大直径微变形减震桩对岩质高边坡的稳定性影响研究

发布时间：2018-05-10 12:19

本文选题：依山而建 + 微变形减震桩　；参考：《安徽建筑大学》2015年硕士论文

【摘要】：近年来,伴随着我国区域统筹发展战略的不断推进,中西部一些多山地区的城市建设步入了快车道。山区地形多变,地质条件复杂,在这种环境条件中进行工程的建设将面临诸多技术难题。本文正是基于这种背景下以贵阳市标志性建筑—贵阳花果园办公一号楼在施工过程中遇到的技术难题为对象展开的相关研究论述。文中工程位于地形复杂的山区,由于依山而建而受到场地限制,所以在设计时采用了高落差基础设计方案。这个方案采用了把主体结构的一部分基础设置于山顶的方法,由此产生了山顶桩基础在复杂的受力状态下能否保证山顶地基安全的问题。为了解决这个问题在设计中采用了减震桩技术,该技术利用转移力的作用路径和阻尼隔震的方法减轻地震荷载下上部结构对作为地基的岩质边坡稳定性的不利影响。为了对这种技术的原理和作用机制有更深入的理解,本文将从理论研究和工程实测两方面入手对其进行相关研究。在理论分析方面,本文在总结已有研究成果的基础上结合工程实际情况对减震桩受力性能和岩质边坡稳定性的相关理论进行了研究分析。减震桩设计时考虑到地震发生时要求降低其对岩质边坡稳定影响的目的,采取了利用其竖向承载能力而降低其水平承载能力的方法,这与普通混凝土灌注桩的承载性能有所不同,因此文中对减震桩的水平、竖向承载性能以及岩质边坡的稳定理论进行了论述。对于减震桩的减震作用研究,文中建立了上部主体结构-减震桩-岩质边坡的有限元模型,模拟了在上部主体结构自重荷载和地震荷载两种受荷状况下结构体中减震桩与岩质边坡地基之间的相互作用机理,并对减震桩与岩质边坡之间的动力相互作用进行了阐述。在工程实测分析方面,通过对减震桩的受力性能监测和岩质边坡变形的监测,分析了结构自重荷载下减震桩的受力性能和岩质边坡的变形特征。通过本文对微变形减震桩力学性能和岩质边坡稳定性计算方法的研究得出了以下结论:减震桩发挥的承载性能与端承型混凝土灌注桩较为相似,减震桩主要承受竖向荷载而对水平荷载的承担较小,地震荷载下主体结构产生的水平力主要传至抗剪桩来承担;根据已有的桩基承载力计算和岩质边坡稳定性研究成果,对减震桩的水平、竖向承载力计算方法进行了论述,对水平地震荷载下判断岩质边坡稳定的动力安全系数计算方法进行了阐述。通过对花果园办公一号楼工程减震桩受力、岩质边坡变形的监测和有限元数值模型的计算分析,对水平地震荷载作用下微变形减震桩在保障岩质高边坡稳定性方面发挥的效果进行了量的推导。将这些结论应用到工程实践中可以为减震桩设计和施工提供相应的理论参考,对同类工程基础施工采用减震桩技术时的边坡稳定性判断提供一种可以借鉴的方法。
[Abstract]:In recent years, with the continuous promotion of regional overall development strategy, urban construction in some mountainous areas in the central and western regions has entered the fast lane. The terrain of mountainous area is changeable and the geological condition is complex, so the construction of engineering in this environment will face many technical problems. This paper is based on the background of Guiyang landmark building-Guiyang flower orchard office building in the construction process of the technical difficulties encountered as the object of the relevant research. The project is located in the mountainous area with complicated terrain and is limited by the site because of its construction, so the design scheme of the high drop foundation is adopted in the design. This scheme adopts the method of setting a part of the foundation of the main structure on the top of the mountain, which leads to the problem of whether the pile foundation of the top of the mountain can guarantee the safety of the foundation of the top of the mountain under the complicated stress condition. In order to solve this problem, the shock absorption pile technique is adopted in the design, which uses the path of transfer force and the method of damping isolation to reduce the adverse effect of superstructure on the stability of rock slope as foundation under earthquake load. In order to have a deeper understanding of the principle and mechanism of this technique, this paper will study it from two aspects: theoretical research and engineering measurement. In terms of theoretical analysis, based on the summary of existing research results, combined with the actual engineering situation, this paper studies and analyzes the relevant theory of the bearing behavior of the pile and the stability of rock slope. In order to reduce the influence of earthquake on the stability of rock slope, the method of reducing the horizontal bearing capacity by using its vertical bearing capacity is adopted in the design of damping pile. This is different from the bearing capacity of ordinary concrete cast-in-place pile, so the level, vertical bearing capacity and stability theory of rock slope are discussed in this paper. In this paper, the finite element model of the superstructure, the damping pile and the rock slope is established. In this paper, the interaction mechanism between the pile and the foundation of rock slope is simulated, and the dynamic interaction between the pile and the rock slope is described. In the aspect of engineering measurement and analysis, the mechanical behavior of the pile and the deformation characteristics of the rock slope are analyzed by monitoring the mechanical behavior of the pile and the deformation of the rock slope under the self-weight load of the structure. In this paper, the mechanical properties of micro-deformation pile and the calculation method of rock slope stability are studied. The following conclusions are drawn: the bearing capacity of the anti-shock pile is similar to that of the end-bearing concrete cast-in-place pile. Shock absorption pile mainly bears vertical load but bears little horizontal load, the horizontal force generated by main structure under earthquake load is mainly transferred to shear pile, and according to the existing research results of pile foundation bearing capacity and stability of rock slope, the earthquake absorber pile is mainly subjected to vertical load, and the horizontal force generated by the main structure under earthquake load is mainly transferred to shear pile. The calculation method of horizontal and vertical bearing capacity of pile is discussed, and the calculation method of dynamic safety factor for judging the stability of rock slope under horizontal earthquake load is expounded. Through monitoring the deformation of rock slope and calculating and analyzing the finite element numerical model, the stress of the pile and the deformation of rock slope are analyzed. In this paper, the effect of microdeformed pile on the stability of high rock slope under horizontal earthquake load is derived. The application of these conclusions to engineering practice can provide a theoretical reference for the design and construction of shock absorber piles, and provide a reference method for judging slope stability in the construction of similar engineering foundations using shock absorbing pile technology.
【学位授予单位】：安徽建筑大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TU457

【参考文献】