Mechanical Properties of Concrete Blended with Rice Husk Ash, Oyster Shell Powder, and Ferrous Powder

Due to emerging global environmental awareness, the increasing demand on synthesizing green materials for structural purposes became prevalent. This study utilized agricultural, aquacultural, and industrial waste as partial replacement for fine aggregates in concrete. One standard and six concrete samples with various proportions (20% and 40%) of rice husk ash (RHA), oyster shell powder (OSP), and ferrous powder (FeP) were constructed and tested for their mechanical properties (i.e., compressive and split tensile strength). The samples containing 20% and 40% FeP attained the highest compressive (22.71 MPa) and split tensile strength (1.379 MPa), respectively, which are closest to the control, M25 grade concrete (C-M25), (23.87 MPa), and (1.44 MPa), respectively. Concrete fracture analysis indicated that the cylinders were well constructed as implied by the fracture types. The C-FeP is the best concrete mixture attaining superior compressive and split tensile strength values.