CAJ | 학술논문

新白沙沱长江特大桥主桥3＃墩承台有1/3位于江中突出的岩石岛礁上，爆破后承台的上下游和江中一侧都是较陡的倾斜岩面，江水洪枯水位落差达15 m，且仅距上游老白沙沱铁路桥130 m，施工条件困难。针对主墩基础施工平台和围堰，重点研究了先围堰后平台双壁钢围堰整体浮运和先浮运提升形成平台后施工围堰两个方案。从施工方法、安全性、工期、经济性等方面进行比选，结果表明，选用先平台后围堰方案更适合实际情况，既可保证安全与质量，又可缩短工期，减少成本。
신백사타장강특대교주교3＃돈승태유1/3위우강중돌출적암석도초상，폭파후승태적상하유화강중일측도시교두적경사암면，강수홍고수위락차체15 m，차부거상유로백사타철로교130 m，시공조건곤난。침대주돈기출시공평태화위언，중점연구료선위언후평태쌍벽강위언정체부운화선부운제승형성평태후시공위언량개방안。종시공방법、안전성、공기、경제성등방면진행비선，결과표명，선용선평태후위언방안경괄합실제정황，기가보증안전여질량，우가축단공기，감소성본。
In the study of the new Baishatuo Yangtze River bridge , it is noticed that one third of the bearing platform on the 3# main bridge pier is set on the rock reef amidst the river .After the blasting , cliffily oblique rockface forms the upper and lower reaches , as well as one river side that surround the platform.The drop height of the river achieves the level of 15 m,and the bridge stands only 130 m away from the old Baishatuo railway bridge upstream .Therefore the construction is proceeded under difficult conditions.The paper focuses mainly on two parts , namely the foundation construction platform on the main pier and the cofferdam .Under this framework , it proposes two possible schemes-starting with the floatation of the double-walled steel cofferdam, then the construction of the platform; or alternatively, starting with the platform and then the cofferdam .The paper discusses the feasibility of both solutions from the perspectives of construction method , safety , required time period and cost .The results indicate that the latter is more reliable in terms of safety ,quality,construction period and cost .