement of state highways backfill under all existing or proposed pavement under the jurisdiction of the. Normal depth of trench excavation shall be six inches 6 below the bottom of the pipe in earth.
Excavation classifications and backfill materials are specified in section 31 23 00, excavation and backfill, general. Unless otherwise shown or ordered, pipe shall be laid in an open trench. City of fargo specifications excavation, trenching, and backfilling for underground work part 1 description of work the terms excavation and trenching, either individually or collectively, as used in these specifications and other contract documents shall refer to and shall mean all material excavated or. Work covered in this section includes trench excavation for pipe, utility vaults and other utilities, pipe and utility vault bedding, and trench and utility vault backfill. Normal width of trench excavation in sheathed trenches up to 12. Prior to construction, the materials and method type shall be submitted and approved by the engineer. This work shall consist of all labor, equipment, and materials necessary for excavation, trenching, and backfilling for utility lines and other related work.
Use this category when estimating excavation, trenching, grading and other site preparation and earthwork that is done with heavy equipment. Excavation and backfilling of soil is a very important part of construction process, and care must be taken. Trenching of subsea pipelines is widely used as a means of stability enhancement in that the pipeline within a trench is partially shielded against hydrodynamic loads. Pdf method statement for excavation and backfilling for. Requirements for trenching and backfilling by customer for residential 120240 volt underground service lateral. Section 16 trenching and trench resurfacing 161 general excavation, backfilling and trench resurfacing shall be done in a manner such that both pedestrian and vehicular traffic are inconvenienced as little as possible.
All materials encountered during trench excavation, except rock and over excavation. Native backfill shall conform to the requirements for. The manitoba water services board section 022180 standard. Trench excavation and backfill section 2000 trench excavation and backfill trench excavation and backfill part 1 general 1. Native backfill is defined as granular soil excavated from a trench and it shall be free of ice, clay, debris and excessive organic matter. Backfilling techniques and materials in underground. The trench shall be backfilled with type 38 material to a height of 12 inches above the pipe in a maximum of 12 inch wetted lifts which shall be hand compacted. A trench is defined as a narrow underground excavation that is deeper than it is wide, and is no wider than 15 feet 4. The remaining trench shall be backfilled with type 38, type i, type ii or suitable existing backfill in a maximum of 12 inch wetted lifts, which shall be mechanically compacted.
Method statement for excavation and back filling works. Where the trench is within 100 of the top of slope cut or fill slope engineered compaction of backfill required in area cde 10. Trenchworks estimate your trench excavation and material. Before a trench is excavated, the designer should bear in mind that the trench support system and associated precautionary. Trenchworks estimates your trench excavation and material quantities.
The material placement in the pipe zone area shall first comply with table 1, when applicable. This section shall govern the excavation, trenching, and backfilling for water, sanitary sewer, and recycled water construction, unless otherwise noted in the contract documents. Read, highlight, and take notes, across web, tablet, and phone. Csa international 178 rexdale boulevard toronto, on m9w 1r3. American states utility services 31 20 00 1 excavation, trenching and backfilling revision date. Structural ramps used by employees designed by a competent person. The trench shall be excavated such that the pipe is always centered in the trench. To achieve uniform placement in the bedding material, shape the bedding or, if approved by. Place precast members, pipe, and concrete only on a dry, firm surface. Excavation and trenching are among the most hazardous construction operations. Alternatively, another structurally accepted design shall be provided by adjusting the limits of the excavation before backfilling. Native backfill soil shall not consist of expansive clay. The manitoba water services board section 022180 standard construction specifications pipe excavation, bedding 201 september 3 and backfill page 2 of 11 1.
Removal of bracing between sheeting shall only be done where backfilling proceeds and bracing is removed in a manner that does not relax trench support. Excavation of material to a level no greater than two feet below the bottom of the support system and only if the system is designed to support the loads. Every area of soil has unique characteristics, requiring. Trench excavation and backfill for underground utilities, sanitary sewer, storm sewer, water lines, and appurtenances shall conform to these specifications or as specified in the supplemental technical specifications or as authorized, in writing, by the engineer.
Where pavement is not replaced, the top 6 inches of backfill shall be of a select granular material from the excavation. Trenching, backfilling and compaction of utilities page 2. The excessive trench width may be due to unstable trench walls, inadequate or improperly placed bracing and sheeting which caused sloughing, accidental over excavation, intentional over excavation necessitated by the size of the contractors tamping and. Standard specifications and drawings chapter two trench excavation and backfill 22 material and gravel foundation for pipelines and pipeline structures, all at the developercontractors expense. It is the general intent of these specifications to specify conduct of the work in such manner as to cause the general public a minimum of inconvenience, with no exposure to unsafe conditions during construction, and to provide a trench that will. All incidental clearing, preliminary grading, structure. City of regina standard construction specification section. Section 19 trench excavation, bedding and backfill 19. Do not construct or place structures in the presence of water unless approved. The work to be performed in accordance with this section includes the excavation, trenching, backfilling, and surface repair for all pipelines, pipe culverts, box culverts, accessories and lines connected thereto.
