Proposed Seismic Design Method for Story-Adding-Structures of Existing Brick Masonry Building Using Unitary Masonry-In-Frame System

摘要

A Practical method of seismic design is proposed for story-adding structures of brick masonry buildings. It is recommended that the respective lateral elastic stiffness of the frame and brick masonry walls be adopted to calculate the natural period of vibration of the structure, overall earthquake loading, and shear force at each floor, and the earthquake shear forces should be distributed between the frame and masonry walls according to the proportion of their respective elastic stiffness to check the seismic strengthening effect for the existing brick masonry structure. Similarly, the shear forces at each story apportioned by the ratio of the reduced stiffness of the masonry wall to the elastic stiffness of the frame are used as a seismic design basis of the frame structure. Detailed procedures are also included to assist designers in the seismic design.