Study On Lateral Bearing Capacity And Lateral Stiffness Of Prestressed Brick Walls

Due to the low shear strength, low tensile strength and low bend strength of brick wall, it is difficult to apply masonry to high-rise structures in high degree seismic fortification intensity. On the other hand, because of the low shrink and creep of masonry, prestressed masonry could be used widely. In this paper, based on the tests of prestressed brick masonry walls processed by professor Luo Wankang of Chongqing University, advanced researches on seismic behavior of prestressed brick masonry walls are made, and simplified semi-empirical formulas of the ultimate lateral bearing capacity and stiffness for engineering design are put forward. These formulas are the basic condition to apply the prestressed brick wall system to high-rise structures, and help people get a deeper understanding of the seismic behavior of prestressed brick masonry walls.The main works of this paper are formed of four major parts as follows:1. Based on the tests of prestressed and nonprestressed brick masonry walls and house models with peripheral beams and constructions columns under cyclic lateral loading, advanced researches on the ultimate lateral bearing capacity, ductility, deformation and energy dissipation are made. The results show that prestressed brick masonry walls have better seismic behavior and prestressed brick masonry wall system is a good seismic system.2. Some kinds of calculation methods of the ultimate lateral bearing capacity of nonprestressed brick walls with peripheral beams and constructions columns are discussed. In order to reflect the influence of the prestressing force, necessary modifications are made, and a simplified semi-empirical formula of the ultimate bearing capacity for engineering design is put forward. The calculating results accord with the tests results well. 3. Based on calculation methods of the inter-storey lateral stiffness, simplified semi-empirical formulas of the inter-storey lateral elastic stiffness, cracking scant stiffness and post-cracking stiffness of prestressed brick walls are put forward.4. A five storey prestressed brick wall structure in 9 degree seismic fortification intensity is designed. This structure exceeds the limits of "code for seismic design of buildings", but the calculating results show that the bearing capacity of its brick walls can meet the requirement of 9 degree seismic fortification intensity and prove that it ispossible to apply prestressing techniques to the seismic brick walls in high seismic fortification intensity.