【摘要】 研究目的:透明砂土是利用熔融石英砂和具有相同折射率的孔隙液体配置的新型岩土工程材料。为深人了解其力学特性,本文采用三轴仪对粒径为0. 5～1.0 mm和1.0～3. 0 mm的熔融石英砂进行CU和CD试验,对比分析二者的应力应变、孔压、有效应力比等参数变化规律,并且通过试验分别计算得到粗砂和细砂的E-μ模型参数,为开展数值计算提供相应参数。研究结论:(1)松散的透明砂土试样应力应变曲线表现出硬化特性;(2)粗粒径试样应力应变曲线陡峭,达到峰值的速率较细粒径试样快;(3)固结不排水剪切试验粗粒径试样孔压值大于细粒径的孔压值,二者的孔隙水压力系数A_f随着围压的增大而呈减小趋势;(4)可以用透明砂土模拟天然土体,不同粒径的透明砂土可以表征不同土体;(5)该研究成果可为基于透明土技术的模型试验研究提供参考。更多还原

【Abstract】 Research purposes : Transparent sand is a new type of geotechnical engineering material, which is made of fused silica sand and porous liquid with the same refractive index. In order to understand its mechanical properties, the CU and CD tests of fused silica sand with a particle size of 0.5～1. 0 mm and 1.0～3. 0 mm are carried out by triaxial apparatus, and the stress-strain curves,pore water pressure changes and effective stress ratio of the two are compared and analyzed. In addition, E-μ model parameters of coarse and fine sand are calculated respectively, which provide corresponding parameters for further numerical calculations.Research conclusions:(1) The loose samplers stress-strain curve shows hardening characteristics.(2) The coarse particle specimen with steeper stress-strain curve comes to the peak at faster velocity than fine particle specimen.(3)The pore pressure value of the coarse particle specimen is greater than the fine particle, the pore water pressure coefficient of the two shows a decreasing trend with the increase of the confining pressure.(4) Transparent sand can be used to simulate natural sand and the change of diameter can represent different soils.(5) The research results can provide reference for model tests based on transparent soil technique.更多还原