Sustainable Concrete with Rice Husk Ash (RHA) for Marine Structures Francisco A. Martinez Urtecho, Luis J. Oyanguren Gallo, José U. Rodriguez Barboza and Elsa Carrera Cabrera MATEC Web Conf., 303 (2019) 05002 Published online: 12 December 2019 DOI: 10.1051/matecconf/201930305002