Vibration model of pile foundation considering nonlinearity of soil

考虑土体非线性的桩基振动模型

• 批准号: 07650662
• 负责人: KUSAKABE Kaoru
• 金额: $ 1.34万
• 依托单位: Kobe University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07650662/
• 关键词: Pile foundation; Pile-structure system; Under ground structure; Nonlinearity of soil; Nonlinear response; Hyogoken Nanbu Earthquake; Analisis model; Thin layred element method; 抗基礎; 抗基礎-構造物連成系; 地震応答解析; 土の非線形性; 非線形応答; 複素剛性; 起振機試験

The purpose of this research is to present the evaluation method of complex stiffness and input motion as dynamic properties of pile foundation considering the non-linearlity with respect to rigidity and damping of soil and to present the vibration model of pile foundation applicable to earthquake resistant design. Results obtained in this term are summarized as follows.1. Concerning the nonlinear response analysis of ground, effective stress analysis is adopted. The characteristics of response of filled ground under drastic earthquake such as Hyogoken Nanbu Earthquake are pointed out as follows ; Distribution of the horizontal acceleration reduces towards ground surface, the depth where the maximum curvature response occurs corresponds to the depth where the bending fracture of pile happens and more accurate hysteresis loop of ground can be obtained when the cyclic mobility is considered.2. Earthquake response of buildings with pile foundation is analyzed by thin layred element method. The followings are grasped by this analysis. i.e.the more the rigidity of the soil reduces, the more the input horizontal acceleration is reduced and the isolation effect of ground is develops. Through various investigations, this method using the thin layred element method and considering the soil nonlinearity by equivalent linealization procedure is found to be useful for the non linear earthquake response analysis of pile foundation.3. For the response analysis of building with basements, it is replaced by cylindrical tube and the ground beneath it is assumed as a soil column. This method uses the thin layred element method and takes equivalent rigidity and damping corresponding to the soil non-linearity. From the comparative study of observed results of earthquake and analytical results, this analysis method is justified to be useful for earthquake response analysis of building with basements.

本研究的目的是考虑土的刚度和阻尼的非线性，提出以复刚度和输入运动作为桩基动力特性的评价方法，并提出适用于抗震设计的桩基振动模型。本项研究的主要成果如下：1.对于地基的非线性反应分析，采用有效应力分析。指出了在兵越南部地震等强烈地震作用下填充地基的响应特征：水平加速度分布向地表逐渐减小，最大曲率响应发生的深度与桩弯曲断裂发生的深度相对应，考虑循环活动度时可以获得更准确的地基滞回线。2.用薄层单元法分析了桩基结构的地震反应。通过这一分析，我们掌握了以下几点。即土体刚度降低越多，输入水平加速度降低越多，地基的隔震效果越好。通过大量的研究表明，采用薄层单元法并通过等效线性化处理来考虑土体非线性的方法，对于桩基的非线性地震反应分析是有效的.对于带地下室的建筑物的反应分析，将地下室用圆柱筒代替，地下室下的地基假定为土柱。该方法采用薄层单元法，并根据土体的非线性，取等效刚度和阻尼。通过与实测结果的对比分析，表明该分析方法对带地下室结构的地震反应分析是有效的。

项目成果

岡野創、日下部馨、上島照幸: "媒介変数1次近似法による不確定な線形地盤の地震応答量の評価" 日本建築学会構造系論文報告集. Vol.490. 129-138 (1996)

Hajime Okano、Kaoru Kusakabe、Teruyuki Ueshima：“使用一阶参数近似法评估不确定线性地面的地震响应”日本建筑研究所结构科学论文报告卷 490. 129-138 (1996)

Kaoru KUSAKABE et al: "Response of a 25 story SRC residential building during the Hyogo-Ken Nanbu Earthquake" 11ht World Conference of Earthquake Engrg.(1996)

Kaoru KUSAKABE 等人：“兵库县南部地震期间 25 层 SRC 住宅楼的响应”第 11 届世界地震工程大会（1996 年）

福住忠裕、日下部馨、弥勒良晴: "埋立人工島における抗-上部構造物系の地震応答性状" 日本建築学会近畿支部研究報告集(構造系). Vol.37. 69-72 (1997)

福住忠宏、日下部熏、弥勒良春：“填海人工岛抗震系统的地震反应特性”日本建筑学会近畿分会研究报告（结构）37. 69-72（1997）。

日下部馨、福住忠裕、本多永平: "埋立人工島における杭の地震応答性状" 日本建築学会近畿支部研究報告集(構造系). Vol.37. 77-80 (1996)

Kaoru Kusakabe、Tadahiro Fukuzumi、Eihei Honda：“填海人工岛上桩的地震反应特性”日本建筑学会近畿分会研究报告（结构）37. 77-80（1996）。

日下部馨、福住忠裕、木場将雄: "兵庫県南部地震による埋立人工島地盤の応答解析" 日本建築学会近畿支部研究報告集(構造系). Vol.37. 73-74 (1996)

Kaoru Kusakabe、Tadahiro Fukuzumi、Masao Kiba：“兵库县南部地震引起的填海人工岛地面的响应分析”日本建筑学会近畿分会研究报告（结构）第 37 卷 73-74（1996 年）。