Mechanical properties of 3D printed mortar cured by CO2

Abstract

Three-dimensional (3D) printing technology has received significant attention in construction building areas, and CO2 curing has been proven to be an effective method to enhance the properties of cementitious materials and sequestrate CO2. In this study, the mechanical properties of 3D printed mortar (3DPM) which had been subjected to CO2 curing were investigated. The effects of curing time and the interlayer bonding types on the mechanical properties were discussed. The results show that appropriate CO2 curing improved the mechanical properties of hardened 3DPM, especially the early age property, and the enhancement showed significant anisotropy in different test directions. In addition, the carbonation depths of the interlayers were higher than that of printed strips. Increasing carbonation time reduced the differences between the interlayer and strips’ carbonation depths. Moreover, the carbonation extent of 3DPM was evaluated, and it was found that with an appropriate printing setting, the maximum carbonation ingression of 24% was attained in 24 h CO2 curing.