等效梁柱法计算钢筋混凝土拱承载力

为计算钢筋混凝土拱的承载力,通过将钢筋混凝土拱等效成相应长度的偏压柱,然后按偏压柱的公式进行承载力计算.对中国规范、美国规范、日本规范中拱圈计算长度取值方法进行比较,结合所收集的55座钢筋混凝土拱桥资料,发现在常用的矢跨比范围内,三个规范的拱圈计算长度取值基本一致.为验证拱圈计算长度取值的合理性,分别采用经过试验验证的有限元法和等效梁柱法,对一座钢筋混凝土拱桥主拱的承载力进行计算,并进行参数分析,发现等效梁柱法的计算结果均低于有限元法的计算结果,偏于安全.

Calculation of load-carrying capacity of reinforced concrete arch basing on equivalent beam-column method

It is pointed out that the equivalent beam-column method which is used in the calculation of load-carrying capacity of reinforced concrete arch bridge in our country is unreasonable. The theory basis of the equivalent beam-column method is analyzed, and the accuracy of this calculation method which depends on the rationality of load-carrying capacity calculation methods of eccentrically-loaded reinforced concrete column and the taking-value method of calculation length of arch ring is pointed out also; the existing problems on the calculation of load-carrying capacity of eccentrically-loaded reinforced concrete columns are analyzed, and the relative studies conducted and research results are introduced also; the taking-value methods of the calculation length of arch ring in Chinese codes, the United States codes and Japanese codes are compared, and the data of 55 reinforced concrete arch bridges are collected, it is found that the calculation length of arch ring in three codes are almost the same within the scope of the commonly used rise-span ratio ; in order to test and verify the applicability of the equivalent beam-column method, the load-carrying capacities of the main arch of one reinforced concrete arch bridge are calculated by finite element method verified by test and equivalent beam-column method respectively, and the parameter analysis method is used also, it is found that the calculation results by the former method are greater than the results by the latter method, which illustrates that the calculation results by the equivalent beam-column method are conservative.