S. Gopinath, A. Ramachandra Murthy, D. Ramya and Nagesh R. Iyer
This paper presents the details of optimized mix design for normal strength and high performance concrete using particle packing method. A critical review of mix design methods have been carried out for normal strength concrete using American Concrete Institute (ACI) and Bureau of Indian Standards (BIS) methods highlighting the similarities and differences towards attaining a particular design compressive strength. Mix design for M30 and M40 grades of concrete have been carried out using ACI, BIS and particle packing methods. Optimization of concrete mix has been carried out by means of particle packing method using EMMA software, which employs modified Anderson curve to adjust the main proportions. Compressive strength is evaluated for the adjusted proportions and it is observed that the mixes designed by particle packing method estimates compressive strength closer to design compressive strength. Further, particle packing method has been employed to optimize the ingredients of high performance concrete and experiments have been carried out to check the design adequacy of the desired concrete compressive strength.
K.V. Venkatesha, S.V. Dinesh, K. Balaji Rao, B.H. Bharatkumar, S.R. Balasubramanian and Nagesh R. Iyer
This paper presents the results of experimental investigations on six reinforced concretebeams, with three different shear span-to-depth ratios, which were tested under two-pointloading. The aim of the work was to study the efficacy of Carbon Fibre Reinforced Polymer(CFRP) strips in enhancing shear capacity and/or changing the failure mode from brittleshear failure to ductile flexural failure. The results of the study indicate that while thereis a marginal increase in first crack and ultimate loads, it is possible to achieve a changein the failure mode, and the monitored strain gauge data can be used to explain the failurepattern observed.