Laboratory shear bond test for chip-seal under varying environmental and material conditions

Ideally, a complete bond between the chip-seal and asphalt pavement is achieved during the chip-seal application. However, complete and total bonding is unlikely due to environmental and material conditions. Therefore, it is critical to understand the bond qualities under varying environmental and material conditions, which is also beneficial for cleaner production of chip-seal applications. The shear bond strength is a crucial indicator for revealing the bond qualities of chip-seal with asphalt pavement. The objective of this study is to develop a laboratory approach to characterise the shear bond strength of a chip-seal application with the asphalt pavement. It is achieved by developing a laboratory approach to the shear bond test (SBT). This study investigated the shear bond strength between chip-seal and asphalt pavement of several asphalt-aggregate combinations and different asphalt-emulsion application rates. Also, in order to characterise the influence of temperatures and freeze-thaw cycles on the durability of chip-seal, several test temperatures, and the multiple freeze-thaw cycles were applied in the proposed SBT. The laboratory test outcomes recommended that the weak shear bonding of chip-seal with asphalt pavement is in part because of the multiple freeze-thaw cycles suffered and the raw materials used.

Automated summary

The study focused on the shear bond strength between chip-seal and asphalt pavement, and concluded through laboratory testing that the weak shear bonding is partly caused by multiple freeze-thaw cycles and the raw materials used.