不同温度条件下砒砂岩水泥土力学特性试验研究OA

In order to explore the influence of temperature on the mechanical properties of pisha sand-stone cement soil(PSCS),unconfined compressive strength tests and GDS dynamic triaxial tests were performed on PSCS with 7％cement content under ambient temperatures of 20,0,-5,-10,and-15℃.Based on the stress-strain curves from the unconfined compressive strength test,the effect of tem-perature on the compressive strength of PSCS was analyzed from the perspective of energy absorption.Concurrently,the dynamic response characteristics of PSCS under cyclic load were studied through GDS dynamic triaxial test,focusing on the evolution law of mechanical properties and energy dissipation mechanism of the material in the temperature range of-15 ℃ to 20 ℃.The results show that the peak stress is negatively correlated with temperature.Compared with the peak stress at room temperature(20 ℃),the peak stress at 0,-5,-10,and-15 ℃ increases by 65.87％,90.46％,163.60％,and 229.38％,respectively.The peak strain displays a significant inflection near the phase transition temperature threshold(-5 ℃).The pre-crack energy,the crack energy absorbed during compression,and the post-crack energy absorbed in compression all show an increasing trend with de-creasing temperature,and the total energy absorption value at-15 ℃ increased by 515.62％compared to that at 20 ℃.Under constant amplitude cyclic loading,as the temperature decreases,the dynamic elastic modulus of PSCS progressively increases,whereas the damping ratio and cumulative plastic de-formation gradually decrease.Additionally,compared to the room temperature group under constant-amplitude cyclic loading,the average dynamic elastic modulus at 0,-5,-10,and-15 ℃ increases by 63.7％,88.1％,96.8％,and 103.0％,respectively.