援马尔代夫中马友谊大桥主桥主梁方案比选

中马友谊大桥主桥为V形支腿六跨连续刚构桥,跨径布置为(100+2×180+140+100+60)m。根据桥址处实际工程条件,提出3种主梁方案:混凝土V构+叠合梁(耐候钢)方案、混凝土梁方案、混凝土梁+叠合梁(UHPC桥面板)方案,从结构受力、耐久性、施工难度和工期、经济性对3种方案进行对比分析。结果表明:混凝土梁+叠合梁(UHPC桥面板)主梁方案能有效减轻主梁自重、减小收缩徐变的不利效应、降低对基础受力的影响;结构耐久性较好、维护保养工作量小;施工工法灵活、工期有保障;经济性具有明显优势。因此,中马友谊大桥主桥最终选取混凝土梁+叠合梁(UHPC桥面板)方案作为主梁实施方案。

Comparison of Main Girder Schemes for Main Bridge of China-Maldives Friendship Bridge

The main bridge of the China-Maldives Friendship Bridge is a continuous rigid frame bridge which has a structure of V-shaped supporting legs and 6-span arrangement of (100+2× 180+ 140+100+60) m. According to the actual engineering conditions at the bridge site, three schemes of main girder are proposed as follows: a scheme of concrete V-leg rigid frame + composite girder (weathering steel), a scheme of concrete girder, and a scheme of concrete girder + composite girder (UHPC deck). The three schemes are compared and analyzed in terms of structural stress, durability, construction difficulty, construction period, and economy. The comparison results show that application of the main girder scheme of concrete girder + composite girder (UHPC deck) can effectively reduce the dead weight of the main girder, the adverse effect of shrinkage and creep, and the impair on the stress of foundation. The application of the scheme also has advantages of good durability in the bridge structure, small maintenance workload for the bridge, flexible method in construction, being able to guarantee the construction period and obviously high project economy. Therefore, the concrete girder + composite girder (UHPC deck) scheme is adopted to implement the construction of the main girder for the main bridge of the China-Maldives Friendship Bridge.