Preparation and Properties of Self-leveling Floor Mortar

By selecting and compounding different cementitious materials and chemical additives,three types of self-leveling floor mortar(SLM) with different binder systems were prepared.The effects of cementation system,aggregate gradation and additive on the properties of SLM were studied.The hydrated products of different binder systems and micro-structures of hardened pastes were investigated by X-ray diffractometry(XRD) and scanning electron microscopy(SEM).The results show that aluminate cement(AC) dominated SLM has better performances than that of Portland cement(PC) dominated SLM.It has the following features: quick-setting(hardened before 4 hours),accelerating strengthening(compressive strength at a curing age of 1 day is over 25MPa and at 28 days is over 40MPa),low-shrinkage(shrinking percentage at a curing age of 28 days is less than 0.05%),high-abrasion(rubbing abrasion at a curing age of 28 days is less than 0.30g);the strength of gypsum based SLM is improved significantly.Its dry compressive strength is over 30MPa and its volume change rate is less than 0.02%.