古建筑加固前、后动力性能研究

DYNAMIC BEHAVIOR RESEARCH OF UNREINFORCED AND REINFORCED ANCIENT ARCHITECTURES

采用等效体积单元法对采用喷射混凝土方法加固的砌体结构古建筑在加固前、后抵抗地铁开挖过程中产生的爆破振动荷载的动力性能进行分析。通过分别建立加固前、后结构的模型并进行时程分析,对比结构周期、底部总剪力、顶点侧向位移和墙体的应力,得出采用喷射混凝土的加固方法,提高了结构的刚度和整体性,混凝土部分承担了爆破荷载作用下的大部分剪力,避免了古建筑被损坏。

The blasting vibration effect in the subway excavation process of a multistory masonry building strengthened by shotcrete was analyzed using representative volume element model. Finite element models for both the original structure and the strengthened one were established, and time-history analysis was performed. The effect of shotcrete strengthening on masonry walls was analysed from the structural period, structural stiffness, top lateral displacement and stress level. The result shows that the structural stiffness is effectively enhanced and integrity of the structure is improved. Since the major portion of shear force of the blasting vibration effect in the strengthened wall is resisted by the strengthening concrete layer, the stresses in the masonry wall are reduced and the structural failure is avoided.