超前微桩复合土钉支护稳定及变形简化计算方法

发布时间：2018-06-22 15:43

本文选题：超前微桩 + 复合土钉支护　；参考：《工程力学》2014年03期

【摘要】：超前微桩复合土钉支护是一种经济有效的基坑支护形式,但对其设计分析方法的研究远落后于工程实践。该文在对此种复合土钉支护的构造及工作性能进行简要分析的基础上,对其整体稳定验算方法和变形计算方法进行讨论,借鉴已有的一些相关研究提出了相应的简化计算方法。针对其整体稳定验算,提出考虑微桩-土相对刚度采用不大于2.5倍特征长度上土体被动抗力来考虑微桩作用的建议,从而给出一种较为简便的整体稳定验算方法,就一些实际工程的计算对比表明所建议的方法合理可行。针对其坑壁位移计算,在仔细分析此种支护体系受力变形机理的基础上,基于基坑支护计算的增量法及弹性地基梁求解的链杆法,提出一种思路清晰的简化计算方法,给出了具体的计算模型、参数确定方法及问题求解方法,并通过与有限元计算及工程实测的对比对所提出的方法进行了检验。
[Abstract]:The composite soil nailing support of advanced micro-pile is an economical and effective form of foundation pit support, but the research on its design and analysis method lags far behind the engineering practice. Based on a brief analysis of the structure and working performance of the composite soil nailing support, this paper discusses its overall stability checking method and deformation calculation method, and puts forward corresponding simplified calculation methods for reference to some related studies. Considering the relative stiffness of micro-pile and soil, the paper proposes that the passive resistance of soil not more than 2.5 times the characteristic length should be taken into account in order to consider the action of micro-pile, and a simple method of overall stability checking is given. The comparison of some practical projects shows that the proposed method is reasonable and feasible. According to the calculation of the displacement of the pit wall, based on the careful analysis of the mechanism of stress and deformation of the supporting system, a simplified calculation method is proposed based on the incremental method of foundation pit support calculation and the chain bar method for solving the elastic foundation beam. The concrete calculation model, parameter determination method and problem solving method are given, and compared with finite element calculation and engineering measurement, the proposed method is tested.
【作者单位】：清华大学土木工程系;土木工程安全与耐久教育部重点实验室;电力规划设计总院;
【基金】：国家支撑计划项目(2008BAJ06B01-5)
【分类号】：TU476

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