【摘要】 桥梁结构被破坏的重要原因之一就是水流对桩基的冲刷使桥墩附近的基础被逐渐冲蚀,桥墩通常对于水流起阻碍作用,进而导致在桥墩附近水流流速过快并产生漩涡,冲蚀桥墩附近基础,使桥梁处于不安全的状态。由于河流冲蚀对桥梁造成的破坏已经成为世界关注的焦点。目前的桩基冲刷监测方法如人工深度尺、声纳、雷达和时域反射计(TDR)等有离线、精度低、稳定性差、成本高和传感元件耐久性差等缺点,难于实时、准确监测桩基的冲刷状态。文中提出了一种通过监测桩基附近土压力大小进而分析桩基冲刷状态的新型冲刷传感器,敏感元件选取光纤光栅(FBG),光栅的封装采用经过结构优化设计的GFRP悬臂梁,在此基础上制作出适合实际工程应用的光纤光栅桩基冲刷监测传感器,同时通过大量的实验验证了这种传感器的传感性能,其空间分辨率达0.1 m.更多还原

【Abstract】 Local scour to the pier footing is one of the most serious factors for the bridge failure.Bridge piers often obstruct the flow of floodwaters,causing an increase in velocity and the development of vortices.The increased velocity and vortices often cause scour near the bridge foundations.The damage to bridges caused by scour are problems of international concern.The common methods such as sonar,radar,time domain reflectometry(TDR)are difficult for the real time local sour monitoring because of its bad surroundings around the piers.A new kind of FBG souring sensor for the local scour was indicated.FBG was encapsulated in GFRP cantilever beam and the structure of the sensor was optimized by Ansys software.Then groups of experiments were carried out to validate the characters of the sensor.The space resolution of the sensor is up to 0.1 m.更多还原