基于智能复合材料加固的桥梁疲劳寿命估计及时变可靠性研究

With the rapid development of China's transport undertaking, the fatigue damage because of vehicle repeated loading has became one of the main mode of bridge structural failure. The reliable methods for monitoring fatigue state of bridge and fatigue life estimation are the scientific problems urgent need to solve, also are the social issues affect people's lives. By taking the reinforced concrete simply supported beam bridge as research object, the smart composites will be invented based on fiber reinforced polymer composite and optical fiber Bragg grating sensing technology. The independent development tension device was invented and RC beams strengthened with prestressed smart steel strands and smart CFRP plates will be tested to establish the numerical model of the strengthened structure. Incidence relation of structural stress state-CFRP strain will be established to evaluate the fatigue life and time-dependent reliability of the strengthened bridge based on long-term monitoring data. The research results can provide a new technique for bridge strengthening and monitoring, also provide the theoretical guidance for durability assessment of bridge.

随着我国运输事业的飞速发展，车辆反复荷载引起疲劳累积损伤成为桥梁结构失效的主要模式之一。采用可靠的方法对既有桥梁疲劳状态进行有效监测及寿命估计是亟待解决的科学问题，也是关乎人民生命安全的社会问题。本项目以混凝土简支梁桥作为研究对象，在纤维增强复合材料和光纤光栅传感技术的基础上研发具有自监测性能的智能加固材料。利用自主研发的锚具及张拉设备，完成预应力智能钢绞线和智能碳纤维板加固混凝土梁疲劳试验研究，建立数值计算模型。建立结构受力状态-CFRP应变之间关联的数学表达，基于长期监测数据评估被加固结构的疲劳寿命及时变可靠性。其研究成果不仅能为桥梁加固及健康监测提供一种新技术，还为加固桥梁结构的耐久性评定提供理论指导。

随着我国运输事业的飞速发展，车辆反复荷载引起疲劳累积损伤成为桥梁结构失效的主要模式之一。采用可靠的方法对既有桥梁疲劳状态进行有效监测及寿命估计是亟待解决的科学问题，也是关乎人民生命安全的社会问题。. 本项目以混凝土简支梁桥作为研究对象，在纤维增强复合材料和光纤光栅传感技术的基础上研发具有自监测性能的智能加固材料。利用自主研发智能CFRP板，完成智能CFRP板加固混凝土梁疲劳试验研究及智能CFRP板加固混凝土梁疲劳剩余强度试验研究。建立了结构受力状态-CFRP应变之间关联的数学表达，基于长期监测数据开展被加固结构的疲劳寿命评估及时变可靠度研究。其研究成果不仅能为桥梁加固及健康监测提供一种新技术，还为加固桥梁结构的耐久性评定提供理论指导。. 项目按照原计划完成全部内容，并在智能CFRP板加固受损钢结构疲性能研究以及CFRP板加固混凝土结构的应用领域进行了有益的探讨。