A sandwich composite comprising ferrocement skins was developed as the primary structural module for building construction with indigenous materials. The indigenous reinforcement systems selected for use in ferrocement skins were jute burlap and chicken mesh (flexible galvanized steel wire). These reinforcement systems were characterized through performance of tension tests. The tensile strength, stiffness and ductility of jute burlaps were found to compare favorably with those of chicken mesh which is a viable reinforcement for use in ferrocement. Tension tests on ferrocement sheets indicated that indigenous reinforcement ratios above a threshold level could induce multiple cracking and strain-hardening behavior, producing a desired balance of tensile strength and ductility. The tensile strength of indigenous ferrocements with jute burlap reinforcement exceeded the theoretically predicted values, which could be attributed to the favorable interactions of the burlap reinforcement with the inorganic matrix, and the strengthening effects of hydrates precipitating within the yarn voids in burlap. Experiments were conducted to determine the bond strength and the required development length of the indigenous reinforcement in cementitious matrix. Indigenous sandwich composites comprising ferrocement skins with jute burlap reinforcement and an aerated concrete core made of lime-gypsum matrix and saponin foaming agent were fabricated and subjected to flexure testing. The sandwich composite provided relatively high flexural strengths; the flexural failure modes indicated that the relatively dense aerated concrete core makes important contributions to the flexural performance of the sandwich composite.

Aerated concrete materials were developed with abundant natural materials. Aerated concrete can provide insulating qualities complemented with secondary structural attributes when used as core in sandwich composites for building construction. A hybrid binder that comprised lime and gypsum was used. Different foaming agents were considered for production of aerated concrete, including saponin that is found abundantly in different plants. Different formulations were considered, and the stability of the foam structure as well as the density and early-age compressive strength of the resulting aerated concrete were evaluated. One formulation comprising lime-gypsum binder with saponin foaming agent, with a density of 0.53 g/cm3, was further characterized through performance of thermal conductivity, split tension, flexure, elastic and shear modulus and sorptivity tests. The results pointed at the satisfactory balance of qualities provided by the aerated concrete when compared with alternative aerated concrete materials.