岩石力学与工程学报
巖石力學與工程學報
암석역학여공정학보
CHINESE JOURNAL OF ROCK MECHANICS AND ENGINEERING
2015年
z1期
3564-3573
,共10页
田湖南%焦玉勇%王浩%马江锋
田湖南%焦玉勇%王浩%馬江鋒
전호남%초옥용%왕호%마강봉
土力学%土石混合体%颗粒流%碎石形状%力学特性
土力學%土石混閤體%顆粒流%碎石形狀%力學特性
토역학%토석혼합체%과립류%쇄석형상%역학특성
soil mechanics%soil-rock aggregate(SRA)%particle flow code(PFC)%rock block shape%mechanical characteristics
土石混合体作为土体和碎石的混合体,其宏观力学特性与碎石特性密切相关。采用试验研究和数值模拟相结合的方法,对土石混合体的力学特性进行研究。基于FISH语言开发颗粒流的多边形碎石生成模块,通过室内试验校核颗粒流模型的细观参数,建立土石混合体双轴试验模型。提出以形状因子m作为衡量碎石磨圆度的指标,对碎石形状进行了量化。研究了碎石含量、强度、形状对土石混合体力学特性影响,探讨碎石对土体强度提高的细观原因,揭示土石混合料的强度指标随各主要影响因素的变化趋势。结果表明:碎石含量和强度越高,混合体的强度也越高,当含石量小于40%时,土石混合体的力学特性受土体主导;内摩擦角随着碎石含量增加而增大,而黏聚力却在减小;随着形状因子的增大,强度降低,黏聚力和内摩擦角均减小;土石混合体中应力分布不均,在碎石含量较高时,碎石形成骨架效应,承担了主要荷载。
土石混閤體作為土體和碎石的混閤體,其宏觀力學特性與碎石特性密切相關。採用試驗研究和數值模擬相結閤的方法,對土石混閤體的力學特性進行研究。基于FISH語言開髮顆粒流的多邊形碎石生成模塊,通過室內試驗校覈顆粒流模型的細觀參數,建立土石混閤體雙軸試驗模型。提齣以形狀因子m作為衡量碎石磨圓度的指標,對碎石形狀進行瞭量化。研究瞭碎石含量、彊度、形狀對土石混閤體力學特性影響,探討碎石對土體彊度提高的細觀原因,揭示土石混閤料的彊度指標隨各主要影響因素的變化趨勢。結果錶明:碎石含量和彊度越高,混閤體的彊度也越高,噹含石量小于40%時,土石混閤體的力學特性受土體主導;內摩抆角隨著碎石含量增加而增大,而黏聚力卻在減小;隨著形狀因子的增大,彊度降低,黏聚力和內摩抆角均減小;土石混閤體中應力分佈不均,在碎石含量較高時,碎石形成骨架效應,承擔瞭主要荷載。
토석혼합체작위토체화쇄석적혼합체,기굉관역학특성여쇄석특성밀절상관。채용시험연구화수치모의상결합적방법,대토석혼합체적역학특성진행연구。기우FISH어언개발과립류적다변형쇄석생성모괴,통과실내시험교핵과립류모형적세관삼수,건립토석혼합체쌍축시험모형。제출이형상인자m작위형량쇄석마원도적지표,대쇄석형상진행료양화。연구료쇄석함량、강도、형상대토석혼합체역학특성영향,탐토쇄석대토체강도제고적세관원인,게시토석혼합료적강도지표수각주요영향인소적변화추세。결과표명:쇄석함량화강도월고,혼합체적강도야월고,당함석량소우40%시,토석혼합체적역학특성수토체주도;내마찰각수착쇄석함량증가이증대,이점취력각재감소;수착형상인자적증대,강도강저,점취력화내마찰각균감소;토석혼합체중응력분포불균,재쇄석함량교고시,쇄석형성골가효응,승담료주요하재。
The soil-rock aggregate(SRA) is composed of soil and rock block and the mechanical characteristics of SRA are closely related to features of rock block. A combination method of experiment research and numerical simulation has been used to study the mechanical properties of SRA. The polygonal rock block generation module was developed using the FISH language. Through laboratory experiments,the relation between macro- and meso-properties was studied. The shape factorm is proposed to quantify the psephicity of rock block. The PFC model of SRA was established to analyze the effects of rock block features(such as rock block content,rock block strength and rock block shape) on mechanical characteristics of SRA. The micro reason for enhancing strength performance of the SRA which contains a certain amount of rock block was studied. The change tendency of SRA strength parameters affected by factors was revealed. The simulation results indicate that the shear strength of SRA increases with the increase of rock block content and rock block strength. When the rock block content is less than 40%,the mechanical characteristics of SRA are dominated by soil. The internal friction angle increases and the cohesion decreases linearly with the increase of rock block content. With the increase of the shape factor m the shear strength of SRA decreases,and the internal friction angle and cohesion decreases. The stress distribution is uneven in SRA. The rock blocks,which generate skeleton,bear the majority of the load.