AN INVESTIGATION ON THE DYNAMIC BEHAVIOR OF SUBMERGED FLOATING TUNNELS

水下浮动隧道动力行为研究

基本信息

批准号：
09555140
负责人：
MIKAMI Takashi
金额：
$ 2.62万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09555140/
关键词：
Submerged floating tunnel Wave Earthquake Dynamic problem Snap and slack Tension leg Beam on elastic foundation Beam on elastic supports 波浪応答簡易解析モデル規則波波浪動機地震時動機

项目摘要

The purpose of this study is to investigate the characteristics of the dynamic behavior of submerged floating tunnels under wave and seismic action, which are critical forces in design. Moreover, effective beam model for discussion on the design of structure is also presented.The most important findings under wave force are summarized as follows;For leg arrangement Type-A :1. Although lateral displacement is great, slack is least likely to occur with this arrangement.2. The rigidity of the joints between tunnel elements has a major effect on the lateral displacement of the tunnel as a whole. The ideal type of joint for Type-A would be a pin joint. Lateral displacement and the maximum bending moment in rigid joints increases with the angle of wave incidence.For leg arrangement Type-C :1. Lateral displacement is much less than in type A, but slack is more likely to occur.2. No significant variations in lateral displacement are found with different joint rigidities.The results of analysis under seismic wave can be summarized as follows:1. If the natural period of the structures is long enough comparing to the predominant period of seismic wave, maximum response of displacement or bending moment for design are approximately predictable by an analysis with simultaneous excitation. When the natural period of the structure is close to the predominant period of seismic wave, propagation velocity plays an important role for dynamic response and it should be taken into account.2. For prediction of sectional force like the bending moment at the joints, propagation velocity should be carefully decided.In order to discuss the global behavior of the structure, a beam model on elastic foundation is developed for submerged floating tunnel with tension legs spaced at equal interval. It Is shown that the approximation of a uniform continuous elastic foundation is reasonable whenever kィイD2vィエD2hィイD13ィエD1/(6EI)≦0.2.

这项研究的目的是研究在波浪和地震作用下淹没浮动隧道动态行为的特征，这是设计中的关键力。此外，还提出了用于讨论结构设计的有效梁模型。波力下最重要的发现如下所示；对于腿部排列，A型A：1：1。尽管横向位移很大，但这种布置中最不可能发生松弛。2。隧道元素之间关节的刚度对整个隧道的横向位移有重大影响。 A型A关节的理想类型是销接头。刚性接头中的横向位移和最大弯矩随着波动的角度而增加。对于腿部排列类型-C：1。横向位移远低于A型，但松弛更可能发生2。没有发现不同关节刚度的横向位移的显着变化。地震波下的分析结果可以总结如下：1。如果结构的自然周期与地震波的主要时期相比足够长，则通过简单兴奋的分析，可以预测的位移或弯曲力矩的最大响应是可以预测的。当结构的自然时期接近地震波的主要时期时，传播速度对于动态反应起着重要作用，应考虑到2。为了预测截面力，例如关节处的弯矩，应仔细确定传播速度。在讨论结构的全球行为中，弹性基础上的梁模型是为浸入式浮动隧道开发的，其张力腿在相等的间隔内间隔间距。结果表明，每当K-D2VIE D2H-D13-D1/（6EI）≦0.2时，均匀连续弹性基础的近似是合理的。