钢筋混凝土包护结构应力波传播特性研究

Effect of missing grout on the propagation of stress wave in reinforced concrete structure

采用数值计算法，研究了应力波在钢筋混凝土包护结构中传播特性。针对两种注浆特性的混凝土钢筋包护结构：混凝土注浆脱空50％和混凝土注浆完全脱空，建立了两组对应的钢筋混凝土包护结构数值模型。通过ANSYS／LS—DYNA有限元软件计算得到应力波在两组模型中传播的时域信号，根据所得的时域信号分析得出应力波在两类模型中传播的固结波速和平均振幅比。结果表明：在注浆脱空50％情况下固结波速处于3200-4300m／s范围内，并随着注浆脱空尺寸的增加而增大，平均振幅比处于0．15～0．85范围内，并随着注浆脱空尺寸的增加而减小；在注浆完全脱空情况下固结波速处于3400-4400m/s范围内，并随着注浆脱空尺寸的增加而增大，平均振幅比处于O．1～0．75范围内，并随着注浆脱空尺寸的增加而减小。

Studied the effect of propagation characteristic on stress wave in reinforced concrete structure by using numerical simulation method.The concrete structure can be classified into two categories with respect to the missing grout：reinforced concrete structure with missing grout 50% and reinforced concrete structure with complete missing grout, in light of these missing grout, numerical model for rein- forced concrete structure was built.The time domain signal of stress wave propagation in the two modes were calculated by fem software ANSYS/LS-DYNA, according to the results of time domain signal, we can get the consolidating wave speed and average amplitude ratio at which stress wave propagates in the two models.The results demonstrate that the consolidating wave speed in the range of 3 200 m/s to 4 300 m/s in case of missing grout 50%, and increases with the increase missing grout size, in addition, average amplitude ratio at 0.15 to 0.85 and increases with the increases of size of missing grout;the consolidating wave speed in the range of 3 400 m/s to 4 400 rrds in case of complete missing grout, and increases with the increase missing grout size, in addition, average amplitude ratio at 0.1 to 0.75 and increases with the increases of size of missing grout.