地质力学模型试验技术研究及工程应用

Techniques of Geomechanical Model Test and Engineering Application

针对在地质力学模型试验研究过程中存在的岩体材料相似模拟以及结构面相对位移测试问题,首先开展了不同性能岩体变形特性的相似模拟研究,试验结果确定了配制岩体模型材料的成分及其制备方法,得到了水泥、石蜡和机油是影响高、中、低性能岩体模型材料变形特性的控制性因素,提出了不同变模岩体材料采用不同尺寸的模型小块体进行精细化模拟。同时,采用应变测试技术,研制了用于获取结构面相对位移的测试仪器,测试时,用应变仪记录不同加载条件下相应测点的应变变化过程,再由埋设之前标定得到了位移和应变系数,即可得出位移变化过程。上述研究成果在小湾拱坝模型试验中的应用表明,所制备的模型材料以及结构面相对位移测试技术是满足模型试验要求的。

The objective of the present study is to tackle problems in the simulation of rock body material and the measurement of relative displacement of structural planes in geomechanical model test.Firstly,the deformation characteristics of different rock body materials was simulated,and the composition and preparation method of rock body model material were determined.It was found that the cement,paraffin and engine oil were main factors controlling the deformation characteristics of model materials of high,medium and low performances.Refined simulation using small blocks of different sizes was proposed for the rock materials with various deformation moduli.Moreover,strain test technique was employed to develop a measurement instrument for the relative displacement of structural planes.In the test,the strain changes of measurement points under different loading conditions were recorded by strain gauges,and the displacement process was obtained according to the calibrating coefficients of displacement and strain obtained before the embedment.The research findings were applied to Xiaowan arch dam model test and the results indicates that both the model material prepared in this study and the measurement technique for relative displacement of structural plane meet the requirements of model test.