Analysis Of Mechanical Properties Of Steel Boxed Cofferclarn Structure And Environmental Load Limit State

In recent years, bridge design and construction in China have achieved leapfrogdevelopment, and the bridge construction technology with long span and deep waterfoundation has ranked among the world’s advanced countries. The construction ofbridge, especially the deep water foundation has complex processing with high contentof technology. Our bridge workers have made remarkable achievements in many aspectslike research, design and construction. Besides, with the development of deep waterfoundation construction techniques and machines, the application of cofferdamstructures is spreading increasingly.The double-wall steel boxed cofferdam is a common type in the bridgeconstruction of deep water foundation with advantages of great stiffness and integrity,which can provide larger space for platform construction and offer support condition fortop construction platform.This article takes the main continuous beam bridge Pier062#～066#of the NorthBranch of the Wuhan Tianxingzhou Yangtze River Bridge as the background, so as tomodel and make simulation analysis about the steel boxed cofferdam by Midas-civilthree-dimensional finite element software. Having considered the influence ofhydrostatic pressure, flowing water pressure, wind load and wave load, the load on thesteel cofferdam complies with that in the real environment in the simulation calculation,thus, the internal stress and strain field results will be more accurate.This article concentrates on three dangerous working conditions of the steelcofferdam, simulates and analyzes different water levels under Condition1, Condition2and Condition3, in order to judge the safety of the steel cofferdam and find the mostdangerous condition. In addition, the article also analyzes the external environment loadlimit state under different conditions to find out the external environment load (waterpressure, wind load and wave load) that can be sustained by the yield steel cofferdamstructure under the least favorable condition, and figure out the scale factor of thedesigned external environment load value.We can see from the whole article that the design of the steel cofferdam structure isstill conservative and possesses stable reserves even under the least favorable condition.Therefore, the later designs are expected to achieve a balance between the structuralsafety, stability and economic effects. Moreover, the scale factor of the externalenvironment load value has certain significance for the further design and therecommended value is1.5-2.0.