Influence of the porosity and pore size on the compressive and splitting strengths of cellular concrete with millimeter-size pores

Cellular concrete with millimeter-sized pores has recently been suggested as an attractive material in engineering fields because of its specific material properties. However, few studies have assessed the effects of porosity, pore size and their interaction on the splitting tensile strength of cellular concrete. A comprehensive understanding of the mechanical properties of cellular concrete is needed prior to its application in engineering. The effects of porosity (0, 5, 10, 15, 20, 25 and 30%) and pore size (0, 1, 4.5, 7.5, 9.5 and 12.0 mm) on the segregation, compressive strength and splitting tensile strength of cellular concrete fabricated using a saturated superabsorbent polymer (Sat-SAP) and their relationships are investigated in this study. The incorporation of SAP significantly increases the segregation characteristic of cellular concrete. The segregation is particularly high for porosities higher than 15%, and the lowest segregation is observed for pore sizes of 4.5–7.5 mm. The compressive and splitting tensile strengths of cellular concrete decrease gradually with increasing porosity and pore size, but the effect of pore size on the mechanical properties of cellular concrete is very weak at pore sizes greater than 9.5 mm and porosities less than 10%. Moreover, a modified method for describing the stress-strain curve and calculating the elastic modulus of cellular concrete is suggested. Based on these results, some empirical formulas are proposed or modified to better analyze the segregation characteristics, accurately describe the stress-strain curve, and effectively predict the mechanical properties of cellular concrete with different porosities and pore sizes and their relationship.