基坑复合土钉支护可靠度研究

发布时间：2018-06-11 13:50

本文选题：复合土钉支护 + 数值模拟　；参考：《中国石油大学（华东）》2013年硕士论文

【摘要】：复合土钉支护是近年来在土钉支护形式的基础上发展起来的新型支护结构。它根据具体的工程条件，将土钉支护与深层搅拌桩、旋喷桩、微型桩、钢管或预应力锚杆等结构结合起来，形成一种复合基坑支护技术，该技术克服了传统土钉支护技术不能控制边坡变形的缺陷，具有安全可靠、造价低、工期短、使用范围广等特点，获得了越来越广泛的工程应用。因此，开展对复合土钉支护技术的稳定性和可靠度的研究是十分有必要的。本文主要是基于青岛火车站站房基坑支护工程，分析工程中的复合土钉支护的稳定性，并且计算其可靠度指标。主要内容如下：运用FLAC3D模拟本工程中复合土钉支护，确定各种软件运行中所需要的参数。模拟基坑开挖的过程，，研究土体与锚杆、土钉的相接，预应力的施加等。基于实例，探讨在不同工程情况下复合土钉支护对土体变形的影响。经过类比有差异的工程情况下所产生的变形，可以看出复合土钉支护对施工过程中的变形可以有良好的压制效果。通过计算，分别探讨预应力锚杆以及土钉的轴力，绘制其变化曲线，得出规律。探讨基坑的稳定性随着复合土钉支护体系的参数发生变化时而产生的效应。讨论其作用的原理，并为实际工程的设计提供建议。编制了基于遗传算法的Matlab计算程序，计算青岛火车站站房改造工程基坑复合土钉支护体系的可靠度，并对预应力锚杆、土钉的设计参数进行变化，分别计算对应的可靠度指标，得出可靠度指标随参数变化的产生的变化规律。
[Abstract]:Composite soil nailing is a new type of support structure developed on the basis of soil nailing in recent years. According to the specific engineering conditions, it combines soil nailing support with deep mixing pile, rotary jet pile, micro pile, steel pipe or prestressed anchor to form a composite foundation pit supporting technology. This technique overcomes the defects that the traditional soil nailing support technology can not control the slope deformation, and has the characteristics of safety and reliability, low cost, short time limit and wide range of application, so it has been more and more widely used in engineering. Therefore, it is necessary to study the stability and reliability of composite soil nailing. The reliability index is calculated. The main contents are as follows: FLAC3D is used to simulate the composite soil nailing support in this project and the parameters needed in the operation of various software are determined. In order to simulate the excavation process of foundation pit, the connection of soil and anchor rod, soil nailing and the application of prestress are studied. Based on an example, the influence of composite soil nailing on soil deformation is discussed in different engineering conditions. By analogy with the deformation under the different engineering conditions, it can be seen that the composite soil nailing support can have a good suppression effect on the deformation in the construction process. Through calculation, the axial force of prestressed anchor rod and soil nailing is discussed, and its changing curve is drawn. The effect of the stability of foundation pit with the change of the parameters of composite soil nailing support system is discussed. The principle of its action is discussed, and some suggestions are provided for the design of practical engineering. A Matlab program based on genetic algorithm is developed to calculate the reliability of the composite soil nailing support system of the foundation pit in the reconstruction project of the station house of Qingdao Railway Station. The design parameters of the prestressed anchor rod and soil nailing are changed and the corresponding reliability indexes are calculated respectively. The variation law of reliability index with parameter change is obtained.
【学位授予单位】：中国石油大学（华东）
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU476

【参考文献】