Effect of Simplified Pulse Shape on the Blast Response of a RC Column

• Main Authors: Cheng Long Chiang, 江承龍
• Other Authors: Meng-Hao Tsai
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/40686752591617361986

碩士 === 國立屏東科技大學 === 土木工程系所 === 97 === Linear time history analyses are conducted to investigate the blast response of a RC column. Exponential decay pulse and linear decay pulse are used to simulate the blast pressure wave. Three different approaches are used to obtain the simplified linear decay shapes for the exponential decay pulse. Elastic responses of the RC column subjected to those four different pulses with various positive phase durations and damping ratios are being compared. The simplified linear decay pulse with equal peak pressure and positive duration to that of the exponential decay pulse leads to fairly consistent response with that of the simplified linear decay pulse with equal impulse and peak pressure. Both simplified approach have approximated results to that of the exponential decay pulse as the wave parameter “b” is larger than 5. Response reduction caused by added damping deceases with positive duration. In addition, the results of nonlinear time history analyses show that due to the impulse effects of positive phase duration, the response increases as the pulse duration decrease. The linear and nonlinear analysis results indicate that all response spectra curves gradually become identical with time duration ratio Ts/Tn increase. Both simplified linear decay forms are conservative as compared to the exponential decay pulse in linear analysis, but may be slightly unconservative in nonlinear analysis.