Flanged shear walls are used extensively in moderate- and high-rise buildings to resist lateral loads induced by earthquakes. The seismic performance of many buildings is, therefore, closely linked to the behavior of the reinforced concrete walls. They must be carefully designed to provide not only adequate strength, but also sufficient ductility to avoid brittle failure under strong lateral lo...

The strength and ductility of concrete improve under multi-axial compressive stress due to confinement effect. Some parameters are effective for considering the confinement in concrete and various stress-strain models were developed by different researchers. Longitudinal and transverse reinforcement steels can influence on confinement in reinforced concrete members. In this paper, various stres...

reliable stress-strain behavior of concrete is necessary particularly when a member is subjected to combine bending and axial load and confinement effects should be accounted for. a unified theory for confinement of circular hollow sections is proposed herein, that can be extended to the case of solid and noncircular sections. the main aim of the model is to trace step-by-step the evolution of ...

In recent years application of CFRP sheets in the strengthening of the concrete circular column has increased numerously. Knowing the exact behavior of concrete cylindrical columns confined with CFRP is of the first order of importance. ISIS Code of Canada has given relations for strength increase of circular columns confined with CFRP sheets, these relations are defined for a specified range o...

the use of polymer composite (frp) as a reinforcement material for the repair and strengthening of important components of reinforced concrete structures, particularly columns, has found wide spread. in this study, the effect of intermediate layer on improving the confinement behavior of reinforced concrete columns has been investigated. to achieve the objectives of the study, 14 cylindrical re...

a r t i c l e i n f o Keywords: Concrete-filled steel tube (CFST) Confinement effect Fuzzy logic Modified learning from example (MLFE) Axial load capacity A circular concrete-filled steel tube (CFST) has several advantages compared with the conventional reinforced concrete member or hollow steel tube, since the tri-axial state of compression of the concrete infill increases its strength and str...

a comparison between design codes i.e. aci and aisc-lrfd in evaluation of flexural strength of concrete filled steel tubular columns (cfts) is examined. for this purpose an analytical study on the response of cfts under axial-flexural loading is carried using three-dimensional finite elements with elasto-plastic model for concrete with cracking and crushing capability and elastoplastic kinemati...

This paper presents an experimental study on circular stirrup-confined concrete specimens under uniaxial and monotonic load. The effects of stirrup volume ratio, stirrup yield strength and concrete strength on damage evolution of stirrup-confined concrete were investigated. The experimental results showed that the strength and ductility of concrete are improved by appropriate arrangement of the...

one important application of fiber reinforced polymer (frp) is to confine concrete as frp jackets in seismic retrofit process of reinforced concrete structures. confinement can improve concrete properties such as compressive strength and ultimate axial strain. for the safe and economic design of frp jackets, the stress-strain behavior of frp-confined concrete under monotonic and cyclic compress...

During recent years, the use of fiber-reinforced polymers (FRP) as a desirable alternative for improving the behavior of lateral resisting system are known. There are various factors influencing the quality of such kind of rehabilitation. This study aims to investigate the influence of geometric characteristics and arrangement of FRP layers on rehabilitating of concrete shear walls.  A few rein...