molds as soon as practicable and shall be kept damp for a period of at least ten (10) days. Any member that shows checking of soft corners of surfaces shall be rejected.
Expansion joints shall be constructed as to permit freedom of movement. After all work is completed, all loose or thin shells of mortar likely to spall under movement shall be carefully removed from all expansion joints by means of a sharp chisel.
401.3.4 Wooden Railing
Wooden railing shall be constructed in accordance with the requirements of Item 402, Timber Structures.
401.3.5 Stone and Brick Railing
The materials used in masonry brick railing and parapet and the work to be done shall conform to the requirements of this Specification. The workmanship shall be first class and the finished construction shall be neat in appearance and true to line and grade.
401.4 Method of Measurement
The quantity to be paid for shall be the number of linear meters of specified railing actually completed and accepted measured from center to center of end posts.
401.5 Basis of Payment
The accepted quality, measured as prescribed in Section 401.4, shall be paid for at the contract unit price for Railing, which price and payment shall be full compensation for furnishing and placing all materials including all labor, equipment, tools and incidentals necessary to complete this Item.
Payment will be made under:
Pay Item Number
Description
Unit of Measurement
401 Railing Meter
ITEM 402 – TIMBER STRUCTURES
402.1 Description
This Item shall consist of the construction of timber structures to the dimensions, lines and grades as shown on the Plans or as ordered by the Engineer in accordance with these Specifications. The timber shall be treated or untreated as called for on the Plans or Special Provisions.
402.2 Material Requirements
402.2.1 Timber
It shall conform to the requirements of Item 713, Treated and Untreated Timber.
402.2.2 Hardware
All hardware shall be of the kind and size specified on the Plans. All bolts, including drift bolts, shall be either wrought iron or medium steel. Washers shall be either ogee gray iron casting or malleable cast iron unless cut washers are specified on the Plans.
Bolts shall have square heads and nuts, unless otherwise specified. Nails shall be cut or round wire of standard form. Spikes shall be cut wire or spikes, or boat spikes, as specified. All hardware shall be galvanized in conformity with AASHTO M 232 or cadmium plated per ASTM M 165 Type OS, unless otherwise specified on the Plans or Special Provisions.
402.2.3 Paint
It shall conform to the requirements of Item 709, Paints or Item 411, Paint.
402.2.4 Structural Steel
It shall conform to the applicable requirements of Item 712, Structural Metal.
402.2.5 Preservatives
The preservative shall be creosote oil or creosote petroleum oil blend as called for on the Plans or by the Special Provisions, and shall conform to the Specifications for timber preservatives of the AASHTO M 133.
When timber is intended for marine use, creosote petroleum oil blend shall not be used.
402.3 Construction Requirements
402.3.1 Storage of Materials
All timber which is to be stored on the job for any length of time prior to its use in the structure shall be neatly stacked in piles to prevent warping or distortion. Untreated timber shall be open-stacked at least 300mm above the ground and the stack shall be sloped so as to shed water. Creosote-treated timber shall be close-stacked and piled to prevent warping. The ground underneath and in the vicinity of all material piles shall be cleared of all weeds and rubbish.
402.3.2 Treated Timber
All treated timber shall be framed prior to treating. Care shall be exercised in handling all treated timber so as not to break or penetrate the treatment with any tool or handling equipment. Any piece of timber that has been damaged by the Contractor shall be replaced by him without extra compensation.
Any cut made or hole bored in treated timber that shall expose untreated wood shall be given three coats of hot creosote or carbolineum before the exposed part is assembled.
402.3.3 Timber Treatment
Treatment shall consist of the forcing of either creosote oil or a creosotepetroleum oil mixture into the outer fibers of the timber by a heat and pressure process. The treatment shall be so regulated that the curing process will not induce excessive checking.
