A single-room,single-storey full-scale brick masonry building with precast RC roofing system was tested thrice under displacement controlled lateral cyclic loading,to assess the effectiveness of the basic repair and s...A single-room,single-storey full-scale brick masonry building with precast RC roofing system was tested thrice under displacement controlled lateral cyclic loading,to assess the effectiveness of the basic repair and seismic strengthening techniques.Initially,the virgin building specimen was loaded laterally to f^tilure.In the second stage,the damaged building was repaired by stitching across the cracks,and tested under the same lateral loading.In the third stage,the twice-damaged structure was repaired once more by stitching and strengthened by twin lintel belt in steel and vertical comer reinforcement, and re-tested.The building strengthened by twin lintel belt in steel showed about 28% higher strength under lateral loading than the virgin building.展开更多
The Himalayan region is one of the major seismic areas in the world.However,similar to many other seismically active locations,there are substantial numbers of unreinforced masonry(URM)buildings;the majority of which ...The Himalayan region is one of the major seismic areas in the world.However,similar to many other seismically active locations,there are substantial numbers of unreinforced masonry(URM)buildings;the majority of which have not been designed for seismic loads.Past seismic events have shown that such buildings are highly vulnerable to earthquakes.Retrofitting of these URM buildings is an important concern in earthquake mitigation programs.Most government school buildings in rural areas of northern India are constructed of unreinforced masonry.These school buildings are socially important structures and serve as a crucial resource for rehabilitation during any disaster.The effectiveness of ferrocement(FC)to create a URM-FC composite is described in this study by estimating the performance and fragility of a URM school building before and after a retrofit.Analytical models,based on the equivalent frame method,are developed and used for nonlinear static analysis to estimate the enhancement in capacity.The capacity enhancement due to retrofitting is presented in terms of the maximum PGA sustained and damage probabilities at the expected level of earthquake hazard.展开更多
On May 5, 2008, China experienced a devastating earthquake, also known as Wenchuan earth-quake. Many buildings, whose seismic design levels were too low to endure a strong earthquake, were severely damaged or even des...On May 5, 2008, China experienced a devastating earthquake, also known as Wenchuan earth-quake. Many buildings, whose seismic design levels were too low to endure a strong earthquake, were severely damaged or even destroyed in the disaster.展开更多
Jazan area is located in the most active seismic zone region of the Kingdom of Saudi Arabia where there is a complicated geological structures and tectonics. This project reviews the seismic activities occurred in Jaz...Jazan area is located in the most active seismic zone region of the Kingdom of Saudi Arabia where there is a complicated geological structures and tectonics. This project reviews the seismic activities occurred in Jazan area together with reviewing the Saudi Building (Seismic) Code (SBC-301-2007) [1]. A multi-story reinforced concrete building, in Jazan city, was seismically analyzed using the Equivalent Lateral Force Procedure with the aid of STAAD PRO software. The building, which was Ordinary Reinforced Concrete Moment Resisting Frame (ORCMRF), was analyzed in compliance with the provisions of (SBC-301-2007) [1]. The most important parameters governing the analysis of this frame were dead load, live load and seismic loads. Seismic loads were computed as pairs of accelerations versus times. The damping ratio was taken as 0.05 (5% of the critical damping). The ground accelerations versus time periods were calculated using SBC-301-2007 together with parameters necessary to be used as input data for the program to calculate the seismic parameters, i.e., reactions, displacements, base shear, bending moments, shearing forces, drifts. The obtained results show effects of earthquake ground motions on building studied herein are so greater for the higher increases of the values of outputs resulting from seismic loads comparing to that due to static load only. Finally, the results obtained, clearly, show the importance of taking the Saudi seismic code provisions into account when analyzing and designing multi-story buildings in Jazan area.展开更多
Several reinforcing schemes are illustrated that are based on the loading characteristics of typical country masonry school buildings with sparsely spaced transversal walls and large depth. From the seismic damage obs...Several reinforcing schemes are illustrated that are based on the loading characteristics of typical country masonry school buildings with sparsely spaced transversal walls and large depth. From the seismic damage observed following the Wenchuan Earthquake, the effects of reinforcing schemes, tie-columns and tie-beams on the seismic resistance of masonry buildings are analyzed. The concept of improving the ductility of these types of buildings is presented. Finally, some suggestions are proposed for the design of masonry buildings with sparsely spaced transversal walls and large depth.展开更多
文摘A single-room,single-storey full-scale brick masonry building with precast RC roofing system was tested thrice under displacement controlled lateral cyclic loading,to assess the effectiveness of the basic repair and seismic strengthening techniques.Initially,the virgin building specimen was loaded laterally to f^tilure.In the second stage,the damaged building was repaired by stitching across the cracks,and tested under the same lateral loading.In the third stage,the twice-damaged structure was repaired once more by stitching and strengthened by twin lintel belt in steel and vertical comer reinforcement, and re-tested.The building strengthened by twin lintel belt in steel showed about 28% higher strength under lateral loading than the virgin building.
