Research On Dynamic Deflection Monitoring Precision Feature Of Pipe In The Pressure Field

The automation?real-time and accurate monitoring of the dynamic deflection of the bridge has a very important significanceis for the safe operation and reasonable management to the bridge. Pressure field bridge deflection monitoring method is one of the most widely used means of monitoring, it has a extensive application in the static deflection monitoring, however, the research on dynamic deflection monitoring is relatively few. This paper based on the fluid dynamics theory, analysis the fluid pipe tube flow caused by structural vibration, and its effect on the measurement point pressure of connected pipe, and analysis the effect from bubble, pipeline step arrangemen. Design pressure pipe bridge deflection monitoring system model, through model test, get deflection time history data base, analysis the test data and research dynamic deflection monitoring accuracy.The main work and results of this paper are as follows:(1) This paper describes the current methods of deflection monitoring, and introduces the research status of the pressure field deflection monitoring method, and its application in dynamic deflection measurement;(2) Describe the theory of fluid dynamics in detail, and analyze the dynamic characteristics of fluid in the pipe with the principle of AC hydraulic system; According to the theory of fluid dynamics, combined with the principle of AC hydraulic system, analysis of the dynamic characteristics of the fluid in the pipe, and the effect of stepped pipeline on the distribution of pressure field;(3) Based on the control factors of vibration frequency and longitudinal direction, ueing the material mechanics, structural dynamics analysis and MIDAS-civil modeling analysis, construct experimental model. Using the Rossmonte 3051 cd the differential pressure transmitter, ADAM-4117 acquisition card, RS-485, DASP data analyzer, SDA-830 C displacement data acquisition formed two groups deflection acquisition equipment;(4) Based on the condition of conventional instrument and equipment, collect and analyze the deflection value of the displacement excitation;(5)Based on the connection pipe with different amount of bubbles to collect the deflection, analysis of deflection measurement error,research its effect on deflection measurement acquisition;(6) Construct step tube type connecting pipe, based on the test conditions of different excitation value, step height and longitudinal distance to collect deflection,and analyze the influence on deflection measurement from above factors. Provide the basis for the reasonable arrangement of the measuring points in the vicinity of the step pipeline.