钢塑复合拉筋带-模块式面板挡土墙参数反演及稳定性分析

发布时间：2018-02-14 03:59

本文关键词： 加筋土挡土墙变形监测稳定性评价粒子群算法最小二乘支持向量机变形预测　出处：《山东大学》2017年硕士论文　论文类型：学位论文

【摘要】：加筋土挡土墙因其占地少、施工简便、造价低廉、结构协调变形能力强、造型美观等诸多优点在国内外得到迅速发展,加筋技术在我国已经有上千年的历史,最近几十年国内更是兴建了大量加筋土挡土墙工程。但加筋土挡土墙由于其受力体系的复杂性,往往在其建成3到5年后会产生不同程度的变形和破坏,进一步的变形甚至会导致挡土墙失稳。目前对于加筋土挡土墙的理论研究远远落后于工程实践,众所周知加筋土挡土墙由面板系统、筋材、填土三部分组成,但是目前对于加筋土挡土墙各部分的工作机制和相互影响机理尚不清楚,尤其对于服役期加筋土挡土墙,其稳定性评价目前尚无明确的标准,变形预测方面的研究也较少。本文基于济菏高速某加筋土挡土墙工程的现场变形监测资料,结合现场取芯后室内土工试验、有限元数值计算等技术手段,综合分析评价了服役期加筋土挡土墙的稳定性。通过室内土工试验、筋材试验及有限元数值计算分析了对服役期加筋土挡土墙变形及稳定性起重要影响的关键力学参数。将粒子群算法和最小二乘支持向量机(PSO-LSSVM)模型应用到加筋土挡土墙关键力学参数反演中。最后,给出了服役期加筋土挡土墙变形预测的方法。通过对加筋土挡土墙现场监测资料的分析整理、现场取芯及相关室内试验结果和位移反分析的研究,主要得出以下结论:(1)对于本加筋土挡土墙不同变形程度断面处其填土含水率存在较大差别,侧向变形较大断面处其含水率较高。(2)对于本加筋土挡土墙,影响其侧向变形的主要因素是填土内摩擦角φ和筋材轴向刚度Ej,而在填土含水率达到平衡含水率后其填土内摩擦角φ可认为稳定不变,加筋土挡土墙在此基础上的进一步变形主要是受筋带蠕变的影响。(3)对于服役期加筋土挡土墙,可以通过侧向位移量/墙高值及筋带应变量两个指标评价其稳定状态,其中侧向位移量/墙高值可以通过现场监测得到,筋带应变量可以通过有限元计算得到并与相关设计指标进行对比。(4)将PSO-LSSVM这一通用反分析模型应用到加筋土挡土墙位移反分析中,可以得到不错的结果,基于反演参数的变形预测值与现场实测位移结果比较吻合,具有一定的工程参考价值。
[Abstract]:The reinforced soil retaining wall because of its small, simple construction, low cost, structure coordination deformation ability, the advantages of beautiful appearance, has been developing rapidly at home and abroad, reinforcement technology has been around for thousands of years in China, in recent decades China is the construction of a large number of reinforced earth retaining wall engineering. But the reinforced soil retaining wall due to its complexity of the system, often in the completion of the 3 to 5 years will produce deformation and damage in different degree, and even lead to instability of the retaining wall deformation. Further the theoretical research on the reinforced earth retaining wall is far behind the engineering practice of reinforced retaining, as everyone knows the wall panel system, reinforcement, three parts fill, but the reinforced retaining wall and the work mechanism of the mutual influence mechanism is not clear, especially for the service period of reinforced earth retaining wall, there is no stability evaluation Clear criteria of deformation prediction study is less. In this paper, a Jinan Heze Expressway reinforced retaining wall engineering field based on the deformation monitoring data, combined with the indoor soil test coring technology, finite element numerical calculation, comprehensive analysis and evaluation of the stability of the service period of reinforced earth retaining wall with soil. Test, calculation and analysis of service life of reinforced retaining wall deformation and stability of the key mechanical parameters play an important influence. The reinforcement test and finite element numerical particle swarm algorithm and least squares support vector machine (PSO-LSSVM) model to the reinforced soil retaining wall key mechanical parameters inversion. Finally, gives the service period reinforced retaining wall deformation prediction method. Through the analysis of reinforced retaining wall field monitoring data collection, the research on back analysis of core and related laboratory test results and the displacement field, the Lord will be The following conclusions: (1) for the reinforced soil retaining wall in different section of the deformation degree of soil moisture rate difference of the lateral deformation of large section of the high water content. (2) for the reinforced earth retaining wall, the influence factors of lateral deformation is internal friction angle stiffness Ej and the reinforcement in the axial direction, filling water content reaches the equilibrium moisture content of the soil internal friction angle can be considered stable, reinforced retaining wall on the basis of further deformation is mainly affected by reinforcement creep. (3) for the service period of the reinforced earth retaining wall by lateral displacement the wall / higher and reinforcement strain two indicators to evaluate the stable state, the lateral displacement of the wall / high value can be obtained by field monitoring, reinforcement strain can be obtained by the finite element method and compared with the design index. (4) the PSO-LSSVM of the general anti The analytical model is applied to the displacement back analysis of reinforced earth retaining wall, and good results can be obtained. The predicted values based on the inversion parameters coincide well with the measured displacement results in the field, which has certain engineering reference value.

【学位授予单位】：山东大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU476.4

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