岩土力学2011，Vol.32Issue(10)：2989-2997,9.
轻量砂变形及强度特性三轴试验研究
Triaxial test for deformation and strength characteristics of light weight sand
摘要
Abstract
In order to research a new type of geotechnical material--light weight sand, its deformation and strength characteristicswere researched by triaxial test. The results show that light weight sand have different primary structural strength because of different mixed ratio and age, soil samples of different primary structural strength are in the state of shear dilatancy or shear contraction under different confining pressures, these lead to strain hardening, strain softening, and three corresponding pore pressure states. Deformation modulus decreases linearly with increase of EPS(expanded polystyrene beads) mixed ratio, increases linearly with increase of cement mixed ratio and age; and there is little relation between deformation modulus and confining pressure for the same mixed ratio soil samples. Triaxial compressive strength decreases according to negative exponential relation with increase of EPS mixed ratio, increases linearly with increase of cement mixed ratio, age and confining pressure. There is a threshold for cement mixed ratio. Transformation effect of soil framework has an important effect on soil strength, and that leads to strength zoning under uniaxial and triaxial compression states. When cement mixed ratio reaches to a high value, it can weaken transformation effect of soil framework of EPS beads. Combining precursors' research production, influence factors of density and uniaxial compressive strength of light weight sand are researched; then the concept of specific strength is recommended. Prescription of light weight soil-sand can be optimized by combining unit price-specific strength figure and recipe formula. Stress-strain relation transformation of light weight soil-sand is researched, uniaxial compressive strength is recommended to be metewand of primary structural strength. The relation between critical confining pressure and primary structural strength should be built according to test and mathematical statistics; these can make contribution for numerical simulation and establishment of constitutive model.关键词
轻量砂/变形模量/抗压强度/应力-应变关系转型/原生结构强度/比强Key words
light weight sand/ deformation modulus/ compression strength/ stress-strain relation transformation/ primary structural strength/ specific strength分类
建筑与水利引用本文复制引用
侯天顺,徐光黎,楼建东..轻量砂变形及强度特性三轴试验研究[J].岩土力学,2011,32(10):2989-2997,9.基金项目
国家自然科学基金资助项目(No.40572152) （No.40572152）
生物地质与环境地质教育部重点实验室开放基金资助项目(No.BGEGF200814). （No.BGEGF200814）
