钢护筒混凝土灌注桩基础抗震承载性能研究
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摘 要
我国大型桥梁中常采用的高桩承台基础通常是地震作用下的薄弱环节，利用
钢护筒参与桩身受力来改善基础的抗震性能，具有高效、简单且又经济的突出特
点。但由于目前尚缺乏具有针对性的理论与试验研究，对钢护筒混凝土灌注桩的
抗震机理尚不清楚，导致了在分析方法以及构造处理上的不统一。本文主要针对
考虑钢护筒效应的桩身承载特性，以及钢护筒与承台不同连接构造形式的抗震性
能等两个方面开展研究。主要研究成果有：
(1) 室内试验针对桩身有粘结和无粘结两种不同工况，桩头节点浅嵌入、锚
筋嵌入和深浅入三种不同工况分别进行试验研究，利用 ABAQUS 软件建立数值
模型，进行验证分析，符合性较好。
(2) 钢护筒-桩身极限承载能力受界面粘结削弱的影响效应相对较小，可以简
化采用钢管混凝土组合截面进行计算，再偏于安全地考虑不小于 0.85的折减系数。
(3) 钢护筒-承台连接节点的承载能力受节点连接形式的影响很大，对不满足
平截面假定的桩头节点形式，承载力计算困难，可以由在平截面假定下计算的抗
弯承载力乘以一个增大系数作为其设计和研究的依据，但增大系数不大于 1.16。
关键词: 高桩承台 钻孔灌注桩 钢护筒 抗震性能 设计方法
ABSTRACT
Pile foundation with high bent cap, as a very popular foundation type used for
many major bridges in China, are actually the most vulnerable component under
seismic actions. Making steel casings participate foundation load bearing to enhanced
its seismic resistance is considered to be a very promising measure for this problem
since it can benefit a lot in construction convenience and also in cost saving. However,
the interaction mechanics between the steel casing and concrete pile is still unclear
because of the lack of special theoretical and experimental researches, and this has
result in disaccord in theoretical hypothesis, analysis models and structural
constructions.This work mainly focus on the bearing characteristics of piles with the
steel tube and seismic performance capacity of joints between steel casing and cushion
cap with various configuration. The main achievements and conclusions are as follows:
(1) Laboratory tests on piles with bonded and unbonded in two different
conditions,and the node of pile head in three different conditions were studied.
Numerical model is established by using ABAQUS software, The analysis results
agreed well.
(2) The reduction of the bending capacity due to the weak bonding property is no
more than 15 percent. Therefore, it can be simply evaluated by the ideal composite
section method with an additional discount coefficient no less than 0.85.
(3) The bearing capacity of the pile-cap joint is greatly influenced by the
connection manner. The node of pile head unsatisfied with the assumption of plane
cross section is difficult to calculate the bearing capacity, may be calculated in the
assumption of plane section of the bending bearing capacity with an increasing
coefficient , as the basis of design and research .But the increasing coefficient is less
than 1.16.
Key words: high-rise pile cap foundation, cast in place pile, steel shell,
seismic performance, designing method
目录
中文摘要
ABSTARCT
第一章 绪 论 .................................................................................................................. 1
1.1 研究背景 ............................................................................................................ 1
1.2 研究现状 ............................................................................................................ 3
1.2.1 桩身的研究现状 ...................................................................................... 3
1.2.2 桩头节点的研究现状 .............................................................................. 4
1.3 存在问题 ............................................................................................................ 5
1.4 研究内容及安排 ................................................................................................ 6
第二章 钢护筒混凝土灌注桩桩身拟静力试验 ............................................................ 7
2.1 实验目的 ............................................................................................................ 7
2.2 实验方法的选择 ................................................................................................ 7
2.3 试验模型设计 .................................................................................................... 7
2.4 试验加载设备与试件安装 ................................................................................ 9
2.4.1 加载设备的选择 ...................................................................................... 9
2.4.2 试架安装 ................................................................................................ 10
2.5 加载制度 .......................................................................................................... 10
2.6 实验观测 ........................................................................................................... 11
2.7 材性试验 ........................................................................................................... 11
2.8 试验现象与破坏状态 ...................................................................................... 13
2.9 实验结果与分析 .............................................................................................. 14
2.9.1 滞回曲线 ................................................................................................ 14
2.9.2 骨架曲线 ................................................................................................ 17
2.9.3 刚度退化 ................................................................................................ 18
2.9.4 延性系数 ................................................................................................ 20
2.9.5 耗能性能 ................................................................................................ 21
2.10 本章小结 ........................................................................................................ 22
第三章 桩身抗弯承载力模拟分析与简化估算 .......................................................... 23
3.1 有限元模型的建立 .......................................................................................... 23
3.1.1 基本构型 ................................................................................................ 23
3.1.2 材料本构 ................................................................................................ 24
