桥梁温度跨度对纵连底座板受力及配筋的影响

考虑轨道与桥梁相互作用特点,建立桥上CRTSⅡ型板式无砟轨道空间力学模型,分析桥梁温度跨度对纵连底座板制动力和伸缩力的影响,根据不同桥梁温度跨度下的纵向力,按极限状态法对纵连底座板进行配筋设计。结果表明:当桥梁温度跨度小于482 m时,纵连底座板最大制动力随着温度跨度增加迅速增大,温度跨度超过482 m后纵连底座板的最大制动力趋于稳定;纵连底座板最大伸缩力随着桥梁温度跨度线性增大;纵连底座板配筋率增幅小于桥梁温度跨度的增幅。

Influence of Bridge Temperature Span on Stress State and on Reinforcing Bars of Longitudinally-continuous Base Layer

In view of the characteristics of the interaction between track and bridge,a spatial mechanical model of CRTS-Ⅱ slab ballastless track on a bridge was established. And then for the longitudinallycontinuous base layer( LCBL),the influences of the bridge temperature span on the braking force and on the expansion / contraction force were analyzed. Furthermore,based on different longitudinal forces corresponding to different bridge temperature spans,the reinforcing bars of the LCBL were calculated and designed by the limit state design method. The results show that the maximal braking force of the LCBL increases rapidly with the increasing of the bridge temperature span when the bridge temperature span is less than 482 meters,but tending towards stability when the bridge temperature span is greater than 482 meters. Moreover,the maximal expansion / contraction force of the LCBL increases linearly with the increasing of the bridge temperature span. In addition,the increasing range of reinforcement ratio of the LCBL is smaller than that of the bridge temperature span.