【作者】 吴能森；

【导师】 赵尘； 侯伟生；

【作者基本信息】 南京林业大学 ， 森林工程， 2005， 博士

【摘要】 花岗岩残积土在我国南方广泛分布,随着基本建设的发展,其地基和边坡等工程问题日益突出。论文首次从损伤力学角度研究花岗岩残积土“大孔隙比、高压缩性与高强度”工程特性的结构性原因,主要工作和取得的成果如下: 在理论研究方面,提出花岗岩残积土微结构损伤的物理模型和扰动损伤因子的确定方法;对花岗岩残积土的分类原则和标准进行全面系统地研究,提出新的分类方法;通过一系列压缩试验及原位静载试验,研究侧向应力卸荷、失水干缩、饱和软化等扰动损伤因素对其压缩性的影响;用自行研制的简易试验装置研究扰动损伤对花岗岩残积土崩解性的影响,提出将其崩解分为3 个阶段及其各自的崩解机理;通过抗剪强度指标和结构性影响因素的分析研究,揭示扰动损伤影响主要体现为其粘聚力的减小,并通过直剪和三轴试验予以论证,尝试性地提出用e-logp 曲线进行粘聚力修正的方法。在工程问题研究方面,结合厦门某工程,首次进行花岗岩残积土旋喷桩复合地基的工程应用研究,创新性地构想了“水浆隔离法”工艺,经多次反复试验,取得比较理想的工程效果;首次归纳并提出花岗岩残积土路堑边坡失稳的4 种组合滑动面形式,设计开发了能考虑结构面效应的路堑边坡稳定分析及防护设计软件,经工程算例验证是正确可行的;此外,从扰动损伤角度,提出一种路堑边坡防护加固新措施。更多还原

【Abstract】 The granite residual soil (GRS) is widely distributed over South of China,as development of capital construction,its engineering problems in groundworks and slopes are increasingly stand out as result of lack of knowledge on its structure nature. In this paper,based on damage mechanics, the structural damage reason for the GRS unusual physic & mechanic character of “macro-void ratio,high compressibility vs. high strength”was investigated for the first time,main results of the studies as follows. On theoretical studies,a physical model for unpuzzling the microstructure damage of GRS and the determination means for the damage factor of the elastoplastic damage model were put forward with exploration;The classification principle and criterion for GRS were examined and investigated comprehensively, and then, a new classification method for GRS was constructively brought forward;After a series of confined compression tests and dead-load in-situ tests in a engineering project were carried out for GRS, comprehensive and systematic researches were launched on the compressibility effect on GRS caused by same damage factors such as lateral stress unloading, dry shrinkage, saturation;The disintegration test in water for several GRS samples with different disturbance were launched with a simple self developed device, the mechanism on disintegrating process which was divided into three stages of surface, structure and dissolution disintegration was put forward;After affecting factors on the shear strength and structure natures of GRS were analyzed, the conclusion was advanced that the effect of disturbance damage on GRS structure mainly results in a decrease in the cohesive force of GRS, which were demonstrated by shear box and triaxial shear tests. And the method on correcting cohesive force with the e-logp curve was brought forward experimentally. On studies in engineering problems,GRS circle-jet-mixing compound pile foundation was studied by an engineering project in Xiamen city in Fujian province for the first time. After tried time after time, the innovative technics so-called “water & cement grout separated method”was brought forward, and the rather ideal result was achieved in the engineering project eventually. The four types of composite sliding surfaces for GRS cutting slopes was summed up and advanced for the first time, and the software for analyzing slope stability and designing protective structures which can consider the effect of structural surfaces have been designed and developed, which was verified by some engineering examples. Based on disturbance damage point of view, a new measure for protecting and reinforcing GRS cutting slopes has been exploratory put forward.更多还原