界面剥离钢-混凝土组合结构应力波传播谱元法模拟研究

建立钢-混凝土组合结构截面二维谱元法模型，针对钢-混凝土界面完好以及存在界面剥离时模型在单点激励下弹性应力波场进行模拟分析，探究弹性应力波的传播规律。采用去除混凝土单元的方法反映组合结构中钢板与混凝土之间的界面剥离。通过对比分析表明界面剥离的存在对弹性应力波场以及模型上不同位置的位移响应产生影响。通过改变界面剥离程度，得到测点位移的变化规律。通过模拟，谱元法可以有效模拟钢-混凝土组合结构中弹性波的传播规律，为研究基于应力波测量的钢-混凝土组合结构界面缺陷检测机理提供帮助。

NUMERICAL SIMULATION ON STRESS WAVE PROPAGATION OF STEEL-CONCRETE COMPOSITE STRUCTURES WITH INTERFACE DEBONDING BY SPECTRAL ELEMENT METHOD

To investigate the elastic stress wave propagation in steel-concrete composite structures, a 2 dimensional spectral element model for steel-concrete composite sections was established and the elastic stress wave propagation in the hybrid section with and without interface debonding defects was simulated under single point excitation. The interface debonding was simulated by removing concrete elements between steel tube and concrete core. The wave field and displacement responses of different nodes between the models with and without defects were compared to explain the effect of interface debonding on elastic stress wave propagation. Finally, the displacement responses of different numerical models with different levels of interface debonding were compared to investigate the relationship between the displacement response and the interface debonding defects. Spectral element method (SEM) provides an efficient way for the stress wave simulation of steel-concrete composite structures, which is helpful for the study on the mechanism for interface debonding detection of steel-concrete composite structures based on stress wave measurement.