530ROADWAY PIPE CULVERTS

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backfill shall be brought up evenly in layers on both sides of the pipe for its full length until the trench is filled or up to subgrade elevation if the trench is in cut. When the plans require stone or aggregate backfill, the material will be compacted (in layers not exceeding 6 inches) to the satisfaction of the Engineer. Mechanical tampers or vibrator plate compactors shall be used unless another method of compaction is approved in writing. When the top of the pipe is exposed above the top of the trench, embankment material shall be placed and compacted for a width on each side of the pipe equal to at least twice the horizontal inside diameter of the pipe, or 12 feet {4 m} whichever is less. The embankment on each side of the pipe, for a distance equal to the horizontal inside diameter of the pipe, shall be of the same material and compacted in a normal manner. All pipe, after being bedded and backfilled as specified in this Section, should be protected by a 3 foot {0.6 m} cover of fill before heavy equipment is permitted to cross during construction of the roadway.

The Contractor shall exercise necessary care in installing and backfilling pipe, and it shall be his responsibility to see that the pipe is not damaged by lateral forces during backfilling, by heavy loads operating over the pipe, or by other causes. All damaged pipe shall be replaced or repaired by the Contractor at his own expense at the option of, and to the satisfaction of, the Engineer. Any pipe not true to designated alignment and grade within specified tolerances, or any pipe that shows settlement due to faulty installation, shall be relaid or replaced by the Contractor without additional compensation. Any pavement that settles or breaks over a pipe shall be replaced or repaired by the Contractor, at the option of the Engineer, without additional compensation. All pipe lines shall be thoroughly cleaned out prior to final acceptance.

For pipe sizes less than 42 inches {1050 mm} in diameter, the tunneling equipment used in the jacking (boring) operation shall have a steerable cutting head equipped with a grade indicator. For pipe sizes 42 inches {1050 mm} in diameter and greater, the tunneling equipment used in the jacking (boring) operation shall be a laser-guided tunnel boring machine (TBM). The use of unguided auger-type boring equipment will not be permitted. The tunneling equipment shall also be equipped with a closed-face cutting head or otherwise equipped to prevent unstable soils from entering the tunnel. The tolerance for grade control shall be plus or minus 0.020 feet per 100 feet {20 mm per 100 m} of length. The tolerance for line shall be 0.20 feet per 100 feet {200 mm per 100 m} of length. Smooth steel pipe shall be continuously welded at joints to form a rigid, watertight installation. Any coating disturbed during the welding procedure shall be repaired, both inside and outside, in a manner acceptable to the Engineer.

530.04Method of Measurement

The accepted length of pipe culverts laid as ordered will be measured along the bottom flowline, or invert, of the pipe complete in place. Measurements will be made between inside walls of designated structures (junction boxes, inlets, etc.) and along the centerline of the flowline of special fittings (elbows, wyes, etc.). The above applies to round or arch, beveled or unbeveled, pipe. However, in no case will measurement be made for lengths greater than the sum of the nominal laying lengths of the pipe sections used or for lengths greater than the length of culvert ordered by the Engineer. No separate measurement for payment will be made for the excavation and/or backfill volume needed to reroute water for temporary drainage which might be necessary for the proper installation of the pipe or to perform the imperfect trench method of installation. Structure excavation and foundation backfill, including that necessary for the installation of roadway pipe of a temporary nature, when ordered will be measured and paid for as prescribed in Section 214. The accepted length of pipe culverts jacked (bored) as ordered and acceptably installed will be measured along the bottom flowline, or invert, of the pipe complete in place. The limits of measurement of jacked (bored) pipe under this Section will not exceed the length along the flowline of the pipe from face to face of the boring pit or the length shown on the plans, except as otherwise directed in writing by the Engineer, whichever is less. There will be no separate measurement for payment for structure excavation and foundation backfill for pipe installed by the jacking (boring) method. CORRUGATED METAL STRUCTURAL PLATE PIPE, ARCH PIPE, AND ARCH CULVERTS 409

530.05Basis of Payment

The accepted length of pipe culverts, measured as above provided, will be paid for at the respective contract unit prices for the various sizes, and types of pipe provided in the proposal, complete in place, which shall be payment as herein provided and also for all work, equipment, materials, and incidentals connected with the execution of the Class Bedding specified for installation, except that Foundation Backfill and Structure Excavation shall be paid for separately.

The internal diameter of circular pipe, the span and rise of arch pipe, the class of pipe, the class of pipe bedding, if other than Class "C", and the type or types of pipe allowed will be shown in the item name. The internal diameter of jacked (bored) pipe and the type or types of pipe allowed will be shown in the item name.

530-A ___ inch {mm} Roadway Pipe, Class * Bedding ( ** ) - per linear foot {meter} 530-B ___ inch {mm} Span, ___ inch {mm} Rise Roadway Pipe, Class * Bedding ( ** ) - per linear foot {meter} 530-C _____ inch {mm} Roadway Pipe, Jacked Installation ( *** ) - per linear foot {meter} * If other than Class "C", so note. ** Show acceptable types of pipe. *** Specify "Smooth Steel", "Class __ R.C.", etc. if applicable. Examples: Specific Type: Class ____ R.C., or ____ gage {mm} C.C.S.P.I., or ____ gage {mm} C.C.S., or ____ gage {mm} C.C.A.P.I., or____ gage {mm} C.C.A. Optional Types: Class ____ R.C. or equal strength C.C.M.P.I. or Class ____ R.C. or equal strength C.C.M. CORRUGATED METAL STRUCTURAL PLATE PIPE, ARCH PIPE, AND ARCH CULVERTS

531.01Description

This Section shall cover the work of furnishing corrugated metal structural plate pipe, arch pipes, and arches (coated and uncoated) of the sizes, plate thickness, and dimensions required by the plans and installing such at the locations shown by the plans or designated, all in conformity with these specifications to the lines and grades given. The corrugated metal plate pipe shall be full circle or other approved pipe shapes. Corrugated metal plate arches shall be part of circle construction anchored on footings, floor, or grillage of description shown on the plans.

531.02Materials

All materials shall conform to the provisions of Division 800, Materials. Specific reference is made to Section 841, Corrugated Metal Structural Plate for Pipe and Arches.

531.03Construction Requirements

The pipe or arch structure shall be carefully erected according to plans and erection drawings and true lines and grades, as given, on approved foundations. Arches shall be set in galvanized steel shapes on concrete or masonry footings, or on timber grillages or concrete floors built in full compliance with the specifications for Sections 501, 509, or 611. The structure shall be erected on its permanent foundations.

Structural plate pipe, pipe arches, and arches shall be erected in their final position by connecting the plates with bolts at longitudinal and circumferential seams. Drift pins may be used to facilitate matching of holes. Each plate shall have legible identification numerals to designate its position in the