and grades shown on the plans or established by the Engineer. This work shall include the furnishing and construction of such joints and connections to pipes, catch basins, headwalls, etc., as may be required to complete the structure as shown on the plans. Materials 617.02 Materials shall conform to the requirements of the following subsections: Structural plates and bolts Zinc dust-zinc oxide paint 707.09 708.03 Construction Requirements 617.03 Excavation, Bedding, and Backfill. Excavating, bedding, and backfilling shall be performed as prescribed in sections 206 and 603 supplemented as follows: When filling around and over arches before headwalls are in place, the first fill material shall be placed midway between the ends of the arch, forming as narrow a ramp as possible, until the top of the arch is reached. The ramp shall be built evenly from both sides and the fill material shall be compacted as it is placed. After the two ramps have been built to the top of the arch, the remainder of the fill material shall be deposited from the top of the arch both ways from the center to the ends, and as evenly as possible on both sides of the arch. If the headwalls are built before any fill material is placed around and over the arch, the fill material shall first be placed adjacent to one headwall until the top of the arch is reached, after which it shall be dumped from the top of the arch toward the other headwall, with care being taken to deposit the material evenly on both sides of the arch. In multiple installations the procedure above specified shall be followed, but extreme care shall be used to bring the material up evenly on each side of each arch so that unequal pressure will be avoided. 617.04 Fabrication: (a) Description of plates.-Plates shall consist of structural units of galvanized corrugated steel, or of corrugated aluminum alloy, as shown in the bid scheduled. Single plates shall be furnished in standard sizes to permit structure length increments of 2 feet. The gages of plates and the radius of curvature shall be as shown on the plans. Plates for a pipe-arch shall form a cross section made up of four circular arcs tangent to each other at their junctions and symmetrical about the vertical axis. The top shall be an arc of not more than 180 degrees nor less than 155 degrees. The bottom shall be an arc of not more than 50 degrees nor less than 10 degrees. The top shall be joined at each end to the bottom by an arc having a radius between 16 and 21 inches and of not more than 871⁄2 degrees nor less than 75 degrees. (b) Forming and punching plates.-Plates shall be formed to provide lap joints. The bolt holes shall be so punched that all plates having like dimensions, curvature, and the same number of bolts per foot of seam shall be interchangeable. Each plate shall be curved to the proper radius so that the cross-sectional dimensions of the finished structure will be as indicated on the plans. Bolt holes along those edges of the plates that will form longitudinal seams in the finished structure shall be staggered in rows 2 inches apart, with one row in the valley and one on the crest of the corrugation. Bolt holes along those edges of the plates that will form circumferential seams in the finished structure shall provide for a bolt spacing of not more than 12 inches. The minimum distance from center of hole to edge of plate shall be not less than 14 times the diameter of the bolt. The diameter of the bolt holes in the longitudinal seams shall not exceed the diameter of the bolt by more than 1% inch. Plates for forming skewed or sloped ends shall be cut to give the angle of skew or slope specified. Burned edges shall be free from oxide and burrs, and shall present a workmanlike finish. Legible identification numerals shall be placed on each plate to designate its proper position in the finished structure. 617.05 Footings for Arches. Footings for arches shall be constructed in accordance with the design shown on the plans and with the requirements prescribed in other sections for the several kinds of work involved. 617.06 Erection. 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. All plates shall be placed in the order recommended by the manufacturer with joints staggered so that not more than three plates come together at any one point. All bolts shall be drawn tight, without overstress, before beginning the backfill. After pipe or arches have been erected, all erection bolts and all spots where damage has occurred to spelter shall be given two coats of approved hot asphalt paint, or shall be wire brushed and given 2 coats of zinc dust-zinc oxide paint, as directed by the Engineer. 