基于钢管混凝土桩的海上风电基础受力性能研究

发布时间：2018-09-13 12:35

【摘要】：风力发电基础是风力发电的重要组成部分,它承担着上部结构所承受的全部荷载与作用,使其能够安全的传递到地基,并要保持整个结构的稳定性。随着风机塔筒高度逐渐的增加,风机型号的加大,使得风电基础受力越来越复杂,而且,风机基础的结构设计技术还不够成熟,使得导致风机整体倾覆、倒塌的事件时有发生,所以,对风电基础进行详细的受力特征分析与优化设计研究是很有必要的。本文提出了一种风电基础—钢管混凝土桩基础,通过对其理论分析,数值计算与软件模拟,完成的主要工作如下：介绍了近海风电结构基础的主要类型,分析了每种基础类型的优缺点,提出以钢管混凝土桩作为近海风电塔筒的桩基础。通过对单桩与土之间的相互作用机理,给出了曲线、分段线性及直线型剪应力模型,提出了单桩的荷载与位移计算公式。考虑到桩在受荷载过程中的桩身变形,给出了不同桩型的桩身压缩系数与桩身压缩量的计算公式。分析了承台下的群桩与土之间的相互作用,分别研究了方形承台与圆形承台下桩与土的荷载传递关系,建立了桩与周围土的变形量计算公式,桩影响半径的计算公式。以实际算例,计算分析了钢管混凝土的抗拉、抗压的承载力,并与实际受力情况进行了对比,得到桩的影响半径,群桩与土的沉降量,验算了承台的抗冲切、抗倾覆及抗滑的安全性。利用ABAQUS有限元软件,分析了钢管混凝土桩基础的整体受力、变形及应力分布。重点分析了受力最大的两个桩的应力沿路径的变化,以及桩与土体变形最大一点的受拉、受压状态。
[Abstract]:Wind power generation foundation is an important part of wind power generation. It bears all the loads and functions of the superstructure, so that it can be safely transferred to the foundation, and the stability of the whole structure should be maintained. With the gradual increase of the height of the fan tower and the increase of the fan type, the force on the wind power foundation is becoming more and more complicated. Moreover, the structural design technology of the fan foundation is not mature enough, which causes the fan to overturn and collapse from time to time. Therefore, it is necessary to analyze the stress characteristics and optimize the design of wind power foundation in detail. In this paper, a kind of wind power foundation, concrete-filled steel tube (CFST) pile foundation, is proposed. Through theoretical analysis, numerical calculation and software simulation, the main work accomplished is as follows: the main types of offshore wind power structure foundation are introduced. The advantages and disadvantages of each foundation type are analyzed, and the concrete filled steel tube pile is proposed as the pile foundation of offshore wind power tower. Through the interaction mechanism between single pile and soil, the curve, piecewise linear and linear shear stress models are given, and the calculation formulas of load and displacement of single pile are presented. Considering the deformation of pile body in the course of loading, the formulas for calculating the compressibility coefficient of pile body and the compression quantity of pile body of different types of piles are given. The interaction between pile group and soil under pile cap is analyzed. The load transfer relationship between pile and soil under square cap and round cap is studied respectively. The formula for calculating the deformation of pile and surrounding soil and the formula for calculating the influence radius of pile are established. The bearing capacity of concrete filled steel tube (CFST) under tension and compression is calculated and analyzed with practical examples. The influence radius of pile, the settlement of pile group and soil are obtained, and the impact shear of pile cap is checked and calculated. Anti-capsizing and anti-skid safety. The stress, deformation and stress distribution of CFST pile foundation are analyzed by ABAQUS finite element software. The stress variation along the path of the two piles with the greatest force is analyzed, and the tension and compression state of the maximum deformation of the pile and the soil is also analyzed.
【学位授予单位】：东北大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TU476;TM614

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