【摘要】 为了在工程现场快速方便地检测斜拉桥的拉索索力,依据随机振动法索力检测原理,开发了一种新型的索力测量系统。通过对随机振动法索力检测方法的概述,介绍了该系统的性能、硬件结构和软件模块,并重点阐述了通过数字滤波抑制快速傅里叶分析(FFT)的混频现象、自动扫描确定主振频率和提高索力计算精度的方法和措施。索力测量系统以AT89C55WD单片机(SCM)为平台,集成了电荷放大器、信号分析仪和计算器的相关功能。在工程现场,只需输入少量参数,拉索振动信号采集、信号的快速傅里叶分析和对应的索力计算即可在线自动完成。更多还原

【Abstract】 In order to measure the cable tensions of a cable-stayed bridge quickly and conveniently at a construction site,a new measuring system of cable tension was developed according to the random vibration frequency method. With summarizing the principle of the random vibration frequency method,the function,hardware construction and software module of this system were introduced.The ways and means to solve some key technical problems were discussed emphatically using digital filter to restrain frequency confusion of FFT,scanning and confirming main frequency of a vibration signal,and improving calculation precision of a cable tension.The system was based on an AT89C55WD SCM.The functions of a charge amplifying,a signal analyser and a calculator were integrated in an instrument.After a few parameters were inputted,the collecting vibration signal,the FFT of the signal and the estimating cable force could be carried out automatically on line at a construction site.更多还原