Cohesive property evaluation of crack sealants using a low-temperature tensile tester

This paper presents a new test method that was developed to evaluate the cohesive properties of crack sealants at low temperatures. The low-temperature tensile tester (LTTT) used in this test method was self-developed as a result of field-investigation experiences. Field investigations of crack expansion were conducted in four climate regions in Heilongjiang Province, China, to understand the actual working environment. The LTTT, highly efficient and equipped with a wide measurement range, was then developed. The cohesive specimen is dog-bone shaped and 24 × 24 mm in width and thickness, a size selected based on the test results of various specimen dimensions. The optimal elongation rate was 100 mm/h, and displacement-at-failure emerged as the evaluation index, having been derived from the analysis of test results at various temperatures and elongation rates. According to the results of field investigation, the threshold values of displacement-at-failure were 84, 60, 36, and 28.8 mm, from the lowest to the highest temperature region. The cohesive properties of six types of sealant were assessed on the threshold-evaluation values of the various regions. This test method can effectively differentiate the cohesive properties of various sealants and can be applied in a diversity of climate regions.