Mechanical properties of plaster–Ferula Communis composites: insights from flexural, compressive, and vickers hardness analyses

Abstract

With the growing need to reduce energy consumption in buildings, improving the thermal behavior of construction materials has become essential in order to limit the reliance on energy-intensive systems for indoor thermal comfort. In this context, the development of sustainable and bio-based building materials represents a promising passive strategy for enhancing energy efficiency. This paper presents an experimental study aimed at providing thermophysical and mechanical characterization results of plasters reinforced with natural particles of Ferula Communis, along with an in-depth discussion of their mechanical performance. The objective is to assess, from a mechanical perspective, the potential of these composites to promote their application in construction. The results showed that incorporating Ferula Communis into the plaster matrix (from 0 to 8% by weight of plaster) significantly enhances thermal performance. Thermal conductivity and thermal diffusivity were reduced from 0.372 to 0.263 $$W/m \cdot K$$ and from 5.23 $$\times $$ 10 $$^{-7}$$ to 2.92 $$\times $$ 10 $$^{-7}$$ $$m^{2}/s$$ , respectively, highlighting the composite’s improved insulation capability. Conversely, this modification negatively impacts mechanical properties. Flexural strength decreased from 3.89 MPa to 2.15 MPa, while compressive strength dropped from 11.73 MPa to 2.25 MPa as the reinforcement content increased. Surface hardness, evaluated through Vickers indentation tests, also exhibited a gradual reduction from 10.80 HV (pure plaster) to 4.22 HV at 8% reinforcement. However, despite these reductions, the bending and compressive strengths remained acceptable according to EN 13279-2 requirements, and the hardness values were within an acceptable range up to 6 % reinforcement, ensuring sufficient surface durability for practical use. Consequently, the developed materials can be classified as lightweight gypsum composites, offering a balanced combination of thermal efficiency and mechanical performance suitable for non-structural building applications.