Manufacture of concrete with artificial sand from rice husk waste

Abstract

The high level of rice production in Indonesia creates a large amount of waste material as the husks are removed from the edible portion of the rice grains. Grain milling plants—located in almost every region of Indonesia—cause environmental pollution from the incineration of the unused husks. This study investigated the viability of reducing pollution by making effective use of the husks. Our goal was to determine the suitability of rice husk charcoal as a substitute for sand in the manufacturing of concrete. Testing included the weight of both solid and loose components, absorption, and strength. Rice husk was burned to form the charcoal. Cube-shaped concrete test objects were prepared with a size of 15cm x 15cm (up to 15 pieces) with a predicted compressive strength of 25 MPa. The mix design used Indonesian standard SNI 03-2834-2000. Our overall conclusion was positive. We obtained the following test results for the charcoal: weight of 0.581, density of solid contents 258.21 kg/m³, density of the loose contents 247.37 kg/m³, and absorption of 0.51. The compressive strength test of the concrete at 28 days yielded a strong press of 21.7 MPa; at 56 days this was 27.4 MPa; and at 90 days, 31.8 MPa. The Rat content was 2.150 kg/m³ when tested at 56 days and 90 days. Compressive concrete strength exceeded the projected value of 25 MPa, achieving a range of 27.4–31.8 MPa. The rice husk charcoal could be used as an effective substitute for sand and caused heavy concrete to become lighter.