钢筋混凝土拱桥极限承载力的参数研究

采用压溃理论和三维仿真模型，分析了钢筋混凝土拱肋在几何非线性、材料非线性、几何缺陷以及混凝土压碎、开裂、骨料嵌锁等因素耦合作用下的极限承载力，以使它的确定更符合实际．重点研究了初始几何缺陷、截面形式、荷载形式和矢跨比等对钢筋混凝土拱肋极限承载力的影响．研究结果表明：混凝土材料的力学特性对大跨径钢筋混凝土拱桥的极限承载力有明显影响；大跨径钢筋混凝土拱肋的极限承载力随初始几何缺陷的增加按分段二次曲线规律减小，与拱肋长细比遵循三次曲线关系规律．

Parametric Investigation of Ultimate Bearing Capacity of Reinforced Concrete Arch Bridges

Based on the collapse theory and a 3D numerical simulation model, the ultimate bearing capacity of reinforced concrete arch ribs was calculated to accurately determine the ultimate bearing capacity of a long-span reinforced concrete arch bridge. In this research, the effects of geometric nonlinearity, material nonlinearity, geometric imperfection, concrete crush, concrete crack and aggregate interlocking were taken into account. The effects of geometric imperfection, cross-section type, load distribution form and raise-to-span ratio on the ultimate bearing capacity were mainly discussed. The results show that the mechanical characters of reinforced concrete have a great effect on the ultimate bearing capacity, the ultimate bearing capacity varies nonlinearly with the initial geometric imperfection, and the relationship between the ultimate bearing capacity and the length to radius ratio of arch rib is a cube curve.