传统穿斗木结构榫卯节点附加黏弹性阻尼器振动台试验

通过对一个两层、足尺、长宽高为3.8m×3.6m×3.9m的穿斗式木结构房屋模型的榫卯节点附加黏弹性阻尼器进行振动台试验,研究了结构的抗震性能,并对0.07g、0.4g两种峰值加速度下进行了榫卯节点附加阻尼器和未附加阻尼器的进行了振动台对比试验。试验结果表明：榫卯节点附加了黏弹性阻尼器后节点刚度增大,减小了半刚性榫卯节点的转动能力,并使结构在地震激励作用下的变形恢复能力得到了大幅提高,经过多次重复地震,即使经历0.95g的地震激励后,结构模型也未发生明显倾斜破坏;结构一层柱顶榫卯节点最先发挥减震耗能作用,动力放大系数随着地震激励增加呈减小趋势,由于结构两个方向刚度及质量分布的不均匀,X、Y方向动力放大系数有差异,X方向动力放大系数在1.2519~0.7775之间,Y向1.8779~1.1152之间。榫卯节点附加黏性阻尼器达到了小震下减小层间位移角,大震下增强榫卯节点变形恢复能力的目的。

Shaking table tests of mortise-tenon joints of a traditional Chuan-Dou wood structure attached with viscoelastic dampers

Shaking table tests were carried out for a 3.8m×3.6m×3.9m (length×width×height) full-scale two-storey Chinese traditional wood structure attached with viscoelastic dampers. To study the seismic performance of Chinese traditional wood structure with and without viscoelastic dampers, they were tested under the peak ground acceleration (PGA) of 0.07g and 0.4g, respectively. The experimental results show that after attaching the viscoelastic dampers, the stiffness of mortise-tenon joints can be greatly increased so that rotation capability of the semi-rigid joints can be decreased, and the deformation restoring capacity of the structure model can be greatly enhanced. After experiencing multiple repeated earthquakes, there was no obvious tilt damages in the structure model even for 0.95g PGA. Shock absorption of mortise-tenon joints at the top of columns of the first floor firstly came into play. The dynamic amplification factor may decrease with the increase of the input seismic excitation. Due to the non-uniform distribution of mass and stiffness in two directions of structure model, the dynamic amplification factors in X and Y directions of the structure model were different, since the dynamic amplification factors in X and Y directions may vary in the range of 1.2519~0.7775 and 1.8779~1.1152, respectively. Mortise-tenon joints of structure model with attached viscoelastic dampers, the purposes of decreasing the story drift in small earthquakes and enhancing the deformation restoring capability of joints in strong earthquakes can be realized.