Research On Bridge Damage Based On The Curvature Variation Of The Deck

For the lack of quantifying science bases in bridge health detection,Prof.Zhou zhixiang puts up the “Bridge Physiognomy Theory”,which provides a totally new valuating method to judge bridge structural health by the change of deck form.This paper relies on the text of Chongqing Natural Science Foundation of China:Bridge Safety Assessment Methods and Face Perception Theory(project number:cstc2012jjB0118).The corresponding relationship of deck form and structural damage has been studied by theoretical analysis and experimental study.The main contents and conclusions of this paper are as follows:1?In an example of a simply supported T-beam bridge,the author carried out load test twice,respectively on damaged bridge and undamaged condition.In each working conditions,Leica Ms50 was used to obtain the point cloud of 3D geometric coordinate of deck.The noise was deleted effectively from point cloud data by Geomagic Studio.After the point cloud data being 3D compared by Geomagic Qualify,the very small deflection can be clearly observed from deflection curve in each working conditions.2?According to the mutation of deflection curve in structural damage,“Damage Identification Method Based on mutations of surface curvature ” was put forward.Depending on structural form of the point cloud data,the author chose a method for estimating Gauss curvature.3?The model of PMMA Simple T-beam bridge was established by ABAQUS.Under the action of dead load,the model respectively simulated deck forms on the condition of different degrees?location and numbers of cracks in mid-span at boundary beam.And the Gauss curvature of deck was estimated in each working conditions.The analysis indicates it can effective identify the degree?location and numbers of injury.Finally,this method was applied to the point cloud data of PMMA deck to distinguish the damage of bridge structure.The location of damage distinguished coincided with the actual location.