光纤Bragg光栅传感检测组合结构的断裂损伤

采用光纤Bragg光栅(FBG)传感器对钢-混凝土组合桥面板模型由加载产生的滑移、掀起(脱空)和裂缝三类损伤进行检测。试验经历了静载、300万次循环疲劳加载和破坏三个阶段。结果表明在静载和疲劳试验阶段未出现滑移、掀起和纵向裂缝,传感器测得FBG布控处的混凝土应变值。破坏阶段中,组合结构相继出现裂缝、滑移和掀起损坏,利用FBG传感器测到发生此三种损坏的临界应变值并追踪其发展。结果表明:光纤Bragg光栅(FBG)传感器能够检测组合结构的断裂损伤,并追踪其发生发展的全过程。该技术对组合结构的健康检测和优化设计是很有用的。

FRACTURE MONITORING OF STEEL-CONCRETE COMPOSITE STRUCTURE USING FBG SENSING

Fiber Bragg grating(FBG)sensors are used to monitor fractures including slips,disengages and cracks of steel-concrete composite structure model.The test undergoes three phases:dead load test phase,fatigue test phase(3×106 cycles),and destructive test phase.The results show that no fracture occurred during the first two phases.The data measured were the concrete strain of the location where the FBG sensor embedded.During the destructive test phase,structural cracks,slips and disengages occurred one after another and were measured by the FBG sensors.The critical strain values of the three kinds of damages were detected.The results demonstrate that the fractures of composite structures and their development processes can be detected and traced by means of FBG sensors,thereby this technique is useful for the health monitoring and optimal design of composite structures.