480 Page 356480 REINFORCING STEEL
480.1DESCRIPTION
This work consists of furnishing and placing steel of the specified size and type, as reinforcement in concrete.
480.2MATERIAL
Reinforcement will conform to Section 1010 . Reinforcement will be furnished in the full lengths indicated on the plans.
480.3CONSTRUCTION REQUIREMENTS
A.Protection of Material : Steel reinforcement will be protected from damage and when placed in the work, steel reinforcement will be free from dirt, detrimental scale, paint, oil, and other foreign substance. Steel reinforcement will be stored above ground on platforms, skids, or other supports. When epoxy coated steel reinforcement is specified, the following requirements also apply: 1.In order to protect the coated reinforcement from damage, the Contractor will use padded or non-metallic slings or straps to load, unload, or move epoxy coated reinforcement. 2.Bundled bars will be handled in a manner as to prevent excessive sagging of the bars so as not to damage the epoxy coating. 3.To prevent damage to the epoxy coating, care will be taken during placement of epoxy coated reinforcement to ensure the bars are not dropped or dragged. 4.Damaged areas will be repaired by removing all rust and contaminants from the damaged area and applying an epoxy coating to the damaged area. The touch up epoxy coating material will be inert in concrete and compatible with the original epoxy coating and the reinforcing steel. This coating material will be epoxy coating touch up material supplied by an epoxy coating manufacturer who supplies coating material for new epoxy coated reinforcing steel. Touch up epoxy coatings from spray cans will not be permitted. The touch up epoxy coating will be allowed to cure for a minimum of 24 hours or as per the manufacturer's recommendations, whichever is more stringent, before concrete is placed. 5.Epoxy coated reinforcing steel will be covered with a heavy duty waterproof opaque covering to protect the epoxy coating from dirt and debris and from the effects of ultraviolet rays if the reinforcing steel will be stored for more than 30 calendar days. B.Bending: Reinforcement will be bent to the shapes specified. Bending and bundling will conform to the standard practice currently specified by the Concrete Reinforcing Steel Institute. C.Placing and Fastening: Reinforcing steel will be accurately placed in accordance with the tolerances of ACI 117 and firmly held in the positions specified using steel chairs or other approved methods. Bars will be tied at all intersections (100%) when spacing is 1 foot or 480 Page 357more in any direction (longitudinal, vertical, or horizontal), otherwise a minimum of every other intersection (50%) will be tied. All lap splices shown are contact lap splices unless specifically noted otherwise. 1.General: Distances from the forms will be maintained by stays, blocks, ties, chairs, or hangers. Devices for holding reinforcement from contact with the forms will be of approved shape and dimensions. Layers of bars will be separated by approved metal devices. The use of pebbles, stone, brick, metal pipe, and wooden blocks will not be permitted. Wire bar supports, such as ferrous metal chairs and bolsters, will conform to industry practice as described in the manual of Standard Practice of the Concrete Reinforcing Steel Institute. Chairs or bolsters which bear against the forms for exposed surfaces will be either Class 1 - Maximum Protection (plastic protected) or Class 2 - Moderate Protection, Type B (stainless steel tipped) for which the stainless steel conforms to ASTM A493, Type 430. Chairs or bolsters which are earth bearing will be Class 3 - No Protection (bright basic bar supports). For epoxy coated reinforcement, all wire bar supports and bar clips will be plastic or epoxy coated. Chair spacing will not exceed 3 feet 6 inches in either direction. If plastic chairs are used, chair spacing will not exceed 2 feet 6 inches in either direction. The Engineer may require a closer chair spacing for mat rigidity. Tie wires will be black annealed 16 1/2 gauge or heavier. Ties will be plastic coated when used in conjunction with epoxy coated reinforcing steel. Welding of reinforcing steel will not be allowed without written approval of the Bridge Construction Engineer. The request for approval will list the bars to be welded, welding procedure, type of electrode, joint detail, and mill certificate of the reinforcing steel to be welded. Reinforcement will be inspected and approved, before the placing of concrete begins. The placing of any reinforcement except mesh during the process of placing the concrete will not be permitted. Concrete placed in violation of this provision may be rejected and ordered removed. 2.Structures: When placing bridge deck and box culvert reinforcement either slab bolster (SB) or beam bolster (BB) bar supports will be used between the mats or reinforcement and the form work. Either slab bolster upper (SBU) or beam bolster upper (BBU) bar supports will be used between mats of reinforcing steel. Individual high chair (HC) bar supports will not be used. On girder bridges either slab bolster upper (SBU) or beam bolster upper (BBU) bar supports will be used between mats of reinforcement and placed transverse to the girders. Slab bolsters (SB) or beam bolsters (BB) will be used under the bottom mat placed parallel to the girders. 