山西稷王山砖塔地震动力响应及损伤分析

采用数值分析方法对山西稷王山古塔在不同地震作用下的破坏形态及损伤进行计算分析,为古塔的抗震加固提供依据,采用塑性损伤本构计算模型描述地震作用下砌体结构的损伤失效,给出古塔在不同调幅系数地震波作用下的位移形态,获得层间位移、加速度放大系数等地震响应数值,讨论了地震引起的损伤分布规律。结果表明,稷王山古塔整体刚度分布均匀,塔顶加速度放大系数最大,尽管古塔底部墙体厚于上部,但在地震作用下仍在底层首先出现受拉损伤,并随地震强度提高而向上扩展;应力云图显示,地震作用下古塔底层最大主拉应力区呈斜向上扩展形态,易使塔体形成斜向裂缝;古塔薄弱层为底部3层及顶层。

Seismic response and damage analysis of the pagoda on Shanxi Jiwang Mountain

In this paper, the failure mode and damage of pagoda on Shanxi Jiwang Mountain under different earthquakes were calculated and analyzed by numerical method, which provides a basis for the seismic reinforcement of Jiwang pagoda. The plastic damage constitutive model was applied to describe the damage failure of masonry structures under earthquake. The displacement forms of the ancient pagoda under the action of seismic waves with different amplitude-modulation coefficients were given,the seismic responses values such as interlayer displacement and acceleration amplification factors were obtained, and the distribution rules of earthquake-induced damage were discussed. The results show that the overall stiffness distribution of the pagoda on Jiwang Mountain is uniform, and the acceleration amplification factor at the top pagoda is the greatest. Although the bottom wall of the pagoda is thicker than that on top, the tensile damage still initiated from the bottom under earthquake, and it expands upward with increase of seismic intensity. The stress contours show that the maximum principal tensile stress area at the bottom of the pagoda under earthquake expands obliquely, which easily leads to the formation of oblique cracks in the pagoda. The weak layers of the pagoda are the bottom three layers and the top layer.