NGHIÊN CỨU SẢN XUẤT BÊ TÔNG BỌT VỚI CÁC HÀM LƯỢNG CÁT KHÁC NHAU

Abstract

This paper presents an investigation on the physical and mechanical characteristics of foamed concrete with various sand contents of 25%, 50%, 75%, and 100% amount of binder. Four mixtures were designed with a bulk density o f1050 ± 50 kg/m3,fly ash content was 20% amount o f binder and the water-to-binder ratio was 0.2. The experimental results showed that the bulk density, compressive strength, ultrasonic pulse velocity, and thermal conductivity o f the foamed concrete samples gradually increased and reached the maximum value when the sand content increased to 75%, while the water absorption gradually decreased. However, when the sand content increased to 100%, the bulk density, compressive strength, ultrasonic pulse velocity and thermal conductivity o f the foamed concrete samples decreased slightly, while the water absorption o f the concrete samples increased slightly again. In this study, the sand content equal to 75%) amount o f the binder was the optimal value, the corresponding sample had a compressive strength of 6.17 MPa and water absorption o f 6.58%. All foamed concrete produced in this study can be used as unburnt bricks with lightweight and good thermal insulation.
Keywords: Foamed concrete, fly ash, sand content, compressive strength, bulk density, water absorption, thermal conductivity.