Research On Short-term Monitoring Sensor Optimization And Safety Warning For Continuous Beam Bridge

China has built abundant large and medium-sized bridges to fulfil the requirements of transportation.With vigorously facilitate the economy of the state to promote domestic traffic flow across the elevator,At the same time,the operating bridges have problems such as overloading of vehicles and untimely maintenance,leading to potential safety hazards after damage to large and medium-sized bridges during operation.However,most of these bridges have the problem of insufficient inspection funds,making it difficult to carry out long-term monitoring.Therefore,we require to adopt a more short-term economic health monitoring to determine the bridge.This paper focuses on short-term monitoring,taking a prestressed concrete continuous beam bridge as the research object,combining the characteristics of short-term monitoring,and conducting research on the optimal arrangement of transducers fit for short-term monitoring for several types of transducers,and various early warning indicators of early warning safety study varying degrees of red and yellow.The research is as follows:Bridge structure associated optimal sensor standards and methods are summarized,from early warning indicators,early warning threshold value,warning level and warning process in four areas of security warning to elaborate.The application of effective independent method,modal confidence criterion,genetic algorithm and sequence method in bridge health monitoring is briefly described.Taking a domestic girder bridge as the study example,damage of the bridge were counted.A numerical model was established according to the data of he monitored beam bridge,and the bridge operated analysis and calculation of modal.The acceleration measurement points,strain measurement points and deflection measurement points were optimized by effective independent algorithm based on distance coefficient,stepwise accumulation method,genetic algorithm and Chebyshev polynomial zero points,respectively,and the final short-term monitoring point layout scheme was determined.In the short-term monitoring process,due to the influence of the external environment or the change of the monitoring equipment,the collected data deviates from the real data,and the phenomenon of data distortion occurs.Combined with the massive data obtained from this short-term monitoring,it is concluded that there are three main types of data distortion common in short-term monitoring data:single-point data distortion,continuous data distortion,and data missing.For disparate types of distortion information,corresponding identification and disposing methods are proposed according to their characteristics to realize the preliminary processing of monitoring data and provide more effective data for subsequent safety warnings.Combining the calculation results of the finite element model of the bridge,and analyzing the key information between each data,a set of continuous beam bridge safety early warning system based on short-term monitoring is comprehensively established from three levels of single value,single section and multi-section.