冲击载荷作用下土的疲劳损伤特性分析  

Study on the fatigue damage properties of foundation soil under impact loading

作　　者：任廷鸿 张我华[2] 薛新华[3] 

机构地区：[1]贵州省水利厅,贵州贵阳550002 [2]浙江大学建筑工程学院,浙江杭州310027 [3]四川大学水力学与山区河流开发保护国家重点实验室,水利水电学院,四川成都610065

出　　处：《水利学报》2014年第5期619-625,共7页Journal of Hydraulic Engineering

基　　金：国家自然科学基金项目资助(50376046)

摘　　要：疲劳失效是发生在工程领域中的一类十分普遍的物理现象,用连续损伤力学理论研究岩土工程结构的冲击疲劳损伤过程不论对损伤力学研究发展还是岩土工程理论进步都有创新意义。由于土具有结构性,所以国内外有很多学者在土的本构模型中都引入了"损伤"的概念。但是,在循环荷载作用下,将土的破坏视为疲劳损伤破坏的文章尚不多见。通过对锻锤基础系统的冲击疲劳损伤数值分析,得到了锻锤基础系统在不同寿命阶段(总锻打次数下)单次锻打引起地基土竖向响应、微损伤平均累积变化量以及用宏观平均累积损伤表示的冲击疲劳损伤变量的机理和演变规律,可供类似锻锤基础系统设计时参考。Fatigue failure is an important phenomenon in many engineering projects. The study of the impact fatigue damage process in structures of geotechnical engineering has advanced function for development either in continuum damage mechanics or in geotechnical engineering applications. Because of the structural behavior in soils,many national and international scholars have introduced“damage”conception into constitutive models of soils. However, the papers deal with the point of view on the soil failure under cyclic loading as the fatigue damage of soils failure still have not been seen widely. In this paper, Mechanism and the law of evolvement for vertical response of soils, micro-damage average cumulative variable and impact fatigue damage variable represented by microscopically average cumulative damage are obtained through numerical experimentation of impact fatigue damage for hammerfoundation system. For the analysis of ham-mer-foundation system,the estimate formula can be used as reference for designer.

关 键 词：冲击荷载 锻锤基础系统 疲劳寿命 损伤 

分 类 号：TU432[建筑科学—岩土工程]