Timber Structures Art. 507.03 When paid for as a separate item, cleaning and painting of steel railings will be measured for payment in place in feet (meters). The length measured will be the overall length along the top longitudinal rail element through all posts and gaps.
506.12 Basis of Payment. Cleaning and painting in connection with the
fabrication and erection of steel structures will not be paid for separately but shall be considered as included in the contract unit price or prices for furnishing, fabricating and erecting, or installing the material. The field cleaning and painting of newly erected structural steel under a contract separate from the fabrication and erection will be paid for at the lump sum price for CLEANING AND PAINTING STRUCTURAL STEEL, at the location specified. The field cleaning and painting of steel railings which are fabricated and erected at the contract unit price per foot (meter) will be paid for at the contract unit price per foot (meter) for PAINTING STEEL RAILING when performed under a contract separate from the erection. SECTION 507. TIMBER STRUCTURES
507.01 Description. This work shall consist of timber construction required
for bridges and appurtenances, where the timber is incorporated in the completed structure. All lumber and timber for erection purposes, such as falsework, forms, sheeting, bracing, etc., are not subject to the requirements of this Section.
507.02 Materials. Materials shall be according to the following.
Item Article/Section
a.Structural Timber ................................................................................ 1007.03
b.Preservative Treatment ..................................................................... 1007.12
c.Fastenings for Timber Structures ....................................................... 1006.17
d.Structural Steel .................................................................................. 1006.04
e.Asphalt Binder (Note 1) ........................................................................... 1032
f.Fine Aggregate .................................................................................. 1003.03
g.Structural Steel Coatings ................................................... 1008.01 - 1008.02 Note 1. The asphalt binder shall be Grade PG 52-28, PG 58-28, or PG 58-22. Structural steel and other metals requiring fabrication shall be fabricated according to Section 505. CONSTRUCTION REQUIREMENTS
507.03 Storage of Materials. Untreated lumber at the site of the work shall
be open-stacked on supports at least 12 in. (300 mm) above the ground and shall be so stacked and stripped as to permit free circulation of air between the tiers and courses. When required by the Engineer, it shall be protected from the weather by suitable covering. Treated timber shall be close-stacked according to Article 1007.13. Art. 507.04 Timber Structures
507.04 Workmanship. All timber shall be accurately cut and framed to a
close fit in such manner that the joints will have even bearing over the entire contact surfaces. Nails and spikes shall be driven just sufficiently to set the heads flush with the surface of the wood. Deep hammer marks in wood surfaces shall be considered evidence of poor workmanship.
507.05 Treated Timber. All cutting, framing and boring of treated timber shall
be done before treatment insofar as is practicable.
a.Handling. Treated timber shall be handled carefully without sudden dropping, bruising, breaking of outer fibers or penetrating the surface with tools. It shall be handled with rope slings. Cant hooks, peaveys, pikes, or hooks shall not be used.
b.Cuts, Abrasions, and Holes. All cuts, abrasions, and holes made after treatment shall be repaired according to Article 1007.13. Each coat shall be allowed to dry before the next coat is applied. Any unfilled holes, after being treated with preservative, shall be plugged with treated plugs.
c.Temporary Attachments. Forms or temporary braces may be attached to treated timber with nails or spikes only when approved by the Engineer. Upon their removal, the holes shall be filled by driving galvanized nails or spikes flush with the surface, or by plugging as required for holes.
507.06 Countersinking. Countersinking shall be done wherever smooth
faces are required. Recesses formed in treated timber for countersinking shall be treated as required for cuts and abrasions, except as specified for plank floors.
507.07 Hardware. The term hardware shall include all metal fastenings
required for timber connections or for connecting timber to concrete or steel work. The following items will be considered as hardware: bolts, tie rods, turnbuckles, washers, nuts, drift bolts, steel dowels, nails, spikes, and lag screws for timber connections; steel plates used as washers or between timber caps and the tops of piles or timbers; metal timber connectors of various designs; metal shear developers for composite timber and concrete floors; and anchor plates or clips for plank floors and sidewalks. Sheet metal pile coverings and steel traffic treads and their fastenings are not considered hardware. All hardware for treated timber construction, except cast iron ogee washers, malleable iron washers and timber connectors, shall be stainless steel or galvanized.
a.Rods. Rods connecting only sawed timbers shall be threaded sufficiently at each end to provide tight connections, allowing for permissible variations in dimensions of material. All rods shall extend entirely through the nut at each end and, after being drawn tight, all ends that project more than 1 in. (25 mm) beyond the nut shall be cut off about 1/2 in. (13 mm) beyond the nut.
