Study on Mechanical Properties of Cement Cold Recycling Mixtures in Seasonally Frozen Soil Region

Abstract

In order to analyze the influences that cement has on the mechanical properties of asphalt cold recycling mixtures in seasonally frozen soil region, taking asphalt pavement milling recycling material of different gradation as a benchmark, by proposing the indoor experiments, studying the mechanical properties of cement cold recycling mixtures (CCRM) that have different amount of cement content. The results show that the unconfined compressive strength, splitting strength and compression rebound modulus of CCRM increase in non-linear mode with the growth of curing period, the curve increases faster in the early stage, then the growth rate decreases gradually, and tends to zero finally. The proportion of base and surface has great influences on mechanical properties of CCRM, when the proportion of base and surface is 12:5, the compressive strength is 2.5~3.2MPa, the splitting strength is 0.38~0.52MPa, the compressive modulus is 1013~1206MPa. The cement content and curing period are the key factors affecting the mechanical properties of CCRM, the strength and modulus magnify with cement content and curing period increasing, and finally tend to the limit value. There is a good linear relationship between unconfined compressive strength and splitting strength and between unconfined compressive strength and compression rebound modulus.