基于Burgers模型的岩盐蠕变参数试验研究

针对岩盐矿地下开采结构参数的时间依赖性,开展岩盐蠕变试验。通过岩盐单轴压缩试验获得其瞬时抗压力学特性,据此设置合理的蠕变压力级别；采用单体多级加载方式进行单轴压缩蠕变试验,获得2组不同埋深岩盐蠕变变形-时间曲线,选取4元件Burgers模型对试验曲线进行拟合分析,得到试验岩盐蠕变特性表征参数。研究结果表明：岩盐单轴压缩强度具有显著的时间弱化性,长期强度小于瞬时强度的70%；Burgers模型能够合理的描述试验岩盐的蠕变变形特征,拟合的蠕变参数能够为地下盐矿采场结构参数的设计提供借鉴。

Experimental study on creep parameters of rock salt based on Burgers model

According to the time dependence of underground mining structure parameters in rock salt mine, creep test of rock salt was carried out.Through the uniaxial compression test of rock salt, its instantaneous pressure-resistance characteristics were obtained, and a reasonable creep pressure level was set accordingly.The uniaxial compression creep test was carried out by the monomer multistage loading method, and the creep deformation and time curves of rock salt in 2 groups with different buried depth were obtained.The results show that the uniaxial compression strength of rock salt has significant time weakening and the long-term strength is less than 70% of the instantaneous strength.Burgers model can reasonably describe the creep deformation characteristics of rock salt, and the fitting creep parameters can provide references for the design of underground salt mine stope structure parameters.