b.Bolts. The length specified shall be the length measured under the head. Bolts may be substituted for rods for timber connections where the length of threaded portion provided by the bolt is sufficient. Bolt ends projecting more than 1 in. (25 mm) beyond the nut shall be cut off as specified for rods. Timber Structures Art. 507.08 Special flat head bolts, or carriage bolts, shall be used for connections horizontally through railings and wheel guard timbers, with the head at the roadway face of the timbers. Machine bolts with square heads and nuts shall be used for other connections.
c.Lag Screws. Lag screws shall be installed by turning them into place. They may be driven sufficiently to start them into the holes and hold them firmly in place for turning, but shall not be driven beyond the depth that will be occupied by the shank.
d.Nuts and Washers. Washers shall be used under all nuts and bolt heads that would otherwise come in contact with wood, except under large diameter heads of specially designed flat head bolts. Ogee or malleable iron washers shall be used for all tie rods except where plate washers are called for by the plans, and for all rods and bolts passing through piles except bolts connecting railing plank to wing piles. Standard wrought washers shall be used at all locations, except where washers of other types are required. All nuts shall be standard square nuts. They shall be tightened sufficiently to prevent the rods or bolts from becoming loose during service and, after being tightened, they shall be effectively secured against backing off by burring of the rod or bolt threads.
e.Nails and Spikes. Nails shall not extend through all material into which they pass. The size of nails and spikes, when not otherwise shown, shall be according to the following. Size of Nails and Spikes Actual Thickness of Piece Nailed in. (mm) Actual Thickness of Piece Nailed to in. (mm) Size of Nails and Spikes 1 5/8 (41) 1 5/8 (41) 10d 1 5/8 (41) 2 (50) 16d 1 5/8 (41) 2 5/8 (66) or more 20d 2 (50) 2 (50) 16d 2 (50) 2 5/8 (66) or more 20d 2 5/8 (66) 2 5/8 or 3 (66 or 75) 40d 2 5/8 (66) 3 5/8 (92) or more 60d 3 (75) 3 (75) 50d 3 (75) 3 5/8 (92) or more 60d 3 5/8 (92) 3 5/8 (92) Spikes 4 (100) 3 5/8 (92) or more 7 in. (178 mm) spikes
507.08 Holes for Bolts, Dowels, Rods, and Lag Screws. Holes for round
drift bolts and dowels shall be bored with a bit 1/16 in. (2 mm) less in diameter than the bolt or dowel to be used. The diameter of holes for square drift bolts or dowels shall be equal to the least dimension of the bolt or dowels. Holes for bolts shall be bored with a bit of the same diameter as the bolt. Holes for rods shall be bored with a bit 1/16 in. (2 mm) greater in diameter than the rod. Holes for lag screws shall be bored with a bit not larger than the body of the screw at the root of the thread. If Art. 507.09 Timber Structures required to prevent splitting, the hole for the shank shall be bored the same diameter as the shank. The depth of holes for lag screws shall be a minimum of 1 in. (25 mm) less than the length under the head.
507.09 Pile Bents and Abutments. All work involving piles shall be
according to Section 512. Cut-offs shall be made accurately to ensure complete bearing between the cap and piles, or good alignment of the tops of wing piles. No shimming between pile tops and caps will be permitted, except to provide for adjustment of not more than 1 in. (25 mm) required on account of errors in cut-off. The shim for this purpose shall consist of a single square steel plate of the proper thickness, having the same width as the cap, punched 1/16 in. (2 mm) larger than the drift bolt. The piles for any one bent or line shall be selected carefully as to size, to avoid undue bending or distortion of the bracing or backing timbers. Care shall be exercised in the distribution of piles of varying sizes to secure the required strength and rigidity throughout the structure.
507.10 Caps. Timber caps shall be placed, with ends aligned, in a manner to
secure an even and uniform bearing on the tops of the supporting posts or piles. They shall be secured by a drift bolt not less than 3/4 in. (19 mm) in diameter, extending at least 9 in. (225 mm) into each post or pile. The drift bolt shall be as near the center of the post or pile as possible without interfering with rods passing through the post or pile near the cap. Caps shall not be spliced, except as provided by the plans.
507.11 Backing Plank. Backing plank shall be placed so that exposed ends
form a straight line. They shall be fastened to each pile and nailing strip with at least two nails or spikes. Splices in backing plank shall be made at the center of a pile and splices in adjoining lines or plank shall be staggered. Backing plank for wings shall be placed so that the top of the top plank will be at the proper elevation.
