大节段装配式波形钢腹板组合T梁横向分布系数研究

Research of the Lateral Distribution Factors of Large-segment Prefabricated T-girder with Corrugated Steel Webs

为探索新型结构波形钢腹板组合T梁桥的荷载横向分布情况,针对跨径为60 m的大节段装配式波形钢腹板组合T梁桥进行工程设计。基于ANSYS建立有限元模型,研究不同横隔板构造形式及间隔变化对荷载横向分布系数的影响,确定横隔板最优布置方式,并将有限元法与传统的荷载横向分布计算方法进行对比。结果表明:3种构造形式的横隔板均能在一定程度上降低荷载横向分布影响线竖标值的峰值,使荷载横向分布影响线更加平缓。X型钢桁架横隔板与V型钢桁架横隔板刚度相差很小,且前者略高于后者,钢板式横隔板改善荷载横向分布最明显。对于边梁,3种构造形式下荷载横向分布系数相比无横隔板时下降均不足1%,中梁的荷载横向分布系数相比无横隔板时最大降低了3.2%。X型钢桁架作用下的边梁荷载横向分布系数略优于V型钢桁架作用下的荷载横向分布系数,而中梁与之相反。相同构造形式下横隔板的间隔变化对荷载横向分布影响线的影响很小,建议选择10 m间隔V型钢桁架作为横隔板。采用刚接梁法计算波形钢腹板组合T梁是较为合适的方法,计算所得边梁横向分布系数比有限元法高6.92%,中梁横向分布系数比有限元法高1.22%。

In order to explore the load lateral distribution of the new structure composite T-girder bridge with corrugated steel web,a 60-meter-span large-segment prefabricated composite T-girder bridge with corrugated steel web was used for engineering design.A finite element model was established based on ANSYS to study the influence of the structural form and spacing of the diaphragm on the lateral load distribution,and to determine the most optimal layout,the finite element method was compared with the traditional lateral distribution calculation methods.The results showed that the transverse diaphragms of the three structural forms could reduce the peak value of the vertical mark value of the influence line of the load lateral distribution to a certain extent,and make the influence line of the load lateral distribution more smooth.The stiffness difference between the X-shaped steel truss diaphragm and the V-shaped steel truss diaphragm was very small,and the former was slightly higher than the latter.The steel plate type diaphragm improved the lateral load distribution most obviously.For the side beam,the load lateral distribution factors under the three structural forms were all less than 1%lower than that without the diaphragm,and the load lateral distribution factors of the center beam was reduced by 3.2%at the maximum compared with the case without the diaphragm.The lateral load distribution factor of the side beam under the action of the X-shaped steel truss was slightly better than the lateral load distribution factor under the action of the V-shaped steel truss,while the center beam was the opposite.The change of the interval of the diaphragm under the same structure had little effect on the influence line of the load lateral distribution.It was recommended to choose V-shaped steel trusses with an interval of 10 meters as the diaphragm.The rigid connected beam method was suitable to calculate the composite T-beam with corrugated steel webs.The difference between the lateral distribution factor of the side girder and the finite element method was about 6.92%,and the difference between the middle girder and the finite element method was about 1.22%.