Dynamic analysis of the vibrations of the mechanical elastic systems using virtual instrumentation

The new slogan "The software is the tool" takes into consideration a new construction principle for the measuring tools and systems, with a brand new architecture. These systems and tools are assembled into a "virtual space" computer programming environment which provides such basic elements of construction. There is a big advantage of this type of measuring system: each human user can build himself an unlimited number of instruments intended to process and to analyze experimental data; these virtual instruments on the basis of dedicated computer applications can meet individual requirements designated to cover an extended domain of analysis. The function of data acquiring of the equivalent real instrument is now taking by a new PC peripheral (DAQ - data acquisition interface). The functions of data conditioning, data analysis and control are completely taken by the existing hardware in the computer and the software package in question. The current instrument system, as a whole, is designed and developed as a part of the computer, making possible the direct use of the computing power and the facilities of the PC. The article presents the virtual instrument developed on ICECON S.A. Bucharest on the basis of LabView (R) ver. 8.5 from National Instruments. The virtual instrument was used to acquire and to process some experimental data from the dynamic tests of the Bechtel viaduct at Km 29+602,75 <-> Km 29+801,25 on Romanian Highway A3 ("Transilvania" highway).