6-5 P a y I t e m P a y U n i t
601.21 Gabions, Galvanized C u b i c Y a r d
601.211 Gabions, Galvanized and Hand Filled Cubic Yard 601.22 Gabions, PVC Coated C u b i c Y a r d 601.221 Gabions, PVC Coated and Hand Filled Cubic Yard 601.23 Mattresses, Galvanized: ________ C u b i c Y a r d
601.24 Mattresses, PVC Coated: _______ C u b i c Y a r d
SECTION 602 - PIPE LINING Reserved SECTION 603 - PIPE CULVERTS AND STORM DRAINS
603.01 Description This work shall consist of constructing or reconstructing pipe
culverts and storm drains, in accordance with these specificati ons, the Standard Detail plans and in reasonably close conformity with the lines and grades sh own on the plans or established. The word "pipe" in these specifications shall include both rou nd pipe and pipe arches.
603.02 Materials Meet Sections:
J o i n t M o r t a r 705.02 F l e x i b l e G a s k e t s 705.03 F l e x i b l e C u l v e r t P o l y v i n y l c h l o r i d e ( P V C ) P i p e 706.08 Polypropylene Pipe 706.10 Corrugated Steel, Metallic Coated Pipe 707.02 Corrugated Aluminum Alloy Pipe & Pipe Arches 707.06 Polymer Precoated, Galvanized Corrugated Steel 707.07 Pipe & Pipe Arches Aluminum Coated (Type 2) Corrugated Steel Pipe 707.10 Zinc-Coated (Galvanized) Corrugated Steel Pipe 707.11 Rigid Culvert R e i n f o r c e d C o n c r e t e P i p e 706.02 C o r r u g a t e d P o l y e t h y l e n e P i p e 706.06 6-6 Flexible culverts with a diameter of 48 inches or more shall ha ve the ends cut to a partial bevel as called for on the plans. The cut ends of galvanized s teel pipe shall be regalvanized or painted with a zinc aluminum paint conforming to Federal Spe cification TT-P-1561A or an approved equal. Helical corrugated pipe shall be re-rolled to form angular cor rugations on the ends. The corrugated bands for connecting pipe with 2 2/3 inches by ½ inch corrugations shall be not less than 10½ inches wide. Rigid culverts, designated to have the ends shaped to a partia l bevel, shall be either cast or cut to the required shape and dimensions. In either ca se, the edges of the pipe shall be even and true with no exposed reinforcing. Reinforced Concrete Pipe (RCP) with inside diameters of 10 ft. (120in) or greater shall be designed, fabricated and accepted in accordance with Section 534- Precast Structural Concrete. All Pipes or Culverts with ins ide diameters of 10 ft. (120in) o r greater shall be designed using the current version of the AASHTO LRFD Bridge Design Spec ifications with Maine Modified HL-93 for Strength 1.
603.03 Construction Requirements
603.031 General Culvert pipe and pipe arches shall be furnish ed under the following options unless otherwise specified. Option I The Contractor shall furnish any of the following ty pe of pipe under Option I: Corrugated Steel, Metallic (zinc or aluminum) Coated Pipe Reinforced Concrete Pipe Corrugated Polyethylene Pipe Any of the metal pipes allowed under Option III. Option III The Contractor shall furnish any of the following types of pipe under Option III. (Corrugated pipe used under this option shall be ad equate to equal the flow capacity of comparable smoothlined pipe): Corrugated Aluminum Alloy Pipe Polyvinylchloride (PVC) Pipe Polymer-Precoated Galvanized Corrugated Steel Pipe Reinforced Concrete Pipe Corrugated Polyethylene Pipe 6-7 Polypropylene Pipe Within any single run of culve rt pipe, including extensions of existing culverts, the type of pipe shall be the same unless otherwise specified or as directed by the Resident. In a closed drainage system, a run of culvert pipe shall be consider ed from catch basin to catch basin. In an open drainage system, a run of culvert shall be c onsidered from inlet to outlet. Option III polyvinylchloride ( PVC) pipe shall only be used in closed drainage systems, between catch basins. 603.0311 Corrugated Polyethylene and Polypropylene Pipe for Op tion III If inspection by the Resident reveals an unsatisfactory installati on, the Resident may direct the contractor to test installed Smooth Lined Corrugated Polyethyle ne and Polypropylene Pipe for Option III to ensure the vertical deflection does not excee d the maximum allowable deflection. Maximum allowable deflection shall be 5 percent of the sum of the nominal inside diameter minus a 1.5 percent undersize tolerance. Deflection tests shall not be performed until at least 30 days after completion of installation and compaction of backfill. The pipe shall be cle aned and inspected for offsets and obstructions before testing. For all pipes 24 inches and smaller, a mandrel shall be pulled through the pipe by hand to ensure the maximum allowable deflections have not been excee ded. The mandrel shall be certified by the Department prior to use. If the mandrel fails to pass through the pipe, the pipe will be deemed overdeflected. For pipes greater than 24 inches, deflections shall be determin ed by a method submitted and approved by the Department. If a mandrel is selected, the minimum diameter and length and other requirements shall conform to the dimensions and requ irements stated below. If other methods are used the measurements shall meet the minimum mandrel diameter requirements. Any overdeflected pipe shall be uncovered and if not damaged as determined by the Department shall be allowed for reinstallation. Damaged pipe s hall not be reinstalled and shall be removed from the work site. The mandrel shall be a rigid non-adjustable, odd numbered-leg ( 9 legs minimum) mandrel having an effective length not less than its nominal di ameter and having a minimum diameter at any point along the full length as follows: Nominal Size inches Minimum Mandrel Diameter inches 6-8 12 11.23 15 14.04 18 16.84 24 22.46 30 28.07 36 33.69 42 39.30 48 44.92 60 56.15 When deflection testing reveals over deflected pipe, all costs incurred by the Contractor including mandrel and deflection testing, reinstalla tion of pipe and delays shall be the responsibility of the Contractor. When deflection testi ng reveals satisfactory pipe, all costs for deflection testing will be paid for by the Department . 