Inverse engineering approach to determine the elastic properties of lightweight expanded clay. (20th August 2019) - Carneiro, V.H.
Highlights: Inverse engineering is used to define the elastic constants of spherical porous solids; LECA diameter has a predominant role in the value of the Young's Modulus; The effect of diameter is not significant on LECA Poisson's ratio; Elastic properties are strongly dependent on sphere skin relative thickness. Abstract: Lightweight Expanded Clay (LECA) particles are aggregates processed by high-temperature gas infiltration and expansion of solid clay, being used to fill concrete and aluminum composites. Although, the properties of these composites are thoroughly researched, there are scarce studies on the properties of LECA itself. The referred studies are commonly based on indirect measurements and homogenization techniques. This study reports an approach, based on inverse engineering, to determine the elastic properties of these cellular materials. FEA routines are used to determine the fundamental elastic constants of modeled LECA spheres in uniaxial compression. These routines are posteriorly run in updating routines and compared with experimental data to estimate values of Young's Modulus and Poisson's ratio. It is reported that particle diameter has a relevant role due to the variation on the ratio between outer skin thickness and porous inner structure. The Young's Modulus of particles with 5.08, 7.59 and 10.65 [mm] with diameter are determined to be, respectively, 200, 280 and 640 [MPa]. The Poisson's ratio of the referred particles is estimated to be 0.34, 0.36 and 0.36.