Mix Design of M-30 Grade Concrete for Rural Roads as per IRC44-2017

Abstract

This paper includes the mix design of M-30 grade concrete with specified characteristic Compressive strength of 30 N/mm2 for the road application as per IRC guideline (referring IRC44-2017 code). Since as per IRC-44, minimum grade of concrete is M30 for rural roads. So to begin with lower gradem, M30 mix design was preferred. Good quality of concrete can be achieved only by using the good quality of ingredient materials and properties of which should satisfy the recommendation of code. Basic Properties of ingredients obtained through laboratory tests are used in mix design. While designing the mix to set the W/C ratio, four mix trails are done to achieve 60mm slump by taking the permissible limit into consideration. In this work, super plasticizer is used as a chemical admixture to concrete to achieve the workability. To find the dosage of super plasticizer, Marsh cone test was done with a percentage of 0%, 0.25%, 0.5%, 0.75%, 1.0%, 1.25%, 1.5%, 1.75% and 2.0% to the weight of cement. For an each trail, cube of size 150x150x150mm are casted and compressive strength of each cube with respect 7, 14 and 28 days to curing was tested.