基于正交设计的岩石相似材料配比研究及底摩擦物理模型试验应用

Investigation of the rock similar material proportion based on orthogonal design and its application in base friction physical model tests

在铁精砂胶材料基础上,加入黏土作为增塑剂,应用正交设计法,以黏土/(骨料+黏土)、(铁粉+重晶石粉)/骨料、铁粉/(铁粉+重晶石粉)及石膏/混合料为4个因素,每个因素设置5个水平,共25组材料配比方案,开展相关试验测定了各组材料的密度、抗压强度、抗拉强度、弹性模量、泊松比、内摩擦角及黏聚力等参数指标,并研究了参数与影响因素之间的变化规律。基于上述分析,配制了两种不同岩石相似材料,并开展了相关底摩擦模型试验。研究结果表明:(1)根据配比方案所配制的相似材料物理力学参数分布范围广,可满足不同岩性相似材料的配制需求;(2)各个因素对相似材料物理力学参数影响效果规律性强,便于通过调节配比模拟不同岩石材料;(3)应用配比方案对两种岩性差异较大的岩石相似材料进行配制,其物理力学参数与原岩具有较高的吻合度;(4)基于所配相似材料开展的反倾边坡底摩擦模型试验具有很好的试验效果。

On the basis of iron barites sand cementation material,clay was added as the plasticizer and the weight ratio of clay to aggregates plus clay,the weight ratio of iron ore powder plus barite powder to aggregates,the weight ratio of iron ore powder to iron ore powder plus barite powder,and the weight ratio of gypsum to mixture were selected as four factors with five variable levels.Twenty five schemes of the material mixture ratio were designed using orthogonal design method,and related laboratory tests were conducted to obtain physical and mechanical parameters of similar materials such as density,compressive strength,tensile strength,elastic modulus,Poisson’s ratio,internal friction angle and cohesion.Moreover,variations in concerned parameters were analyzed for different material mixture ratios.Based on the analysis above,similar materials of two different real rocks were prepared and two related base friction physical model tests were also carried out.The test results reveal that,1)the physical and mechanical parameters of the similar materials fabricated according to the similarity ratio proposed in this study vary considerably,which can satisfy the requirement of different kinds of rocks;2)the influence of each factor on the physical and mechanical parameters of similar material shows good regularity,which facilitates identifications of the optimum mixture ratios for different rock materials;3)the physical and mechanical parameters of two different materials are consistent with those of the real rocks to a great extent;4)these two different rock similar materials can be successfully applied in the base friction physical model tests.