The coal seam and the roof of the roadway bear loads together in the underground engineering of coal mine. Especially for the roadway driven along the roof, its deformation is completely different from that arranged in the complete rock stratum. Accurately knowing the mechanical mechanism of coal-rock combined body can help understand the deformation and failure modes of such roadways. This article started with tests of coal-rock combined samples with different height ratios, based on the test results, a strain softening damage constitutive model of coal-rock combined body and a method for solving the parameters of the model were proposed, and the influence of the model parameters was discussed. The test results show that the stress peak value and residual strength of the coal-rock combined samples are negatively correlated with the proportion of coal in the coal-rock combined samples, and have a positive correlation with the confining pressure. The damage constitutive model fitted the test curve well. The model can accurately describe the stress-strain curve of coal-rock combined samples, and can reflect the influence of different height ratios of coal and rock samples and confining pressures. The effects of model parameters were discussed based on the damage constitutive model, which are expected to be widely used in underground engineering.

煤矿井下工程中煤层与巷道顶板共同承受荷载。尤其是沿顶板掘进的巷道，其变形与布置在完整岩层中的变形完全不同。准确了解煤岩组合体的力学机理，有助于了解此类巷道的变形破坏模式。本文从不同高度比煤岩组合试样的试验入手,根据试验结果,提出了煤岩组合体应变软化损伤本构模型及模型参数求解方法,并提出了模型参数的求解方法。讨论了模型参数。试验结果表明，煤岩组合试样的应力峰值和残余强度与煤岩组合试样中煤的比重呈负相关，与围压呈正相关。损伤本构模型与试验曲线拟合良好。该模型能够准确地描述煤岩组合样品的应力应变曲线，能够反映不同煤岩样品高度比和围压的影响。基于损伤本构模型讨论了模型参数的影响，有望在地下工程中得到广泛应用。该模型能够准确地描述煤岩组合样品的应力应变曲线，能够反映不同煤岩样品高度比和围压的影响。基于损伤本构模型讨论了模型参数的影响，有望在地下工程中得到广泛应用。该模型能够准确地描述煤岩组合样品的应力应变曲线，能够反映不同煤岩样品高度比和围压的影响。基于损伤本构模型讨论了模型参数的影响，有望在地下工程中得到广泛应用。