Based on the engineering practices and indoor model exams , and according to the distortion character of the holding sheet , the paper obtains that it is the distortion character of the holding sheet induces the forming of the unloading arch . on the effect of the unloading arch , the soil pressure behind the sheets is transferred to the columns . the sheets only support the soil pressure inside the arch 在对工程实践及室内模型试验进行分析探讨的基础上，本文以挡板的变形特征为理论分析出发点，得出正是由于挡板的变形特征导致挡板后卸荷拱的形成，在卸荷拱的作用下，挡板后土体直接将土压力作用于桩锚立柱上，而挡板仅承受卸荷拱体内土体的土压力的结论。
It has improved the conventional optimal design methods by simplifying the variables and the optimal program . it considers the bending moment as the main objective function , while the conventional methods regard the construction cost as the objective function . a model has been applied to the prediction of the deformation of pile - anchor systems by using matlab toolbox 从基坑动态设计的观点出发，借助matlab工具箱，建立了深基坑桩锚支护体系变形预测模型，以大量实测变形数据资料为基础，说明采用神经网络对基坑支护系统的位移进行预测是可行的。
Anti - sliding pile especially the pile with prestressed anchor cable and the foundation beam with prestressed anchor cable including the single beam and the frame , are the new pattern structures of the pile - anchor system that have been widely used in the slide - resistant engineering . studies on designing theory of these structures are delayed greatly than their applications . there are no specifications to consult and there are many problems when designing and computing these structures 抗滑桩尤其是预应力锚索抗滑桩和预应力锚索地梁(包括单梁和框架梁)是近年来较多地应用于抗滑工程的新型桩锚结构，这些结构的设计理论研究大大滞后于工程应用，其设计计算缺乏相应的规范作指导，存在的问题较多。
Thirdly , the bearing mechanism of composite soil nailing system was studies by field monitoring , pointed the difference between composite soil nailing system and soil nailing system , discussed the bearing mechanism of supporting structures , compared the result of monitoring with the prediction of numerical simulation , summarized the experiences and lessons from field monitoring . the principal conclusions include : there is interaction between pile - anchor supporting and soil nailing , soil nailing will make a thrust to the pile top , the change of pile - anchor ’ s parameters will influence the axial force of soil nails ; the potential 主要结论有:土钉支护和桩锚支护之间存在相互作用,土钉支护会给桩端一定的推力,桩锚参数的变化也会影响土钉轴力;土钉支护部分的潜在破裂面与规程相差较大,特别是在下部;土钉轴力分布呈中间大、两端小的形式,桩顶之后的开挖过程对土钉轴力的影响较小;土钉支护部分水平位移上部线性增大,下部呈锯齿状分布。
According to test results , author analyses deformation characters and its rules of prestress anchor cable composite soil nail supporting and pile anchor composite soil nail supporting , studies work mechanism of prestress anchor cable composite soil nail supporting structure , explores change regularity of inner force of soil 三、对预应力锚索复合土钉支护结构进行了大量全方位的现场原位测试试验。根据试验测试结果来研究分析预应力锚索复合土钉支护结构和桩锚式复合土钉支护结构的变形特征及规律。
The pile - anchor retaining structure system is often used in chongqing area . for a long time , there is a conception about the transfer approach of soil pressure behind the pile - anchor retaining structure system that the pressure is applied on the holding sheet firstly , then transferred to the columns by the sheet , finally transferred to the form ground by the anchor 桩锚支挡结构体系是重庆地区经常采用边坡支护形式之一，长期以来，人们认为桩锚支挡结构体系的传力途径是：土压力先作用于挡板上，通过挡板再传到两边立柱，然后再通过锚杆把力传递给稳定地层。
Pile - anchor composite soil nailing system which takes over many advantages of both and remedies a number of defects of soil nailing system , has been made widely application in deep - excavated retaining engineering . although some studies which acquire some theories have been carried out , knowledge of bearing mechanism and working mechanism is still not very clear , design of the system and theoretical system is imperfect 桩锚复合土钉支护综合了土钉支护和桩锚支护两者的优点,弥补了土钉支护许多缺陷,在深基坑开挖支护中得到了广泛应用,虽然国内外对其已经进行了一些研究,取得了一些成果,但目前对其承载机理、工作性能的认识还不够深入,设计方法也不够完善,没有形成较完整的理论体系。
In this article , geotechnical engineering numerical analysis program flac4 . 0 is used , working mechanism and main influential factor of composite soil nailing system with step excavation was calculated in detailed , contain distribution and influential factors of axial force and the max axial force in soil nails ; the variation of axial force in anchors ; the variation and influential factor of foundation pit horizontal displacement , ground surface settlement , ground surface horizontal displacement and rebound deformation 本文采用岩土工程数值分析软件flac4 . 0 ,对桩锚复合土钉支护在分步开挖下的工作性能和主要影响因素进行了详细的计算,分析了土钉轴力和最大轴力的分布规律、影响因素;锚杆轴力的变化规律;基坑水平位移、地表沉降、地表水平位移和坑底隆起的变化规律以及影响因素的敏感程度。
In this paper , based on the characteristics of force and deformation of pars , the time - variation of the elastic coefficient of fulcrum in the calculation model of pars is analyzed and studied ; and the lessening of rigidity coefficient of elastic fulcrum , which is caused by the continual bottom soil resilience beside the piles and the increase of excavation depths during different steps , is discussed 摘要根据桩锚支护结构的受力和变形特点，研究分析了桩锚支护结构计算模型中支点弹性刚度系数的动态时变性；讨论了随桩内侧坑底土的持续反弹以及不同工况下随著基坑开挖深度的逐渐增大，进而导致弹性支撑刚度系数的减小的变化规律。
