UHPC 在槽形钢-混凝土组合梁的应用与分析

Application and Analysis of UHPC in Channel-section Steel-concrete Composite Beam

以某大跨连续钢-混凝土组合梁为工程背景,对钢-UHPC组合梁和钢-C50混凝土组合梁进行整体和局部对比分析。结果表明,整体计算中,钢-UHPC组合梁的刚度略小于钢-C50混凝土组合梁,基本组合下钢-UHPC组合梁中钢梁应力比钢-C50混凝土组合梁下降约27%。局部有限元分析中,频遇组合下钢-C50混凝土组合梁的桥面板已开裂;钢-UHPC组合梁桥面板的最大拉应力作用范围比钢-C50混凝土组合梁小,仅出现在纵肋下缘,且最大拉应力小于UHPC材料的开裂应力。钢-UHPC组合梁可大幅降低结构自重,进一步减小钢梁截面,有望解决大跨度连续组合梁中桥面板开裂问题。

Based on the background of a long-span continuous steel-concrete composite beam,the overall and local comparative analysis of steel-UHPC composite beam and steel-concrete C50 composite beam is carried out.The results show that the stiffness of the steel-UHPC composite beam is slightly smaller than that of the steel-concrete C50 composite beam in the overall calculation.The stress of the steel beam in steel-UHPC composite beam is about 27%lower than that of the steel-concrete C50 composite beam in fundamental combination.In the local finite element analysis,the bridge deck of steel-concrete C50 composite beam has cracked under frequent combination,the maximum tension stress of steel-UHPC composite beam bridge deck is less than that of steel-concrete C50 composite beam,which only appears at the lower limb of longitudinal ribs,and the maximum tension stress is less than the cracking stress of UHPC material.The steel-UHPC composite beams can greatly reduce the dead weight of structure and further reduce the section of the steel beam,which is expected to solve the problem of bridge deck cracking in the long-span continuous composite beam.