Investigation Into Aerostatic Action Of Long-span Bridge Based On Field Measurement

To bridge structure, wind loads is one of the most important loads among bridgestructure design. It is occurred frequently that bridges are destroyed by wind force.With the span largening, bridge structure is becoming more and more sensitive towind force. Besides, wind-resistant behavior of bridge structure with the influencesof wind loads is turning into a controlling element during bridge design andconstruction. Therefore, studying the distribution of wind pressure under theinfluence of wind loads is rather important to wind-resistant design research.Currently, research methods on wind-resistant design consists of wind tunnel test,simulation and field observation. Among them, field observation is considered as themost reliabel one, for gathered test data are more accurate and coincident with thedynamic characteristics of real structure. However, because of the influences ofincontrollable weather and other objective factors, researches on wind-resistantbehavior of bridge structure by field observation are fairly rare both at home andabroad. This thesis chooses Dongting Lake Bridge, located in Yueyang, HunanProvince, as the support construction. Based on the field measurement to researchthe characteristics of wind field and wind pressure of the girder section in main spanand the overhead in main tower, and this thesis provides an reference forwind-resistant design studies of long-span bridge structure. This thesis contains thefollowing three main works:1. By referring basic theories of the fluid transmission pipeline dynamics toanalyse the frequency-response of pressure transmission pipeline. Designed the rightwind pressure measurement system and verified its accuracy to assured theauthenticity of data through testing.2. Choose suitable location of the grider section and tower top to arrangedmeasurement points according to the experiment pupose, and laying pressuretransmission pipe and instrument testing.This thesis also operates at least twosuccessful wind field and wind pressure observation experiments.3. Through processing study data using Matlab numerical analysis software,this thesis obtains and analyses the characteristics parameters of wind field in mainbeam section and overhead, distribution characteristics of wind-pressure, correlationbetween wind field and wind pressure and the relativeness between aerostaticcoefficients of Tri-component and wind field.