基于离散灰色优化模型的大温差梁挠度预测模型研究

Research on Deflection Prediction Model of Composite Beams with Large Temperature Difference Based on Discrete Grey Optimization Model

为定量表征大温差、强风环境下钢混组合梁桥关键施工工序挠度变化规律,以新疆木垒县博斯坦乡首座钢混组合梁桥为研究对象,考虑环境因素的影响,分析组合梁体吊装前后关键阶段位移变化规律,同时基于有限元理论模型和实测值,建立GM(1,1)和OMGM(1,1)两类灰色预测模型,对其进行残差、关联度、后验差精度检验.结果表明:两类模型具有较高的精确度,均满足钢混组合梁桥位移预测要求,可对吊装阶段梁体位移进行预测推演.相比GM(1,1)模型,OMGM(1,1)模型精度更高,建议将OMGM(1,1)模型作为桥梁关键工序施工前的挠度控制分析检验公式,以提高预测精度.

In order to quantitatively characterize the deflection variation law of key construction procedures of composite beam bridge under large temperature difference and strong wind environment,taking the first composite beam bridge in Bostam,Mulei,Xinjiang as the research object and considering the influence of environmental factors,this paper analyzes the variation law of beam displacement before and after the hoisting of composite beam.At the same time,based on the finite element theoretical model and the measured value,two kinds of grey prediction models GM(1,1)and OMGM(1,1)are established,and their residual,correlation and posterior error accuracy are tested.The results show that the two models have high accuracy and both meet the displacement of composite beam bridge.Compared with GM(1,1)model,OMGM(1,1)model has higher accuracy.It is recommended to use the OMGM(1,1)model as a deflection control analysis and verification formula for key bridge construction processes to improve prediction accuracy.