الفهرس | Only 14 pages are availabe for public view |
Abstract Since the dawn of human civilization, masonry has been used to construct all types of buildings, bridges, roadways and other engineering works. Confined masonry (CM) is considered one of the popular forms of low-cost, low-rise construction throughout the world. Confined masonry consists of no reinforced masonry walls surrounded by concrete tie-columns, in the vertical direction, and tie-beams, in the horizontal direction. In some countries confined masonry walls may include joint reinforcement.The behavior of constrained masonry structures under cyclic lateral loads was investigated in an experimental research. This text presents the results of lateral cyclic loading tests conducted on two-story confined masonry building using local materials and standards in consideration. Three confined masonry buildings with a two-story building half-scale were built, consisting of a clay masonry panel, confining columns,tie beams, and R.C.slabs. The assemblies were tested under its vertical self-weight and lateral reversed cyclic loading with a displacement controlled loading protocol up to failure. The assembly walls have different perforations (solid / windows / doors) to investigate perforation effect on the in-plane and out-of-plan performance. With increasing displacement, lateral cyclic loads were applied to the model. Crack pattern,failure mechanism, lateral capacity, energy dissipation, ductility, and overall structural performance were all evaluated. Out of plane walls provided additional restrictions for wall movements and increased structural performance, while masonry infill walls provided significant strength and ductility. The findings show that confined masonry structures constructed to the standard will withstand the design lateral loads successfully. As part of a research effort aimed at producing a structurally and economically effective hybrid construction system for developing countries in general, and Egypt specifically. The lateral load behavior of retrofitted confined masonry walls utilizing a low cast ferrocement system planned and manufactured using locally accessible materials and standard craftsmanship and construction procedures is the subject of this research. In addition to a Retrofitted assembly using external layer of ferrocement. Key experimental results showed that the proposed upgrading technique improved the lateral resistance of the confined assembly by about (61% - 95%) and increasing ductility and total energy absorbed by 27%. The max. Lateral drift at failure was reduced by about (23% - 31%) however the corresponding load for first visible crack was increased by (150% -175%). |