高应力软岩流变特性及预应力锚固技术分析

随着中国煤矿开采深度的不断增加，高应力软岩巷道支护已成为制约煤矿安全生产的主要瓶颈.依据软岩三轴压缩的分级加载蠕变试验曲线的规律与时效特征，建立了高应力下泥质粉砂岩Burgers粘弹性流变模型，并依据粘弹塑性力学的基本理论，推导了该模型的一维蠕变本构方程，进而借助非线性回归分析辨识了模型参数.采用FLAC3D软件数值模拟预应力锚杆与锚索预紧力对高应力软岩巷道蠕变的影响，仿真结果表明，随着锚杆与锚索预紧力的提高，巷道围岩的位移量逐渐减小，锚杆预紧力大于100 kN且锚索预紧力大于900 kN较为合理.

Rheological Property and Pre-Stressed AnchorageTechnology of High Stress Soft Rock

With increasing depth of coal mining,roadway support problems in high-stress soft rock have become increasingly prominent.The supporting of soft rock roadway stability has become a major bottleneck for coal mine production safety.According to the curve  law and time-dependent properties,obtained by the soft rock graduation loading triaxial compression creep test,Burgers viscoelasticity rheologic model of argillaceous siltstone at high-stress situation was established.On the basis of viscoelastic plasticity mechanics theory,the one-dimensional creep constitutive equation of this model was derived,and then the model parameters were identified with the help of non-line regression.The imparts of  the pre-tension of bolts and cables on the creep of the high stress soft rock roadway was analyzed by FLAC3D.The results showed  that the creep of the high stress soft rock roadway  reduced when the pre-tension of bolts and cables increased,and the pre-tension of bolts and cables must exceed 100 kN and 900 kN.