【作者】 黄俊；

【导师】 陈静曦；

【作者基本信息】 武汉理工大学 ， 采矿工程， 2006， 硕士

【摘要】 论文主要对复合土钉支护稳定性及应用情况进行相关研究。基于复合土钉支护技术国内外应用和研究情况,介绍了复合土钉支护技术的国内外应用和研究现状、发展动态。本文在前人研究的基础上,建立了非线性有限元计算模型,通过非线性有限元模拟计算结果,结合武汉地区实际工程实测资料,分析总结了复合土钉墙受力变形特征及承载机理。主要进行了以下研究工作: (1) 概括复合土钉墙的组成、构造形式,同时对其主要构造形式的工程特性以及复合土钉墙的施工方法和工艺特点进行了分析。 (2) 将正交试验法引入基坑工程分析,研究了11种因素对搅拌桩-土钉复合支护稳定状态的敏感性,得到了各因素对支护结构稳定性的影响规律。这11个因素分别为:土钉长度、基坑深度、土钉界面摩擦力、土钉下倾角、土钉水平间距、土钉排数、土体重度、内摩擦角、粘聚力、坡顶超载、搅拌桩插入深度。 (3) 针对复合土钉墙的构造特点,建立非线性有限元计算模型;其中包括对土体、面层及搅拌桩超前支护、土钉、接触面单元的模拟。 (4) 依据工程实测资料,分别对地层条件相差较大的区域采用非线性有限元法进行数值模拟分析,研究复合土钉墙在施工过程中的变形特征、内力变化、破坏区的发展规律,总结其承载机理。发现地层条件对复合土钉墙的受力变形及承载机理影响较大;在地层软弱的地区复合土钉墙侧向位移上、下部较小,中下部较大,呈“凸肚状”;墙后地面沉降量的最大点在荷载中部,在外观上呈现出“沉降槽”。在地层较好的区域复合土钉墙侧向位移在上部大,下部小,呈绕趾向外转动的“前倾状”;墙后最大沉降量的点在搅拌桩顶,向后依次递减,呈“斜坡状”。 (5) 根据实测资料和有限元分析计算结果,本文系统的总结了复合土钉墙在不同地质条件下的受力变形特征和承载机理,为今后该支护技术的推广和发展提供理论依据。根据分析计算结果,结合现场工程施工经验,对复合土钉墙支护体系设计和施工提出了几点建议。更多还原

【Abstract】 In this paper, the applications and the stability analysis of compound soil nailing were studied. Based on the fact of the applications and the researches on compound soil nailing in land and overseas, it were introduced that the applications and the researches on compound soil nailing in land and overseas nowadays. Based on the formers’ results, this paper has established non-linear FEW calculation modes. According to the results of non-linear FEW and the data of field in Wuhan, this paper summarized the bearing and deformation mechanic of the composite soil-nailed wall. The main researches are as follows:1. Review the composition and the constructions analyze its engineering characteristics of the main of form construction, its method and techniques characteristic.2. The orthogonal experiment method is applied in the analysis of foundation ditch, studied 11 factors to the mixing pile-soil — soil nailing supporting of the sensibility of stable states, got all of the factors on the influence rule of the stability of supporting structure. These 11 factors, which respectively are including: length of soil nailing, insert deepness of piles, friction force of soil nailing interface, declination angle of soil nailing, horizontal spacing of soil nailing, rows of soil nailing, unit weight of soil, friction angle, unit cohesion, overload of slope, diameter of soil nailing.3. Aimed at the characteristic of the constructing composite soil-nailed wall, the paper has established non-linear FEM calculation mode, including simulation of soil, mixing pile-soil, soil-nailed, Goodman interface element.4. According to the data of the field measurements, this paper has used non-linear FEM separately in different geology conditions, analyzed deformation characteristics, internal force and extension areas destroyed regulation of the composite soil-nailed wall during the progress of the construction and summarized the bearing and deformation mechanic of the composite soil-nailed wall. Geology conditions have decided the bearing and deformation mechanic of the composite soil-nailed wall. In the loose-soft soil and the area full of underground water, the maximum horizontal displacement is located in middle of the wall, and the maximum vertical displacement is located in the middle of the upside load. In the more strength soil, the maximum horizontal displacement is located in the top of the wall, and the maximum vertical displacement is located in the edge of deep excavation pits, so it looked as "decline slope".5. Based on the data of the field measurements and the calculation’s results, this paper has summarized the bearing and deformation mechanic of the composite soil-nailed wall in the different geology conditions, and this useful research results have provided the theoretic foundation for this technology. According to the calculation’s results and the working skills of the field, this paper has given some beneficial advices on the composite soil-nailed wall’s design and work.更多还原