基于全尾砂充填体非线性本构模型的深井充填强度指标

目前矿山深井充填体强度指标是类比浅部充填经验来确定的,为改变这种不合理局面,根据某深井开采矿山全尾砂充填体单轴压缩实验的应力-应变关系曲线,建立了全尾砂充填体峰值应力前的非线性本构模型.结合全尾砂充填体与深部围岩耦合作用下能量损耗相近的原则,得出了全尾砂充填体抗压强度设计公式.实例研究结果表明:建立的全尾砂充填体峰值应力前的非线性本构模型与实验结果吻合;深部开采全尾砂充填体强度指标与围岩原岩应力、弹性模量以及充填体本身的力学性能有关,采用非线性本构模型确定的全尾砂充填体强度指标比采用线性本构模型确定的强度指标更精确.

Strength Determination of Crude Tailings Backfill in Deep Mine Based on Non-linear Constitutive Model

Backfill strength in deep mining is commonly determined by analogy with shallow mining experience at present. In order to change this unreasonable situation， non-linear constitutive models of crude tailing backfills (CTBs) before peak strength were constructed based on uniaxial compression experimental results of CTBs in a deep mine， and the equation of necessary compressive strength was consequently derived based on the principle that there is approximate energy loss within a backfill and surrounding rock compound system. It is proved by a case study that the non-linear constitutive model of CTB before peak strength is identical to the experimental result and that the CTB strength in deep mining is related not only to the mechanical performance of the CTB itself， but also to the in-situ stress and elastic modulus of surrounding rock. The case study also suggests that the calculated necessary backfill strength by the non-linear constitutive model is more accurate than that by the linear constitutive model.