大跨双薄壁高墩连续刚构桥双悬臂施工状态非线性稳定分析  

NONLINEAR STABILITY ANALYSIS OF LONG-SPAN CONTINUOUS RIGID FRAME BRIDGE WITH DOUBLE THIN-WALL HIGH PIERS AT ITS CANTILEVER STATE

作　　者：方志[1] 王飞[1] 曹传林[2] 

机构地区：[1]湖南大学土木工程学院,湖南长沙410082 [2]湖北沪蓉西高速公路建设指挥部,湖北恩施445000

出　　处：《工程力学》2009年第7期155-162,共8页Engineering Mechanics

摘　　要：以龙潭河特大桥为工程背景,对双肢薄壁高墩连续刚构桥悬臂施工过程中各种工况下的稳定性进行了包括材料非线性在内的完全非线性分析,并对混凝土强度、薄壁墩厚度进行了参数敏感性研究。分析结果表明:在考虑双重非线性以后,高墩结构的稳定系数为仅考虑几何非线性解的60%;对变截面高墩而言,其破坏截面的位置与等截面高墩不同,不是位于墩底截面,而是出现在距墩底l/3(l为墩高)左右的区域;最大悬臂状态时,横向静风荷载对高墩稳定承载力会产生较大影响,当基本风速由18m/s增加到25.3m/s时,高墩的稳定承载力与不计横向风荷载相比,分别减少了14.06%及28.2%;混凝土强度和高墩壁厚对高墩稳定承载力影响显著;综合考虑各因素影响的非线性稳定分析具有更好的实际意义。Both geometrical and material nonlinear stability of high piers at the cantilever state are studied for the case of Longtan River Bridge. The effects of the wall thickness and concrete strength on the ultimate loading capacity are analyzed. It is concluded that the nonlinear stability number obtained in this paper is 60% of the one considering only the geometrical nonlinearity. The high piers with tapered sections fail at the locations of 1/3 pier height away from the pier bottom other than the bottom part as observed in the high piers with regular sections. At the maximum cantilever, the transversal static wind load has the great effect on the structural stability. When the basic wind velocity increases to 18m/s or 25.3m/s, the ultimate loading capacity of high piers decreases by 14.06% and 28.2% respectively. The concrete strength and wall thickness have significant impacts on the structural stability. Nonlinear stability analysis considering all effects is of great importance in practices.

关 键 词：稳定性 薄壁高墩 连续刚构桥悬臂施工非线性分析 

分 类 号：TU311[建筑科学—结构工程] U448.23[建筑科学—桥梁与隧道工程]