悬臂式抗滑桩受力特性分析及桩间距计算  

Analysis of force characteristics of cantilever anti-slide pile and pile spacing calculation

作　　者：林斌[1] 李怀鑫 范登政 王鹏 LIN Bin;LI Huaixin;FAN Dengzheng;WANG Peng(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China;China Railway 14th Bureau Group Co.,Ltd.,Ji’nan 250000,China)

机构地区：[1]安徽理工大学土木建筑学院,安徽淮南232001 [2]中铁十四局集团有限公司,山东济南250000

出　　处：《人民长江》2021年第4期177-181,共5页Yangtze River

基　　金：高校博士点专项基金资助项目(200803610004);安徽理工大学创新基金项目(2019cx2017)。

摘　　要：为得到抗滑桩的合理桩间距计算公式,在假定桩后土拱和桩侧土拱充分发挥阻滑能力的基础上,将土拱极限剪切面和桩侧面上的摩阻力进行简化,根据桩间土体静力平衡条件及Mohr-Coulomb强度准则计算出了合理的桩间距,并通过工程实例和数值模拟进行了对比验证,进一步分析了桩间距的影响因素及不同桩间距下土拱的受力情况。研究结果表明:安全系数一定时,计算得到的桩间距随凝聚力和桩截面宽长比的增加而线性增加;抗滑桩正面宽度对桩间距的敏感性随桩间距的增加而降低,抗滑桩侧面宽度对桩间距的敏感性随桩间距的增加而增加;随着桩间距的增加,桩后拱脚处塑性区逐渐变大,桩后端承拱成拱效应逐渐减弱直至消失的过程先于桩侧摩擦拱,由桩后端承拱分担的滑坡下滑力逐渐转移到桩侧摩擦拱上。In order to obtain the calculation formula of reasonable pile spacing of anti-slide piles in practical engineering, based on the assumption that the soil arch behind the pile and the soil arch at the side of pile can fully exert resistance to sliding, the limit shear surface of soil arch and frictional resistance on side of pile are simplified.The reasonable pile spacing of anti-slide pile is calculated by the static balance of soil mass between piles and the Mohr-Coulomb strength criteria, and the calculation results is verified by the engineering examples and numerical simulation.In addition, the influencing factors for anti-slide pile spacing and the stress of soil arch under different pile spacing are further analyzed.The results show that when assuming the safety coefficient being a constant, the pile spacing increased lineally with increase of soil cohesive force and the ratio of width to length of pile section;while the sensitivity of pile width to pile spacing increased with the increase of pile spacing.The plastic zone at the rear arch foot of the anti-slide pile gradually increased with the increase of pile spacing, and the arching effect of end bearing arch at pile back gradually weakened and finally disappears, which was prior to the disappear of friction arch effect, so sliding force shared by the end bearing arch gradually transfers to the friction arch on the side of pile.

关 键 词：抗滑桩 桩间距 土拱效应 Mohr-Coulomb强度准则 数值模拟 

分 类 号：P642[天文地球—工程地质学]