Applicability of Recycled Gypsum Composite Mortar as Raw Material for Foundation Work of Single-family Houses

AbstractThis study has confirmed the performance of a recycled gypsum composite mortar (RGCM) foundation, developed for the foundation work of a single-family house using a raw material recycled from waste gypsum boards generated from the construction of new buildings or the demolition of old buildings, equivalent or superior to that of existing foundation work methods. The compressive strength of an RGCM core sample depends on water content and the mixing cement ratio. It is 158 kN/m2for a high water/composite ratio (115%) sample after 28-days of air-drying, which is more than the maximum load of the sleeping foundation (50 kN/m2). The stress of the sleeping foundation can be transferred to the foundation ground. The hardening surface of the RGCM is smooth and there are no problems related to marking and joinability. Even when the excavated surface is rough, the RGCM can be used to fill the gaps resulting from its high fluidity, similarly to the SL material. Thus, the RGCM is integrated with the foundation ground. The RGCM foundation is advantageous from the viewpoints of environmental friendliness (recyclability), and is expected to be used as the foundation footing of houses.