The use of aggregate materials as described in this section as associated with either rigid or flexible designed pipe shall be as specified in this subsection below. The work included under this section consists of furnishing material and equipment, and performin g al l labor nec ess ary for excav ati ng, bac kf illing, filling and compa cti on of area s to be. Excavation and trenching procedures 4 p a g e 32018 policies, programs and procedures on any excavation where depth is expected to exceed four feet or where unstable soil is likely to be encountered, shoring or shielding equipment that will be used shall be on the site before any excavation. These costs are designed primarily for residential and light commercial earthwork estimating, excavation estimating and trenching estimates.
Borrow material must be approved by thecity engineer prior to use. The publications listed below form a part of this specification to the extent referenced. Do not use power excavating equipment within 24 inches of any existing buried cables or other electrical or communications equipment. Trenching, backfilling, and compacting of underground infrastructure.
Springville city standard specifications chapter 2 trench excavation and backfill 21 material and gravel foundation for pipelines and pipeline structures, all at the developercontractors expense. Highest compaction level is attainable at a specific. Your takeoffs can be performed either with a digitizer or with the keyboard. Guide to trench excavations shoring support and drainage. Guide to trench excavations shoring support and drainage measures guide to trench excavations shoring support and drainage measures download in pdf format. Trenching and excavation safety document revision date css12 1 june 2019 4. By noel mades posted on january 22, 2014 in method statement. Excavation and backfilling of soil work sequence and. Trenching and excavation safety 1 introduction excavation and trenching are among the most hazardous construction operations. North dakota department of transportation standard specification for. Where the pipe is to be set in a trench, it is necessary to have equipment with a large enough reach to allow proper rigging of the lifting straps, cables, etc.
Osha defines an excavation as any manmade cut, cavity, trench, or depression in the earths surface formed by earth removal. Section 3010 trench excavation and backfill 4 revised. Table 1 pipe zone maximum particle size for backfill. Trench excavation, backfill, and compaction shall include, but not necessarily be limited to, the excavation, backfill, and compaction of trenches for water mains. Accurately recorded asbuilt locations of projectinstalled underground utilities. Requirements for trenching and backfilling by developer. The proper sequence of excavation and backfilling is required to optimise the process and prevent safety issues. The work included under this section consists of excavating, backfilling and compaction as requi red for th e c ons tructi on of the pi ping sys tems as spec ifie d herei n. Either satisfactory excavated material or fill materials as. Excavation and backfill are to be planned and carried out so that the trench can be. Excavation and backfilling of soil work sequence and procedure.
Nominal pipe size inches maximum particle size inches 2 to 4 12 6 to 8 34 10 to 16 1 18 and larger 112 b. Aggregate layer placed between the subbase course and hotmix asphalt paving. Safe work method statement work in or near excavation deeper than 1. Section 19 trench excavation, bedding and backfill final 020907 city of elk grove standard construction specifications 192 underground facilities and the city has given final approval of the trench alignment. Safe work method statement work in or near excavation. If an item does not apply, please select the na option. During excavation, wet material increases the weight of the material, causes slippery and sticky conditions, thus reducing productivity during backfilling operations moisture content is a major factor for compaction.
Trenching and excavation safety occupational safety and. The following is a list of specifications which may be related to this. Perform all trench excavation and backfilling activities in accordance with the occupational safety and health act of 1970 pl 91596, as amended. The publications are referred to in the text by the basic designation only. Blasting blasting or the use of explosive devices will not be allowed. Jan 22, 2014 at the start of the project, in most projects i joined with, one of the activities shall be implemented or started first is excavation. Where the pipe is placed in a trench, if the trench walls are sloped dimensions are shown for backfill width or thickness. Backfill placed beside and over pipe in a trench, including haunches to support sides of pipe. City of regina standard construction specification section 02315 trench excavation and backfill latest revision. Dimensions backfill shall be placed full width of excavation except where slurry cement backfill may be substituted for backfill in the the class of rcp and installation type selected shall be the same. Backfill placed over initial backfill to fill a trench.
342 656 1467 809 635 781 1486 1561 309 1150 841 1031 893 193 594 474 61 142 1276 1330 538 804 1457 1371 1242 502 588 617 429 301 1143 764 118