480 Page 358The top mat of bridge slab and box culvert reinforcement will be tied down with 16 1/2 gauge diameter (minimum) tie wires or other approved devices. It will not be permissible to tack weld reinforcement. On girder bridges, ties will be used along each line of beams at longitudinal intervals not to exceed 8 feet. The ties will be secured to the shear transfer devices protruding from the top of the beam. Where shear transfer devices are not available, the ties may be secured to the bottom mat of slab reinforcing steel. Other types of bridges and box culverts the top mat of reinforcement will be tied down at a maximum of 12 foot longitudinal and transverse intervals with the ties secured to either the forms or bottom mat of slab reinforcing steel. 3.Continuous Reinforced Concrete Pavement: On continuous reinforced concrete pavement, the Contractor will use continuous high chair (CHCP) and beam bolsters (BBP) with earth- bearing bases or sand plates (P) or an approved alternate. Individual high chair (HC) bar supports will not be used. D.Mechanical Bar Splices Mechanical bar splices will only be used when specified in the plans or approved by the Engineer. The model of mechanical bar splice to be used will be submitted to the Office of Bridge Design through the proper channels for approval. The mechanical connection will develop 125% of the specified yield strength of a Grade 60 bar. The Contractor will obtain from the manufacturer and submit to the Engineer certification indicating the mechanical bar splice is capable of developing 125% of the specified yield strength of a Grade 60 bar. The bar lengths shown in the plans are the lengths of the bars neglecting the mechanical bar splice. When mechanical bar splices are used to splice epoxy coated bars, the mechanical bar splices will be epoxy coated by the manufacturer or made of an approved corrosion resistant material. Coating the mechanical bar splice with epoxy touch-up is not an approved method for this situation.
480.4METHOD OF MEASUREMENT
Reinforcing Steel will be measured by the pound, based on the theoretical weight complete in place. The weights calculated will be based upon the following table: Bar Designation Size #3 #4 #5 #6 #7 #8 #9 #10 #11 #14 #18 Weight (pounds/foot) 0.376 0.668 1.043 1.502 2.044 2.670 3.400 4.303 5.313 7.65 13.60 Allowance will not be made for the clips, wire, or other fastening devices for holding the steel in place. 480 Page 359Mechanical rebar splices will be measured on a per each basis.
480.5BASIS OF PAYMENT
Reinforcing steel will be paid for at the contract unit price per pound. All costs involved with supplying and installing mechanical bar splices will be included in the contract unit price bid for the respective size of rebar splice as specified in the plans. Payment will be full compensation for furnishing materials, labor, equipment, and all incidentals necessary to complete the work. 491 Page 360491 BRIDGE DECK POLYMER CHIP SEAL
491.1DESCRIPTION
This work consists of preparation of the plans specified existing bridge deck surface and furnishing and placing two coats of a polymer chip seal on the prepared bridge deck surface.
491.2MATERIALS
Materials will conform to the following Sections: A.Concrete Patching Material, Bridge Deck: Concrete patching material will be packaged, dry, rapid-hardening cementitious mortar or concrete materials conforming to the requirements of ASTM C 928, Type R-3 and will contain a bonding agent and will not contain any chlorides, magnesium, or phosphates. B.Water: Section 790 C.Polymer: Section 805 D.Cover Aggregate: Section 805
491.3CONSTRUCTION REQUIREMENTS
A.Surface Preparation 1.Removal and Replacement of Loose and Delaminated Concrete: a.Concrete Removal Classification: Concrete removal will be divided into one of the following two classes: 1)Concrete Removal, Class A: Concrete removal, Class A will consist of the removal of delaminated and visibly loose concrete and any bituminous patches (when present) from the top of existing bridge deck down to a depth no deeper than the top of the top bar in the top mat of bridge deck reinforcing steel. Unintentional concrete removal below the top of the top bar in the top mat of bridge deck reinforcing steel during the concrete removal, Class A process will be considered a part of concrete removal, Class A. 2)Concrete Removal, Class B: Concrete removal, Class B areas will be determined by the Engineer after completion of the concrete removal, Class A has been accomplished. Concrete removal, Class B will consist of the removal of delaminated and visibly loose concrete that exists below the bottom limits of the concrete removal, Class A (below the top of the top bar in the top mat of bridge deck reinforcing steel). b.Concrete Removal: Concrete removal will be accomplished by jackhammers and chipping hammers, or other methods as approved by the Engineer. Jackhammers and chipping hammers will be used as follows: