Dec 10, 2015· M20 grade concrete mix meet this requirement when M-sand is used as fine aggregate. Bond strength 13.9 MPa for river sand and 14.1 MPa for M-sand Stress-strain characteristics of concrete The strain corresponding to peak stress is 0.0017 and 0.0021 for the concrete using river sand and M-sand respectively. Compressive and flexural strength of ...