Comparative study on Steel fibre reinforced Cum control concrete under flexural and deflection
Fibre reinforced concrete, a composition of concrete and fibres is being prominently used for various important applications. The hook tain steel fibres assist in controlling the propagation of micro-cracks present in the matrix, first by improving the overall cracking resistance the matrix and later by bridging across even smaller cracks formed after the application of load on to the member thereby preventing there widening into major cracks. In the present paper, the effect of steel fibre reinforcement with different percentage of fibre 0, 1%, 2% and 3% by volume for M-40 grade of concrete with aspect ratio 50, 60 and 67 are studied. The beam is tested for flexural strength. The percentage increase through utilization of steel fibers is reported. A relationship between aspect ratio vs. flexural strength represented graphically.
Experimental Study on the Flexural Strength of Fly Ash based Steel Fiber Reinforced Concrete in Different Aspect Ratios
Steel fiber and fly ash are common additives that can improve concrete performance. Steel fiber improves the tensile and flexural properties of concrete whereas fly ash acts as partial substitute for cement in concrete. This paper incorporates both the properties of steel fiber and fly ash. This project aims to investigate the flexural strength properties of steel fiber reinforced concrete with the addition of fly ash. The study is carried out in M25 mix. Steel fibers varied from 0%.0.5%,1%,1.5% of different aspect ratios 20 mm,30 mm and 40 mm and replacement of fly ash varies from 10%,20% and 30%. The specimens are generally tested for7 and 28 days and the behaviour of fly ash based steel fiber reinforced concrete were studied. The results are analyzed and compared with a control specimen. The specimens are tested for flexural strength. This project also aims to determine the optimum content of flyash and steel fiber that can produce the maximum flexural strength property. Keywords---Flexural strength, Aspect ratio, Volume fraction, Optimum content.
Mechanics of deformable directed surfaces
Abstract The paper develops a simple, yet complete and consistent non-linear dynamic thermo-elastic shell theory based on the concepts of a two-dimensional directed continuum. The constitutive equations are postulated in a general form. Stress-strain relations are derived using the equation of energy balance and the two entropy production inequalities, which are rewritten in a special form. The linear theory is discussed in detail. The structure of the stress-strain relations is presented in the most general form and then specialized to concrete examples, in particular, to the classical shell theory, using their invariance properties with respective to certain symmetry groups. The elastic moduli are determined by demanding the coincidence of the frequency dispersion surfaces obtained using the two-dimensional theory with the lowest foils of the corresponding surfaces resulting from the three-dimensional theory of elasticity.