中、美规范中受压构件的正截面承载力计算

对中国《混凝土结构设计规范》（GB 50010—2002）和美国ACI 318M—05规范中钢筋混凝土受压构件的最小和最大配筋率、正截面轴心受压、偏心受压承载力及其配箍构造的规定进行了对比分析。结果表明：对于轴心受压构件,美国规范中受压承载力的折减系数小于中国规范;随着受力状态由大偏心受压向小偏心受压过渡,美国规范抗力折减系数的变化与构件的受力破坏特征有关,而中国规范的抗力折减系数基本不体现大、小偏心受压构件受力破坏特征的影响;对于高强混凝土,中国规范在确定混凝土材料强度标准值时引入了脆性系数,而美国规范通过较高的配箍率规定来保证高强混凝土构件的受力破坏特征与普通混凝土一致。

Calculation of Design Methods for Flexure and Axial Strength of RC Columns in Chinese and American Codes

A calculation and comparison of maximum and minimum reinforcement ratio, axial compression of normal cross section, eccentric compression capacity as well as transversal reinforcement configuration strength under combined flexure and axial forces, details of ties for RC columns were presented between Chinese Code for Design of Concrete Structures （GB 50010--2002） and American Code ACI 318M 05. Results show that firstly, for axial compression members, the strength reduction factor of American Code is smaller than that of Chinese Code; secondly, from the eccentric loaded column with tension failure to that with compression failure, the structural strength reduction factor of American Code changes with the failure mode, while that of Chinese Code does not; thirdly, for high-strength concrete, the brittleness factor is introduced to determine the nominal concrete material strength in Chinese Code, while a relatively larger stirrup reinforcement ratio is used in American Code to ensure that the failure mode of high-strength concrete is same to that of common concrete.