The minimum penetration of the preservative with the surface of the timber shall be 20mm. The minimum retention of preservative per cubic metre of timber shall be as follows:
For general use, 195 kg by empty cell process
For marine use, 320 kg by full cell process
The Engineer shall be notified at least ten (10) days in advance of the date that the treating process will be performed in order that the untreated timber, the treatment process, and the finished treated timber may all be inspected. The Engineer will inspect the timber prior to treatment to determine conformance with the Specifications and suitability of conditions for treatment.
He shall be permitted free access to the plant in order that temperatures, pressures and quantities and types of treatment materials used may be observed. Samples of the creosote or creosote-petroleum mixture shall be furnished as required for tests.
After completion of the treatment, the timber shall be checked to determine penetration of treatment, amount of checking, quantity of free preservative remaining of the timber and any other visual evidence that the treatment has been performed in a satisfactory manner. The penetration of treatment shall be determined by boring a sufficient number of well-distributed
holes to determine the average penetration. All such holes shall be plugged with plugs approximately 2mm larger in diameter than the bit used in boring the holes.
If the penetration of preservative is less than the required amount, the entire charge, or such parts thereof as are determined by the Engineer or his authorized representative to be unsatisfactory, may be retreated. If after retreatment, the penetration is still insufficient, the retreatment pieces shall be rejected.
Any excessive checking caused by the treating process shall be cause for rejection of the pieces in which the excessive checking occurs.
The treating plant shall be equipped with adequate thermometers and pressure gages so that the process can be accurately controlled and a continuous record made of stages of the treating process. If requested by the Engineer, records shall be furnished showing the duration, maximum and minimum temperatures and pressures used during all stages of the process.
402.3.4 Untreated Timber
In structures of untreated timber, all of the following surfaces shall be coated thoroughly with two (2) coats of hot creosote oil or carbolineum before the timber are assembled: ends, tops and all contact surfaces of posts, sills, caps, floor beams and stringers, all ends, joints and contact surfaces of bracing.
The back surface of all bulkheads and any other timber in direct contact with earth shall be similarly treated.
402.3.5 Bolts and Washers
Washers of the size and type specified shall be used under all bolt heads and nuts that would otherwise be in contact with wood. Cast iron washers shall have a thickness equal to one fourth the diameter of the bolt and the diameter of the washer shall be four times its thickness. For malleable or plate washers, the diameter or side size of the square shall be equal to four times the diameter of the bolt. Cap washers shall be used when the timber is in contact with earth. All nuts shall be checked effectively after being finally tightened.
402.3.6 Pile Bents
The pile shall be driven as indicated on the Plans, with a variation of the portion above the ground of not more than 6mm per 300mm from the vertical or batter indicated, or so that the cap may be placed in its proper location without inducing excessive stresses on the piles. Excessive manipulation of piles will not be permitted and the Contractor will be required to redrive or use other satisfactory methods to avoid such manipulations. No shimming on tops of piles will be permitted.
The piles for any one bent shall be carefully selected as to size and quality to avoid undue bending or distortion of the sway bracing. However, care shall be exercised in the distribution of piles of various sizes to secure uniform
strength and rigidity in the bents of any given structure. Cut offs shall be accurately made to insure perfect hearing between caps and piles.
402.3.7 Frame Bents
Concrete pedestal for the support of framed bents shall be finished carefully so that sills or posts will take even bearing on them. Dowels for anchoring sills or posts shall be set the concrete is cast and shall project at least 150mm above the tops of the pedestals.
Sills shall have true and even bearing on piles or pedestals. They shall be drift-bolted with bolts extending into the piles or pedestals at least 150mm.
When possible, all earth shall be removed from contact with sills so that there will be free circulation of air around the sills.
402.3.8 Caps
Timber caps shall be placed to obtain even and uniform bearing over the tops of the supporting posts or piles with their ends in alignment. All caps shall be secured by driftbolts, set approximately at the center extending at least 230mm into the post or piles.
402.3.9 Bracing
Bracing shall be bolted through at intersections to the pile, posts, caps or sills.
