基于级配方程的粗粒料级配演化预测模型  

Mathematical model based on the gradation equation for predicting gradation evolution of coarse-grained soils

作　　者：郭万里[1] 朱俊高[1] 王青龙 余挺[2] GUO Wanli;ZHU Jungao;WANG Qinglong;YU Ting(Chengdu Survey and Design Institute Limited,Power Construction Corporation of China,Chengdu 610072,China)

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,江苏南京210098 [2]中国电力建设集团成都勘测设计研究院有限公司,四川成都610072

出　　处：《中南大学学报（自然科学版）》2018年第8期2076-2082,共7页Journal of Central South University:Science and Technology

基　　金：国家重点研发计划项目(2017YFC0404801);国家自然科学基金资助项目(51479052)~~

摘　　要：为了揭示粗粒料级配随应力应变演化的规律,建立粗粒料"应力应变→破碎指标→级配分布"的数学模型(SBG模型)。首先,引入1个适用性良好的级配方程来描述土体的级配,其级配参数为b和m;同时,定义1个新的破碎指标BW,并将BW和破碎指标Bg建议为该模型所需的2个破碎指标。其次,推导并且验证BW和Bg与级配参数b和m的数学关系,实现"破碎指标→级配分布"这一目标。根据粗粒料的三轴试验结果总结三轴试样破坏时BW和Bg与围压σ3之间的关系、三轴试样在剪切过程中BW和Bg与平均正应力p和广义剪应变εs之间的关系,实现"应力应变→破碎指标"这一目标。将以上2个部分联合,即可得到"应力应变→破碎指标→级配分布"的数学模型(SBG模型)。研究结果表明:本文提出的模型可以用来描述三轴应力状态下粗粒料级配随应力应变演化的规律。In order to study the evolution law of gradation for coarse-grained soils,a mathematical model describing the relationship between stress and strain state,breakage indicators and gradation(SBG model)was established.Firstly,a gradation equation in which the two gradation parameters were named b and m was proposed to describe the grain size distribution(GSD)curve.Then,a new grain breakage indicator BW was defined.Together with another breakage indicator Bg,they were both suggested as the two required breakage indicators for the proposed model.On one hand,the relationship between BW and Bg and the gradation parameters b and m were derived and verified.On the other hand,an empirical equation of BW and Bg and confining pressure at the failure of the specimens,and an empirical equation of BW and Bg and the mean normal stress and general shear strain during shearing of the specimens were proposed.The SBG model was thereby established by combining the above two parts.The results show that the proposed SBG model can be used to predict change of breakage indicators and GSD of coarse-grained soils with stress and strain states in triaxial test.

关 键 词：粗粒料 颗粒破碎 级配方程 级配演化 三轴试验 

分 类 号：TU43[建筑科学—岩土工程]