603.032 Excavation Trenches shall be excavated in accordance with the requirements of Section 206 - Structural Excavation and wide en ough to allow joining the culvert and compacting the bedding and backfill material under and around the culvert. Unless otherwise designated, trench walls shall be as nearly ve rtical as possible and the trench width no greater than necessary for installation of the culvert.
603.04 Bedding Culverts, less than 42 inches in diameter, sha ll be bedded on a firm
foundation of uniform density. Aft er placing the culvert pipe, backfill material shall be placed along the bottom of the trench, thoroughly tamped agains t the lower portion of the pipe with special care taken not to move the bedded pipe. For culverts 42 inches in diameter and larger, the bottom of t he trench shall be compacted to uniform density and shaped to fit a template with reasonable closeness for at least 10 percent of the culvert's total height. On all bedding, when bell and spigot pipe is used, the portion of trench at the joints shall be shaped to fit the bell.
603.05 Laying Culvert The Contr actor shall not install nor ba ckfill culverts between
December 15th and April 1st without written permission. Installing shall begin at the downstream end of the culvert line. Bell or groove ends of rig id culverts shall be placed facing upstream. Elliptically shaped culverts shall be placed with the major ax is within 5 degrees of vertical. Elliptically reinforced concrete pipe shall be placed with the vertical axis, indicated by the manufacturer, within 5 degrees of vertical.
603.06 Joining Culverts The met hod of joining rigid culvert s ections shall be such
that the ends are fully entered and the inner surfaces are reas onably flush and even. Joints 6-9 shall be made with Portland cement mortar, Portland cement grou t, rubber ring gaskets, or flexible plastic gaskets. The pipe ends shall be thoroughly c leaned before the joint is made. Mortared joints shall be made with an excess of mortar to form a bead around th e outside of the culvert and finished smooth inside. For gr outed joints, molds or runners s hall be used to retain the poured grout. Joints with rubber ring gasket or flexible plastic gasket shal l be made in accordance with the manufacturer's recommended procedures. When Portland cement mixtures are used, the completed joints s hall be covered to protect against drying. Flexible culvert section and metal end sections shall be firml y jointed by coupling bands. These bands shall meet the same applicable requirements as the flexible culvert being joined.
603.07 Shop Strutting All flexible circular culvert pipe 48 i nches in diameter and
larger shall be elongated along the vertical diameter in accord ance with one of the following two methods:
603.08 Backfilling Culverts and Storm Drains After the pipe i s installed, it will be
inspected before any backfill material is placed. All pipe fou nd to be out of alignment, unduly settled or damaged to the extent that full performance i s impaired, shall be taken up and re-laid or replaced. Trenches shall be backfilled in accordance with Section 206.03 and as follows. The backfill material shall be thoroughly rammed under the haunches of the pipe with power or pneumatic operated hand tampers. The remainder of the backfill shall be thoroughly compacted with power tampers or vibratory compactors or other a pproved equipment or combination of equipment. When the top of the pipe is e xposed above the top of the trenc h, the embankment material around the pipe shall be placed and compacted on each side of the pipe in the aforementioned manner described for backfilling trenches, for a width of 5 feet measured from the outside diameter of t he pipe. Only that portion of th e embankment on each side and top of the pipe, for a minimum distance of 15 inches measur ed from the outside diameter of the pipe, must be of material conforming to the req uirements described for backfilling in Section 206.03. Backfill material beyond these limits may contain stones larger than 3 inches but no greater than the thickness of the l ayer being placed. The embankment construction around the pipe shall continue up to an elevation 15 inches above the top of the pipe. Beyond these limits, the embankment shall be placed and compacted in accordance with the embankment construction requirements specif ied for the work except where the induced trench method is called for on the plans. When construction equipment is used or traffic is maintained t he Contractor shall provide a minimum cover of 3 feet over all pipes, if possible. Whenever this cover extends above the subgrade the Contractor shall temporarily place earth , which shall be removed when necessary to complete the work in accordance with the plan s, or as directed. Any deviation from this practice shall have prior approval.
