Potential of sandwich panels with lightweight bioconcrete core with palm oil shell residue for use in civil construction

Abstract

The use of sandwich panels in construction is a viable alternative in the search for materials with low self-weight, lower thermal conductivity, and resistance to compression. To increase the sustainability of this solution, it is necessary to replace the steel reinforcement of the faces and the EPS core with materials that have lower energy costs and reduce greenhouse gas emissions during production. In this context, this study aims to develop a sandwich panel with a lightweight concrete core made from oil palm endocarp as a substitute for conventional coarse aggregate and faces with mortar reinforced with short sisal fibers. The bioconcrete was produced with two levels of oil palm endocarp (100% and 150% of the binder mass) and two water/binder ratios, 0.35 and 0.45. The increase in the content of endocarp results in increased water absorption and reduced mechanical strength, but the panels had a specific mass lower than 1480 kg/m³ and compressive strength greater than 7 MPa, qualifying them for use as infill masonry. The use of sisal fibers allowed an increase in toughness under flexure even after the initiation of panel cracking.