A New Test Method And Influence Factors For Low-temperature Adhesive Performance Of Crack Sealant

Using crack sealant to seal the cracks is the most common way to maintain the cracks. It can prevent the water and other things into the cracks, prevent the pavement from problems such as potholes or base failure. But in the area with large temperature range, crack sealant is easily in failure after a short period since the installation.There are two common types of crack sealant failure: the adhesive failure and the cohesive failure. And the adhesive failure is the most common failure of crack sealant. But there is no effective evaluation methodology for low-temperature adhesive performance for crack sealant. This paper studies the adhesive performance of crack sealant in the cold environment, presents a test method for the low-temperature adhesive performance of crack sealant and studies the influence factors of adhesive performance. The main substance of this paper as follows:This paper works on a new investigation on the failure rate of crack sealant. And this paper presents a new evaluation methodology of sealant failure rate based on methodologies which already exit. It shows that the failure rate of crack sealant in Heilongjiang Province is as high as70%.This paper presents a text method based on an existing low-temperature performance testing device of crack sealant. And this paper studies the low-temperature adhesive performance of crack sealant by changing the size of the sealant, the test temperature and the velocity of the test. Based on the tests, a standard text method is presented.The surface of asphalt concrete block which is design to bond with the sealant is analyzed and studies the influence of the area of aggregate, asphalt mortar and void of the bonding surface on the low-temperature adhesive performance of crack sealant. In order to simulate the environment that the sealant work in, natural silica sand is mixed into crack sealant to study the influence of aggregate into sealant on its performance. It shows that the area of asphalt mortar has a positive correlation with low-temperature adhesive performance, the area of aggregate has a negative correlation with adhesive performance, the area of void has a complex influence on the adhesive performance of crack sealant with the bonding surface. 5different kinds of crack sealant are tested using the method this paper presented and tested using ductility test, rotational viscometer, BBR, DSC and DSR The relationship between the test results and the results of low-temperature performance is discussed. It shows that the low-temperature performance using other test methods has an acceptability correlation with adhesive performance of crack sealant and there is special kind of crack sealant exiting which has good low-temperature performance but has poor adhesive performance. Some advices are given to improve the low-temperature performance for the crack sealant based on the results of field investigation and indoor texts.