ABSTRACT
The aim of the tests are to check for the bending crack bridging capability for waterproof membranes systems that have been subjected to heat during placing of hot asphalt concrete.
The waterproof membrane systems were coated on concrete prism specimens (15×15×55cm) with pre-cracks introduced on the concrete surfaces. Heat treatment was then introduced to simulate the effects of heating due to placing of hot asphalt concrete. The amount of heat energy measured from the asphalt concrete paving tests were applied here. Based on the thermal hysteresis results, heat energy of 100° C×100min. was applied to the test specimens. The test method was based on the procedure specified by Hanshin Expressway Public Corporation(2)(Japan). In order to visually inspect for cracks occurring in the waterproof membrane system throughout the tests, the surface where the layer of waterproof membrane was coated was set facing upwards, with the tensile region being on the top surface. The specimens were subjected to loading at three points (center loading). Crack formation in the waterproof membrane system and also its progression was monitored with the help of crack gauges placed across the cracks in the concrete specimen, while the midspan deflection was measured using electronic deflection meters and the load was measured using a load cell. Formation of cavities or cracks on the waterproof membrane were checked through visual inspection.
