随着浅部煤炭资源逐渐枯竭，深部开采已然成为常态。开采环境下，地温、地应力以及瓦斯压力是影响煤岩力学性质的重要因素，这些因素影响下的煤岩非线性力学行为也是深部开采过程中的关键基础问题。因此，本文从试验出发，基于正交试验原理，设计并开展了温度–围压–瓦斯压力作用下的煤岩力学试验。基于统计学原理，研究分析了温度、围压、瓦斯压力对煤岩力学性质的影响，结果表明：温度和围压对弹性模量、峰值应力和泊松比影响的显著性水平均为95%，瓦斯压力对弹性模量、峰值应力影响的显著性水平为95%，对泊松比影响的显著性水平为90%；同时发现，煤岩强度、弹性模量、泊松比随温度、围压和瓦斯压力的变化符合线性规律。进而，以有限变形理论为基础，结合试验条件，建立了煤岩非线性变形描述指标—平均整旋角，计算分析了其在煤岩变形破坏过程中的演化规律：平均整旋角随应力应变的变化基本可以划分为快速增长区、平缓增长区和加速增长区，这三区的出现也是煤岩压密、弹性、屈服破坏三阶段内在力学过程体现；切线模量随平均整旋角可以分为增长阶段和跌落阶段，反映了煤岩从压密、硬化到脆塑性转化的过程。最后将平均整旋角作为内变量，同时考虑温度、围压以及瓦斯压力的作用，建立了有限变形框架下煤岩大变形本构方程，通过与试验数据对比可知，本文提出的模型可以较好地描述煤岩变形破坏的全过程。

Deep mining is imperative due to the exhaustion of the shallow coal resources. Temperature, in situ stress and gas pressure are the factors that have great effects on the mechanical properties of the coal. Meanwhile, the nonlinear behavior of the coal under such environment is the key and basic task of deep mining. Therefore, based on the orthogonal experiment principles, the temperature-confining pressure-gas pressure coupled mechanical test of the coal is designed and carried out. The effects of the mentioned three factors are investigated.The results show that temperature, confining pressure and the gas pressure perform the significant effects on the elastic modulus and the peak stress, the significant level of each factor is greater than 95%. The significance level of the effects on the Poisson’s ratio induced by the temperature and the confining pressure is above 95%. The significance level of the effect on the Poisson’s ration induced by the gas pressure is about 90%. The evolution of peak stress, elastic modulus and Poisson's ratio with the three factors can be described by linear models. Furthermore, the mean rotation angle, which can be employed to describe the nonlinear deformation of the coal, is calculated and studied based on the finite deformation theory and the experimental data. The evolution of the mean rotation angle with stress and stain can be divided into three partitions, i.e. the rapid increase partition, the moderate partition and the accelerating growth partition. The three partitions can be taken for the understanding of the mechanism of the compression zone, the linear deformation zone and the yield zone of the coal. The tangent modulus varies greatly with the mean rotation angle and with an increase zone and a decrease zone, which may reflect the process of compression stage, the hardening stage and the brittle-plastic transition stage. Afterwards, the mean rotation angle is taken as an internal variable to establish the constitutive model of the coal under the effects of temperature, the confining pressure and the gas pressure. The comparison of the model and the experiment data shows that the proposed model can be used to describe the entire process of the coal deformation and failure.