【摘要】 桥梁转体施工中保证转动体系重心位于转轴中心较小的范围以内对顺利转体十分重要,表现为转动体系以转轴中心的刚体不平衡力矩尽量小。然而实际施工中不可能做到转轴中心两侧完全对称,特别是转体前采取支架现浇方式施工的桥梁均存在不同程度的不平衡力矩,需要通过一定方法进行不平衡力矩测试,用于转体前的配重设计。探讨了转动体系不平衡力矩的测试方法,提出了利用墩柱应变(应力)检测不平衡力矩的方法,并以实际某转体桥梁为实例,采用上述测试方法与转动体系称重试验结果进行了对比,结果显示利用墩柱应变(应力)检测不平衡力矩方法可以准确地获得转动体系偏心大小。方法简便易行,可大大减少称重所需的人力物力投入,节省施工时间,为今后转体施工不平衡力矩测试提供借鉴。更多还原

【Abstract】 Center bearing is very important to the smooth rotation in swivel bridge construction.And the center bearing is that the center of gravity of rotation system through the center of shaft,which is manifested as the moment balance control of symmetrical rotary center in longitudinal and transverse direction. In the process of construction,even self-balancing rotation system is also impossible to make the spheric hinge completely symmetrical on both sides,and especially for the cast-in-place bridges by using the way of support before swiveling,then the unbalanced moment exists. So there must be an unbalanced moment test before swiveling,and then make counterweight design according to the results. This paper discusses the methods presently used for the unbalanced moment testing of rotation system and improves a unbalanced moment testing method by using pier strain( stress). Then a comparison between various methods with the results of weighing test is made by taking an actual twist bridge as an example. The results show that the proposed unbalanced moment testing method can accurately predict the offset of the rotation system. This method is simple and easy,can greatly reduce the manpower required for the weighing investment,save construction time and provide reference for the future unbalanced moment test.更多还原