Modulus elasticity of the graded concrete, a preliminary researchM. Mirza Abdillah Pratama, B. Sri Umniati, Bunga Arumsari Mutiara Wulandari, Ay Lie Han, Buntara Sthenly Gan and Zhabrinna ZhabrinnaMATEC Web Conf., 195 (2018) 01005DOI: https://doi.org/10.1051/matecconf/201819501005