摘要
岛礁在吹填过程中会形成珊瑚砂与珊瑚砾石相互交替的层状地基。为研究珊瑚砂砾交互地层地基的承载特性,通过室内模型试验,开展了纯砂、纯砾均质地基以及不同层厚比例砂砾互层地基的承载特性研究。试验结果表明:纯砂地基的承载力和变形模量随相对密实度的增大而增大,且密实地基的承载力明显高于中等密实地基;相同相对密实度下,纯砾地基的承载力和变形模量是纯砂地基的2倍以上;上砾下砂地基的承载力随砾层厚度的增大而增加,砾层具有一定的应力扩散作用,厚度越大,应力扩散越明显;上砂下砾地基的承载力随砾层埋深的减小而增大,地基下卧砾石层能使地基内一定深度处应力集中程度减弱,埋深越浅,减弱程度越大。试验结果对于确定砂砾互层地基的天然承载力及持力层选择具有重要意义。
During the dredger filling process of island reefs,a layered foundation of coral sand and coral gravel will be formed.We investigated the bearing characteristics of pure sand,pure gravel homogeneous foundation and sand-gravel interlayer foundation with different layer thickness ratio by indoor model tests.The test results showed that the bearing capacity and deformation modulus of pure sand foundation increased with the relative density,and the bearing capacity of dense foundation was obviously higher than that of medium dense foundation;the bearing capacity and deformation modulus of pure gravel foundation were more than twice of that of pure sand foundation under the same relative density;the bearing capacity of upper gravel and lower sand foundation increased with the increase of gravel layer thickness,and the gravel layer had a certain stress diffusion effect,and the larger the thickness,the more obvious the stress diffusion.The bearing capacity of upper sand and lower gravel foundation increased with the decreasing of gravel layer depth,and the lying gravel layer under the foundation can weaken the stress concentration at a certain depth in the foundation,the shallower the depth,the greater the weakening degree.The test results are of great significance for determining the natural bearing capacity of sand and gravel interlayer foundation and the selection of bearing layer.
作者
付金鑫
雷学文
孟庆山
潘剑锋
FU Jinxin;LEI Xuewen;MENG Qingshan;PAN Jianfeng(City Construction Institute,Wuhan University of Science and Technology,Wuhan 430065,China;State Key Laboratory of Geomechanics and Geotechnical Engineering,Institute of Rock and Soil Mechanics of Chinese Academy of Sciences,Wuhan 430071,China)
出处
《人民长江》
北大核心
2023年第4期183-189,共7页
Yangtze River
基金
国家自然科学基金面上项目(41877267,41877260)
中国科学院战略性先导科技专项(A类)(XDA13010201)。
关键词
珊瑚砂砾互层地基
地基承载力
变形模量
土压力分布
P-S曲线
coral sand and gravel interlayer foundation
foundation bearing capacity
modulus of deformation
soil pressure distribution
p-s curve
