Research on the Crack Resistance at Low Temperature and the Mechanism of Semi-Flexible Pavement

Abstract

Abstract-The crack resistance at low temperature of semi-flexible pavement was favorable, which prepared by waterborne epoxy-emulsified asphalt-cement as grouting material. While the E/A is 0.6, the maximum bending strain has reached 2662με, which is close to SMA-13. In the three-phase grouting system, asphalt was continuous phase, waterborne epoxy was dispersed phase, both of them bonded with cement. Keywords-semi-flexible pavement;the crack resistance at low temperature; waterborne epoxy; compound grouting system Cement pavement has the advantages of high strength, large bearing capacity and small temperature sensitivity, while its shortcomings are not comfortable drying and difficult repairing. Because of the advantages of excellent function and convenient repairing, asphalt pavement has become the mainstream of the development of the highway. However, our country has a vast territory and complicated climate characteristics, along with the canalized traffic, the disadvantages of poor bearing capacity, big temperature sensitivity and poor water stability have been the main factors to damage [1][2][3][4] . Based on this background, semi-flexible pavement was appeared, which has both the advantages of cement pavement and asphalt pavement. Semi-flexible pavement is based on framework void asphalt mixture and filled with cement mortar [5][6] . The study generally indicated that semi flexible is a kind of price and good performance of pavement, but the current application indicate that semi flexible materials is easy to appear cracking damage. The main reason is the interface bonding force between cement and asphalt is only Van Edward force, which can't resist the internal stress by the shrinkage of cement and the thermal expansion of asphalt [7] . The most study on the modified measure of semi-flexible did not have the ideal effect. Using the high bonding force of waterborne epoxy and the flexibility of emulsified asphalt, the study has prepared the high performance semi-flexible material and researched its crack resistance at low temperature.