507.12 Stringers. Timber stringers shall be placed in position so that the floor
will have an even bearing on all stringers and so that any knots near edges will be in the top portions of the stringers. Outside stringers may have butt joints, centered over caps or floor beams, but interior stringers shall be lapped to take bearing over the full width of the cap or floor beams at each end. Stringers shall be toenailed to caps and intermediate stringers of adjoining spans shall be spiked together where they lap. Cross-bridging between stringers shall be neatly and accurately framed, and securely toenailed with at least two nails in each end. All cross-bridging members shall have full bearing at each end against the sides of stringers. 2 in. (50 mm) by 4 in. (100 mm) cross-bridging shall be placed at the center of each span.
507.13 Plank Floors. The floor planks shall be laid at right angles to
centerline of roadway. The planks shall be carefully graded as to thickness and laid so that no two adjacent planks will vary in thickness by more than 1/16 in. (2 mm). When more than one length of plank is required, joints between abutting ends shall be staggered at least 3 ft (1 m) in any two adjacent lines of plank. Ends of planks at the edges of the roadway shall be cut on a straight line parallel with the centerline of the roadway. Timber Structures Art. 507.15 When plank floors on steel stringers are to be fastened to nailing strips bolted to the sides of the steel stringers, the top of each nailing strip shall be flush with the top of the beam or channel. A recess of the proper width and depth shall be provided in the top surface of the nailing strip to fit neatly around the projecting flange of the beam or channel. Nailing strips for treated plank floors shall be so recessed before treatment. In constructing floors of untreated material, the planks shall be laid heart side down with 1/4 in. (6 mm) joints between them for seasoned material and with tight joints for unseasoned material. Treated plank floors shall be laid with tight joints, except when the planks are separated by anchor clips used for fastening the planks to steel stringers. Standard wrought washers shall be used under the heads of all lag screws and the heads or nuts of all machine bolts used for fastening the floor plank. Where machine bolts are used for fastening the floor plank, all nuts used shall be locknuts. Heads of all lag screws and bolts in the surface of the floor shall be countersunk so that the tops will be flush with the surface of the plank. Recesses formed for countersinking shall be just large enough to admit the washers and, after the lag screw or bolt is in place, shall be filled with hot pitch. For laminated or strip floors, the strips shall be placed on edge and each strip shall be nailed to the preceding strip at each end with two nails and approximately at 18 in. (450 mm) intervals with nails driven alternately near the top and bottom edges. The nails shall be long enough to pass through two strips and at least halfway through the third strip. If timber stringers or nailing strips are used, every other strip shall be toenailed to every other support. Care shall be taken to have each strip vertical and tight against the preceding one, and bearing evenly on all supports.
507.14 Bituminous Surface Coat. When required, plank floors shall be given
a bituminous surface coat. The floor shall be cleaned of foreign materials and the asphalt cement shall be applied at a temperature of from 275 to 350 °F (135 to 175 °C) and at a rate of approximately 1/4 gal/sq yd (1 L/sq m) of surface. The plank shall be dry at the time of this application. The entire surface shall then be covered with a thin coating of fine aggregate, sufficient in quantity to take up any free bitumen.
507.15 Steel Traffic Treads. Steel traffic treads shall be not less than 3/16 in.
(5 mm) thick, exclusive of the raised portions, not less than 24 in. (600 mm) wide, and the individual sections not more than 15 ft (4.5 m) long. Treads shall have a non-skid surface with alternate projections at right angles to each other. The raised portions shall be formed in the rolling and not by punching or pressing from the underside. Treads shall be punched 7/16 in. (11 mm) for lag screws or bolts. The holes shall be placed not less than 1 1/4 in. (30 mm) nor more than 1 1/2 in. (40 mm) from the edge of the tread. The spacing of holes on both sides of the tread shall be not more than 15 in. (375 mm) and on both ends of each section not more than 6 in. (150 mm). The unit weight of the treads shall be approximately 8 3/4 lb/sq ft (43 kg/sq m). Before the treads are laid, all high spots and rough spots in the plank floor shall be removed so that the treads will be in contact with the floor for their full length and width. Treads shall be laid in a heavy mop coat of hot asphalt according to
Article 1032 — 11, PAF-3. Treads shall be laid with a space of 1/4 in. (5 mm) between
adjacent ends and shall be fastened by means of 3/8 in. (M10) galvanized bolts. Art. 507.16 Timber Structures Where bolts cannot be installed, 3/8 in. by 3 in. (M10 by 75 mm) galvanized screws shall be used.
