高墩小半径曲线梁桥支点预偏心时力学性能分析

Mechanical Characteristics Analysis of Small Radius Curve Beam Bridge with Pivots Pre-eccentricity with High Piers

高墩小半径曲线梁桥是具有复杂力学性能的空间结构体系。为探寻高墩小半径曲线梁桥的合理支承形式,以此来保证高墩小半径曲线梁桥的安全,需要确保采用合理的支点预偏心。本文采用有限元方法分析了曲线梁桥主要力学性能随支点预偏心的变化规律,研究了曲率半径及墩高对曲线梁桥支点预偏心前后力学性能的影响,探讨了高墩和小半径皆为曲线梁桥受力不利因素的原因。研究了支点预偏心方法减小高墩小半径曲线梁桥主梁的扭矩、扭转变形、墩顶弯矩、水平位移以及两端双支座竖向反力差的性能。研究结果表明:合理的支点预偏心方法可以减小曲线梁桥结构的内力、变形以及支座反力。高墩和小半径皆为曲线梁桥的不利因素,对高墩小半径曲线梁桥设置支点预偏心至关重要。

Small radius curve beam bridge with high piers is a spatial structure system with complex mechanical performance. In order to research the reasonable form of bearing for the safety of the congener bridge, the reasonable pre-eccentrieity of pivots would be adopted. In this paper, the rules of the mechanical characteristics of curve beam bridge with pre-eccentricity of pivots are studied with finite element method, the effect of the radius and that of the height of piers on the mechanical characteristics of curve beam bridge with pivots pre-eccentricity are studied in this paper as well. The reasons for Small radius and high piers are beth disadvantages for mechanical characteristics of curve beam bridge are discussed in details. Moreover, the properties of the method of pivots pre-eccentricity to reduce the torsion and torsion deformation of the beam, the moment and horizontal displacement of the piers at the top and the difference of vertical reaction force of the two bearings at the two ends are studied. The result of research shows： the reasonable pre-eccentricity of pivots can reduce the internal force and deformation and reaction force of the curve beam bridge structure. Small radius and high piers are beth disadvantages for mechanical characteristics, it is so important to set pre-eccentricity of pivots for small radius curved beam bridge with high piers.