Data Procession And Analytical Study In Detection Of Bridge

With the continuous development of bridge construction, functions and formats of bridge become more complicated day by day. All kinds of abrasions of bridges will be watched after they have been used for years. Questions such as whether these wearing bridges could still be working and how long could they working are paid more attention. Therefore, detection and inspection of bridges have become one important guarantee that ensures safety maintenance and normal use of it. So, how to perform quality detection and safety inspection with bridges has become a research hotshot of foreign academia and engineering.First, this paper introduced several domestic and foreign breakdown accidents of bridge, the importance and necessity of bridge detection is then explained. Bridge detect is a new technique, many knowledge such as mechanics, structure, electronics, material and computer are involved. This paper introduced the actualities and developments of domestic and foreign bridge detect research. It is still a new research start in our country; there are still many problems to be solved. The oscillation characteristic of modern cable-stayed bridge, the abrasion mechanics parameters measurement and some normal techniques of bridge detect are involved in this paper; the oscillating frequency technique of cable' s mechanics detection is especially introduced, at the same time, its merits and disadvantages are discussed, some modifications measures are put forward. Following, some detecting instruments, such as resistance strain gauge, strain indicator and ondoscope, are introduced. The core instrument "sensor" is introduced with emphases. Sensor is an instrument that can distill useful information (normally coulometer) from quantum detected; the information distilled is often transformed into coulometer that can be transferred and dealt with easier. Sensors often used in bridge detecting are offset sensor, speed sensor and acceleration transducer, the last one is frequently used. Waveform detected from it is changed into offset waveform through two integral transformations, and then is transformed into spectrum graph or it is transformed into spectrum graph directly. Oscillating frequency of structure can be got from the spectrum graph. The static and dynamic characteristics of sensor are introduced in detail; the calibrations of first-order and second-order sensor' s parameters are discussed with two examples.Cable-stayed bridge is a kind of large-scale flexible-system bridge that is composed of lots of components, whose stress and distortion is affected by a lot of factors and the transformation disciplinarian of it is very complicated. In the process of detecting cable-stayed bridge, error of measurand between measured data and truth-value will inevitably be because of perfect detecting methods and detection instruments, affect of environments and deficiencies of detectors. To decrease error, we have to analyze the error factors of the antitype measuring data, confirm thecomposite error of measurand and understand the uncertainty evaluation of structure error parameters. To evaluate a bridge, we need identify structure parameters by real-time monitoring and analyze, evaluate actual macroscopical behaviors of it; we still need in virtue of diversifications of structure parameters relative to environments and diversifications during producing and developing of structure element' s crack, damage, corrosion. The understanding of structure parameters' diversifications rules relative to factors such as environments and structure performance recession is still too little; we still cannot confirm their certain relationships through theoretic deducing. Therefore, these parameters' coherent relationships are found by doing regression analysis to those parameters and their coherent condition factors; which is got through real-time monitoring an identifying. In the long process of real-time monitoring and analyzing, we should summarize and improve continually; from sensibility to sense, the deep objective laws of them are finally got. In...