Development of Method for Estimating Lateral Resistance of Pile Groups in Liquefied Soil during an Earthquake

地震期间液化土中群桩侧向抗力估算方法的开发

• 批准号: 14550569
• 负责人: TOMINAGA Koji
• 金额: $ 2.56万
• 依托单位: HIROSHIMA UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14550569/
• 关键词: Effective stress in Soil; Lateral resistance of single pile; Lateral resistance of pile group; Space of piles; Number of piles; Coefficient of lateral soil reaction; Plastic lateral soil reaction; Liquefaction; 群杭の水平抵抗; 群杭水平抵抗; 初期水平抵抗剛性; 最大杭頭せん

The mechanism of the liquefaction in saturated sand and soil resistance during an earthquake has been gradually made clear since 1964 when the Niigata earthquake occurred. In recent years, however, the damages due to the liquefaction caused by the large earthquakes have been reported, for example the Hokkaido-nansei-oki earthquake in 1993, the Hyogoken-nambu earthquake in 1995, the Tottori-seibu earthquake in 2000, and so on. In the Hyogoken-nambu earthquake, the large-scale liquefaction occurred in the wide area from the former coastline to the reclaimed land, and the damages occurred in the pile foundation under buildings. The cause of damages of the pile foundations has investigated by some researchers. However, many uncertainties to establish the design method for laterally loaded piles supporting a building still remain, especially when considering effective stress reduction in soil around piles due to pore water pressure increasing during an earthquake. Therefore, we devised and … More made the appropriate test apparatus for decreasing effective stress in the test sand bed by using the seepage flow, and performed laterally loading tests in order to investigate the subgrade reaction acting on the model pile.The following points are found out from these studies :1.The lateral subgrade reaction on the pile at a given level is approximated by the hyperbola with respect to the lateral displacement of the pile. Then the initial modulus and the convergence of the hyperbola are related to the initial coefficient of the lateral subgrade reaction and the ultimate lateral subgrade reaction, respectively.2.Both of the initial coefficient of lateral subgrade reaction and the ultimate value increase linearly with depth (i.e. triangle distribution), and decrease linearly with decreasing the effective stress in the sand bed. From these results, we are able to present the new design method of pile foundations on the basis of the subgread reaction analysis which considers the reduction of effective stress in ground during an earthquake.3.Furthermore, the analysis for the pile group foundation based on the three dimensional theory, which considers an elasto-plastic continuum and the ultimate lateral resistance of the soil around the piles, is also proposed. Less

自1964年发生Niigata地震发生以来，在地震期间饱和砂和土壤耐药性中的液化机制逐渐明确。然而，近年来，据报道，由于大地震造成的液化造成的损害，例如1993年的北海道 - 北塞 - 北地震，1995年的风格汉布地震，2000年的Tottori-Seibu地震，等等。在风格的 - 南村地震中，大规模的液化发生在从以前的海岸线到回收土地的广阔地区，损失发生在建筑物下的桩基金会中。一些研究人员投资了桩基础的损失的原因。但是，许多不确定性建立用于支撑建筑物的横向钢琴的设计方法仍然存在，尤其是在考虑地震期间孔隙水压升高引起的钢琴周围土壤的有效压力减轻时。因此，我们设计并……更多地使适当的测试设备通过使用渗流流量来减轻测试砂床中的有效压力，并进行了横向加载测试，以调查作用于模型桩的亚级反应。从这些研究中发现以下几点。然后，双曲线的初始模量和收敛性分别与侧向亚级反应的初始核心和最终的横向子分级反应有关。从这些结果中，我们能够根据亚根反应分析呈现桩基础的新设计方法，该反应分析考虑了地震期间的有效压力的减少。3.Furthermore，基于三维理论的桩组基础的分析，基于三维理论，该理论考虑了弹性层状的连续性，该基础是弹性层状的连续性和最终对土壤的最终抵抗。较少的

项目成果

冨永晃司, 徐挺, 他3名: "有効応力制御地盤中群杭の水平抵抗実験(その2:実験結果の考察)"日本建築学会中国支部研究報告集. 第26巻. 207-210 (2003)

富永浩二、徐辉等3人：“有效应力控制地基中等群桩的水平阻力试验（第2部分：试验结果的讨论）”日本建筑学会中国分会研究报告26. 207-210（2003年） ) )

Fundamental Experiment on Lateral Subgread Reaction of Pile Group in Soil Controlled Effective Stress.

土体控制有效应力下群桩横向地基反应的基础试验。

• 发表时间: 2003
• 期刊: 38^<th> Japan National Conference on GE (CD)
• 作者: S.Nanba;K.Tominaga;T.Xu;others
• 通讯作者: others

有効応力制御地盤中群杭の水平抵抗実験

有效应力控制地基中群桩水平阻力试验

• 发表时间: 2003
• 期刊: 日本建築学会学術講演梗概集 構造系
• 作者: 山本典雅;徐挺;冨永晃司 他1名
• 通讯作者: 冨永晃司 他1名

冨永晃司, 徐挺, 他3名: "有効応力制御地盤中群杭の水平抵抗実験(その3:杭本数の影響)"日本建築学会中国支部研究報告集. 第27巻. 133-136 (2004)

富永浩二、徐辉等3人：“有效控制应力的地基中群桩的水平阻力试验（第3部分：桩数的影响）”日本建筑学会中国分会研究报告，第27卷，133- 136（2004））

Analytical Investigation of Horizontal Resistance of Pile Foundation in Controlled Effective Stress.

受控有效应力下桩基水平阻力的分析研究。

• 发表时间: 2002
• 期刊: 37^<th> Japan National Conference on GE (CD)
• 作者: H.Ariki;T.Xu;K.Tominaga;others
• 通讯作者: others