考虑土塞效应的群桩竖向动力特性研究
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摘 要
随着海上风电场、海上石油平台、跨海大桥等近海工程的建设，群桩基础作为
一种经济而有效的基础形式，被广泛的应用到这些工程中。管桩打入土层中会在管
桩底部形成土塞，土塞对于管桩的竖向承载力影响较为明显，对于管桩竖向振动特
性的影响不可忽略。因此，对于竖向荷载作用下，群桩的动力特性研究显得尤为重
要。本文对考虑土塞效应的群桩竖向动力特性进行了如下的研究：
（1）研究了土塞形成的机理和性状，分析了土塞形成的原因并对土塞率进行
明确的定义。回顾总结了土塞闭塞程度的理论判断方法，重点总结了山原法的判断
步骤，为土塞闭塞程度的判别提供了理论依据。
（2）首先假定桩周土体为线弹性，将成层地基中的管桩看作 Winkler 地基上
的梁，并采用传递矩阵法来考虑土体的分层情况，建立了考虑土塞效应的单桩竖向
振动模型，推导出考虑土塞效应的管桩竖向振动阻抗函数，并通过与经典解的对比，
验证本文解的合理性，进而分析管桩材料、长径比、泊松比、阻尼比、桩土相对刚
度及土层相对刚度六个因素对单桩阻抗的影响。
（3）建立考虑土塞桩-桩竖向动力相互作用因子的模型，推导出考虑土塞效应
的桩-桩竖向动力相互作用因子函数，并通过与经典解的对比，验证本文解的合理
性，据此分析桩间距、长径比、泊松比、阻尼比、桩土相对刚度及土层相对刚度六
个因素对桩-桩竖向动力相互作用因子的影响。
（4）建立了考虑土塞效应的群桩动力分析模型，推导了考虑土塞效应的群桩
阻抗的计算方法，并通过与经典解的对比，验证本文解的准确性。继而分析桩间距、
长径比、泊松比、阻尼比、桩土相对刚度、土层相对刚度和布桩形式七个因素对群
桩阻抗的影响。同时，推导了考虑土塞效应的群桩桩身动内力，并详细讨论不同布
桩形式对于桩身动内力的影响。
（5）最后将前面得到的模型应用到了东海大桥海上风电场风机基础上，分析
了竖向荷载作用下考虑土塞效应的东海大桥风电群桩基础的动力响应，为工程设
计提供参考。
关键词：土塞效应 竖向振动 桩-桩竖向动力相互作用因子 群桩阻抗
群桩动内力
ABSTRACT
As an economic beneficial and effective style of foundation, piles foundation has
been widely used in offshore constructions like offshore wind farm, offshore oil platform
and cross sea bridge. When punching pipe pile into the soil the soil plug will be formed.
The soil plug has a significant influence on the vertical vibration feature of pipe pile. It
makes the study of soil plug, especially the dynamic characteristics under vertical load,
very meaningful both in theory and practice. Some subjects of the dynamic features of
pipe pile under vertical load are investigated as following：
(1)The causes of the emergence of soil plug and a clear soil plug rate are identified
based on the study of the mechanism of the formation of soil plug and its traits. The
theoretical methods of identifying soil plug are summarized, focusing on the Shanyuan
Method. The theoretical basis for distinguishing the degree of soil plug is provided.
(2)Assuming that the soil around the pipe was elastic-nonlinear, the pipe pile in
layered foundation is regarded as the beam on Winkler foundation and the transfer matrix
method is adopted to consider the soil layer. According to the elastic beam axial vibration
theory the vertical vibration of pile impedance function is deduced. By comparing with
the reduced solution, the solution got in this paper is proved reasonable. Furthermore the
influence of material of pipe pile, length-diameter ratio, poisson ratio, damping ratio, the
relative stiffness of pile-soil and soil relative stiffness on the impedance of single pipe
pile are assessed.
(3)A pile-pile vertical dynamic interaction model considering soil plug effect is
established. Based on that the function of pile-pile vertical dynamic interaction
considering soil plug effect is deduced. Furthermore the influence of distance between
piles, length-diameter ratio, poisson ratio, damping ratio, relative stiffness of pile-soil and
soil relative stiffness on pile-pile vertical dynamic interaction are assessed.
(4) A pile-pile dynamic analysis model considering soil plug effect is established.
The calculation method of pile impedance considering soil plug effect is deduced. By
comparing with the reduced solution, the solution got in this paper is proved reasonable.
Furthermore the influence of distance between piles, the length-diameter ratio, poisson
ratio, damping ratio and the relative stiffness of piles-soil, the soil relative stiffness and
the arrangement of piles on the impedance of piles. At the same time, dynamic internal
force of group piles considering soil plug effect is deduced. And influence of different
layout of piles on pile body dynamic internal forces is discussed in detail.
(5)Applying the model got in last chapter to the Donghai Bridge offshore wind farm,
analysis the dynamic response of Donghai Bridge wind power group pile foundation
considering soil plugging effect under the action of vertical load, which provide a
reference for engineering design.
