深水基础双壁钢套箱围堰结构力学性能分析

An Analysis of the Mechanical Performances of the Structure of a Double-Walled Steel Cofferdam for the Deep-Water Foundation

双壁钢套箱围堰因其刚度大、整体稳定性能强以及适应深水环境等优点被广泛应用于大型桥梁深水基础施工,但是由于双壁钢套箱围堰自身结构的复杂性以及所处位置具有水位深、地质不良等特点致使其受力情况更加复杂,因此,为了确保结构的设计合理并考虑施工的不安全因素,有必要对双壁钢套箱围堰进行整体结构受力分析。以一座双塔双索面五跨钢桁梁斜拉桥P7墩深水基础双壁钢套箱围堰为研究对象,运用MIDAS软件对其结构的力学性能进行有限元分析,根据双壁钢套箱围堰在不同工况下结构应力、变形以及稳定性的分析结果提出合理的施工要求及建议,进而保证施工安全顺利进行。

Having the advantages of being great in rigidity, powerful in overall stability, and suitable for deep-water environ-meritthe double-walled steel cofferdam is widely applied to the construction of deep-water foundation of large-type bridges. However, owing to the complexity of the structure of the double-walled steel cofferdam and its characteristics of being located in deep water and unfavorable geological strata,the load-bearing circumstances of the double-walled steel cofferdam are even more complex. Thereforein order to ensure the rationality of the design of the structure and the security of construction, a stress analysis has to be made of the whole structure of the double-walled steel cofferdam. With the double-walled steel coffer-dam for the deep-water foundation of the P7 Pier of a double-tower, twin-cable-facefive-span-steel-truss girder cable-stayed bridge as the object of our studies,a finite element analysis is made of the mechanical behavior of the structure with the MIDAS software in the paper upon the basis of which the reasonable construction requirements and suggestions are put forward in the light of the analysis results of the structural stressdeformation and stability of the double-walled steel cofferdam under differ-ent working conditions. As a resultthe safety of the construction is thus ensured.