曲线连续梁桥支承布置形式对主梁结构扭矩的影响分析

曲线连续梁桥受力较为复杂,主梁的平面弯曲使得下部墩柱的受力支承点不在同一条直线上,从而产生较大的扭矩和扭转变形,构成了其独有的受力特点.如何控制主梁结构的扭矩,限制扭转变形对于桥梁结构安全至关重要.目前通常采用减小翼缘宽度和增大箱室,加大梁高和腹板厚度两项措施来改善主梁截面的抗扭性能.以工程实例为背景,通过改变曲线箱梁桥的支承布置,可以更加方便高效地改变主梁结构扭矩的分布,达到扭矩均衡的目的.

Analysis on Influence of Supporting Layout Form of Curved Continuous Beam Bridge on Structural Torque of Main Girder

The stress of curved continuous beam bridge is more complex. The plane bending of the main girder makes the stress supporting point of the lower pier not in a same straight line so as to cause larger torque and torsional deformation and to constitute its unique stress characteristics. How to control the torque of the main girder structure and restrict the torsional deformation are of great importance for the safety of bridge structure. At the present, the flange width is decreased and the box chamber is increased normally. Two measures of increasing the beam height and the web thickness are taken to improve the torsional properties of the main girder section. Taking an engineering case as the background, through changing the supporting layout of curved box beam bridge, the distribution of the structural torque of the main girder can be more conveniently and effectively changed to reach the purpose of torque balance.