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601A.20 Placing. Precast prestressed concrete piling shall be placed in accordance with the requirements for precast concrete piling in section 600A. Other precast prestressed structural members shall be placed in the structure in conformity with the plans and special provisions governing the particular type of structure to be built.

Method of Measurement

601A.21 Structural Members. The quantity to be measured for payment will be the actual number of precast prestressed concrete structural members, except piling, of the several types and sizes, installed in place, completed and accepted. Each member will include the concrete, reinforcement and prestressing steel, enclosures for prestressing steel, anchorages, plates, nuts, and other such material contained within or attached to the unit.

Piling will be measured as provided in section 600A.

Lump-sum measurement will be in accordance with subsection 109.01.

601A.22 Other Items. The quantities of other contract items which enter into the completed and accepted structure will be measured for payment in the manner prescribed for the several items involved.

Basis of Payment

601A.23 Structural Members. The quantity, determined as provided above, will be paid for at the contract price per unit of measurement or lump sum for the pay items listed below and shown in the bid schedule, which price and payment will be full compensation for the work prescribed in this section except prestressed concrete piling, which will be paid for as provided for in section 600A.

601A.24 Other Items. The quantities of other contract items which enter into the completed and accepted structure will be paid for at the contract unit prices for the several' pay items as prescribed for the items involved.

Payment will be made under:

Pay item

601A (1) Prestressed concrete structural

members (identification)

Pay unit

Each.

601A (2) Prestressed concrete

Lump sum.

When more than one type or size of structures are specified, letter suffixes will be included as part of the pay item number in order to differentiate between the various members.

Section 602.-REINFORCING STEEL

Description

602.01 This work shall consist of furnishing and placing reinforcing steel in accordance with these specifications and in reasonably close conformity with the plans.

Materials

602.02 Materials. Reinforcing steel shall meet the requirements of subsection 709.01.

Construction Requirements

602.03 Order Lists. Before ordering material, all order lists and bending diagrams shall be furnished by the Contractor for the approval of the Engineer, and no materials shall be ordered until such lists and bending diagrams have been approved. Approval of order lists and bending diagrams will in no way relieve the Contractor of his responsibility for ascertaining accuracy of such lists and diagrams. Revision of materials furnished in accordance with such lists and diagrams to meet compliance with design drawings shall be at the expense of the Contractor.

602.04 Protection of Materials. Reinforcing steel shall be protected at all times from damage and shall be stored on blocks to prevent mud caking. Prior to placing concrete, reinforcing steel which is to be embedded, shall be free from heavy rust, dirt, mud, loose scale, paint, oil, or any other foreign substance.

602.05 Bending. Unless otherwise permitted, all reinforcing bars requiring bending shall be bent cold and shall be bent in acordance with American Concrete Institute procedures unless otherwise detailed. Bars partially embedded in concrete shall not be bent except as shown on the plans or otherwise permitted. Qualified men shall be employed for cutting and bending, and proper appliances shall be provided for such work. Should the Engineer approve the application of heat for field bending reinforcing bars, precautions shall be taken to assure that the physical properties of the steel will not be materially altered.

602.06 Placing and Fastening. All reinforcing steel shall be accurately placed and during the placing of concrete, firmly held by approved supports in the position shown on the plans. Reinforcing bars shall be securely fastened together. Reinforcement placed in any member shall be inspected and approved before any concrete is placed.

Main reinforcement bars carrying determinate stresses shall be spliced only where shown on the plans or on approved shop drawings.

Method of Measurement

602.07 Reinforcing steel will be measured by the pound, based on the theoretical number of pounds or, whenever provided, on a lump sum basis and complete in place as shown on the plans or placed as ordered.

The quantities of materials furnished and placed will be based upon the calculated weights of the reinforcing steel actually placed in accordance with these specification. The weights calculated will be based upon the following table:

Bar size 1/4" #3 #4
Weight
per

L.F.

#5 #6 #7 #8 #9 #10 #11 #14 #18

in lbs. 0.167 0.376 0.668 1.043 1.502 2.044 2.670 3.400 4.303 5.313 7.650 13.600

If the bid schedule provides for a lump sum payment, no measurement for payment will be made.

No measurement or payment will be made for splices added by the Contractor for his convenience.

Whenever there are no bid schedule items provided for reinforcing steel, costs will be considered as incidental to other bid schedule items.

Basis of Payment

602.08 The accepted quantities of reinforcing steel, determined as provided above, will be paid for at the contract price per pound or lump sum price, complete in place. No allowance will be made for clips, wire or other material used for fastening reinforcement in place.

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603.01 This work shall consist of the construction or reconstruction of pipe culverts and storm drains, hereinafter

referred to as "conduit" in accordance with these specifications and in reasonably close conformity with the lines and grades shown on the plans or established by the Engineer.

Materials

603.02 Materials. Materials shall meet the requirements specified in the following subsections:

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Packing compound

705.09

705.10

705.11

Performed plastic sealing compound

Bedding material shall conform to the requirements of subsection 603.04.

Backfill materials shall conform to the requirements of subsection 603.08.

When the location of manufacturing plants allows, the plants will be inspected periodically for compliance with specified manufacturing methods, and material samples will be obtained for laoratory testing for compliance with materials quality requirements. This can be the basis for acceptance of manufacturing lots as to quality.

Prior to and during incorporation of materials in the work, these materials will be subject to the latest practicable inspections and checks by the Engineer.

Construction Requirements

603.03 Excavation. Trenches shall be excavated in accordance with the requirements of Section 206-Structure Ex

cavation, to a width sufficient to allow for proper jointing of the conduit and thorough compaction of the bedding and backfill material under and around the conduit. Where feasible, trench walls shall be vertical.

The completed trench bottom shall be firm for its full length and width. Where required, in the case of cross drains, the trench shall have a longitudinal camber of the magnitude specified.

When so specified on the plans, the excavation for conduits placed in embankment fill, shall be made after the embankment has been completed to the specified or directed height above the designed grade of the conduit.

603.04 Bedding. The conduit bedding shall conform to one of the classes specified. When no bedding class is specified the requirements for Class C bedding shall apply.

Class A bedding shall consist of a continuous concrete cradle conforming to the plan details.

Class B bedding shall consist of bedding the conduit to a depth of not less than 30 per cent of the vertical outside diameter of the conduit. The minimum thickness of bedding material beneath the pipe shall be 4 inches. The bedding material shall be sand or selected sandy soil all of which passes a %-inch sieve and not more than 10 per cent of which passes a No. 200 sieve. The layer of bedding material shall be shaped to fit the conduit for at least 15 per cent of its total height. Recesses in the trench bottom shall be shaped to accommodate the bell when bell and spigot type conduit is used.

Class C bedding shall consist of bedding the conduit to a depth of not less than 10 percent of its total height. The foundation surface, completed in accordance with subsection 206.03 (c) shall be shaped to fit the conduit and shall have recesses shaped to receive the bells, if any.

For flexible pipe the bed shall be roughly shaped and a bedding blanket of sand or fine granular material as specified above shall be provided as follows:

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For large diameter structural plate pipes the shaped bed need not exceed the width of bottom plate.

603.05 Laying Conduit. The conduit laying shall begin at the downstream end of the conduit line. The lower segment of the conduit shall be in contact with the shaped bedding throughout its full length. Bell or groove ends of rigid con

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