Title: Lightweight Foamed Concrete Mixture for Structural Use
Author(s): Rabab Allouzi, Aya Al Qatawna, and Toqa Al-Kasasbeh
Publication: Materials Journal
Appears on pages(s): 99-109
Keywords: foamed concrete; mechanical properties; polypropylene (PP) fibers content; structural use; workability
Foamed concrete is currently studied to investigate its feasibility to be used structurally to produce a lightweight concrete mixture that is workable and has sufficient mechanical properties. This encouraged this research to design a foamed concrete mixture to be used in the construction industry. The main parameters that shall be satisfied for structural use are the workability, density less than 1900 kg/m3, and minimum cylinder compressive strength of 17 MPa (2500 ksi) based on ACI 213R. In this paper, 14 different foamed concrete mixtures are designed and tested to investigate their applicability. As fly ash quality affects foamed concrete permeability and as foamed concrete has low resistance to concentrated stresses, the proposed mixtures do not contain fly ash and are reinforced with polypropylene (PP) fibers. The effect of water-cement ratio (w/c), sand-cement ratio (s/c), PP fibers content, and the foam agent content are investigated. It is found that the compressive strength increases with the increase in density. The optimum s/c is 1:1, w/c is 0.4, and the PP fibers content is 1% by weight of cement. A relationship of splitting tensile strength relative to compressive strength is proposed.