Study And Implementation Of Long Span Cable-supported Bridge Deflection Measurement System Based On DSP

As one of the leading parameters in reflecting the health of a bridge's construction, the deflection of a bridge has been always studying by the bridge professionals, and hence many measurements are put forward and working practicably. Among of those measurements on the deflection, especially upon a long span bridge, a measuring instrument of joint-hoses enjoys a good comment as much measuring points, weak-influenced by the surroundings. But it still meets a weakness of manual measuring, lower accuracy, slower speed and so on. Therefore, we take it up to apply an advanced photoelectric technology into the joint-hoses instrument in order to improve its performance. We finally developed an automatic measuring system of the bridge's deflection to meet the needs of long-term on-lined, auto-measuring upon the deflection measuring of the big-spanned bridge. It must have an important theoretical meaning and practical value.This thesis is firstly to set up a mechanical model and to deduce the formula of bridge's deflection, and then to analysis the distribution of the bridge's deflection in order to provide the theoretic evidence of identifying the distribution of the deflecting points and the measuring range. Secondly, we designed and made a special sensor on measuring the deflection, which is aiming at the characters of the deflection measuring upon the big-spanned bridge. We adopted TI's IC of TMS320C32 as the processor of this measuring system, to complete the data's collecting and processing, by means of the interface with the memory's extension and analogical-digital transforming circuit. We utilized the standard of RS-485 to accomplish the signal's remote conveying and communication. We also utilized the Watchdog technology to accomplish the supervisory control against the circuit and to ensure the system's stable running. We have achieved the system's development both of the hardware and software in our laboratory, and hence solved a number of problems during the system. We finally build up the measuring system of the bridge's deflection, carry out all the system's rectifying and testing, and track the measuring results by means of theoretical analysis and data processing.To our satisfaction, all the testing results could proof this measuring system of the bridge's deflection is convincing, and accurate. It could meet the demands of measuring upon the bridge's deflection...