摘要
珊瑚岛礁地基处理问题日益突出,为研究珊瑚砂场地的振冲加固处理效果,分别对振冲加固的珊瑚砂地基和未经振冲加固的松散珊瑚砂地基进行振动台模型试验,收集并对比分析了孔隙水压力和加速度响应规律。结果表明,振冲加固后的珊瑚砂地基在经历0.1g地震时超孔压持续缓慢增长并直至激励结束,未经振冲加固的珊瑚砂地基在激励输入3~4 s内超孔压迅速上升并达到稳定,并且整个地震模拟过程中加固地基超孔压始终小于未加固地基。振冲可有效降低地震输入时珊瑚砂地基的超孔压发展,振冲加固后的珊瑚砂地基在0.1g地震作用下超孔压较未加固的松散状态下降了37.2%~67.3%。经振冲加固后的珊瑚砂地基可有效减少加速度的放大效应。振冲加固后的放大系数为未加固地基的78.1%~91.1%。
The foundation treatment of coral islands is becoming more and more serious.Shaking table tests were carried out on coral sand foundation reinforced by vibroflotation and loose coral sand foundations not reinforced by vibroflotation.The responses of excess pore pressures and accelerates were collected and analyzed.The results indicated that the excess pore pressures of vibroflotation-reinforced coral sand foundation continued to increase until the end of excitation when experienced 0.1g seismic simulation,while these of the unreinforced loose foundation raised rapidly at 3~4 s and kept stable until the excitatory input ended.In the whole seismic simu-lation process,the excess pore pressure of a reinforced foundation is always smaller than that of an unreinforced one.Vibroflotation can effectively reduce the development of excess pore pressure in coral sand foundations under seismic input.The excess pore pressure of the coral sand foundation reinforced by vibroflotation decreased by 37.2%~67.3%under 0.1g seismic simulation compared with the un-reinforced loose condition.Moreover,the coral sand foundation reinforced by vibroflotation can effectively reduce the amplification ef-fect of acceleration.The amplification coefficient after vibroflotation reinforcement is 78.1%~91.1%of that of the unreinforced founda-tion.
作者
段志刚
王建平
赵津桥
丁选明
Duan Zhigang;Wang Jianping;Zhao Jinqiao;Ding Xuanming(Naval Postgraduate School,Bejing 102202,China;School of Civil Engineering,Chongqing University,Chongqing 400045,China)
出处
《岩土工程技术》
2023年第6期720-724,共5页
Geotechnical Engineering Technique
基金
军队后勤科研资金资助项目(BHJ16J032)
军队后勤科研开放项目(BHJ18009)(BHJ20J005)。
关键词
珊瑚砂
振冲法
振动台试验
超孔隙水压力
加速度
coral sand
vibroflotation
shaking table test
excess pore pressure
acceleration
