千枚岩相似材料研制及模型试验初步应用

千枚岩是一种物理特性较差的软岩,对隧道工程影响较大,而目前关于千枚岩流-固耦合相似材料的研究较少。以砂、铁粉为骨料,水泥、石膏为胶结剂,橡胶粉为外加剂研制千枚岩流-固耦合相似材料,通过对相似材料的密度ρ、弹性模量E、粘聚力c、内摩擦角φ、渗透系数K、孔隙率ω和软化系数K_P进行测定,分析各因素对材料参数的敏感度与显著度,得出可用于试验配比的多元回归方程,并将其应用在基于沙湾隧道为工程背景的模型试验中,对模型试验洞周位移变化规律进行分析。研究结果表明:橡胶粉掺量对密度ρ的影响较显著,骨胶比对弹性模量E、粘聚力c、渗透系数K的影响较显著,水膏比对内摩擦角φ的影响显著,砂粒径对软化系数K_P的影响显著,骨胶比、砂铁比、橡胶粉掺量三个影响因素对孔隙率ω的影响都较显著。基于试验配比的线性多元回归方程能为千枚岩相似材料的研制提供帮助。

Preliminary Application of Similar Materials Development and Model Test of Phyllite

Phyllite are soft rocks with poor physical properties, which have a great impact on tunnel engineering. At present, there are few studies on similar materials for flow-solid coupling of phyllite. Sand and iron powder are used as aggregate, cement and gypsum are cementing agents, rubber powder is used as admixture to develop ternary fluid-solid coupling similar materials, through density, elastic modulus, cohesion force and internal friction angle of similar materials. The permeability coefficient, porosity and softening coefficient were measured. The sensitivity and significance of each factor to the material parameters were analyzed. The multivariate regression equations that can be used for the test ratio were obtained and applied to the model test based on the Shawan Tunnel. In the model test, the variation law of the displacement of the hole around the model is analyzed. The results show that the effect of rubber powder dosage on density is significant. The effect of bone rubber ratio on elastic modulus, cohesion and permeability coefficient is significant. The effect of water paste on internal friction angle is significant. The effect is significant. The three influencing factors of bone-binder ratio, sand-iron ratio and rubber powder content have significant effects on porosity. The linear multiple regression equation based on the test ratio can help the development of phyllite similar materials.