加载速率与环境温度对黏土岩力学性质的影响

On the influence of loading rate and ambient temperature on the mechanics properties of clay rock

利用SHT4305伺服压力机系统．对黏土岩试样分别在0．1MPa／s、O．3MPa／S、0．5MPa／s、0．7MPa／’s、0．9MPa／s的加载速率和25C、55C、85C、115C、¨5C的环境温度下实施单轴压缩试验．分析了不同加载速率和不同环境温度对黏土岩的峰值强度、弹性模量、应变状态、破裂形式、反应过程以及变化机制的影响。研究发现，黏土岩试样在不同加载速率和环境温度作用下．破坏过程经历压密、弹性、塑性、破坏四个阶段，其中塑性阶段差异化明显。黏土岩峰值强度与加载速率近似线性相关；在环境温度的作用下，黏土岩峰值强度与弹性模量随温度的增加呈现出先增大后减小的趋势。上述研究结果对高放核废物处置库选址等领域备选具有重要的理论意义和参考价值。

By using SHT4305 hydraulic servo press system, uniaxial compression experiment was carried out for clay rock samples at loading rate of 0.1MPa/s, 0.3MPa/s, 0.5MPa/s, 0.7MPa/s and 0. gMPa/s and at different temperature of 25℃, 55℃, 85℃, 115℃ and 145℃, respectively. The peak strength, and elastic modulus, strain state, rupture form, reaction process and variation mechanism of clay rock samples at different loading rates and ambient temperatures were analyzed. Results shows that the failure process of clay rock samples at different loading rates and at different ambient temperature experiences four stages： compaction, elasticity, plasticity and destruction, in which the plasticity stage is is obviously different. Peak strength of clay rock is approximately linearly correlated with the loading rate. Under the action of ambient temperature, the peak strength and elastic modulus of clay rock increase first and then decrease with the increase of temperature. Above results may have important theoretical significance and reference value for the selection of high-level radioactive nuclear waste disposal sites.