Mechanical properties of non-autoclaved foam concrete: analytical models vs. experimental data

Abstract

In this paper, we focus on the mechanical characterisation of non-autoclaved foam concrete according to its macro porosity (foam volume fraction). Firstly, five densities of foam concrete ranging between 600 and 1400 kg/m³ have been designed and then made by varying the volume fraction of a pre-formed organic foam within the same mortar matrix. Secondly, this range of foam concrete has been characterised experimentally by measuring their Young’s moduli and their compressive and flexural tensile strengths. Based on these experimental results, it has been confirmed that foam concrete mechanical properties decrease with the increase of its macro porosity. Besides, analytical models have been identified to predict foam concrete mechanical properties according to its macro porosity. In fact, it has been found that the Young’s modulus and the compressive strength of foam concrete can be well predicted according to its macro porosity by Balshin type power laws. Moreover, it has been shown that a Shiller type exponential law gives a good prediction for the foam concrete flexural tensile strength. Finally, it has been observed that foam concrete tensile failure becomes less brittle when its macro porosity increases.

Keywords:

• Foam concrete
• macro porosity
• Young’s modulus
• mechanical strengths
• experimental tests
• analytical modelling

Acknowledgement

The authors gratefully acknowledge the financial support for this research by the Tunisian company ‘M.A.N Béton’ specialised in the production of non-autoclaved foam concrete. A special acknowledgement for Mr. Nacchache the head of this company for his support to the experimental programme.