| Along with the bridge structure constantly incline to large and complicated, thetraditional artificial detection method can not fully meet the security needs of large spanbridges, so health monitoring mehod is becoming a more and more important technical meansthat can secure bridge operation safety.The comprehensive background data acquisition ability and the refined front desk dataperformance ability together determine the scientific guiding value of a bridge healthmonitoring system, but in most current health monitoring systems the data collection capacityis far better than the data expression.Although most of current health monitoring systems can collect mass data continuously,but the study of importance, regularity as well as correlation of health monitoring data is stillnot deep enough, so that a lot of monitoring data can not get proper treatment and usage, massdata on the contrary become a bottleneck of health monitoring system and restricted healthmonitoring system to play its scientific guiding significance.Therefore, in view of the characteristics of mass health monitoring data, the study of dataprocessing cycle and the processing method is of great significance.This paper, based on “The long-term health monitoring system of Xinguang Bridge” forengineering background, studied the data processing cycle and processing method of bridgehealth monitoring system, which is applied to the health monitoring data processing ofXinguang Bridge that include temperature data, wind data, static stress data, vibrationdata,suspender force and deformation data.This paper can also provide a accurate and reliable data support for the follow-up healthassessment.The main work of this paper is as followed.(1) Based on a summary of the present situation and development of the bridge healthmonitoring system and its data processing method in recent years at home and abroad, thispaper introduced the health monitoring data processing cycle and the data processing methodof Xinguang Bridge. (2) The environment load monitoring data processing of Xinguang Bridge:Based on the actual measured temperature data of Xingguang Bridge, this paper doingstatistical analysis to the measured effective temperature, the actual temperature field of steelarch ribs and other temperature load parameter values that is required by rules and regulationsin the design codes; this paper also processed the wind load data of Xinguang Bridge,statistically analysed the average wind characteristics which includes10minutes maximumsustained wind speed and Wind rose, statistically analysed the fluctuating wind characteristicswhich includes average wind speed, turbulence intensity, turbulence integral scale andfluctuating wind power spectral density function.(3) The structural response monitoring data processing of Xinguang Bridge:Based on the measured static strain data of Xinguang Bridge, this paper has done a workon data transfer, reliability test, stress separation, etc. This paper also proposed the adaptiveabnormal data elimination algorithm of Xinguang Bridge. By employing correlation analysismethod and regression analysis method, data processing method this paper separated thetemperature stress, constant stress and random live load stress from the total stress.Based on the measured vibration data of Xinguang Bridge, this paper adopted the Ppmethod and the SSI method to identify measured modal parameters of Xinguang Bridge thatinclude natural frequency, mode damping ratio and vibration model.Based on the measured suspender vibration data of Xinguang Bridge, this paper adoptedthe frequency method to calculate the suspender force of suspenders and proposed a set ofadaptive suspender force automatic calculation method so as to realize the automaticcalculation of suspender force.Based on the measured GPS deformation data of Xinguang Bridge, this paper processedthe following data which include baseline nets results calculation, coordinates transformation,gross error output and smooth processing so as to obtain the deformation of Xinguang Bridge.(4) Based on the data processing procedure and method introduced above, this paperdeveloped a monitoring and control software as well as a data query and statistical analysissoftware for the Xinguang Bridge health monitoring system. The main conclusions of this paper are as followed.(1) The actual temperature of steel arch ribs at each different locations on XinguangBridge are obviously different, but the design only considered overall temperature rising andcooling effect. So in the follow-up teperature load correction of whole bridge componentcarrying capacity assessment should take the influence of integral temperature rising andcooling effect as well as local temperature difference in to account.(2) The measured10minutes maximum sustained winds of average level of XinguangBridge is low, and have a large difference with the design wind speed value; The measuredturbulence intensity mean value at Bridge deck height is lager than the standard recommendedvalue, while the measured turbulent integral mean value is smaller than standardrecommended value, and the measured longitudinal wind power spectrum is consistent withthe standard recommended Simiu spectrum.(3)The adaptive abnormal data elimination algorithm of Xinguang Bridge based onsample data can effectively eliminate the abnormal monitoring stress data; The stressseparation algorithm can effectively separate the constant load stress, temperature stress andrandom live load stress; From the processing result of measured stress data, the constant stressaccounts for a large proportion of the total stress in Xinguang Bridge, and the temperaturestress predominante the total stress change, the random live load stress have little influence onthe total stress change.(4) The Pp method and the SSI method have relatively high reliability in naturalfrequencies and modal shape recognition of Xinguang Bridge, and the SSI method is betterthan the Pp method for damping ratio calculating, the calculation result of Pp method is notperfectly reliable. From the measured vibration data processing result, the natural frequencyof Xinguang Bridge is in great agreement with the theoretical value, and can identifyrelatively high levels of natural frequency and vibration mode.(5) The proposed adaptive suspender force automatic calculation method of this paper isapplicable to suspender force monitoring of bridge structure during operation period withrelatively smooth suspender force change. |
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