New Model Of Enhanced Plasticity For Reinforced Concrete Structural Elements That Take Into Account The Effects Of Lateral Loading And Gravity

Reinforced concrete structures are exposed to a progression of activities all through their life expectancy which may be the purpose behind damage. Subsequently, rehabilitation of existing structures is typically performed either to restore structural limit because of decay or damage or to broaden existing structural limit due to expanded loads. To fortify existing structures, numerous new creative materials like progressed fiber-reinforced polymers (FRPs) are discovered to be acceptable substitute for reinforcing materials like steel. They are actualized to fortify the presentation of structural components in flexure, pivotal, shear, and twist. In a RC outline, migrating plastic pivots in the beam off from the column face is normally prescribed to broaden pliability of the edge. This could be accomplished through rib reinforced FRP retrofit of the joint. Furthermore, to it, thus we execute an expanded pliancy for the concrete structural components like column, beam, chunk, dividers then on. The primary motivation behind a wide range of structural frameworks utilized in the structure type of structures is to transfer gravity and horizontal loads effectively.

Experimental vs. Numerical Simulations: Seismic Response of a Half Scale Three-Storey Infilled RC Building Strengthened Using FRP Retrofit

Background: In the field of seismic analysis of structures, the use of appropriate Finite Elements software packages to manage more complex numerical models and to run more sophisticated analyses (such as nonlinear dynamic time-history analyses) in very short runtimes has increased significantly in the last decades. In order to have confidence in the numerical results of these complex analyses, it has become an increasingly widespread practice to verify and validate the FE computers programs against literature case studies as well as experimental results. Focusing on this latter aspect, shaking-table experiments on real buildings play an important role in understanding the actual behaviour of such structures. Objective: In the present work, the numerical evaluation of the seismic response of a half scale three-storey infilled RC building that has been strengthened using composite materials (i.e. FRP retrofit) is carried out by adopting specific modelling techniques. The adequacy of the numerical modelling is then verified by comparing numerical results against experimental data.

EFFECT OF FLY ASH CONTENT IN MBC BONDER FOR SUSTAINABLE CFRP RETROFIT

The rehabilitation and strengthening of reinforced concrete structures have been attracting increasing attention due to various factors including increase in traffic volume and weight, structural aging and environmental impact. Various techniques such as grouting, guniting and external post-tensioning are being used to retrofit or strengthen deteriorated members. With recent developments in the application of fiber composites in structural engineering, externally bonded Fiber Reinforced Polymer (FRP) system has become one widely used repair techniques because of its durability and long-term cost-effectiveness. In the FRP bonded retrofit technique, epoxy is often used as the bonding material. Because of environmental impact and health issues, construction sector is always looking for sustainable alternative bonding materials for FRP retrofit. A new trend on using Mineral Based Composites (MBC) has garnered the attention for a possible alternative to replace the use of harmful epoxy in FRP retrofit. MBC is formed by mixing the cement with some other minerals together and some concrete admixtures. As a part of a project to investigate optimum mix for the MBC, a series of tests were carried out to study the effect of fly ash content in the MBC mix as a partial replacement of cement. This paper discusses the results from this experimental program and evaluates the optimum fly ash content for the MBC and its associated properties.

Experimental Research on Seismic Behavior of Seismically Damaged RC Frame Column Strengthened with Sprayed Hybrid BF/CFRP

This experimental program was designed for investigating the seismic behaviors and strengthening effect of pre-damaged RC frame columns retrofitted with sprayed BFRP and hybrid BF/CFRP. Four RC frame column specimens, among which one was unstrengthened and three was pre-damaged and strengthened with sprayed FRP, were tested under an incremental loading procedure of the pseudo-static, cyclic shear loads combined with constant gravity loads. The test results including the failure mode, ultimate bearing load capacity, load-displacement hysteresis curves and ductility of specimens were obtained and analyzed. It indicates that spraying hybrid BF/CFRP strengthening scheme can effectively improve the ductility and energy dissipation ability of pre-damaged concrete frame columns. Although the improvement of the peak loads and ultimate lateral deformation of damaged frame columns were not obvious compared with those of the reference column, but it should be pointed out that the strengthened columns were pre-damaged seriously with yielded steel bars and the recover of load bearing ability resulted from spraying FRP retrofit can not be neglected. It also shows that increasing the thickness of spraying overcoat can effectively improve the energy dissipation ability of damaged frame columns.