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613.15 Plank Floors. Plank shall be of the grade specified and shall be surfaced four sides (S4S).

Single plank floors shall consist of a single thickness of planks supported on stringers. The planks shall be laid heart side down, with one-fourth-inch openings between them for seasoned material and with tight joints for unseasoned material. Each plank shall be securely spiked to each stringer. The planks shall be carefully graded as to thickness and so laid that no two adjacent planks shall vary in thickness by more than one-sixteenth of an inch.

Two-ply timber floors shall consist of two layers of flooring supported on stringers. The lower course shall be pressuretreated with creosote oil. The top course may be laid either diagonal or parallel to the centerline of roadway, as specified, and each floor piece shall be securely fastened to the lower course. Joints shall be staggered at least 3 feet. If the top flooring is placed parallel to the centerline of the roadway, special care shall be taken to securely fasten the ends of the flooring. At each end of the bridge these members shall be beveled.

613.16 Laminated or Strip Floors. Pieces for laminated or strip floors shall have a nominal thickness of 2 inches and shall be surfaced one edge hit or miss 18-inch scant (SIE-H or M 48-inch scant), and when so specified, shall be surfaced one side hit or miss 18-inch scant (SIS-H or M 18-inch scant).

The pieces shall be of the grade specified. They shall be placed on edge, at right angles to the centerline of roadway. Each piece shall be spiked to the preceding piece at each end and at approximately 18-inch intervals, with the spikes driven alternately near the top and bottom edges. The spikes shall be of sufficient length to pass through two pieces and at least halfway through the third piece.

If timber stringers are used, every other piece shall be toenailed to every other stringer. The size of the spikes shall be as shown on the plans. When specified on the plans, the piece shall be securely attached to steel stringers by the use of approved galvanized metal clips. Care shall be taken to have each piece vertical and tight against the preceding one, and bearing evenly on all the stringers.

Pieces shall be of sufficient length to bear on at least four stringers. No splicing of pieces between stringers will be allowed. End joints on any one stringer shall be no closer than every third piece. End joints in adjoining pieces shall be no closer than every second stringer.

613.17 Wheel Guards and Railings. Wheel guards and railings shall be accurately framed in accordance with the plans and erected true to line and grade.

Unless otherwise specified, wheel guards, rails, and posts shall be surfaced on four sides (S4S).

Wheel guards shall be laid in sections not less than 12 feet long. All rails shall be squarely butt-joined at the posts and the rails shall break joints.

613.18 Trusses. Trusses, when completed, shall show no irregularities of line. Chords shall be straight and true from end to end in horizontal projection and, in vertical projection, shall show a smooth curve through panel points conforming to the correct camber. All bearing surfaces and joints shall fit accurately. Uneven or rough cuts at the points of bearing will be cause for rejection of the piece containing the defect.

613.19 Drains. Drains shall be provided where indicated on the plans. They shall be constructed with galvanized iron linings and shall be arranged to discharge free of the structure.

613.20 Painting. Rails and rail posts shall be painted with three coats of white paint unless otherwise specified on the plans. Other parts of the structure shall be painted when so designated on the plans.

613.21 Cleaning Up. Upon completion and before final acceptance, the Contractor shall remove all falsework, falsework piling down to at least 2 feet below the finished ground line, excavated or unused materials, rubbish, and temporary buildings. He shall replace or renew any fences damaged and repair in an acceptable manner all property, both public and private, which may have been damaged during the prosecution of the work, and shall leave the work site and adjacent highway in a neat and presentable condition satisfactory to the Engineer. All excavated material or falsework placed in the stream channel during construction shall be removed by the Contractor before final acceptance.

Method of Measurement

613.22 The quantities to be paid for will be the number of thousand feet board measure (MFBM) of each species of lumber and timber, complete in place and accepted. Measurements of lumber and timber will be computed from the nominal dimensions and actual lengths. The cross-sectional dimensions on the plans will be interpreted as standard sizes. The standard cross-sectional dimensions will be used in the computations even though the actual size be scant in the dimension specified. The measurement of lumber and timber will include only such material as is a part of the completed and accepted work, and will not include timber used for erection purposes, such as falsework, bracing, sheeting, etc.

