关于土层地震反应分析中阻尼矩阵建模方式的讨论

阻尼矩阵的选择对土层时域内地震反应计算的准确性有重要意义。本文构造了质量比例阻尼、刚度比例阻尼、Rayleigh阻尼、Caughey阻尼和Clough阻尼矩阵，研究各阻尼对土层地震反应分析精度的影响。以苏通大桥5号桥塔基础处的工程场地为例，分别以人工合成基岩波，Northridge波、Parkfield波和汶川波为输入，得到不同阻尼模型下土层的地震反应，结果表明Clough阻尼在计算精度和误差稳定性上要优于其他阻尼模型，针对Clough阻尼的不足之处提出了改进方法，算例表明改进后的Clough阻尼能在保证计算精度的前提下减少计算机的存储量和计算量。

Discussion on modeling method of damping matrix in seismic response analysis of soil layer

Damping matrix is very important to accuracy of seismic ground response analysis in time domain.The damping matrices corresponding to mass-proportional damping, stiffness-proportional damping, Rayleigh damping, Caughey damping and Clough damping were constructed to study their influence on the accuracy of the seismic response analysis of the soil layer.Taking soil layerat No.5 tower of Sutong bridge as an example,the seismic responses of the soil layer with different damping models were computed by using artificial bedrock waves, Northridge waves, Parkfield waves and Wenchuan waves as inputs. The results show that Clough damping can reduce error of seismic response analysis and improve error stability, and is superior to other damping models in computational accuracy and error stability.An improved method was proposed for the deficiency of Clough damping. The improved Clough damping can reduce the storage and computational quantity of the computer on the premise of ensuring the computational accuracy.