高墩大跨连续刚构桥施工控制参数敏感性分析

为研究高墩大跨连续刚构桥施工控制参数的敏感性,以贵州乌江特大桥为例,采用MIDAS Civil软件建立该桥三维有限元模型,计算施工监控过程中各主要参数的取值对结构线形和内力的影响.计算分析结果表明,混凝土节段重量、收缩徐变、温度荷载等参数对该桥施工控制精度有显著影响,混凝土弹性模量参数的影响比较明显,预应力参数敏感程度相对较低.在施工控制过程中,应及时收集节段混凝土容重、弹性模量等参数,根据实际施工时间历程考虑收缩徐变效应的影响,并对计算模型加以修正；在设置预拱度和监测数据测量时,要充分考虑到温度对桥梁的线形及应力的影响.

Analysis of Parameter Sensitivity of Construction Control of High-Rise Pier and Long Span Continuous Rigid-Frame Bridge

To study the parameter sensitivity of construction control of the high-rise pier and long span continuous rigid-frame bridge,a Wujiang River Bridge in Guizhou was cited as an example,the software MIDAS Civil was used to set up the three-dimensional finite element model for the whole bridge of the bridge and the influences of the selected values of all principal parameters in the process of the construction control on the geometric shape and internal forces of the structure were calculated and analyzed.The results of the calculation and analysis show that the parameters like the weight,shrinkage,creep and temperature load of the concrete segments have significant influence on the accuracy of the construction control,the influence of the parameter of the concrete elastic modulus is obvious and the degree of parameter sensitivity of the prestressing is relatively low.In the process of the construction control,the parameters of the unit weight and elastic modulus of the concrete should be timely collected and the model should be correspondingly updated in accordance with the construction time history and in consideration of the influence of the shrinkage and creep.When the precamber is set and the monitoring data are measured,the influence of temperatures on the geometric shape and stress of the bridge should be fully taken into account.