11-09-2014, 03:54 AM
(06-08-2011, 03:09 PM)smart paper boy Wrote: Reinforced concrete structures often have to face modification and improvement of their performance during their service life. The main contributing factors are change in their use of ,new design standards, deterioration due to corrosion in the steel caused by exposure to an aggressive environment and accident events such as earthquakes .In such circumstances there are two possible solutions: replacement or retrofitting.
Retrofitting of flexural concrete elements are traditionally accomplished by externally bonding steel plates to concrete which has its own disadvantages of being susceptible to corrosion and difficult to install. Recent development in the field of composite materials, together with their inherent properties, which include high specific tensile strength good fatigue and corrosion resistance and ease of use, make them an attractive alternative to steel plates in the field of repair and strengthening of concrete elements.
Fibre reinforced polymer (FRP) composites consist of high strength fibres embedded in a matrix of polymer resin. Fibres typically used in FRP are glass, carbon and aramid. The primary functions of the matrix in a composite are to transfer stress between the fibres, to provide a barrier against the environment and to protect the surface of the fibres from mechanical abrasion The mechanical properties of composites are dependent on the fibre properties, matrix properties, fibre-matrix bond properties, fibre amount and fibre orientation.Mostly extensive research has been done in the past on strengthening of existing RC beams focusing on flexural strengthening. But the area of shear strengthening is yet to be cherished well .
It has been observed that new types of failures occur that can reduce the performance of FRP when used in retrofitting structures. These failures are often brittle, and include de bonding of concrete layers, delimitation of FRP and shear collapse. Brittle de bonding has particularly been observed at laminate ends, due to high concentration of shear stresses at discontinuities, where shear cracks in the concrete are likely to develop. Thus, it is necessary to study and understand the behaviour of CFRP strengthened reinforced concrete members, including those failures.
So I basically aim to work on the analysis of retrofitting of RC beams and study their behaviour especially under the shear properties under retrofitting. Software like Matlab and ANSYS can be used to find way to apply FRP as external reinforcement to enhance the shear capacity of RC beams by finite element method.
I strongly believe that you will be kind enough to give me an opportunity to get my self involved under the Surge program; under the able guidance of esteemed professors . I promise to contribute to the maximum of my ability.
