Strength and capillary water absorption of SB modified CSA cement mortar cured for 360 days under different conditions

The effects of curing conditions including temperatures (0°C, 5°C, 10°C, 20°C and 40 °C), relative humidities (30%RH, 60%RH and 90%RH) and outdoor curing on the strength and capillary water absorption of styrene‐butadiene copolymer (SB) modified calcium sulphoaluminate (CSA) cement mortar cured for 360 days were studied. The results showed that when the addition of SB reached 10% and more, the flexural strength increased and the capillary water absorption decreased significantly. Appropriate temperature and relatively high humidity were conducive to the development of flexural and compressive strength. The capillary water absorption increased with increasing temperature and decreasing humidity. Compared with curing under different temperatures and relative humidities controlled by laboratory, the modified mortar cured outdoors with more than 10% SB addition had higher strength and lower capillary water absorption.