The Study On Seismic Behavior And Reinforcement Key Problem Of Low-intensity Rowlock Cavity Wall

The brick masonry structure is a traditional structure in China, it has very long history, and rowlock cavity wall is one of its forms, which has been largely used for the construction of Residential houses since the Ming Dynasty. At present, there are a lot of rowlock cavity wall houses in most towns and villages of our country, but we know little about the seismic performance of the rowlock cavity wall, and many investigations of earthquake damage show that studying the seismic performance of such walls is of great significance to rural residential construction on the earthquake disaster prevention of our country.This paper is based on the subject of "Applied Technology of Rural Residential Construction on the Earthquake Disaster Prevention of Hunan Province and Related Policy Research", and it focuses on reserching seismic behavior of the low-intensity rowlock cavity wall. Based on the experimental study of 6 rowlock cavity walls and 1 solid common wall subjected to horizontal low cyclic loading, this paper analyzed the three modes of brickworks of rowlock cavity wall, under two kinds of vertical stress. The study consists of failure process and patterns of walls and basic seismic behavior indexes such as the capability of seismic shear, the hysteresis curves, skeleton curves, the stiffness and stiffness variation, the ductility and deformability. Results from experiments showed that the seismic behavior of rowlock cavity wall is very poor, since its seismic shear strength is low, its stiffness degenerates quickly, its energy dissipation ability is weak and it has very brittle fracture characteristics. Furthermore, on the basis of experimental results to check and compare to the existing masonry structure seismic shear strength theories and formulas, the capability of seismic shear formula of the low-intensity rowlock cavity walls was presented. It can be used for calculating the capability of seismic shear of such wall in practice projects.The research results can be used as the theoretical basis on seismic strengthening of rowlock cavity wall.Since the seismic behavior of the low-intensity rowlock cavity wall is poor, this subject also researched on seismic behavior of the High-Performance Ferrocement Laminate (HPFL) to strengthen rowlock cavity wall, we found that shear dowel in HPFL play a crucial role on the reinforcement effect. Therefore, focusing on behavior of shear dowel in Ferrocement Laminate Thin, we have done a great deal of inorganic embedded-bar experiments. By means of pull-out tests of the inorganic embedded-bar in brick masonry and concrete, we further verified the bond performance of inorganic embedded-bar adhesive, and observed the effects of bond performance by steel type, diameter and depth of embedded steel bars in particular. Then, through the finite element analysis on the embedded steel bars in concrete structures, it further confirmed the above conclusion, and obtained the depths and spacing of embedded-bar formula, which provided the basis for the High-Performance Ferrocement Laminate(HPFL)to strengthen the brick masonry structure.