【作者】 申永江；

【导师】 尚岳全；

【作者基本信息】 浙江大学 ， 防灾减灾工程及防护工程， 2009， 博士

【摘要】 抗滑桩是滑坡治理中主要的工程措施之一,已在边坡工程中得到广泛应用。但是,抗滑桩的设计仍然存在诸多问题,结果还存在一些不确定性,尤其是双排抗滑桩的设计,更加不成熟。本文以现场监测和数值模拟分析为主要研究手段,结合现场调查和理论分析方法,研究抗滑桩与岩土体的相互作用机理,探索定量评价抗滑桩抗滑效果的方法,研究抗滑桩截面尺寸和桩间距的合理取值,分析桩项连接方式和桩排距对双排桩内力分布的影响。为抗滑桩合理设计和效果评价提供理论支持。主要研究内容如下:(1)分析土拱效应的存在条件和作用范围,系统研究矩形桩桩间土拱效应的形成发展过程,总结土拱效应的主要影响因素,揭示抗滑桩与岩土体相互作用的规律。(2)探索抗滑桩安全性评价方法。提出抗滑桩安全度和工作状态的概念,通过监测数据来计算抗滑桩的内力分布和剩余下滑力的方法。(3)根据合理拱轴线理论,运用结构力学方法,推导抗滑桩桩间距和桩截面尺寸的计算公式,对桩间距和桩截面尺寸的合理取值进行探讨。(4)总结目前双排抗滑桩设计中采用的几种桩顶连接方式,研究各种桩顶连接方式时前后排抗滑桩的弯矩和剪力分布以及侧向位移的分布,对比分析桩顶连接方式对内力和侧向位移分布的影响。(5)对双排抗滑桩的桩排距进行研究,分析桩排距对悬臂式双排桩、预应力锚索双排桩和带连系梁双排桩内力分布的影响,研究带连系梁双排桩中连系梁的截面尺寸和长度对内力分布的影响,探讨滑坡推力在悬臂式双排桩和带连系梁双排桩上的分配。通过上述内容研究,论文取得了以下一些创新成果:(1)提出两种基于抗滑桩的监测数据计算其内力分布的方法。一种由抗滑桩的侧向位移和钢筋的应力监测数据来推导其内力分布,另一种为直接由抗滑桩的侧向位移计算其内力分布。后一种方法依据测斜数据,运用正交多项式作最小二乘拟合位移曲线,推导出抗滑桩的侧向位移函数,再根据欧拉-伯努利梁理论得到抗滑桩的内力分布。(2)提出一种定量评价抗滑桩抗滑效果的方法。运用抗滑桩安全度和工作状态来评价抗滑桩的抗滑效果。通过监测数据直接计算抗滑桩的安全度,并得到抗滑桩的工作状态。(3)建立了抗滑桩截面尺寸和桩间距的计算模型,提出一种综合确定抗滑桩截面尺寸和桩间距的方法。(4)系统研究了双排桩的桩项连接方式对前后排抗滑桩内力和侧向位移分布的影响,提出前后排相连为桩顶连接的合理方式。(5)系统研究了桩排距对双排抗滑桩内力的影响,提出了计算作用于双排桩上滑坡推力的方法,给出了桩排距的合理取值。更多还原

【Abstract】 The anti-slide pile, which has been widely used in slope engineering, is one of the major engineering measures in the treatment of landslide. However, the design of piles still exist many problems, and the result of the design still has some uncertainties, especially the design of double row piles is more immature. In view of these problems, by means of a series of research methods, like site geologic survry, in-site monitoring and numerical analysis, studied the mechanism of anti-slide piles, and Put forward a method of quantitative evaluation of the effectiveness of anti-slide pile, and studied the reasonable value of the cross-section size and distance of anti-slide piles. In addition, studied the influence of the piles top connection way and the piles row distance to internal forces distribution of the double-row piles, and put forward some suggestions on selecting the reasonable piles top connection way and piles rowdistance. The main research contents are as follows:(1) The existence condition and action sphere of soil arching effect were analyzed. The development rules of soil arching effect between the rectangular section piles were systematically studied. The influencing factors of soil arching effects were summarized. It revealed the rules of pile-soil interaction around piles.(2) Put forward the evaluating methods of the safety of anti-slide Piles.The conception of safety degree and operating state was put forward. The internal forces and landslide thrust were estimated by bank analysis based on the monitoring data.(3) Based on the soil arching theory. the calculation formulas of the cross-section size and distance of anti-slide piles were deduced from the mechanical equilibrium equation and the strength condition of soil arching. The reasonable values of cross-section size and distance of piles were discussed.(4) The types of piles top connection ways were summarized in the design of double-row piles at present. Analyzed the effect of piles top connection way on the internal forces and lateral displacement of the fore-and-aft row piles.The optimal piles top connection way was found.(5) The piles row distance of double-row piles was systematically studied. The influence of the piles row distance and the connecting beam to the internal forces of the double-row piles was studied. The distribution of the landslide thrust on double-row piles was discussed.And the the dissertation’s main innovative results are as follows:(1) Given two methods to calculate the distribution of internal forces of anti-slide piles. The one is by the monitoring data of the lateral displacement and reinforced stress to deduce the internal forces distribution, the other is directly by the monitoring data of the lateral displacement. As to the last one, based on the inclinometer data, the function of pile lateral displacement could be deduced from least-squares curve fitting by orthogonal polynomials, and then according to Euler-Bernoulli beam theory internal force distribution the internal forces distribution of anti-slide piles could be calculated from the displacement function.(2) Put forward the quantitative evaluation method of anti sliding property of anti-slide piles. The safety degree and operating state were used to evaluate anti sliding property of anti-slide piles. The operating state can be deduced from in-site monitoring data.(3) The calculation model of the cross-section size and distance of anti-slide piles was established.A method of comprehensively determining the cross-section sizeand distance was put forward.(4) The effect of piles top connection way on the internal forces and lateral displacement of the fore-and-aft row piles was systematically studied. It reveals that the front-and-bank rows connection is most reasonable.(5) The influence of the piles row distance to the internal forces of the double pile was systematically studied. The calculation method of the distribution of landslide thrust on the fore-and-aft row piles was established.The reasonable value of piles row distance was put forward.更多还原