漸進式崩塌中之動力放大因子試驗與分析

An Experimental Study of the Dynamic Amplification in Progressive Collapse Analysis

游智國(Chih-Kuo Yu)

指導教授 ： 蔡孟豪

國立屏東科技大學/工學院/土木工程系所/碩士(2011年)

https://doi.org/10.6346/NPUST.2011.00233

摘要

本研究規劃一小型試驗裝置，量取一單跨細長懸臂鋼構梁於喪失支撐後的瞬間動態反應，藉以探討動力放大因子於彈塑性行為下之變化。試驗主要分為靜力試驗與動力試驗，試驗採用鉛塊或質量塊作為外加載重，模擬不同載重之變化情形。試驗將掛勾勾上視為基準線，以模擬懸臂鋼構梁試體的支撐，以鐵鎚瞬間敲除掛勾的方式模擬瞬間喪失支撐的動態行為，將此視為動力試驗，而靜力試驗是將掛勾敲除後讓試體緩慢的下降。由靜力試驗得到的載重-位移曲線關係，推得出一容量曲線，用以評估動力試驗所需的載重大小。由鋼構梁自由端位移與鋼構梁固定端的應變反應，比較不同動力放大因子的差異。試驗結果顯示，動力放大因子於彈性範圍，其值皆趨近於2.0，當動力放大因子於塑性範圍，採用相同載重下動力最大位移與靜力位移得到的「位移比」動力放大因子會大於2.0；而以相同位移需求下，靜力載重與動力載重得到的「載重比」動力放大因子會小於2.0。以動力最大反應與動力平衡反應比值估計的方式，並無法正確的呈現材料塑性行為對動力放大因子之影響。

關鍵字

動力放大因子 ； 漸進式崩塌 ； 靜力試驗 ； 動力試驗 ； 容量曲線

並列摘要

In this study, a small-scale test setup has been designed for simulating the sudden support-loss behavior of a supported clamped beam. The aim of this experimental study is to investigate the effect of material nonlinearity on the dynamic amplification factor (DAF) under sudden suppot loss. Experimental include static test and dynamic test. A capacity curve, which is constructed from the nonlinear static load-displacement response, may be applied to approximate prediction of the collapse resistance and the DAF for a column-removed building. Experiment was measured the steel beam displacement of free end and the fixed end of the strain response, compare to the differences in dynamic amplification factor. The displacement-based DAF is defined as the ratio of the dynamic displacement response to its static displacement response under equal applied loading. On the other hand, the force-based DAF is defined as the ratio of the static forec to the dynamic force under equal displacement demand. The test results show that dynamic amplification factor in the elastic range, its value are approximate to 2.0. Then the dynamic amplification factor in the plastic range, the displacement-based DAF is greater than 2.0, and the force-based DAF is less than 2.0.

並列關鍵字

dynamic amplification factor ； progressive collapse ； static test ； dynamc test ； capacity curve

參考文獻

9. 黃翠薔，「含牆RC構架喪失底層柱之彈塑性反應行為研究」，國立屏東科技大學研究所碩士論文，屏東，2010。

20. 呂偉正，「鋼筋混凝土建築物之漸進式倒塌分析之方法探討」，中原大學研究所碩士論文，桃園，2009。

24. 蔡孟豪、林秉輝，「RC建築物之漸進式崩塌強度與動力放大因子分析」，中國土木水利工程學刊，第二十一卷，第一期，461-471頁，2009。

1. Pearson, C., and Delatte, N., “Ronan Point Apartment Tower Collapse and its Effect on Building Codes,” Journal of Performance of Constructed Facilities, ASCE, Vol.19, No. 2, pp. 172-177, 2005.

3. Mohamed, O.A., “Progressive Collapse of Structures: Annotated Bibliography and Comparison of Codes and Standards,” Journal of Performance of Constructed Facilities, ASCE, Vol. 20, No. 4, pp. 418-425, 2006.