Displacement reconstruction of beam structures from temporal or spatial second derivatives of displacement
This study presents two displacement reconstruction schemes using second derivatives of displacement,which are acceleration and strain.Both schemes are defined by inverse analyses based on the equation error estimation(EEE)minimizing the equation error of the second order differential equations.Since each inverse analysis has its own difficulties to be solved,additional information or treatments are required.The displacement reconstruction from acceleration is defined by a regularized EEE.The regularization term making the dynamic displacement to stay around the static displacement is added to the EEE.The regularization term includes a regularization factor that adjusts the regularization effect.The regularization factor is defined by the target frequency,the lowest meaningful frequency,and the target accuracy,the desired accuracy of the reconstructed displacement at the target frequency.The standard finite element(FE)procedure is applied for discretization,and the overwrapping moving time window is introduced to treat unknown boundary conditions.The suggested method becomes a symmetry finite impulse response filter that does not have phase error.The displacement reconstruction using measured strain is defined by supports conditions as well as the EEE minimizing the equation error of the strain-displacement relation.The standard FE procedure is employed to numerically solve the inverse analysis of the strain-displacement relation.The validity of displacement reconstructions is tested through a field test and a numerical example.A bridge for trains under commercial operation is utilized to show the validity of the displacement reconstruction from measured acceleration.The validity of the displacement reconstruction from measured strain is shown by a numerical example of a simply supported beam.Both examples show that the displacements are successfully reconstructed by suggested schemes even the measurements are polluted by noise.
Displacement reconstruction Measured acceleration Measured strain Second derivative Equation error estimation
Kwang-yeun Park Hae Sung Lee
Senior Researcher,Institute of Construction and Environmental Engineering,Seoul Natl Univ.,Seoul,Ko Professor,Dept.of Civil and Environmental Engineering,Seoul Natl Univ.,Seoul,Korea
国际会议
The 7th World Conference on Structural Control and Monitoring(7WCSCM)(第七届结构控制与监测世界大会)
青岛
英文
2130-2139
2018-07-22（万方平台首次上网日期，不代表论文的发表时间）