507.16 Wheel Guards and Railings. Wheel guards and railings shall be
accurately framed so that they will be true to line and grade. Wheel guards shall be laid in sections not less than 12 ft (3.6 m) long with each splice located approximately over the center of a scupper block. Railing plank shall be untreated timber and shall be painted with two coats of white paint. Surfaces in contact with rail posts or piles shall be painted with one coat before the railing planks are erected.
507.17 Method of Measurement. This work will be measured for payment as
follows.
a.Contract Quantities. The requirements for the use of Contract Quantities shall conform to Article 202.07(a).
b.Measured Quantities. The quantity of timber will be computed in foot board measure (cubic meters). Computations of quantity will be based on the nominal commercial widths and thicknesses of the material. The length will be the actual lengths of the various pieces required, measured to the nearest 1 in. (25 mm). The length of each piece with a beveled end will be taken as the overall length of the piece, except that when two or more pieces with beveled ends may be cut economically from a single commercial length, the sum of the lengths will not exceed the commercial length required. The quantity computed for payment will include all splices required by the plans but will not include any allowance for additional splices or waste. Hardware will be measured for payment in pounds (kilograms). The weight (mass) of rods and plates will be computed from the weights (masses) shown in the American Institute of Steel Construction Manual, with no deduction for holes and no allowance for overrun. Weights (masses) computed from dimensions of material will be based upon a weight (mass) of 490 lb/cu ft (7850 kg/cu m) for steel, 485 lb/cu ft (7770 kg/cu m) for wrought iron, and 450 lb/cu ft (7200 kg/cu m) for cast iron. No additional allowance for loss or waste will be added to the computed weights (masses), but an additional allowance of 3 1/2 percent for galvanizing will be added to weights (masses) of all galvanized material computed on the basis of ungalvanized material. Bituminous surface coat for plank floors will be measured for payment in square yards (square meters). Steel traffic treads will be measured for payment in square feet (square meters).
507.18 Basis of Payment. Treated timber will be paid for at the contract unit
price per foot board measure (cubic meter) for TREATED TIMBER. Untreated timber will be paid for at the contract unit price per foot board measure (cubic meter) for UNTREATED TIMBER. All items classed as hardware will be paid for at the contract unit price per pound (kilogram) for HARDWARE. Bituminous surface coat for plank floors will be paid for at the contract unit price per square yard (square meter) for Reinforcement Bars Art. 508.04 BITUMINOUS SURFACE COAT. Steel traffic treads, including bolts, lag screws, or other fastenings, will be paid for at the contract unit price per square foot (square meter) for STEEL TRAFFIC TREADS. SECTION 508. REINFORCEMENT BARS
508.01 Description. This work shall consist of furnishing and placing
reinforcement bars.
508.02 Materials. Materials shall be according to the following.
Item Article/Section
a.Reinforcement ................................................................................... 1006.10
b.Concrete Brick (Note 1) ................................................................. 1042.15(b)
c.Bar Splicer Assemblies or Mechanical Splicers ..................... 1006.10(a)(1)g. Note 1. In lieu of a certified precast concrete producer, product from a local supplier will be accepted. CONSTRUCTION REQUIREMENTS
508.03 Storage, Protection, and Handling. Reinforcement bars shall be
stored off the ground using platforms, skids, or other supports; and shall be protected from injury and from deterioration by exposure. Epoxy coated reinforcement bars shall be stored on wooden or padded steel cribbing and all systems for handling shall have padded contact areas. The bars or bundles shall not be dragged or dropped. When epoxy coated bars are stored in a manner where they will be exposed to the weather more than 60 days prior to use, they shall be protected. The protection shall consist of covering with opaque polyethylene sheeting or other suitable opaque material. The covering shall be secured and allow for air circulation around the bars to minimize condensation under the cover. Covering of the epoxy coated bars will not be required when the bars are installed and tied, or when they are partially incorporated into the concrete. However, partially incorporated epoxy coated bars shall be protected if they will be exposed to weather until the next construction season.
508.04 Cutting and Bending. Reinforcement bars shall be cut and bent at
the mill or shop to the shapes shown on the plans before shipment to the work. Bending in the field will not be permitted, except to correct errors, damage by handling and shipping, and minor omissions in shop bending. Epoxy coated reinforcement bars that are specified to be cut in the field shall be either sawed or sheared but shall not be flame cut. Patching and repair of the cut, bent, or damaged epoxy coated reinforcement bars shall be completed using a two- part epoxy according to ASTM D 3963 (D 3963M).
Referenced in this section
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Source: Illinois Standard Specifications for Road and Bridge Construction, 2022 Edition. Pages 398–404 of 1,217. View official source ↗