摘要
针对深基坑工程防渗墙与双排桩组合的复杂新型截渗结构,采用三维渗流分析方法,研究双排桩咬合部位出现裂缝对深基坑截渗体系渗控效应的影响,考虑桩间裂缝影响下优化防渗墙布置。结果表明:防渗墙与双排桩可有效控制基坑渗漏,渗控效应会受桩间裂缝开裂程度以及防渗墙布置深度与渗透性的影响。基坑渗流量及防渗墙折减水头值随裂缝开裂程度增大而增加,防渗墙渗透性质量要求随裂缝开裂程度增大而提高。裂缝区域渗透系数小于2.45×10^(-4) cm/s,仅双排桩即可满足基坑防渗要求;随着裂缝区域渗透系数增大,双排桩截渗能力迅速减弱,防渗墙渗透系数小于1×10^(-6) cm/s,并将透水性强的覆盖层截断时,截渗体系渗控效应明显,若继续提升防渗墙质量和布置深度则效果不显著。当裂缝区域渗透系数达到2.8×10^(-3) cm/s,双排桩止水失效,防渗墙承担全部削减水头任务。
Aiming at the complex new type of seepage interception structure combined with impermeable wall and doublerow piles in deep foundation pit engineering,the three-dimensional seepage analysis method is used to study the influence of cracks in the interlocking part of double-row piles on the seepage control effect of deep foundation pit seepage interception system,and the layout of impermeable wall is optimized considering the influence of cracks between piles.The results show that the impermeable wall and double-row piles can effectively control the leakage of the foundation pit,and the seepage control effect will be affected by the degree of crack cracking between piles and the depth and permeability of the impermeable wall.The seepage flow of foundation pit and the reduction head value of impermeable wall increase with the increase of crack cracking degree,and the permeability quality requirement of impermeable wall increases with the increase of crack cracking degree.The permeability coefficient of the crack area is less than 2.45×10^(-4) cm/s,and only double-row piles can meet the anti-seepage requirements of the foundation pit.With the increase of the permeability coefficient in the crack area,the seepage control ability of the double-row piles decreases rapidly.When the permeability coefficient of the impermeable wall is less than 1×10^(-6) cm/s and the overburden layer with strong permeability is cut off,the seepage control effect of the seepage interception system is obvious.If the quality and layout depth of the impermeable wall are continuously improved,the effect is not significant.When the permeability coefficient of the crack area reaches 2.8×10^(-3) cm/s,the water stop of the double-row piles fails,and the impermeable wall undertakes all the tasks of reducing the water head.
作者
刘武
尚金行
严周为
张康
陈世威
袁文俊
LIU Wu;SHANG Jinhang;YAN Zhouwei;ZHANG Kang;CHEN Shiwei;YUAN Wenjun(School of Civil Engineering,Hefei University of Technology,Hefei 230009,China;Anhui Shui'an Construction Group Co.,Ltd.,Hefei 230601,China)
出处
《金属矿山》
北大核心
2025年第2期198-205,共8页
Metal Mine
基金
安徽省自然科学基金项目(编号:2208085ME153,2308085US07)
安徽高校协同创新项目(编号:GXXT-2022-020)
国家自然科学基金项目(编号:51979068)。
关键词
桩间裂缝
深基坑
三维渗流
防渗结构优化
渗流控制
inter-pile cracks
deep foundation pits
three-dimensional seepage
optimization of impermeable structures
seepage control
