Experimental Characterization of Mycelium-Based Composites Under Multiple Loading Conditions

Abstract

The increasing demand for environmentally sustainable materials in the construction sector has led to growing interest in mycelium-based composites (MBCs). These materials are primarily used in non-load-bearing applications, and their mechanical behavior remains insufficiently characterized under multiple loading conditions. This study experimentally investigates the mechanical response of unpressed and hot-pressed MBCs under compression, shear, and tension. Mechanical testing was complemented by digital image correlation (DIC), scanning electron microscopy (SEM), and micro-computed tomography (Micro-CT) to examine deformation behavior, failure modes, and internal structure. Under the present test conditions, hot pressing was associated with higher measured compressive and shear stiffness, with increases of about 64% in compressive modulus and 111% in shear modulus. In this study, the measured shear strength also increased by about 240%, although it remained low. In contrast, lower tensile properties were measured for the hot-pressed specimens, with tensile modulus and strength decreasing by about 65% and 13%, respectively; however, the tensile results are based on a limited sample size (n = 2). The hot-pressed compressive strength was not measured to failure because of load cell limitations. Overall, the present findings indicate that the current mechanical performance remains limited, particularly in shear.