由于结构存在阻尼现象,弹性波在传播过程中信号强度必然会随传播距离而衰减。据此提出弹性波极限传播距离与传感器极限布置间距概念,考虑到在高频率处剪切变形引起的转动惯量对结构动力特性的影响比较大,基于Timoshenko梁理论,结合经典回传射线矩阵法,提出使用局部散射矩阵确定结构损伤检测中的传感器布置极限间距,并将其应用到传感器优化算法中。针对指定检测系统,以桥梁结构Benchmark模型为例,验证算法的有效性。
Taking into account the influence of inertia due to the shear deformation at high frequencies on the dynamic properties of structure,based on Timoshenko beam equation,combined with classic reverberation matrix method,a new method is proposed to determine the utmost distance of sensor arrangement using the revised local scattering matrix in structural damage detection.First,calculate the utmost distance of wave propagation on a special structure by the principle of elastic wave propagation and determine the preliminary number of sensors;second,the utmost distance and number of sensors are applied to a sensor optimization algorithm named effective independence driving-point residue method.In the bridge Benchmark model case study,it shows the validity of proposed method under special detection system.