NRS下多证据融合的混凝土桥梁耐久性评估模型  

Durability assessment model of concrete bridge based on multi-evidence fusion under NRS

作　　者：张永良 郑大为[1] ZHANG Yongliang;ZHENG Dawei(School of Civil Engineering,Liaoning Technical University,Fuxin Liaoning 123000,China)

机构地区：[1]辽宁工程技术大学土木工程学院,辽宁阜新123000

出　　处：《中国安全科学学报》2023年第1期169-176,共8页China Safety Science Journal

摘　　要：为准确评估混凝土桥梁的耐久性,提出基于邻域粗糙集(NRS)与D-S证据理论的评估模型。首先,根据混凝土桥梁的结构特征,构建耐久性评估指标体系,并建立起耐久性评估数据库;其次,结合数据库,采用NRS的上下近似定义,确定不同评估指标的基本信度分配,并基于各指标的综合权重构造证据折扣因子,实现对初始基本信度分配的修正;然后,通过D-S证据理论合成规则进行融合,得出耐久性状态等级命题的置信度,进而根据最大隶属原则确定耐久性状态等级;最后,以多座在役混凝土桥梁的实测数据进行算例验证。结果表明:利用该模型获得的耐久性评估结果与现场实测结果一致,相较于传统的评估模型,该模型不仅能更准确地评估混凝土桥梁的耐久性,而且,能通过置信度反映耐久性的劣化趋势,这可为混凝土桥梁的维修加固、养护提供参考依据。In order to accurately evaluate the durability of concrete bridges,an evaluation model based on NRS and D-S evidence theory was proposed.Firstly,according to the structural characteristics of concrete bridges,the durability evaluation index system was constructed,and the durability evaluation database was established.Secondly,combined with the database,the basic reliability distribution of different evaluation indexes was determined by using the upper and lower approximation definition of NRS,and the evidence discount factor was constructed based on the comprehensive weight of each index to realize the correction of the initial basic reliability distribution.Then,through the fusion of D-S evidence theory synthesis rules,the confidence of durability state grade proposition was obtained,and then the durability state grade was determined according to the maximum subordination principle.Finally,the measured data of several existing concrete bridges were used to verify the example.The results show that the durability evaluation results obtained by this model are consistent with the field measurement results.Compared with the traditional evaluation model,it can not only evaluate the durability of concrete bridges more accurately,but also reflect its deterioration trend of durability through confidence,which can provide an objective reference for the maintenance,reinforcement and maintenance of concrete bridges.

关 键 词：邻域粗糙集(NRS) 混凝土桥梁 耐久性评估 基本信度分配 综合权重 D-S证据理论 

分 类 号：X913.4[环境科学与工程—安全科学] U447[建筑科学—桥梁与隧道工程]