晋祠舍利生生塔砖结构的地震破坏形态研究

摘要

鉴于我国古塔砖结构在强震中呈现的墙体弯曲型破坏形态及优异的抗震性能,本文对太原晋祠舍利生生塔结构的地震破坏形态进行了分析.首先将塔身作为整截面墙体分析了其地震内力及受弯、受剪承载力,定义并计算了受弯、受剪负载系数,对各层的破坏形态进行了分析,研究得出塔体底部墙体为弯曲破坏形态、上部为剪切破坏;进一步,建立结构的有限元模型并施加等效水平地震侧力,通过定义和计算单元的拉压负载系数,研究了墙体弯曲破坏时受拉、受压区的失效过程,结果表明,塔体下部墙体弯曲破坏时,截面受拉区先拉裂失效,继而受压区失效破坏.本研究为砖塔的维修加固提供了依据,特别对古塔砖结构的地震破坏形态作了探索,旨在为当代砌体结构寻找高效抗震减灾途径.%Whereas the ancient brick pagoda embodies bending failure features in walls and shows excellent seismic performance,failure configuration of the Shelishengsheng Pagoda in the Jinci Temple subjected to earthquakes is investigated. Firstly, configuration of earthquake failure is studied by defining shear & bending load factors based on analyses of seismic internal force of the pagoda sections together with their shear and bending capacity. It is concluded that the bottom brick wall of the pagoda will show bending failure and the upper wall will show shear failure. Secondly, finite element model is established and equivalent horizontal seismic force is imposed on the model. Failure courses in the tensile and compressive region of the bending failure section are explored by means of defining and calculating tensile & compressive load factors of elements. The results show that the cracking in the tensile region is prior to crushing in the compressive region of nether wall section of the pagoda with bending failure features. The research supplies maintenance and retrofit of the pagoda with groundwork. Besides, the paper explores earthquake failure configuration of ancient brick structures so as to search approaches and guides to effective earthquake resistance for up-to-date masonry structures.