617.07 Strutting Structural-Plate Pipe. When shown on the plans, structural-plate pipe shall be strutted as provided in Subsection 603.07, with the exception that the vertical diameter of round pipe shall be increased 3 percent instead of 5 percent. Method of Measurement 617.08 Structural-plate pipe, pipe-arches, and arches will be measured in linear feet, installed in place, completed, and accepted. The number of linear feet will be the average of the top and bottom centerline lengths for pipe, the bottom centerline length for pipe-arches, and the average of the springing line lengths for arches. Basis of Payment 617.09 The quantities, determined as provided above, will be paid for at the contract price per unit of measurement, respectively, for each of the particular pay items listed below that is shown in the bid schedule, which prices and payment will be full compensation for the work prescribed in this section, except excavation and backfill which will be paid for as prescribed in Sections 206 and 603, and footings for arches which will be paid for as prescribed in the applicable section of this book. Payment will be made under: Pay item 617 (1) Structural-plate pipe, Pay unit When more than one material, size, or gage is specified for one pay item, letter suffixes will be included within the parentheses of the pay item number in order to differentiate between the different materials, sizes, or gages. Section 618.-CLEANING AND RECONDITIONING EXISTING DRAINAGE STRUCTURES Description 618.01 This work shall consist of cleaning and reconditioning existing pipe and appurtenant structures in reasonably close conformity with these specifications and as shown on the plans. Materials 618.02 Materials used for repair or replacement under the various pay items shall conform to the requirements of the applicable sections. Construction Requirements 618.03 Pipe Removed and Cleaned. The pipe shall be carefully removed and cleaned of foreign material, both within the barrel and at the jointed ends. 618.04 Pipe Cleaned in Place. All foreign material within the barrel shall be removed and disposed of by methods which do not damage the pipe. If approved by the Engineer, all or part of the pipe designated to be cleaned in place may be removed, cleaned, and relaid in accordance with the applicable sections. In such cases, the Contractor shall furnish all material required to replace damaged pipes and joints, perform all excavation and backfill, and re-lay the pipe, all at the contract bid price for this item. 618.05 Re-laying or Stockpiling Salvaged Pipe. Re-laying of pipe selected by the Engineer to be removed and cleaned shall be done where shown on the plans, in accordance with the appropriate section for the kind of pipe involved. The Contractor shall furnish all jointing material and shall replace pipe broken by him, in sufficient lengths to complete the designated length to be re-laid without added compensation. Salvaged pipe to be stockpiled shall be placed where shown on the plans and as directed by the Engineer. No pipe which has sustained structural damage shall be placed in stockpiles. The Contractor shall dispose of such damaged pipes at an approved location. 618.06 Reconditioning Drainage Structures. Structures such as manholes, inlets, and the like, designated on the plans or directed by the Engineer to be reconditioned shall have all debris removed, leaks repaired, missing or broken metalwork replaced, and each structure left in operating condition. Method of Measurement 618.07 Measurement will be made of the number of linear feet of pipe acceptably cleaned, removed, re-laid or stockpiled as designated in the bid schedule, irrespective of the kind or size involved. Pipe removed, cleaned, and re-laid will be measured in final position. Pipe removed, cleaned, and stockpiled will be measured by totaling the nominal laying lengths of all pipe units acceptably removed, cleaned, and placed in the stockpile. Pipe cleaned in place will be measured along the flow line of pipe line acceptably cleaned as directed. Measurement of drainage structures reconditioned will be made by actual count of the total number of units of each type acceptably completed. Basis of Payment 618.08 The quantities determined as provided above will be paid for at the contract price per unit of measurement respectively, for each of the pay items below that appear in the bid schedule, which price and payment will be full compensation for the work of this section except excavation and backfill paid for under section 206 in connection with re-laying salvaged pipe. Excavation and backfill necessary for pipe removal operations shall be done as part of the work of this section. The Contractor shall remove and replace without added compensation any pipe damaged by his operations and which cannot be acceptably repaired in place. If more than one type of drainage structure is described for an item in the bid schedule, letter suffixes will be added to the item number to differentiate between such structures. |