水平荷载作用下单桩受力性能的有限元模拟分析

发布时间：2018-08-25 10:24

【摘要】：桩基础在建设工程中广泛使用,使得考虑桩基的水平承载力成为一种不可避免的趋势。在某些工程中,水平荷载甚至已经成为桩基础设计的主要控制因素。相比竖向荷载作用下桩基承载力的研究,水平荷载作用下桩基的分析研究就显得相对落后,尤其是动力荷载作用下桩基础响应的研究就显得更加的不足。此外,桩基的现场水平荷载实验由于其成本高、操作复杂而在工程应用中受到限制。因此,将数值模拟运用于桩基受力过程中桩、土体的内力和变形分析具有一定的理论意义和实际应用价值。本文在检索国内外研究成果并进行系统分析的基础上,采用理论分析和数值模拟相结合的研究方法对水平静力荷载和动力荷载作用下桩基的受力性能进行了分析,利用有限元软件模拟分析了荷载、土层、桩径和桩长的变化对桩基的影响以及在不同形式的动力荷载作用下桩基响应。论文的主要工作和取得的成果如下： (1)利用(?)ABAQUS有限元软件建立桩-土模型和桩-弹簧模型分别对试桩资料进行模拟分析,并与m法计算结果和实测资料进行对比,分析有限元模拟存在的误差及产生原因。 (2)依次对荷载、土层、桩径、桩长做出规律性的变化,以得到桩身位移、桩身弯矩、桩身剪力等响应,并将模拟结果与m法计算结果进行对比,得到了荷载、土层、桩径、桩长对桩基的影响规律。对有限元模拟所得数据进行拟合,分析了拟合误差。 (3)利用ABAQUS建立了桩-弹簧模型,并与m法、桩-土模型计算结果进行对比,分析了桩-弹簧模型的优点及不足,研究了桩身位移、桩身弯矩、桩身剪力随弹簧刚度的变化规律,进行了数据的拟合,分析了拟合误差。 (4)模拟了在突加长期荷载、正弦荷载、冲击荷载、地震荷载作用下桩基的响应,分析了不同的荷载作用形式对桩基内力的影响及规律。 (5)模拟分析在地震荷载作用下,土层、桩径、桩长的变化导致桩身的不同响应。并对不同情况下的桩身响应进行了对比分析。 (6)对比分析静荷载和动荷载作用下土层、桩径、桩长对桩基内力的不同响应。
[Abstract]:Pile foundation is widely used in construction projects, which makes it an inevitable trend to consider the horizontal bearing capacity of pile foundation. In some projects, horizontal load has even become the main control factor of pile foundation design. Compared with the research of pile foundation bearing capacity under vertical load, the research of pile foundation analysis under horizontal load is relatively backward, especially the research of pile foundation response under dynamic load is more insufficient. In addition, the field horizontal load test of pile foundation is limited in engineering application due to its high cost and complex operation. Therefore, it is of theoretical significance and practical application value to apply numerical simulation to the analysis of the internal force and deformation of the soil in the course of pile foundation loading. On the basis of searching domestic and foreign research results and systematic analysis, this paper analyzes the mechanical behavior of pile foundation under horizontal static load and dynamic load by combining theoretical analysis and numerical simulation. The influence of load, soil layer, pile diameter and pile length on pile foundation and the response of pile foundation under different forms of dynamic load are simulated by finite element software. The main work and achievements are as follows: (1) the pile-soil model and pile-spring model are established by using ABAQUS finite element software, and the results are compared with the calculated results of m method and the measured data. The errors in finite element simulation are analyzed and the causes are analyzed. (2) regularly changing the load, soil layer, pile diameter and pile length in order to obtain the responses of pile displacement, pile bending moment, pile shearing force and so on. The influence of load, soil layer, pile diameter and pile length on the pile foundation is obtained by comparing the simulation results with the results of m method. The data obtained from finite element simulation are fitted, and the fitting error is analyzed. (3) the pile-spring model is established by using ABAQUS, and compared with the results of m method and pile-soil model, the advantages and disadvantages of pile-spring model are analyzed. The variation law of pile displacement, pile bending moment, pile shear force with spring stiffness is studied, and the fitting error is analyzed. (4) the long-term load, sinusoidal load, impact load are simulated. The response of pile foundation under earthquake load is analyzed, and the influence and regularity of different load forms on the internal force of pile foundation are analyzed. (5) under earthquake load, the variation of soil layer, pile diameter and pile length leads to different responses of pile body. The responses of pile body under different conditions are compared. (6) the different responses of soil layer, diameter and length of pile to the internal force of pile foundation under static and dynamic loads are analyzed.
【学位授予单位】：昆明理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU473.1

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