基于未确知测度理论的桥梁结构耐久性评估

Durability Evaluation of Bridge Based on the Unascertained Measure Theory

根据各检测指标的评定标度,运用未确知测度理论建立各检测指标的测度函数;根据各部位检测数据建立外观裂缝、混凝土强度、碳化深度、保护层厚度、钢筋锈蚀的单指标未确知测度矩阵,并以每个指标各部位未确知测度的平均值作为该指标的未确知测度,形成多指标未确知测度矩阵;综合考虑各检测指标权重,求得桥梁结构的未确知测度,根据置信度识别准则对桥梁结构的健康状况进行评估.评估结果表明,该方法减小了桥梁耐久性评估中评估专家的主观性,使评估结论更具可信性,计算结果与其他方法相比具有较高的精度.

According to evaluation scale of measured index, the unascertained measure theory is used to build the unascertained measure function of single-index. Then, the unascertained measure matrix of fracture, concrete strength, carbonation depth, thickness of the protective layer and corrosion of reinforcement of every part are determined, the average value of the unascertained measure matrix of different part is used as the unascertained measure of this index, and the unascertained measure matrix of multi-index can be gotten. Finally, the unascertained measure of the bridge is calculated considering the index weight, and the health status of bridge structure is evaluated according to credible degree criteria. The proposed method can reduce the evaluation experts＇ subjectivity, and the evaluation result owns more credibility and more accuracy compared with existed method.