ASSESSMENT OF THE CONTENT OF STONE FINE POWDER AND RAW RICE HUSK IN HIGH-PERFORMANCE LIGHTWEIGHT RICE HUSK CONCRETE BLOCKS

Abstract

Stone fine powder (SFP) as a solid by-product of the stone-cutting industry and raw rice husk (RRH) as a large-tonnage waste left from rice production often cause land pollution in the surrounding areas. This research aims to investigate the optimal use of  SFP and RRH as raw materials in the manufacturing of lightweight material of SFP-based rice husk concrete blocks (RHCBs) associated with the different performances of RHCBs. The RHCBs were composed of three materials: cement (binder), SFP, and RRH. To assess their performances, samples were grouped into three batches of binder-RRH ratios and in each batch, there were six binder-SFP ratios, resulting in a total of 18 concrete mixes. The results have revealed that the increase of the SFP content in concrete mixture significantly enhances the density and compressive strength of SFP-based RHCBs, due to their denser structure. This best synergetic ratio in a lightweight concrete mixture of SFP-based RHCB  is 1 binder : 1 SFP : 3 RRH, with a density of around 1,345.27 kg/m³ and a compressive strength of approximately 2.80 MPa. The findings will contribute to the forthcoming paradigm shift of using SFP and RH in concrete, which will decrease the environmental impacts.