为了研究西部地区白垩系富水软砂岩地层中采用冻结法施工时发生的流变破坏问题，依托国家自然科学基金（51774231）以陕西彬长孟村和甘肃新庄冻结立井工程为背景，围绕影响冻结软砂岩流变特性的几个重要因素如：冻结温度、岩层的含水状态、冻结井筒或巷道的围压等，对典型的白垩系红色砂岩进行常规力学试验和蠕变力学试验及其他基本物理参数试验，探究白垩系软砂岩冻结蠕变力学特性，并建立使用与白垩系冻结软砂岩的蠕变本构模型，为西北地区矿井建设提供指导。经研究分析得出以下主要结论： （1）通过X-射线衍射矿物组成分析，得出红色砂岩主要是石英和长石矿物，伴随小部分黏土矿物，通过电子显微镜放大拍照，观察出红色砂岩是大颗粒胶结而成充填有黏土矿物，且内部含有小裂隙，大孔隙多，结构松散。 （2）红色砂岩峰值强度随着饱和度的增加而呈指数降低，大部分强度损失在40%饱和度以下，砂岩的峰值轴向应变，随着饱和度增加而增加，并且在80%饱和度以应变增加最多。红色砂岩长期强度随饱和度呈指数增加，且长期强度为极限强度的60%～70%左右；红色砂岩蠕变量随饱和度增加呈线性增大趋势，红色砂岩遇水软化明显。 （3）白垩系软砂岩的强度随着温度的降低呈近似二次曲线增加，泊松比和弹性模量随着温度降低而增加；峰值强度随着围压增加而增加，同时峰值点应变随着围压增加呈线性增加；软砂岩在常温下明显存在孔隙加密阶段，在低温下此阶段不明显。 （4）红色砂岩长期强度随着温度降低而增加，且长期强度对应的应力水平也提高，6MPa围压下红色砂岩-20℃时长期强度的应力水平比室温下提高了20%，红色砂岩的变形量随着温度降低而降低。 （5）红色砂岩长期强度对应的应力水平随围压的增加而增加，围压从0MPa到2MPa时变化较为明显；红色砂岩的变形量随着围压的增加而降低，表明围压的横向约束对岩石的变形有着约束作用；破坏后，红色砂岩剪切角随着围压增加而增加。 （6）通过对已有的软岩流变理论总结发现，软岩蠕变特性影响因素主要包括应力水平、围压、温度、含水率、冻融作用、化学腐蚀作用、干湿循环作用、渗流作用等；结合试验数据分析建立了改良凯尔文体的损伤蠕变本构模型，通过试验数据的拟合验证，证明该本构模型对加速蠕变阶段的蠕变曲线能够很好的优化。

In order to study the rheological damage caused by the freezing method in the Cretaceous water-rich soft sandstone strata in the western region, several important factors affecting the rheological properties of the frozen soft sandstone are: freezing temperature, water condition of the rock formation, freezing the wellbore or Confining pressure of roadway, etc., relying on the National Natural Science Foundation of China (51774231) to carry out conventional mechanical tests and creep mechanics tests and other basic physical parameters of typical Cretaceous red sandstones in the background of Shaanxi Binchang Mengcun and Gansu Xinzhuang freezing shaft project. Experiments were conducted to investigate the freezing creep mechanical properties of the Cretaceous soft sandstone, and to establish a creep constitutive model using the Cretaceous frozen soft sandstone to provide guidance for the construction of the mine in the Northwest. After research and analysis, the following main conclusions are drawn: (1)By X-ray diffraction mineral composition analysis, it is concluded that the red sandstone is mainly quartz and feldspar minerals, accompanied by a small part of clay minerals, and magnified by electron microscopy, it is seen that the red sandstone is a large particle cemented and filled with clay minerals. And the interior contains small cracks, large pores and loose structure. (2)The peak intensity of red sandstone decreases exponentially with the increase of saturation, most of the strength loss is below 40% saturation, and the peak axial strain of sandstone increases with the increase of saturation, and at 80% saturation. Increase the strain by the most. The long-term strength of red sandstone increases exponentially with saturation, and the long-term strength ultimate strength is about 60%-70%; the red sandstone creep variable increases linearly with saturation, and the red sandstone softens with water. (3)The strength of the Cretaceous soft sandstone increases with the decrease of temperature, and the Poisson's ratio and elastic modulus increase with the decrease of temperature; the peak intensity increases with the increase of confining pressure, and the peak point strain increases with The increase of confining pressure increases linearly; soft sandstone obviously has pore encryption stage at normal temperature, and skips this stage directly at low temperature. (4)The long-term strength of red sandstone increases with the decrease of temperature, and the stress level corresponding to long-term strength also increases. The stress level of long-term strength of red sandstone at 20 °C under 6 MPa confining pressure is 20% higher than that at room temperature. Red sandstone The amount of deformation decreases as the temperature decreases. (5) The stress level corresponding to the long-term strength of red sandstone increases with the increase of confining pressure, and the change of confining pressure from 0MPa to 2MPa is the most obvious; the deformation of red sandstone decreases with the increase of confining pressure, indicating the lateral constraint of confining pressure. The deformation of the rock has a constraining effect; after the failure, the shear angle of the red sandstone increases as the confining pressure increases. (6) Through the summary of soft rock rheological theory, the influencing factors of soft rock creep characteristics mainly include: stress level, confining pressure, temperature, water content, freeze-thaw action, chemical corrosion, dry-wet cycle, seepage The damage constitutive model of the modified Kyle body is established by combining the experimental data analysis. The fitting data of the constitutive model can be optimized for the creep curve of the accelerated creep stage.