异形变截面多室曲线箱梁桥的试验研究及三维有限元分析

Three-dimensional FE Analysis and Experimental Study of Irregular Polythalamous Curved Box Girder Bridge with Variable Cross-section

在对某异形变截面多室曲线箱梁桥试验研究的基础上,构造可以综合考虑拉压、弯扭、畸变、剪力滞及其耦合作用的三维虚拟层合单元法,并对该异形桥梁进行空间有限元分析。理论分析和试验研究表明,利用此法对这种复杂的异形桥梁结构进行空间分析,具有模型单元少、计算效率和精度高的特点,完全可以满足实际工程的需要,是一种简单方便的实用计算方法。最后,综合考虑在一期恒载和纵向预应力筋作用下其应力的空间分布情况。研究成果可供工程设计和施工参考。

Based on the experimental study of an irregular polythalamous curved box girder bridge with variable cross-section, this paper proposes the method of three-dimensional virtual laminated element,which can take into account of tensile compression effect, blank tear effect, distortion effect, shear log effect and their coupling effects. The comparison between experimental and analytical results shows that the spatial analysis of the irregular complicated bridge structures has many merits such as the fewer elements, the higher computational efficiency and the higher computational precision, etc. The proposed method is convenient and practical,in which the required precision for engineering practice can be easily achieved. In the end, the distributed regularities of spatial stresses of the irregular bridges under the permanent load and longitudinal prestressing force are analyzed in this paper. The research results can be useful in the engineering practice and design.