基于振弦传感技术的高性能锚索测力系统开发研究

RESEARCH AND DEVELOPMENT ON HIGH PERFORMANCE ANCHOR CABLE DYNAMOMETRIC SYSTEM BASED ON VIBRATING-WIRE SENSOR TECHNOLOGY

预应力锚索锚固工程中迫切需要性能优异的锚索测力系统,以便能够锚索施工过程中进行张拉力控制以及其在时间作用下的锚索锚固力长期变化情况进行监测。通过理论研究、实验室研究和现场工程试验研究,开发基于振弦传感技术的高性能锚索测力系统,取得了突破性研究成果:(1)建立新数学模型,可提高传感器准确度并能够进行温度误差补偿;(2)采用弦与工作膜匹配技术,减小了滞后同时提高了进程精度;(3)采用弱激发电路技术,解决了频率不一致问题并提高了测量仪器的分辨率;(4)采用活塞传压与力变换技术,解决传感器的大量程、偏载影响、准确度和长期稳定性问题,适用于研制大量程、高精度、高分辨率和长期稳定性好的测力传感器;(5)配套检测仪器,可直接显示所测物理量,不产生附加误差可提高传感器准确度。所研制的锚索测力系统在准确度、大量程、偏载、稳定性、可靠性以及环境适应性等方面达到了国际领先水平,可为预应力锚索受力状态实时监测提供技术支持。

Outstanding anchor cable dynamometric system is urgently needed in anchor engineering of pre-stressed anchor cable so as to control tension during the process of anchor cable construction and monitor long-period variation of anchoring force.A breakthrough research has been made on the development of high performance anchor cable dynamometric system based on vibrating-wire sensor technology through theoretical research,laboratory study and field engineering experiment research.Here are the research results：（1） The newly-built mathematical model can improve the accuracy of vibrating-wire sensor and make error compensation for temperature.（2） The matching technique of string and operating diaphragm was adopted so that lag was decreased and accuracy of process was improved.（3） The low excitation circuit technology has been put into use that the inconformity of frequency was solved and the resolution of measuring instruments was enhanced.（4） The techniques of piston-conveying pressure and force conversion technology has been used to solve the vibrating-wire sensor problems of wide range,partial load effect,accuracy and long-term stability,which can be used to develop vibrating-wire sensors characterized with wide range,high-accuracy,high resolution and long-term stability.（5） Supporting detecting equipments,can directly display the physical quantity without additional errors but more accuracy.The newly developed anchor cable dynamometric system has achieved international leading level at aspects of accuracy,wide range,partial load,stability,reliability and environmental suitability that it can offer technical support for real-time monitoring of stress condition of pre-stressed anchor cable.