动力学相似材料配比试验研究

地质力学模型试验是一种形象、直观的岩体物理力学性质研究方法, 被广泛地应用于国内外岩土工程界。在地质力学模型试验中, 如何快速、准确地选择材料的配比是成功模拟原型的关键。随着动力学模型在地质力学模型试验中的应用越来越广泛, 对相似材料配比的研究也应从静力学方法向动力学方法转变。相似材料由骨料与胶结物混合而成, 两者的含量变化是影响相似材料性质的重要参数。本文选择以河砂为骨料, 石膏和水泥为胶结物, 采用弹性波速测量和单轴抗压试验的方法, 研究了不同配比条件下材料的物理、力学性质的变化规律。实验结果表明:单独以水泥或石膏作为胶结物时, 在骨料与胶结物总量不变的情况下, 试件的质量及动、静弹性模量随砂胶比的增大呈先增大后减小的变化; 以水泥和石膏混合作为胶结物时, 在砂胶比与胶结物总量不变的情况, 试件的动、静弹性模量随石膏和水泥用量比的增加呈先减小后增大的变化。

THE APPLICATION OF ELASTIC WAVE TEST METHOD IN SIMILAR MATERIAL EXPERIMENTS

Geotechnical model featured by vivid and visualized research method of rock physical and mechanical property is widely used in the field of geotechnical engineering both at home and abroad. In geotechnical model tests, the speed of accuracy of material ration selection plays a pivotal part to the success of the prototype. With the wider spread application of dynamical model in geotechnical model experience, the study of similar material ratio also converts its direction from statics to dynamics. Similar material is the mixture of aggregate and cement, and the change of their ratio exerts a great influence on the property of similar material selecting river sand as the aggregate, cement and plaster as the cementing agent. This paper studies the physics and mechanical property under different ratio conditions by the elastic wave speed simulation measurement and uniaxial compressive test. Experimental results show that on the condition that the cement or plaster alone serves as cementing agent and the amount of aggregate and cement remains constant, the mass, dynamic and static elasticity modulus of the specimen will climb up and then decline with the increase of sand-binder ratio, while when the mixture of cement and plaster serve as cementing agent and the amount of cementing agent and sand-binder ratio remain constant, the dynamic and static elasticity modulus of the specimen will decline followed by a climb with an increase of cement and plaster-use ration.