粗粒含量对珊瑚礁砂混合体剪切特性的影响  

Effect of Coarse-grain Content on Shear Properties of CoralReef-Sand Mixtures

作　　者：潘剑锋 雷学文[1] 孟庆山[2] 覃东来 付金鑫 PAN Jian-feng;LEI Xue-wen;MENG Qing-shan;QIN Dong-lai;FU Jin-xin(School of Urban Construction,Wuhan University of Science and Technology,Wuhan 430065,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics,Chinese Academy of Sciences,Wuhan 430071,China;University of Chinese Academy of Sciences,Beijing 100049,China;Southwest Engineering Corporation Limited of China Communications Construction First Harbor Engineering Bureau,Yulin 537000,China)

机构地区：[1]武汉科技大学城市建设学院,武汉430065 [2]中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室,武汉430071 [3]中国科学院大学,北京100049 [4]中交一航局西南工程有限公司,广西玉林537000

出　　处：《长江科学院院报》2023年第5期118-124,共7页Journal of Changjiang River Scientific Research Institute

基　　金：国家自然科学基金项目(41877267,41877260,41472287);中国科学院战略性先导科技专项(A类)(XDA13010201)。

摘　　要：珊瑚礁砂混合体是基础设施重要持力层,为了探究颗粒级配组成对珊瑚礁砂混合体的抗剪强度及剪胀性的影响,利用全自动中型叠环直剪仪,在相同密实度下,对不同P5含量、不同含水率的试样,在50、100、200、400 kPa这4种不同法向应力下进行单剪试验。试验结果表明,珊瑚礁砂混合体的抗剪强度随着P5含量的增加呈现先增大后减小的趋势,并在P5含量为25%~50%时达到最大值;珊瑚礁砂混合体在剪切过程中,总体存在先减缩后剪胀的特点,P5含量对剪胀性、内摩擦角、似黏聚力都有着显著影响;含水率对珊瑚礁砂混合体的抗剪强度有着减弱作用。Coral reef-sand mixture is an important supporting layer of infrastructure.To investigate the effect of particle gradation composition on shear strength and dilatation of coral reef-sand mixtures,simple shear tests were performed using fully automatic medium-sized stacked ring direct shear instrument.The tests were conducted on samples with varied P 5 content and water content under four different normal stresses of 50,100,200,and 400 kPa.The experimental results show that the shear strength of coral reef-sand mixtures first increases and then decreases with the increase of P 5 content.The shear strength reaches its maximum when P 5 content is 25%-50%.In the shearing process,coral reef-sand mixtures contracted first and then dilated.P 5 content has a significant effect on dilatation,internal friction angle,and apparent cohesion.Water content weakens the shear strength of coral reef sand mixture.

关 键 词：珊瑚礁砂混合体 P5含量 单剪试验 剪切特性 含水率 

分 类 号：TU411[建筑科学—岩土工程]