大跨度屋盖钢结构采用分块分步整体提升的施工工艺，施工过程中结构体系和边界条件存在突变，且整体提升为动态施工过程，整个过程结构的受力状态存在突变。针对整体提升等动态施工过程，基于时间序列一阶差分，提出应力和变形变化率指标；根据施工过程模拟结果和3σ准则，提出应力和变形的三级预警机制和预警阈值。对某K6网壳静力加载试验进行全过程构件应力和结构变形监测，并对监测结果进行分析和预警。结果表明，网壳结构在发生整体坍塌前，结构受力状态具有明显的非线性特征。提出的应力和变形变化率指标及预警机制能在网壳结构发生整体坍塌前，对受力状态的非线性变化进行有效预警，提醒使用人员提前做好应急措施。将提出的变化率监测指标和预警机制应用于上海松江站屋盖钢结构整体提升过程中，验证提出方法的可行性和有效性。结果表明，变化率指标及其预警机制，可对提升过程中的荷载和边界条件突变导致的结构受力性能突变有效预警，验证了本文提出方法的适用性。

The large-span steel roof structure adopts a segmented and stepwise overall lifting construction technique. During the construction process， there are sudden changes in the structural system and boundary conditions， and the overall lifting is a dynamic process with abrupt variations in the structural force state. In response to the dynamic construction process， including the overall lifting， stress and deformation change rate indicators are proposed based on first-order differences of time series. A three-level early warning mechanism and thresholds for stress and deformation are introduced based on simulation results of the construction process and the 3σ criterion. A monitoring of component stress and structural deformation was conducted during a static loading test on a K6 reticulated shell， with the monitoring results analyzed and used for early warning. The results indicate that before the overall collapse of the shell structure， there are clear nonlinear characteristics in the structural force state. The proposed stress and deformation change rate indicators， along with the early warning mechanism， can effectively warn of nonlinear changes in the force state before an overall collapse， allowing personnel to take emergencymeasures in advance. The proposed change rate monitoring indicators and early warning mechanism were applied to the overall lifting process of the steel roof structure at Shanghai Songjiang South Station to verify the feasibility and effectiveness of the proposed method. The results show that the change rate indicators and their early warning mechanism can effectively warn of abrupt changes in the structural force state caused by load and boundary changes during the lifting process， validating the effectiveness of the proposed method.