Influence of the technological properties of cement-sand mortar on the quality of 3D printed products
Rustem Mukhametrakhimov, Liliya Lukmanova
Abstract
Abstract The results of the influence of cement-sand mortar mobility on quality of hardened composites, made by 3D concrete printing (3DCP), are presented. Four formulations of cement-sand mortar mixes with mobility classes P k 1, P k 2, P k 3, P k 4 which corresponds to immersion depth of the reference cone of 3.3 cm, 6.5 cm, 8.7 cm, 12.0 cm, respectively, were prepared for testing. It has been established that regulatory framework regulating 3DCP test methods not sufficiently developed and requires further improvement. It was revealed 3D printing of cement-sand mortar mixes with mobility classes P k 2-P k 4 on researched 3D printer is possible, however, products have defects and damages. Mortar mobility has a significant impact on structure kinetics and geometric parameters deviation. The lower mobility class is, the higher structure kinetics of raw material mix is, which is due to the early formation of the crystallization structure of hardened composite. Cement-sand mortar with class mobility P k 2 accepted for further research in the development of adapted raw mixes for 3DCP.