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• The elastomer,as determined from test specimens,shall conform to the following: <br /> ASTM <br /> Test Designation Requirement <br /> Tensile strength,MPa D 412 15.5 Min. <br /> Elongation at break,percent D 412 350 Min. <br /> Compression set,22 h at D 395(Method B) 25 Max. <br /> 70°C,percent <br /> Tear strength,kN/m D 624 ie C 31.5 Min. <br /> Hardness(Type A D 2240 with 2 k .mass 55 t5 <br /> Ozone resistance 20%strain, D 1149(except 100±20 <br /> 100 h at 40°C t2°C parts per 100 000 000) No cracks <br /> Instantaneous thermal D 1043 Shall not exceed 4 <br /> stiffening at-40°C times the stiffness <br /> measured at 23°C <br /> Low temperature brittleness D 746(Procedure B) Pass <br /> at-40°C <br /> The table in the ninth paragraph of Section 51-1.1211(1),"Plain and Fabric Reinforced Elastomeric Bearing Pads,"of the <br /> Standard Specifications is amended to read: <br /> Tensile strength,percent -15 <br /> Elongation at break,percent 40;but not less than 300%total <br /> elongation of the material <br /> Hardness points +10 <br /> The first paragraph in Section 51-1.12H(2), "Steel Reinforced Elastomeric Bearings," of the Standard Specifications is <br /> amended to read: <br /> • Steel reinforced elastomeric bearings shall conform to the requirements for steel-laminated elastomeric bearings in <br /> ASTM Designation: D 4014 and the following: <br /> A. The bearings shall consist of alternating steel laminates and internal elastomer laminates with top and bottom <br /> elastomer covers. Steel laminates shall have a nominal thickness of 1.9 mm(14 gage). Internal elastomer laminates <br /> shall have a thickness of 12 mm, and top and bottom elastomer covers shall each have a thickness of 6 mm. The <br /> combined thickness of internal elastomer laminates and top and bottom elastomer covers shall be equal to the <br /> bearing pad thickness shown on the plans. The elastomer cover to the steel laminates at the sides of the bearing <br /> shall be 3 mm. If guide pins or other devices are used to control the side cover over the steel laminates,any exposed <br /> portions of the steel laminates shall be sealed by vulcanized patching. The length,width,or diameter of the bearings <br /> shall be as shown on the plans. <br /> B. The total thickness of the bearings shall be equal to the thickness of elastomer laminates and covers plus the <br /> thickness of the steel laminates. <br /> C. Elastomer for steel reinforced elastomeric bearings shall conform to the provisions for elastomer in <br /> Section 51-1.1211(1),"Plain and Fabric Reinforced Elastomeric Bearing Pads." <br /> D. A Certificate of Compliance conforming to the provisions in Section 6-1.07, "Certificates of Compliance," shall be <br /> furnished to the Engineer certifying that the bearings to be furnished conform to all of the above provisions. The <br /> Certificate of Compliance shall be supported by a certified copy of the results of tests performed by the <br /> manufacturer on the bearings. <br /> E. One sample bearing shall be furnished to the Engineer from each lot of bearings to be furnished for the contract. <br /> Samples shall be available at least 3 weeks in advance of intended use. The sample bearing shall be one of the <br /> following: <br /> Contract No. 10-OM7104 <br /> 32 <br />