No portion of any pile will be included in the measurement for payment.

Basis of Payment

613.23 The quantities, determined as provided above, will be paid for at the contract price per unit of measurement, respectively, for each particular pay item 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 piling, which will be paid for as provided in section 600A, and except bridge railing when the bid schedule contains an estimated quantity for timber bridge railing under section 612.

Payment will be made under: Pay item

Pay unit 613(1) Untreated timber

MFBM 613(2) Treated timber,



When more than one kind of preservative is specified for treated timber, letter suffixes will be inserted within the parentheses as a part of the item numbers in order to differentiate between the various preservatives.

Section 614.—DAMP-PROOFING

Description 614.01 This item shall consist of damp-proofing concrete or masonry surfaces with tar or asphalt, as called for, in reasonably close conformity with these specifications and at the locations shown on the plans or ordered by the Engineer.


614.02 Materials shall conform to the requirements specified in the following subsections: Primer

702.06(a) or (b) as applicable Tar

702.06(c) Asphalt


Construction Requirements 614.03 After the concrete is cured in conformity with the requirements given in section 601, the surfaces to be dampproofed shall be allowed to dry at least 10 days. They shall then be coated thoroughly with four coats of primer applied cold with a brush or spray gun and each coat shall be absorbed before the succeeding one is applied. After absorption of the fourth coat, a seal coat shall be heated if necessary and applied at a temperature compatible with the type of material and brushed or sprayed thoroughly into all surfaces. The seal coat shall have hardened before any water or earth is allowed to come against it. No coat shall be applied when the concrete or the preceding coat is damp, or at any time when the weather is unsuitable.

Method of Measurement 614.04 The quantity to be paid for will be the actual number of square yards of surface damp-proofed, completed, and accepted. If a lump-sum payment is to be made, measurement will be in accordance with subsection 109.01.

Basis of Payment 614.05 The quantity, determined as provided above, will be paid for at the contract price per unit of measurement for the pay item listed below that is shown in the bid schedule, which price and payment will be full compensation for the work prescribed in this section.

Payment will be made under: Pay item

Pay unit 614(1) Damp-proofing

Square yard. 614(2) Damp-proofing

Lump sum.


Description 615.01 This item shall consist of the waterproofing of concrete surfaces in reasonably close conformity with these specifications, by the method designated in the bid schedule, and at the locations shown on the plans or ordered by the Engineer.

Materials 615.02 Materials shall conform to the requirements specified in the following subsections: Primer for asphalt

702.06(a) Primer for tar

702.06(b) Tar for mop coat

702.06 (c) Asphalt for mop coat

702.06(d) Waterproofing fabric

702.06(e) Mortar

702.06 (f) Asphalt plank

702.06 (g) Asphalt roll roofing

702.06 (h) Oakum

705.04 Welded wire fabric


Construction Requirements 615.03 Membrane Waterproofing. Membrane waterproofing shall be a firmly bonded membrane composed of two layers of asphalt-treated fabric and three moppings of asphalt or two layers of tar-treated fabric and three moppings of tar, together with a coating of primer, all applied as follows:

All concrete surfaces which are to be waterproofed shall be smooth and shall be free of projections or depressions that might cause puncture of the membrane.

The surface shall be dry and free of dust and loose materials immediately before the application of the waterproofing. Waterproofing shall not be done in wet or freezing weather without written authorization from the Engineer.

Asphalt shall be applied at a temperature between 300° and 350° F., and tar between 200° and 250° F.

A coating of primer shall be applied and allowed to dry before any mop coat is applied.

The fabric shall be so laid that drainage will be over, and not against or along, the laps. It shall be “shingled" so that there will be two thicknesses at all points. Edge laps shall be at least 4 inches and end laps at least 12 inches. One ply of fabric shall not touch another or the primed concrete surface since there must be three unbroken moppings.

Beginning at the lowest point of the surface to be waterproofed, a primed section about 20 inches wide shall be mopped with the hot asphalt or tar. A strip of fabric of half the width of the roll shall be placed immediately on the hot asphalt or tar and pressed carefully into place so as to expel all entrapped air and obtain close conformity with the surface. This strip and an adjoining area of concrete surface, slightly

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