Study on Pile Head Joint by Energy Absorbing Method

吸能法桩头接头研究

• 批准号: 14550556
• 负责人: MITSUJI Kazuya
• 金额: $ 2.62万
• 依托单位: Tohoku 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 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14550556/
• 关键词: PHC pile; pile head joint; stub bar; lead damper; cyclic horizontal load test; rocking; shaking table test; 模型振動台実験; 固定接合; ダンパー; 模型地盤; 固有振動数; 鉛

A cyclic horizontal load test was performed on a real size test specimen of pile head joint. A PHC pile with 50cm in diameter, welded 8 stud bars to end face and burned 5 cm into foundation slab, was used as test specimen. Stud bars are bound up by lead. The foundation slab is fixed to the floor, and cyclic horizontal load is applied to pile, under the axial load of 98OkN, at 1.75m up from the surface of foundation slab. The reason why the stud bars are bound up by lead is to expect damper effect of lead that the stud bars are moving in lead under the rocking motion of pile head by cyclic horizontal load.As a test result, the following is obtained. Load-displacement relation keeps linear state up to the load level corresponding to the short-term allowable bending moment of pile, but exceeding that level, changes to S-shaped wide hysteresis roop until the ultimate state, i.e., damper effect of lead is displayed clearly. Cracks are observed on the surface of foundation slab at the step of displacement of pile head 28mm. By progressing these cracks, producing other cracks and connecting mutually, the final state becomes the surface concrete surrounding the pile comes off totally.A shaking table test was also performed for 2 box-type superstructures supported by laminar piles in shearing soil-box, the first one of which is fixed condition at pile head joint and the second one is damper condition by using visco-elastic material. The main test results are as follows ; Natural frequency and response amplification are also lower in the case of damper model than the fixed model showing the damper effect clearly. The peak of sweep test appears also in the case of random wave input and earthquake input motion. As the revel of input motion is larger, effects of non-linearity of model ground appears still more.

对桩头接头的真实的尺寸试件进行了水平循环荷载试验。试件为直径50 cm的PHC桩，桩端焊8根短柱，桩底埋深5cm。螺栓杆用铅包着。基础底板固定在楼板上，桩体在距基础底板表面1.75m处施加循环水平荷载，轴向荷载为98 OkN。采用铅对桩柱进行绑扎的目的是为了使桩柱在水平循环荷载作用下桩头的摇摆运动中产生铅的阻尼作用。荷载-位移关系在达到桩的短期容许弯矩所对应的荷载水平之前保持线性状态，超过该水平后，变为S形宽滞回曲线，直至极限状态，即，铅的阻尼效应清晰地显示出来。在桩顶位移28 mm处，基础底板表面出现裂缝。通过这些裂缝的发展，产生其他裂缝，并相互连接，最终形成桩周表层混凝土的整体脱落。对2个剪切土箱中层状桩支承的箱型上部结构进行了振动台试验，第一种情况为桩头节点固定状态，第二种情况为粘弹性材料阻尼状态。试验结果表明：阻尼器模型的自振频率和响应放大率均比固定模型低，阻尼效果明显。在随机波输入和地震动输入情况下，扫频试验也出现峰值。随着输入运动的变化，模型地面非线性的影响更加明显。

项目成果

津田和義, 杉村義広, 大杉文哉, 中島隆裕, 椿原康則, 遠藤年誠: "エネルギー吸収を考慮した杭頭接合方法に関する実験研究(その9 ロッキングを利用した鉛ダンパーによる応答制御の解析モデル)"日本建築学会大会. B-1. 631-632 (2003)

Kazuyoshi Tsuda、Yoshihiro Sugimura、Fumiya Osugi、Takahiro Nakajima、Yasunori Tsubakihara、Toshimasa Endo：“考虑能量吸收的桩帽连接方法的实验研究（第 9 部分：使用摇摆的铅阻尼器的响应控制分析模型）” 日本建筑学院会议 B-1。631-632（2003）

TANAKA Go, SUGIMURA Yoshihiro, HIRADE Tsutomu, IKENAGA Masayoshi, MOCHIMARU Masami, MURAKAMI Masakatsu: "Experimental Study on Pile Head Joint for Energy Absorbing Method, Part 8 Development of Lead Damper for Pile Head Joint"Summaries of Technical Papers

TANAKA Go、SUGIMURA Yoshihiro、HIRADE Tsutomu、IKENAGA Masayoshi、MOCHIMARU Masami、MURAKAMI Masakatsu：《桩头接头能量吸收法的实验研究，第 8 部分桩头接头用铅阻尼器的开发》技术论文摘要

HIRADE Tsutomu, SUGIMURA Yoshihiro, MURAKAMI Masakatsu, ENDO Toshinari, TAKANO Kenji, KATSURAGI Masao: "Experimental Study on Pile Head Joint for Energy Absorbing Method, Part 13 Outline of Shaking Table Test of Structure Model Using Damper in Pile Head J

HIRADE Tsutomu、SUGIMURA Yoshihiro、MURAKAMI Masakatsu、ENDO Toshinari、TAKANO Kenji、KATSURAGI Masao：“桩头接头能量吸收方法的实验研究，第 13 部分使用桩头阻尼器的结构模型振动台试验概要 J

平出務, 杉村義広, 村上正勝, 遠藤年誠, 高野謙二, 桂木政雄: "エネルギー吸収を考慮した杭頭接合方法に関する実験研究(その13 杭頭にダンパー機能を有する建物模型の振動台実験結果概要)"日本建築学会大会. B-1(発表予定). (2004)

Tsutomu Hiraide、Yoshihiro Sugimura、Masakatsu Murakami、Toshimasa Endo、Kenji Takano、Masao Katsuragi：“考虑能量吸收的桩帽连接方法的实验研究（第 13 部分）在桩帽上具有阻尼功能的建筑模型的振动台实验结果概述）“日本建筑学会会议。B-1（演示时间表）。（2004 年）

TSUDA Kazuyoshi, SUGIMURA Yoshihiro, OHSUGI Fumiya, NAKAJIMA Takahiro, TSUBAKIHARA Yasunori, ENDO Toshinari: "Experimental Study on Pile Head Joint for Energy Absorbing Method, Part 9 Analysis Model of Response Control by Lead Damper using rocking Motion

TSUDA Kazuyoshi、SUGIMURA Yoshihiro、OHSUGI Fumiya、NAKAJIMA Takahiro、TSUBAKIHARA Yasunori、ENDO Toshinari：“能量吸收方法的桩头接头实验研究，第 9 部分使用摇摆运动的铅阻尼器响应控制分析模型