Concrete Joint Materials
408.1 Description
This item shall govern for the furnishing and placing of all longitudinal, contraction and expansion joint material in concrete work as herein specified in the various items of these specifications as indicated or as directed by the Engineer.
408.2 Materials
(1) Preformed Asphalt Board
Preformed asphalt board formed from cane or other suitable fibers of a cellular nature securely bound together and uniformly impregnated with a suitable asphaltic binder and meeting the requirements of the Standard Specifications for Preformed Expansion Joint Filler for Concrete Paving and Structural Construction, ASTM D 1751.
(2) Preformed Nonbituminous Fiber Material
Preformed nonbituminous fiber material shall meet the requirements of the Standard Specifications for the Preformed Expansion Joint Filler for Concrete Paving and Structural Construction, ASTM D 1751, except that the requirements pertaining to bitumen content, density and water absorption shall be voided.
(3) Boards
Boards obtained from Redwood timber, of sound heartwood, free from sapwood, knots, clustered birdseye, checks and splits. Occasional sound or hollow birdseye, when not in clusters, will be permitted provided the board is free from any other defects that will impair its usefulness as a joint filler.
(4) Joint Sealer (Concrete Pavement)
This material shall be a one part low modulus silicone especially designed to cure at ambient temperatures by reacting with moisture in the air and shall have the following properties:
As Supplied |
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Color |
Gray |
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Flow, MIL-2-8802D Sec. 4.8.4 |
0.2 maximum |
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Working Time, minutes |
10 |
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Tack-Free Time at 77 F± 2F Min. MIL-2-8802D Sec.4.8.7 |
60 |
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Cure time, at 77F (25C), days |
7-14 |
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Full Adhesion, days |
14-21 |
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As Cured---after 7 days at 77 F (25C) and 40% RH |
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Elongation, percent minimum |
1200 |
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Durometer Hardness, Shore A, points ASTM 2240 |
15 |
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Joint Movement Capability, percent |
+100/-50 |
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Tensile Strength, maximum elongation, psi |
100 |
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Peel Strength, psi |
25 |
The joint sealer shall adhere to the sides of the concrete joint or crack and shall be an effective seal against infiltration of water and incompressibles. The material shall not crack or break when exposed to low temperature.
(5) Backer Rod
Backer Rod shall be expanded closed cell polyethylene foam compatible with sealant. No bond or reaction shall occur between rod and sealant. Backer Rod shall be of sufficient width to be in compression after placement and shall be used with joint sealer.
(6) Joint Sealing Material
Joint Sealing Material for other than pavement use may be a two-component, synthetic polymer or cold-pourable, self leveling type meeting the following requirements:
The material shall adhere to the sides of the concrete joint or crack and shall form an effective seal against infiltration of water and incompressibles. The material shall not crack or break when exposed to low temperatures. Curing is to be by polymerization and not by evaporation of solvent or fluxing of harder particles. It shall cure sufficiently at an average temperature of 77±3F so as not to pick up under wheels of traffic in a maximum of 3 hours.
Performance Requirements:
When tested in accordance with Test Method Tex-525-C, the joint sealing material shall meet the above curing times and the requirements as follows:
It shall be of such consistency that it can be mixed and poured or mixed and extruded into joints at temperatures above 60 F.
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Penetration 77F., 150 gm. Cone, 5 sec., max.-cm |
0.90 |
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Bond and Extension 75%, 0F, 5 cycles: Dry Concrete Blocks |
Pass |
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Wet Concrete Blocks |
Pass |
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Steel Blocks (Primed if specified by manufacturer) |
Pass |
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Flow at 200 F |
None |
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Water content % by weight, max. |
5.0 |
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Resilience: |
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Original sample min. % (cured) |
50 |
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Oven-aged at 158 F. min. % |
50 |
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For Class 1-a material only, Cold Flow (10 minute) |
None |
408.3 Construction Methods
The Contractor shall install "Concrete Joint Materials" which will function as a compatible system. Joint sealer shall not be placed where a bond braker is present.
Asphalt, Redwood board or other materials used shall extend the full depth of the concrete and shall be perpendicular to the exposed face. All joints shall be shaped to conform to the contour of the finished section in which they are installed. All material shall be a minimum of 1/2 inch thick or as indicated. Wood materials shall be anchored to the adjacent concrete to permanently hold them in place. Joint sealer shall be installed in accordance with the manufacturer's recommendations.
The material used for side walk expansion joints shall conform to No. 3 above, unless otherwise indicated.
The material used for curb and gutter expansion joints filler shall conform to any of the above, except when placed adjacent to concrete pavement, the joint material shall match the pavement joint material.
408.4 Measurement and Payment
No direct measurement or payment will be made for the work to be done or the equipment to be furnished under this item, but shall be considered subsidiary to the particular items required by the bid.