3.1.3 粘结界面 ................................................................................................ 28
3.2 数值模型验证与粘结强度影响分析 .............................................................. 29
3.2.1 数值模型验证 ........................................................................................ 29
3.2.2 粘结强度影响分析 ................................................................................ 30
3.2.3 并联构件刚度分配计算方法适用性分析 ............................................ 32
3.2.4 桩身粘结强度对中和轴位置的影响 .................................................... 33
3.3 简化估算方法 .................................................................................................. 34
3.3.1 钢管混凝土计算理论 ............................................................................ 34
3.3.2 等效折减系数 ........................................................................................ 36
3.4 本章小结 .......................................................................................................... 39
第四章 桩头节点拟静力试验 ...................................................................................... 40
4.1 试验目的 .......................................................................................................... 40
4.2 试验方法的选择 .............................................................................................. 40
4.3 模型设计 .......................................................................................................... 40
4.4 实验仪器与安装 .............................................................................................. 42
4.5 加载制度 .......................................................................................................... 43
4.6 试验现象现象与破坏状态 .............................................................................. 43
4.7 实验结果与分析 .............................................................................................. 45
4.7.1 滞回曲线 ................................................................................................ 45
4.7.2 骨架曲线 ................................................................................................ 49
4.7.3 刚度退化 ................................................................................................ 50
4.7.4 延性系数 ................................................................................................ 51
4.7.5 耗能性能 ................................................................................................ 52
4.8 本章小结 .......................................................................................................... 52
第五章 桩头抗弯承载力模拟分析与简化估算 .......................................................... 54
5.1 有限元模型的建立 .......................................................................................... 54
5.1.1 模拟方法的选取 .................................................................................... 54
5.1.2 模型建立 ................................................................................................ 55
5.2 模拟验证与分析 .............................................................................................. 55
5.2.1 破坏状态对比分析 ................................................................................ 56
5.2.2 钢护筒沿 Z轴应力分布的对比分析 .................................................... 57
5.2.3 承载力的对比分析 ................................................................................ 58
5.3 锚筋含量影响分析 .......................................................................................... 60
5.4 简化估算 .......................................................................................................... 61
5.4.1 UCFYBER 软件简介 .............................................................................. 61
5.4.2 分析模型 ................................................................................................ 62
5.4.3 浅嵌入式承载力的简化估算 ................................................................ 62
5.4.4 锚筋嵌入式承载力的简化估算 ............................................................ 63
5.5 本章小结 .......................................................................................................... 64
第六章 结论与展望 ...................................................................................................... 66
6.1 结论 .................................................................................................................. 66
6.2 进一步工作方向 .............................................................................................. 67
参考文献 ........................................................................................................................ 68
在读期间公开发表的论文和承担科研项目及取得成果 ............................................ 71
致 谢 .............................................................................................................................. 72
第一章 绪论
1
第一章 绪 论
1.1 研究背景
近十多年来，随着国内经济的快速发展，我国桥梁建设也进入了最辉煌的发
展时期，截至目前，我国大陆已建成千米以上大跨度桥梁已经有数十座之多。值
得注意的是，美国、欧洲以及日本等的大跨度桥梁较多采用沉箱基础，而我国绝
大多数采用钻孔灌注桩群桩基础，其中在深水场地下又多为高桩承台结构形式，
形成了我国大跨度桥梁基础类型独特而鲜明的特点，如表 1.1 所示[1-3]，这充分显
示出钢护筒混凝土灌注桩在国内大跨度桥梁基础建设中应用的广泛性。
表1.1 国内外典型大跨度桥梁基础
桥梁名称
国别
主跨
基础类型描述
苏通长江大桥
中国
1088m
南北塔均为高桩承台，桩径2.8/2.5m 变截面
昂船洲大桥
香港
1018m
低桩承台基础，桩径2.8m
Rion-Antirion Bridge
希腊
3×560m
减隔震基础
鄂东长江大桥
中国
926m
南塔低桩承台，桩径2.5m；北塔高桩承台，桩径2.8/2.5m 变截
面
Normandy Bridge
法国
856m
低桩承台，桩径2.1m
荆岳长江大桥
中国
816m
南塔低桩承台，桩径2.2m；北塔高桩承台，桩径3.0m
东海大桥（颗珠山）
中国
420m
南北塔均为高桩承台，桩径2.5m
杭州湾大桥（北航道）
中国
448m
南北塔均为高桩承台，桩径3/2.5m 变截面
Akashi Kaikyo Bridge
日本
1991m
沉箱基础
西堠门大桥
中国
1650m
低桩承台，桩径2.8m
Great belt Bridge
丹麦
1624m
沉箱基础
润扬长江大桥
中国
1490m
南塔低桩承台，桩径2.8m；北塔高桩承台，桩径2.8m
南京长江四桥
中国
1560m
南北塔为高桩承台，南塔桩径3.2/2.8m 变截面，北塔桩径2.8m
Tataro Bridge
日本
890m
沉箱基础
江阴长江大桥
中国
1385m
感潮河段，低桩基础，桩径3m
青马大桥
香港
1377m
沉箱基础
Gold Gate Bridge
美国
1280.2m
沉箱基础
响礁门大桥
中国
951m
高桩承台，桩径2.5m
Verrazano Bridge
美国
1298.5
沉箱基础
Humber Bridge
英国
1410m
北塔为混凝土阀式基础，南塔为沉箱基础
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作者：侯斌
分类：高等教育资料
价格：15积分
属性：75 页
大小：3.61MB
格式：PDF
时间：2025-01-09
