Reliability-based studies of minimum and maximun flexural reinforcement in reinforced concrete beams

• Main Authors: Kaung-Chaung Cheng, 鄭光壯
• Other Authors: Shyh-Jiann Hwang
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/97665401554831991760

碩士 === 國立臺灣科技大學 === 營建工程技術學系 === 84 === To assessing the structural safety, the code provisions should be formulated by the reliability theory with the concern of the uncertainties in materials and loads. Although the load and resistance factors in current codes have been carefully treated through the reliability calculations, most of the detailing provisions are highly empirical and deterministic in form. Therefore, further probabilistic evaluations are needed for thoes detailing rules. This study examines the reliability of the minimum (.blksq.) and maximum (.blksq.) steel content requirements for reinforced concrete beams. Taking the reliability index .beta.=3.0 as a qualified value, it is then observed that the .blksq. in ACI 318-95 Code for the normal strength concrete beams are reliable, but unreliable for the high strength concrete beams. For the .blksq. of the statically indeterminate T-section with flange in tension must be increased about 60% to reach the amount of .blksq.=.blksq. for just being qualified. Forthermore, the maximum steel content requirement .blksq. .ltoreq. 0.75 .blksq. in ACI 318-95 Code is also examined based on the Monte Carlo simulation. The .blksq. .gtoreq. 0.6 .blksq. is suggested in this study to satisfy the requirement of reliability index .beta. .gtoreq. 3.0.