402.3.10 Stringers
Stringers shall be sized at bearings and shall be placed in position so that knots near the edges will be in the top portions of the stringers. Outside stringers may have butt joints but interior stringers shall be lapped to take bearing over the full width of the floor beam or cap at each end. The lapped ends of untreated stringers shall be securely fastened to caps by driftbolts.
When stringers are two panels in length, the joints shall be staggered. Cross-bridging between stringers shall be neatly and accurately framed and securely toe-nailed with at least two nails at each end. All cross-bridging members shall have full bearing at each end against the sides of stringers. Unless otherwise specified, cross bridging shall be placed at the center of each span.
402.3.11 Plank Floors
Roadway and sidewalk floor planks, unless otherwise stipulated, shall be surfaced one side and one edge (SISIE). The planks shall be laid heartside down, with 7mm openings between them for seasoned materials and with tight joints for unseasoned material. Each plank shall be spiked securely to each joint or supporting member. The planks shall be graded carefully as to thickness, and so laid that no two adjacent planks shall vary in thickness by more than 1.6mm.
402.3.12 Laminated or Strip Floors
Planks for laminated or strip floors shall have a nominal thickness of 50mm and shall be surfaced to a uniform width (SIE), and when so specified, to a uniform thickness (SIS). Unless otherwise stipulated, no splicing of planks will be allowed.
Planks shall be laid with the surfaced edge down and each plank shall be toe-nailed to each alternative stringer. The nailing of successive planks shall be staggered so that the spacing of nails along each stringer shall not be less than 100mm. In addition, each piece shall be nailed horizontally to adjacent pieces at 450mm centers, and staggered both horizontally and vertically with nails in adjacent pieces. All floors shall be cut to a straight line along the sides of the roadway.
402.3.13 Railing and Rail Posts
Railing and rail posts shall be built as shown on the Plans and shall be constructed in a workmanlike and substantial manner. All railing and rail post materials shall be surfaced on four sides (S4S). All rails shall be continuous and squarely butt-joined at the post.
402.3.14 Wheel Guards
Wheel guards shall be accurately constructed true to line and grade in accordance with the Plans.
Unless otherwise specified, wheel guards shall be surfaced on one side and one edge (SISIE). Wheel guards shall be laid in sections not less than 3.60mm long.
402.4 Method of Measurement
Timber structures shall be measured by the completed span and shall include all materials, equipment and labor used to finish the structure as called for in the Bid, Plans and Specifications.
402.5 Basis of Payment
Payment for the timber structure measured in Section 402.4, Method of Measurement, shall constitute full compensation for furnishing all materials, preservative treatment, if called for in the Contract, equipment, hardware and other metal parts, tools and labor necessary for the completion of the structure and painting, if required in a satisfactory manner and all incidentals necessary to complete the Item.
Payment will be made under:
Pay Item Number
Description
Unit of Measurement
402 (1) Timber Structure Span
ITEM 403 – METAL STRUCTURES
403.1 Description
This work shall consist of steel structures and the steel structure portions of composite structures, constructed in reasonably close conformity with the lines, grades and dimensions shown on the Plans or established by the Engineer.
The work will include the furnishing, fabricating, hauling, erecting, welding and painting of structural metals called for in the Special Provision or shown on the Plans. Structural metals will include structural steel, rivet, welding, special and alloy steels, steel forgings and castings and iron castings. This work will also include any incidental metal construction not otherwise provided for, all in accordance with these Specifications, Plans and Special Provisions.
403.2 Material Requirements
Materials shall meet the requirements of Item 712, Structural Metal; Item 409, Welded Structural Steel, and Item 409, Welded Structural Steel; and Item 709, Paints.
403.3 Construction Requirements
403.3.1 Inspection
The Contractor shall give the Engineer at least fifteen (15) days notice prior to the beginning of work at the mill or shop, so that the required inspection may be made. The term “mill” means any rolling mill, shop or foundry where material for the work is to be manufactured or fabricated. No material shall be rolled or fabricated until said inspection has been provided.