603.09 Induced Trench Under this method, for designated rigid pipes only, the
embankment shall be completed as specified above, to a height a bove the culvert equal to the vertical outside diameter of the pipe plus 1 foot. A trenc h, equal in width to the outside horizontal diameter of the pipe, shall then be excavated to wit hin 1 foot of the top of the pipe. Trench walls shall be as nearly vertical as possible. H ay bales shall be used to fill the lower 1/4 to 1/3 of the trench. C onstruction of the embankment above shall then proceed in a normal manner. The trench shall be loosely filled with highl y compressible soil.
603.10 Removing and Relaying Culverts The pipe shall be caref ully removed from
its existing location, transported to and installed in the new location in accordance with these specifications for the pa rticular type of pipe involved. Pipe damaged by the Contractor shall be replaced with pipe of similar type by the C ontractor without additional compensation. 6-11 New metal bands or joint material shall be supplied and instal led when necessary.
603.11 Method of Measurement Culvert and storm drain pipe of the different types
and sizes, both new and re-laid, will be measured by the length in linear feet along the invert, laid as directed, complete in place, and accepted. Pip e laid in excess of the authorized length will not be included. When the ends of a pipe are s loped or skewed, the amount to be included for payment shall be the length along the invert of the pipe. When elbows, tees, wyes, or other special fittings are require d, each fitting shall be included for payment as 3 additional linear feet of the largest pipeline involved. Inlet grate units will be measured by each unit installed, com plete in place, and accepted. Concrete pipe ties shall be measured per Group (2 ties per Grou p).
603.12 Basis of Payment The accepted quantities of pipe for cu lverts and storm drains
will be paid for at the contract unit price per linear foot, fo r the types and sizes specified, complete in place. No payment will be made for pipe ordered without written approv al of the Resident when such pipe is not required to be installed for completion o f the work. Excavation for culverts and storm drains, including excavation below the pipe, for induced trench and for bedding and backfilling will be consider ed incidental, except as provided in Section 206 - Structural Excavation. Whenever minimum cover material extends above the subgrade, re moval of the cover material necessary to complete the work will not be paid for directly but shall be considered part of the work specified herein. Coupling bands and joint material will not be paid for separat ely but shall be considered included in the unit bid price for the type of pipe being used or re-laid. Existing culverts to be re-laid, salvaged, or wasted shall be removed and disposed of as directed. The excavation for removal of these culverts that is not paid for under other items or incidental to other items shall be paid for as Common Excavation. Inlet grate units will be paid for at the contract unit price each for the size specified, complete in place. The accepted quantity of concrete pipe ties will be paid for a t the contract unit price per Group. Such payment will be full compensation for furnishin g, installing, and all other 6-12 necessary incidentals for satisfactory completion of the work. Any grout or mortar necessary to repair chipping shall be incidental to the install ation of the pipe ties. Payment will be made under: Pay Item Pay Unit
603.15 12 inch Culvert Pipe Option I L i n e a r F o o t
603.16 15 inch Culvert Pipe Option I L i n e a r F o o t
603.17 18 inch Culvert Pipe Option I L i n e a r F o o t
603.18 21 inch Culvert Pipe Option I L i n e a r F o o t
603.19 24 inch Culvert Pipe Option I L i n e a r F o o t
603.20 30 inch Culvert Pipe Option I L i n e a r F o o t
603.21 36 inch Culvert Pipe Option I L i n e a r F o o t
603.159 12 inch Culvert Pipe Option III L i n e a r F o o t 603.169 15 inch Culvert Pipe Option III L i n e a r F o o t 603.179 18 inch Culvert Pipe Option III L i n e a r F o o t 603.189 21 inch Culvert Pipe Option III L i n e a r F o o t 603.199 24 inch Culvert Pipe Option III L i n e a r F o o t 603.2009 27 inch Culvert Pipe Option III L i n e a r F o o t 603.209 30 inch Culvert Pipe Option III L i n e a r F o o t 603.2019 33 inch Culvert Pipe Option III L i n e a r F o o t 603.219 36 inch Culvert Pipe Option III L i n e a r F o o t 603.229 42 inch Culvert Pipe Option III L i n e a r F o o t 603.239 48 inch Culvert Pipe Option III L i n e a r F o o t 603.249 54 inch Culvert Pipe Option III L i n e a r F o o t 603.259 60 inch Culvert Pipe Option III L i n e a r F o o t 603.269 66 inch Culvert Pipe Option III L i n e a r F o o t 603.279 72 inch Culvert Pipe Option III L i n e a r F o o t 603.289 84 inch Culvert Pipe Option III L i n e a r F o o t