Eco-concrete hybrid blocks of styrofoam beads/modified palm kernel shell using cement or carbonized rice husk as a binder for construction components

The current study is focused on the fabrication of eco-concrete hybrid blocks using aggregates of styrofoam beads (SB) and modified palm kernel shell (MPKS) with cement (CEM) or carbonized rice husk (CRH) as binder. Prior research has focused on using animal wastes, polymer wastes, and agro-waste as aggregates in the fabrication of building materials, either in combination or alone with resultant low or average mechanical properties. In this study, we have combined the admixtures of SB and MPKS (varied ratios of 05:95, 10:90, 15:85, and 20:80) in CEM or CRH to fabricate SB/MPKS/CEM or SB/MPKS/CRH hybrid blocks. The block samples were designated as (CEMA¹, CEMA², CEMA³, and CEMA⁴) or (CRHC¹, CRHC², CRHC³, and CRHC⁴), respectively. The samples were tested for water absorption, bulk density, hardness, flaking, compressive strength and morphological properties. The results from the tests showed that the different ratios of (SB/MPKS/CEMA¹) hybrid blocks, particularly at 05:95 had better properties compared to the results obtained for corresponding SB/MPKS/CRHC¹ hybrid blocks. Bulk density, hardness and compressive strength of 2.5 g/cm³, 78.1 HV, and 63.7 N/mm² were achieved, respectively.