采用波动方法探测土石混合体结构特性的可行性研究  

FEASIBILITY STUDY OF WAVE METHOD FOR DETECTING STRUCTURAL PROPERTIES OF SOIL-ROCK MIXTURES

作　　者：张亚南[1] 冯春[1] 李世海[1] 

机构地区：[1]中国科学院力学研究所,北京100190

出　　处：《岩石力学与工程学报》2011年第9期1855-1863,共9页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家重点基础研究发展计划(973)项目(2010CB731506);国家自然科学基金重点项目(10632100)

摘　　要：将土石混合体概化为由土体和块石随机分布构成的宏观致密和等效均匀介质,将深部爆源的爆炸效果用等效冲击载荷代替,以基于连续介质力学的离散元方法(CDEM)的计算程序为平台,以模型均匀随机技术为条件,通过研究土石混合体内部结构特性对应力波传播过程的影响,建立波动响应与内部结构特性(包括含石率、块石特征尺寸和土石分布规律)之间的对应关系。研究结果表明:在一定载荷条件及材料性质下,加速度波的最大振幅和主频受含石率和块石特征尺寸的影响有着规律性的变化;均匀分布情况下,不同分布规律对于波动响应的影响很小,可以忽略;分别给出随含石率和块石特征尺寸变化的波动响应规律(最大振幅、主频)拟合曲面,且最大振幅和主频的值满足实际工程的可测性;以给定波动响应情况为例,通过已知最大振幅和主频易在拟合影响曲面上查出含石率和块石特征尺寸。从规律性、可测性和易操作性3个方面说明采用波动方法探测土石混合体结构特性的可行性。Soil-rock mixtures are seen as the macro-density and equivalent homogeneous medium constituted by soil and rock under random distribution;and the explosion effect of deep explosion source is replaced by equivalent impact load.The platform of continuum media mechanics of discrete element method（CDEM） is used;and the uniform random technique is adopted.By studying the impact of internal structural properties of soil-rock mixtures on stress wave propagation process,the relationships between internal structural properties（including percentage of rock,feature size of rock block and distribution of soil-rock） and wave responses are established.The study results show that in certain of the same loading and material properties,the maximum amplitude and dominant frequency of acceleration wave have regular changes under the effect of percentage of rock and feature size of rock block.Under the uniform distribution,the impact of different distributions of soil-rock on wave response is very small and can be neglected.The fitting surfaces of wave response（maximum amplitude and dominant frequency） with the variations of percentage of rock and feature size of rock block are given;and the maximum amplitude and dominant frequency both meet the testability of actual project.Taking an assigned wave response for example,percentage of rock and feature size of rock block are given easily on the fitting impact surface by means of the assigned maximum amplitude and dominant frequency.The feasibility of wave method for detecting structural properties of soil-rock mixtures is illustrated from three aspects of regularity,testability and handleability.

关 键 词：岩石力学 土石混合体 波动方法 含石率 块石特征尺寸 土石分布 

分 类 号：TU45[建筑科学—岩土工程]