中文摘要：

宁波铁路南站主站房北立面为一个大型“水滴”钢结构造型,悬挑跨度16.3m、横向跨度66.0m、质量达154t、受力复杂、卸载难度大。为确保卸载安全,采用有限元软件分别对4种卸载方案进行卸载全过程仿真分析,得出“从中间往两侧对称卸载”的最佳方案,并确定38个应力监测点和18个变形监测点及其监测预警值。利用MATLAB程序实时计算各测点的实测值,判断其变化趋势,指导现场卸载操作。监测结果表明：应力和变形实测时程曲线基本被仿真曲线包络,实测值和仿真值变化趋势基本一致,北水滴钢结构卸载过程安全可靠;该卸载监测方法科学、实施有效。

英文摘要：

The water-drop shape steel structure was located in the north elevation of Ningbo South Railway Station, whose cantilever span is 16.3 meters, transverse width is 66.0 meters, the weight is 154 tons, stress is complex, which was difficult to unload. To ensure unloading safety, the symmetrical unloading from the middle to both sides was selected as the best unloading scheme from 4 unloading schemes by the whole unloading process simulation, the 38 stress monitoring points and the 18 deformation monitoring points and the early warning value in different stages are confirmed. The measured value of each point timely is calculated by MATLAB program, the variation trend is judged, and the unloading operation on site is guided. The monitoring results demonstrate that, the measured time history curves of stress and deformation are enveloped by simulation curves basically, the change tendency of measured value and simulation value are consistent basically, the unloading monitoring scheme is scientific, and implementation is effective.