基于桥梁的极值应力监测信息,采用贝叶斯动态线性模型(BDLM),建立了监测应力的贝叶斯动态线性组合预测模型;采用该模型对结构的可靠指标进行实时预测,并通过工程实例进行了极值应力的组合预测和单个预测的精度分析.结果表明:所建立的组合预测模型的一步预测值与单个预测模型、取平均值的点预测模型的都很接近,但组合预测模型具有较高的预测精度;相对于确定性的监测极值应力的可靠指标而言,组合预测模型考虑了监测应力的随机性和不确定性,所得的可靠度较小,可以更好地对结构的安全状态进行评定.
Based on the monitored extreme stress of bridges, a combinational forecasting model of extreme stress is constructed with the Bayesian dynamic linear model (BDLM). Then, the proposed model is used to forecast the structural reliability indices in real time. Moreover, a project case is provided to analyze the forecasting precisions of the combinational forecasting model and the existing single forecasting models. The results show that, though the proposed model is of an one-step forecasting value close to that of the single forecasting models and the mean point forecasting model, it is of higher forecasting precision, and that, as compared with the deterministic reliability indi- ces for extreme stress monitoring, the combinational forecasting model fully considers the uncertainty and random- ness of monitored stress and helps to obtain smaller reliability indices, so that it is more effective in forecasting the structural safety.