3D auxetic cementitious-polymeric composite structure with compressive strain-hardening behavior

Abstract

A composite can have properties much better than the components it is made of. This work proposes a three-dimensional auxetic cementitious-polymeric composite structure (3D-ACPC) which incorporates 3D printed polymeric shell with cementitious mortar. Uniaxial compression experiments are performed on the 3D-ACPC to study their quasi-static stress-strain response. Experimental results show that the created composite structure can simultaneously overcome the brittleness of conventional cementitious material and the low compressive strength of 3D printed polymeric cellular shell. Therefore, the 3D-ACPC exhibit compressive strain-hardening behavior ensuring high energy absorption ability. In addition, it is found that structural anisotropy and the shell printing direction have significant impact on the stress-strain response of the 3D-ACPC. Moreover, due to the lightweight cellular structure, the 3D-ACPC shows significantly enhanced specific energy absorption compared to conventional cementitious materials and polymeric cellular materials. To this end, the developed 3D-ACPC has great potential to be used in engineering practice, such as protective structures.