压实花岗岩残积土软化特性试验研究  

Testing Study on Softening Characteristics of the Compacted Granite Residual Soil

作　　者：赖榕洲[1] 吴能森[1] 徐青[1] 

机构地区：[1]福建农林大学交通与土木工程学院,福建福州350002

出　　处：《湖北工业大学学报》2013年第5期96-98,101,共4页Journal of Hubei University of Technology

基　　金：福建省自然科学基金项目(2007J0357);福建省高等学校科技项目(JA09073);福建农林大学创新(培育)团队建设项目(Pytd12006)

摘　　要：为研究土中水对压实花岗岩残积土的软化效应,以最优含水率为基准,在等压实度条件下,制作了3组不同含水率试样,进行不同围压下的固结排水三轴实验.研究表明土中水对压实花岗岩残积土具有较显著的软化作用,主要结论如下:1)土中水对强度的软化作用主要表现为粘聚力c的显著减小,而且随着含水率的增大,其软化效应成倍放大;2)在围压不大情况下(不超过100kPa),土中水对破坏偏应力的影响相当显著,但随着围压的增大,该影响减弱;3)邓肯-张模型的初始切线模量Ei值的变化基本可以反映土中水对压缩性的影响,而且同粘聚力c相似,土中水对压缩性的影响随含水率的增大呈放大趋势.A series of triaxial consolidation drained tests were done under different surrounding pressures for studying the pore waterrs softening effect on the compacted granite residual soil, in which the samples were of three different moisture contents based on its optimum moisture content with the same compactness. The research shows that pore water is of significant softening effect to the compacted granite residual soil, and its main conclusions as follows. 1）the pore waterrs softening effect on the strength mainly results in the decrease of the cohesion c significantly moreover, the softening effect is multiplied with the increase of moisture content 2）under the condition of low surrounding pressures（less than 100 kPa）, the pore wa- terrs softening effect on the damage deviatoric stress is rather significant, but with the increase of surrounding pressure, the influence is weakened; 3）essentially, the change of initial tangent modulus Ei in Duncan-Chang model may represent the pore water＇s influence on its compressibility, and similar with cohesion c , and the pore waterts effect on the compressibility shows a magnifying trend with the increase of moisture content.

关 键 词：花岗岩残积土 压实度 含水率 三轴试验 软化效应 邓肯—张模型 

分 类 号：TU411[建筑科学—岩土工程]