The Contractor shall furnish the Engineer with copies of the certified mill reports of the structural steel, preferably before but not later than the delivery of the steel to the job site.
The Contractor shall furnish all facilities for inspection and the Engineer shall be allowed free access to the mill or shop and premises at all times. The Contractor shall furnish, without charge, all labor, machinery, material and tools necessary to prepare test specimens.
Inspection at the mill or shop is intended as a means of facilitating the work and avoiding errors and it is expressly understood that it will not relieve the Contractor from any responsibility for imperfect material or workmanship and the necessity for replacing same. The acceptance of any material or finished member at the mill or shop by the Engineer shall not preclude their subsequent rejection if found defective before final acceptance of the work. Inspection of welding will be in accordance with the provision of Section 5 of the “Standard
Code for Arc and Gas Welding in Building Construction” of the American Welding Society.
403.3.2 Stock Material Control
When so specified in the Contract, stock material shall be segregated into classes designated as “identified” or “unidentified”. Identified material is material which can be positively identified as having been rolled from a given heat for which certified mill test can be produced. Unidentified material shall include all other general stock materials. When it is proposed to use unidentified material, the Engineer shall be notified of such intention at least fifteen (15) days in advance of commencing fabrication to permit sampling and testing. When so indicated or directed, the Contractor shall select such material as he wishes to use from stock, and place it in such position that it will be accessible for inspection and sampling. The Contractor shall select identified material from as few heat numbers as possible, and furnish the certified mill test reports on each of such heat numbers. Two samples shall be taken from each heat number as directed, one for a tension test and one for a bend test.
In the case of unidentified stock, the Engineer may, at his discretion, select any number of random test specimens.
Each bin from which rivets or bolts are taken shall subject to random test.
Five rivets or bolts may be selected by the Engineer from each bin for test purposes.
Structural material, either plain or fabricated, shall be stored above the ground upon platforms, skids, or other supports. It shall be kept free from dirt, grease, or other foreign matter, and shall be protected as far as practicable from corrosion.
403.3.3 Fabrication
These Specifications apply to riveted, bolted and welded construction.
The Contractor may, however, with approval of the Engineer, substitute high tensile strength steel bolts equivalent to the rivets in any connection.
Workmanship and finish shall be in accordance with the best general practice in modern bridge shops. Portions of the work exposed to view shall be finished neatly. Shearing, flame cutting, and chipping shall be done carefully and accurately.
Structural material, either plain or fabricated, shall be stored above the ground upon platforms, skids or other supports. It shall be kept free from dirt, grease or other foreign matter, and shall be protected as far as practicable from corrosion.
Rolled material before being laid off or worked must be straight. If straightening is necessary, it shall be done by methods that will not injure the metal. Sharp kinks and bends will be cause for rejection of the material.
Welding Society) D 1.1, paragraph 3.2 as modified by AASHTO Standard Specification for Welding of Structural Steel Highway Bridges.
403.3.4 Finishing and Shaping
Finished members shall be true to line and free from twists, bends and open joints.
1. Edge Planing
Sheared edges of plates more than 15.9 mm in thickness and carrying calculated stresses shall be planed to a depth of 6.3 mm.
Re-entrant cuts shall be filleted before cutting.
2. Facing of Bearing Surfaces
The surface finish of bearing and based plates and other bearing surfaces that are to come in contact with each other or with concrete shall meet the American National Standards Institute surface roughness requirements as defined in ANSI B-46.1-47, Surface Roughness Waviness and Lay, Part I:
Steel slabs ANSI 2,000
Heavy plates in contact in shoes to
Be welded ANSI 1,000
Milled ends of compression members,
stiffeners and fillers
ANSI 500 Bridge rollers and rockers ANSI 250
Pins and pin holes ANSI 125
Sliding bearings ANSI 125
3. Abutting Joints
Abutting joints in compression members and girders flanges, and
Abutting joints in compression members and girders flanges, and