Fundamental Research on High Seismic Performance RC Piers with Unbonded Bars

高抗震无粘结钢筋混凝土墩基础研究

• 批准号: 13450180
• 负责人: IEMURA Hirokazu
• 金额: $ 9.54万
• 依托单位: Kyoto University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2003
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13450180/
• 关键词: unbonded bars; RC structure; cyclic loading tests; pseudodynamic tests; single column pier; rigid frame pier; post-yield stiffness; seismic design method; 鋼より線; 付着剥離制御; 二段階耐震設計法; 合理的設計

In this study, the UBRC structure was proposed as the high seismic performance structure in the next generation. And, the cyclic loading tests and the pseudodynamic tests were carried out in order to obtain the fundamental performance. Furthermore the analytical method for the UBRC structure was developed, and we carried out the parametric studies. From this study, the following results are obtained:(1) By installing unbonded bars, it is possible to easily realize the RC structure with the stable post-yield stiffness. And the UBRC structure has small residual displacement in comparison with the conventional RC structure by the bar effect.(2) The capacity of the energy dissipation is only depend on the amount of longitudinal reinforcement, and never change due to the installation of bars. That is to say, the optimal amount of longitudinal reinforcement for the UBRC structure is the equivalent to that of RC structure in order to expect the energy dissipation.(3) From the results of the cyclic loading tests, it can be obtained the equivalent results to the principle got by installing the elastic member into RC structures. This structure can be realized only by installing unbonded bars into RC structure. Therefore this structure can be constructed with simple and easy construction works and low cost.(4) In order to increase the post-yield stiffness, we have three method; Increase the bar ratio, Place bars outside and Shorten the bar length. By installing the gap at the anchor, the post-yield stiffness doesn't change. Changing these parameters, the various kind of the load -displacement hysteresis can be realized.(5) In the pseudo dynamic tests it is also recognized the bars' effect (stable post-yield stiffness and the small residual deformation). Considering with the easy construction and the low construction cost, the UBRC structure has the high seismic performance.

在本研究中，UBRC结构被提出为下一代高抗震性能结构。并进行了循环加载试验和拟动力试验，以获得其基本性能。在此基础上，提出了UBRC结构的分析方法，并进行了参数研究。研究结果表明：(1)通过设置无粘结钢筋，可以方便地实现具有稳定屈服后刚度的钢筋混凝土结构。与传统钢筋混凝土结构相比，由于杆件效应，UBRC结构的残余位移较小。(2)耗能能力仅取决于纵向配筋量，不会因配筋的设置而改变。也就是说，UBRC结构的最优纵向配筋量与RC结构的纵向配筋量相当，才能达到预期的耗能效果。(3)从循环加载试验的结果来看，可以得到与在RC结构中安装弹性构件的原理相同的结果。这种结构只有在钢筋混凝土结构中安装无粘结钢筋才能实现。为了提高屈服后的刚度，我们采用了三种方法：增加配筋率、在外侧放置配筋和缩短配筋长度。通过在锚杆上安装间隙，屈服后的刚度不会改变。通过改变这些参数，可以实现各种形式的荷载-位移滞回效应。(5)在拟动力试验中，也认识到了杆件的影响(稳定的屈服后刚度和较小的残余变形)。考虑到UBRC结构施工简单、造价低，具有较高的抗震性能。

项目成果

高橋良和, 家村浩和: "アンボンド芯材入りRC構造の解析モデルと芯材パラメータの影響"構造工学論文集. Vol.49A. 995-954 (2003)

Yoshikazu Takahashi、Hirokazu Iemura：“无粘结芯材的 RC 结构分析模型及芯材参数的影响”《结构工程杂志》第 49A 卷（2003 年）。

家村浩和, 高橋良和: "小規模断面を有するUBRC橋脚の二段階耐震性能評価"土木学会第58回年次学術講演会講演概要集. Vol.V. V-352 (2003)

Hirokazu Iemura、Yoshikazu Takahashi：“小截面 UBRC 桥墩的两阶段抗震性能评估”日本土木工程师学会第 58 届学术年会摘要 V-352（2003）。

家村浩和: "高耐震化芯材の定着条件がRC橋脚の弾塑性挙動に及ぼす影響"平成13年度土木学会関西支部年次学術講演概要. V-27 (2001)

Hirokazu Iemura：“高抗震核心材料锚固条件对 RC 桥墩弹塑性行为的影响”2001 年日本土木工程师学会关西分会年度学术讲座摘要 V-27 (2001)。

Iemura, H., Takahashi, Y.: "Rational Seismic Design for Railway Elevated Bridges using UBRC Members (in Japanese)"Proceedings of 26th JSCE Earthquake Engineering Symposium. Vol.2. 921-924 (2001)

Iemura, H.，Takahashi, Y.：“使用 UBRC 构件的铁路高架桥的合理抗震设计（日语）”第 26 届 JSCE 地震工程研讨会论文集。

家村浩和: "ハイブリッド地震応答実験による高耐震化芯材を用いたRC橋脚の性能評価"第26回地震工学研究発表会講演論文集. Vol.2. 929-932 (2001)

Hirokazu Iemura：“通过混合地震响应实验对使用高抗震核心材料的 RC 桥墩进行性能评估”，第 26 届地震工程研究会议论文集，第 2 卷，929-932（2001 年）。