Experimental study on preparation and performance of the Corn Straw Fiber (CSF) reinforced EPS concrete

Abstract

With the full factor experimental design method carried out, 20 sets of EPS concrete specimens with different mass fractions of Corn Straw Fiber (CSF) and Expanded-Polystyrene (EPS) particles were designed to study their density, water absorption, compressive strength, flexural strength, splitting tensile strength, mass loss and strength loss after freeze-thaw cycles, and changes in thermal conductivity, to evaluate the effect of CSF content and EPS content on the properties of EPS cement-based composites. The experimental results show that adding CSF can improve the mechanical properties of EPS concrete while reducing its density, the maximum increase rate of compressive strength is 69.7 %, with a maximum value of 1.12 MPa; The maximum improvement rate of flexural strength is 127.38 %, with a maximum value of 0.885 MPa; The maximum improvement rate of splitting tensile strength is 68.07 %, and the maximum value is 0.256 MPa. After 50 standard freeze-thaw cycles, straw fibers can delay the quality loss of EPS concrete, but show adverse effects on its strength loss, the maximum quality loss rate is 4.23 %, and the maximum loss rates for the three strengths are 24.46 %, 24.22 %, and 24.61 %, respectively. In addition, in terms of improving the thermal insulation performance of EPS concrete, the role of the two aggregates is manifested as EPS > CSF, and the thermal conductivity coefficient values under different aggregate dosages were obtained, when the content of EPS is 1.4 % and the content of CSF is 4 %, the minimum thermal conductivity value is 0.0402 W/(m·°C), and the thermal conductivity coefficient of calcium silicate board is 0.0378 W/(m °C) by the thermal conductivity coefficient formula of composite materials. which can serve as a reference for selecting building insulation materials in areas with high temperature differences.