In design and construction of low/high rise buildings, different forms of construction can be applied such as concrete shear wall structural system and framed structural system without or with masonry infill walls. At...In design and construction of low/high rise buildings, different forms of construction can be applied such as concrete shear wall structural system and framed structural system without or with masonry infill walls. At present, most buildings in East Africa are constructed as reinforced concrete framed structures with strong masonry infill, but during design, engineers assume that the masonry infill panels have zero contribution in offering load resistance. Due to the problem above, a study with an objective of finding out the influence of masonry panels on the properties of reinforced concrete infilled frame under vertical load has been done. Three types of models: reinforced concrete frame model, masonry model and reinforced concrete frame with masonry infill, were investigated using finite element technique. In additional to the finite element analysis, laboratory models were prepared and tested so as to check the validity of the analytical results. The obtained results have led to an establishment of a mathematical model which may be useful to the design engineers since masonry wall panels can now be considered as load bearing elements. Such consideration of frame together with masonry leads to an accurate and optimal design of the frame, resulting into lesser amount of reinforcement and geometrical properties of the frame.展开更多
The research presented in this paper deals with the seismic protection of existing frame structures by means of passive energy dissipation. An iterative displacement-based procedure, based on capacity spectrum, to des...The research presented in this paper deals with the seismic protection of existing frame structures by means of passive energy dissipation. An iterative displacement-based procedure, based on capacity spectrum, to design dissipative bracings for seismic retrofitting of the frame structures is described, and some applications are discussed. The procedure can be used with any typology of dissipative device and for different performance targets. In this work, the procedure has been applied, with both traditional pushover (load profile proportional to first mode) and multimodal pushover, to an existing RC (reinforced concrete) frame building. In the application, the buckling restrained braces have been used in order to prevent damages to both the structure and non structural elements. The use of multimodal pushover proves to be more effective than pushover based on single mode in case of medium rise RC frame building (higher than 30 m) but, once this building is retrofitted, and therefore regularized, with a bracing system, the difference between using monomodal or multimodal pushover becomes insignificant.展开更多
文摘In design and construction of low/high rise buildings, different forms of construction can be applied such as concrete shear wall structural system and framed structural system without or with masonry infill walls. At present, most buildings in East Africa are constructed as reinforced concrete framed structures with strong masonry infill, but during design, engineers assume that the masonry infill panels have zero contribution in offering load resistance. Due to the problem above, a study with an objective of finding out the influence of masonry panels on the properties of reinforced concrete infilled frame under vertical load has been done. Three types of models: reinforced concrete frame model, masonry model and reinforced concrete frame with masonry infill, were investigated using finite element technique. In additional to the finite element analysis, laboratory models were prepared and tested so as to check the validity of the analytical results. The obtained results have led to an establishment of a mathematical model which may be useful to the design engineers since masonry wall panels can now be considered as load bearing elements. Such consideration of frame together with masonry leads to an accurate and optimal design of the frame, resulting into lesser amount of reinforcement and geometrical properties of the frame.
文摘The research presented in this paper deals with the seismic protection of existing frame structures by means of passive energy dissipation. An iterative displacement-based procedure, based on capacity spectrum, to design dissipative bracings for seismic retrofitting of the frame structures is described, and some applications are discussed. The procedure can be used with any typology of dissipative device and for different performance targets. In this work, the procedure has been applied, with both traditional pushover (load profile proportional to first mode) and multimodal pushover, to an existing RC (reinforced concrete) frame building. In the application, the buckling restrained braces have been used in order to prevent damages to both the structure and non structural elements. The use of multimodal pushover proves to be more effective than pushover based on single mode in case of medium rise RC frame building (higher than 30 m) but, once this building is retrofitted, and therefore regularized, with a bracing system, the difference between using monomodal or multimodal pushover becomes insignificant.