基于健康监测系统的钢箱梁桥疲劳可靠性及车流量优化管理研究

项目名称： 基于健康监测系统的钢箱梁桥疲劳可靠性及车流量优化管理研究

项目编号： No.51308073

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 建筑科学

项目作者： 邓扬

作者单位： 长沙理工大学

项目金额： 25万元

中文摘要： 钢箱梁桥焊缝的疲劳开裂是工程中较难解决的问题之一。利用应变监测数据开展在役钢箱梁桥疲劳评估已成为国内外的研究热点，但由于结构自身的复杂性及应变测点数量的限制，有限的应变监测数据难以满足实际需要。 本项目综合运用应变和桥址车辆荷载的监测数据，开展在役钢箱梁桥的疲劳可靠性评估及车流量优化管理研究，研究内容包括：（1）研究钢箱梁典型焊接构件焊缝周围应力场的分布规律，分析应变传感器测点应力与焊缝名义应力的关系，获取两者之间的空间调整系数，提出焊缝疲劳应力确定方法；（2）依据动态称重系统监测数据建立车载概率模型，并采用应变监测数据对车载概率模型进行修正和验证，在此基础上提出焊缝细节疲劳荷载效应的随机模拟方法；（3）揭示车辆荷载对焊缝细节疲劳可靠度的影响机理，建立疲劳可靠度与车流量的相关性模型，探索基于疲劳可靠度的超重车流量优化管理方法。研究成果可为桥梁结构健康监测数据的工程应用提供新的思路。

中文关键词： 钢箱梁；疲劳可靠度；结构健康监测；名义应力；动态称重系统

英文摘要： Fatigue cracking in steel box girders has been one of the difficult issues in bridge engineering. At present fatigue assessment based on strain monitoring data has become a research hotspot for in-service steel box girder bridges. But due to structural complexity and limited strain sensors, the strain monitoring data from limited strain sensors is still unable to meet the needs of fatigue assessment. So in this project both the strain data and vehicle loading data collected by structural health monitoring system will be utilized for fatigue reliability assessment and optimization management of vehicle flow for steel box girder bridges. The main content of this project is as following. (1) The stress field distribution around the welds will be investigated for the classic welded components of steel box girder. The relation between stress measured by strain sensors and nominal stress of welds will be analyzed. Accordingly, the spatial adjustment factor between measured stress and nominal stress will be calculated and the method to determine the fatigue stress of weld details will be presented. (2) The probability model of vehicle loads will be established based on Weigh-in-Motion system, which is usually installed as a part of the structural health monitoring system. Then the probability model of vehicle loads wil

英文关键词： steel box girder；fatigue reliability；structural health monitoring；nominal stress；weigh-in-motion system