Key words: soil plug effect, vertical vibration, pile-pile vertical
dynamic interaction factor, pile groups impedance, the internal
force of pile groups
目 录
摘 要
ABSTRACT
第一章 绪 论 ................................................................................................................ 1
1.1 研究背景 ........................................................................................................... 1
1.2 关于考虑土塞效应的桩的动、静力特性的国内外研究现状 ....................... 1
1.2.1 考虑土塞效应的桩的静力特性研究现状 ............................................ 1
1.2.2 考虑土塞效应的桩的动力特性研究现状 ............................................ 4
1.3 桩基振动分析研究现状 ................................................................................... 5
1.3.1 连续介质解析理论 ................................................................................ 5
1.3.2 Winkler 地基梁理论 ............................................................................... 6
1.3.3 数值分析理论 ........................................................................................ 7
1.4 本文研究内容 ................................................................................................... 8
第二章 土塞效应 .......................................................................................................... 10
2.1 土塞形成的机理和性状 ................................................................................. 10
2.2 土塞参数 ......................................................................................................... 10
2.2.1 土塞高度 .............................................................................................. 10
2.2.2 土塞率 ................................................................................................... 11
2.3 土塞闭塞程度判别 .......................................................................................... 11
2.3.1 土塞闭塞程度 ....................................................................................... 11
2.3.2 闭塞效果的理论判断方法 ................................................................... 11
2.4 影响土塞性状的因素 ..................................................................................... 14
2.5 土塞的力学机理 ............................................................................................. 14
2.6 本章小结 ......................................................................................................... 15
第三章 考虑土塞效应的单桩竖向动力特性 .............................................................. 16
3.1 管桩竖向振动模型研究阻抗计算 ................................................................. 16
3.1.1 管桩土塞模型 ...................................................................................... 16
3.1.2 桩底边界条件 ...................................................................................... 19
3.2 单桩阻抗验证 ................................................................................................. 20
3.3 单桩阻抗影响因素分析 ................................................................................. 20
3.3.1 管桩材料 .............................................................................................. 20
3.3.2 长径比 .................................................................................................. 22
3.3.3 泊松比 .................................................................................................. 23
3.3.4 阻尼比 .................................................................................................. 25
3.3.5 桩土相对刚度 ...................................................................................... 27
3.3.6 土层相对刚度 ...................................................................................... 28
3.4 本章小结 ......................................................................................................... 31
第四章 考虑土塞效应的桩-桩竖向动力相互作用因子 ............................................. 32
4.1 考虑土塞效应的桩-桩竖向动力相互作用因子模型 .................................... 32
4.2 桩-桩竖向动力相互作用因子验证 ................................................................ 34
4.3 桩-桩竖向动力相互作用因子影响因素分析 ................................................ 36
4.3.1 桩间距 .................................................................................................. 36
4.3.2 长径比 .................................................................................................. 38
4.3.3 泊松比 .................................................................................................. 40
4.3.4 阻尼比 .................................................................................................. 42
4.3.5 桩土相对刚度 ...................................................................................... 44
4.3.6 土层相对刚度 ...................................................................................... 46
4.4 不同土塞高度对于桩-桩竖向动力相互作用因子的影响分析 .................... 50
4.5 本章小结 ......................................................................................................... 51
第五章 考虑土塞效应的群桩竖向动力阻抗 .............................................................. 53
5.1 考虑土塞效应的群桩竖向动力阻抗计算方法 ............................................. 53
5.2 群桩竖向动力阻抗验证 ................................................................................. 54
5.3 考虑土塞效应的群桩竖向动力阻抗影响因素分析 ..................................... 55
5.3.1 桩间距 .................................................................................................. 55
5.3.2 长径比 .................................................................................................. 57
5.3.3 泊松比 .................................................................................................. 59
5.3.4 阻尼比 .................................................................................................. 60
5.3.5 桩土相对刚度 ...................................................................................... 61
5.3.6 土层相对刚度 ...................................................................................... 63
5.3.7 布桩形式 .............................................................................................. 65
5.4 不同土塞高度对于群桩竖向动力阻抗的影响分析 ..................................... 67
5.5 本章小结 ......................................................................................................... 69
第六章 考虑土塞效应的群桩桩身动内力 .................................................................. 71
6.1 考虑土塞效应的桩身动内力的计算方法 ..................................................... 71
6.2 桩身动内力验证 ............................................................................................. 72
6.3 布桩形式对桩身动内力影响 ......................................................................... 73
6.3.1 2×1 群桩 ................................................................................................ 73
6.3.2 2×2 群桩 ................................................................................................ 74
6.3.3 3×3 群桩 ................................................................................................ 74
6.3.4 6×1 群桩 ................................................................................................ 75
6.4 本章小结 ......................................................................................................... 76
第七章 工程算例 .......................................................................................................... 77
7.1 工程概况 ......................................................................................................... 77
7.2 考虑土塞效应的群桩竖向动力相互作用因子 ............................................. 78
7.3 考虑土塞效应的群桩竖向动力阻抗 ............................................................. 79
7.4 本章小结 ......................................................................................................... 79
第八章 结论与展望 ...................................................................................................... 80
8.1 结论 ................................................................................................................. 80
8.2 展望 ................................................................................................................. 82
参考文献 ........................................................................................................................ 83
在读期间公开发表的论文和承担科研项目及取得成果 ............................................ 89
致 谢 ............................................................................................................................ 90
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作者：侯斌
分类：高等教育资料
价格：15积分
属性：95 页
大小：7.8MB
格式：PDF
时间：2025-01-09
