Evaluation of Ultimete Limit State Strength of Steel Structures

钢结构极限状态强度评价

基本信息

批准号：
63460170
负责人：
TAKANASHI Koichi
金额：
$ 4.22万
依托单位：
Institute of Industrial Science, University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1989
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-63460170/
关键词：
failure mode external excitation inertial force static loading test dynamic loading test ultimate state aseismatic design 限界状態設計結局限界状態地震応答風応答オンライン応答実験

项目摘要

The purpose of this study is to find the failure mechanism of frame in ultimate state which dissipates a input energy to the frame by earthquake excitations or wind loading.There were three types of tests conducted static tests, earthquake response tests and dynamic response tests by wind loading.All these tests were conducted on 3-story frames and were controlled by the On-line test technique.The test results are summarized below:(1) The strength observed at the static tests is much higher than the strength which is calculated by a simple plastic analysis for perfectly elastoplastic materials. In order to evaluate correctly the strength of frame, it is very important to take into account the strain-hardening effect at the strength analysis of frame.(2) The trajectories of the inertial forces are crowed along the line representing the ratio between the inertial forces during the 1st mode vibration. It suggests the possibility of representing the dynamic load effects by an equivalent static load.It is possible to develop the simple ultimate state aseismatic design method characterized by equivalent static parameters, in the case of comparatively small effects of higher mode of vibration in frames.Considering the interactive effects between velosity of frame and wind verosity at the wall exposing to the wind, the dynamic loading distribution exerting at the each floor of frame is nearly equal to the static wind loading distribution. The 1st mode vibration in dynamic response, however, are dominant. Then, there are no interactive relation between the ratios of the work done by the static shear force at the each floor and by the dynamic loads.

本研究的目的是找出极限状态下框架的破坏机制，该机制通过地震激励或风荷载耗散框架的输入能量。试验分为静态试验、地震响应试验和风动力响应试验三种类型。所有这些试验均在三层框架上进行，并通过在线试验技术进行控制。试验结果总结如下：（1）静态试验中观察到的强度远高于由下式计算的强度：完美弹塑性的简单塑性分析材料。为了正确评价车架的强度，在车架强度分析中考虑应变硬化效应非常重要。(2)惯性力的轨迹沿着代表惯性力与惯性力之比的直线。第一模式振动期间的力。它提出了用等效静载荷来表示动载荷效应的可能性。在框架中较高振动模式的影响相对较小的情况下，可以开发以等效静参数为特征的简单极限状态抗震设计方法。考虑到由于框架速度与受风墙风速的相互作用，框架各层的动荷载分布与静风荷载分布基本相等。然而，动态响应中的第一模式振动占主导地位。那么，各层静剪力所做的功与动荷载所做的功之比之间不存在交互关系。