细粒含量对垫层料冻胀性的影响  

Impact of fine particle content on frost-heave of cushion material

作　　者：袁俊平[1,2] 丁鹏[1,2] 蔺彦玲 韩春雷[1,2] 王强林[1,2] 

机构地区：[1]河海大学岩土工程科学研究所,江苏南京210098 [2]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

出　　处：《水利水电技术》2016年第2期27-32,共6页Water Resources and Hydropower Engineering

基　　金：中央高校基本科研业务费专项资金(2014B04914);国家自然科学基金(51378008)

摘　　要：基于对寒冷地区面板堆石坝垫层冻胀变形大小进行研究,以细粒含量为研究重点,利用自制的试验装置,进行了系列室内冻胀试验,研究了不同细粒含量、相对密度对垫层料冻胀变形的影响规律。试验发现:细粒含量较小时,试样冻胀率随相对密度增大而增大;而细粒含量较大时,试样冻胀率随相对密度的增大先增加后减小。对基于孔隙模型试验结果的分析表明:垫层料冻胀率随表观孔隙数量n的变化呈现先增大后减小的规律,即存在一个临界值n*,当表观孔隙数量n超过该临界值时,垫层料冻胀率随表观孔隙数量n的增大反而减小。提出了有效孔隙数量n'的概念和计算办法,分析试验结果显示,垫层料冻胀率随有效孔隙数量n'呈单调变化趋势。Based on the study of the frost-heaving deformation degree of the cushion for concrete face rock fill dam in cold region,series frost-heaving experiment in laboratory is made with the self-made apparatus by taken the fine particle content as the study focus,and then the law of the impacts from various fine particle contents and relative densities on the frost-heaving deformation of the cushion materials are studied herein. The study finds out that the frost-heaving ratio increases along with the increase of the relative density,when fine particle content is relatively low; meanwhile,the frost-heaving ratio increases at first and then decreases along with the increase of the relative density for the higher fine particle content. The analysis based on pore distribution model test shows that the change of the frost-heaving ratio presents a law of increasing firstly and decreasing later along with the change of the apparent pore amount n＊,i. e. a critical value n is there,when the apparent pore amount is beyond this critical value,the frost-heaving ratio of the cushion materials contrarily decreases along with the increase of the apparent pore amount n.Therefore,the concept of the effective pore amount n＇ and its deriving method are put forward. The analysis and experiment result show that the frost-heaving ratio of the cushion materials changes monotonically with the of effective pore amount n＇.

关 键 词：垫层料 冻胀变形 细粒含量 孔隙分布 

分 类 号：TV641.43[水利工程—水利水电工程]