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Edgewater Creek Bridge Replacement November 2023 140 conditioning at 38°C±1 for 100 hours. No cracks shall be visible 1 using 7X magnification. 2 e) Low Temperature Compression Set (ASTM D1229) at -10°C for 7 3 days: 4 Maximum permissible set = 65% 5 F. Results from tests performed on each batch of elastomer used in the 6 isolators shall demonstrate compliance with the following requirements: 7 a) Tensile Strength (ASTM D412) 8 Minimum permissible tensile strength = 2200 psi 9 b) Elongation at break (ASTM D412) 10 Minimum permissible elongation at break = 500% 11 c) Shear Modulus (ASTM D4014, Method A) 12 Measure and report secant stiffness between 25% and 75% shear 13 strain 14 15 Fabrication 16 The tolerances on isolator dimensions prior to testing shall be as follows: 17 18 External Plan Dimensions ±¼ inch Overall height ±¼ inch Variation between top and bottom surface < 0.005 radian Variation of sides from theoretical ±¼ inch Flatness of external plates ±1/16 inch per 36 inches 19 Exposed steel surfaces, if any, shall be protected from rust by one coat of 20 zinc-rich primer. Further coating by the Contractor may be required by the 21 contract documents. 22 23 Each isolator shall be marked with the isolator serial number specified by 24 the manufacturer. 25 26 Testing 27 28 Prototype Tests 29 Isolation system suppliers who have submitted characterization test results 30 by means of the evaluation findings of the Highway Innovative Technology 31 Evaluation Center shall perform prototype tests in accordance with Section 32 13.2.2 and 13.2.3; results shall be evaluated per Section 13.3 of the 33 AASHTO Guide Specification for Seismic Isolation Design. Suppliers 34 without HITEC results shall perform prototype tests in accordance with 35 Section 13 in its entirety. 36 37 Prototype test results from similar isolators may be provided in lieu of tests 38 performed on the isolators for the subject project. Tests must have been 39 performed on complete, assembled isolators. 40 41 Quality Control Tests 42 Each isolator shall be tested and evaluated in accordance with the 43 requirements of the AASHTO Guide Specifications for Seismic Isolation 44 Design, Section 15.2. Only tests on complete isolator units will be accepted. 45 Any bearing that fails to satisfy the requirements shall be rejected. 46 47