A Method And Research For Bridge Deflection Measurement Base On Rotating Angle Of Beam

Bridge construction is vital to people's life and property safety, social stability and sustainable development of economy. Therefore, the periodic detection of the bridge is an important measure to ensure its safe operation. Bridge deflection is not only an important part for bridge inspection, but also a vital index to evaluate bridge safety. This paper puts forward a new method for measuring bridge deflection based on the beam rotation angle and a new measuring device of beam rotation angle. It also carries out theoretical analysis and experiments according to the measuring method and device.The thesis mainly includes the following three parts:Firstly, it summarizes the current situation and latest progress of the study of bridge deflection at home and broad and analyzes the deflection measurement's advantages, disadvantages and applicable scope. On that basis, the author puts forward a new measuring method and device based on beam rotation angle for measuring bridge deflection.Secondly, based on the theoretical analysis of the beam rotation angle for measuring bridge deflection, the author introduces a calculating method of measuring bridges'deflection curves based on beam rotation angle--cubic spline function method.Thirdly, the author researched and developed a set of measuring device based on the beam rotation angle. The author did many precisely comparative experiments on the model of simply supported girder bridge in the laboratory and theoretically analyzed and processed the measuring result.The experimental result shows that the device based on beam rotation angle for measuring bridge deflection has the advantages of high measuring efficiency, less environmental restriction, application to most bridge types, good cost performance, etc. It is hoped to meet the requirements of bridge deflection measurement in practical engineering.