文摘The Himalayan region is one of the major seismic areas in the world.However,similar to many other seismically active locations,there are substantial numbers of unreinforced masonry(URM)buildings;the majority of which have not been designed for seismic loads.Past seismic events have shown that such buildings are highly vulnerable to earthquakes.Retrofitting of these URM buildings is an important concern in earthquake mitigation programs.Most government school buildings in rural areas of northern India are constructed of unreinforced masonry.These school buildings are socially important structures and serve as a crucial resource for rehabilitation during any disaster.The effectiveness of ferrocement(FC)to create a URM-FC composite is described in this study by estimating the performance and fragility of a URM school building before and after a retrofit.Analytical models,based on the equivalent frame method,are developed and used for nonlinear static analysis to estimate the enhancement in capacity.The capacity enhancement due to retrofitting is presented in terms of the maximum PGA sustained and damage probabilities at the expected level of earthquake hazard.
文摘On May 5, 2008, China experienced a devastating earthquake, also known as Wenchuan earth-quake. Many buildings, whose seismic design levels were too low to endure a strong earthquake, were severely damaged or even destroyed in the disaster.
文摘Jazan area is located in the most active seismic zone region of the Kingdom of Saudi Arabia where there is a complicated geological structures and tectonics. This project reviews the seismic activities occurred in Jazan area together with reviewing the Saudi Building (Seismic) Code (SBC-301-2007) [1]. A multi-story reinforced concrete building, in Jazan city, was seismically analyzed using the Equivalent Lateral Force Procedure with the aid of STAAD PRO software. The building, which was Ordinary Reinforced Concrete Moment Resisting Frame (ORCMRF), was analyzed in compliance with the provisions of (SBC-301-2007) [1]. The most important parameters governing the analysis of this frame were dead load, live load and seismic loads. Seismic loads were computed as pairs of accelerations versus times. The damping ratio was taken as 0.05 (5% of the critical damping). The ground accelerations versus time periods were calculated using SBC-301-2007 together with parameters necessary to be used as input data for the program to calculate the seismic parameters, i.e., reactions, displacements, base shear, bending moments, shearing forces, drifts. The obtained results show effects of earthquake ground motions on building studied herein are so greater for the higher increases of the values of outputs resulting from seismic loads comparing to that due to static load only. Finally, the results obtained, clearly, show the importance of taking the Saudi seismic code provisions into account when analyzing and designing multi-story buildings in Jazan area.
文摘Several reinforcing schemes are illustrated that are based on the loading characteristics of typical country masonry school buildings with sparsely spaced transversal walls and large depth. From the seismic damage observed following the Wenchuan Earthquake, the effects of reinforcing schemes, tie-columns and tie-beams on the seismic resistance of masonry buildings are analyzed. The concept of improving the ductility of these types of buildings is presented. Finally, some suggestions are proposed for the design of masonry buildings with sparsely spaced transversal walls and large depth.
