Experimental study on buildability and mechanical properties of 3D printing cob

Abstract

Abstract The application of 3D printing technology to earth buildings conforms to the development concept of low carbon, green and intelligent construction. The key issue lies in the development of earth material with both favorable buildability and sufficient mechanical properties. In this study, the printing parameters of mixture for 3D printing with different water contents were optimized. The optimum water content of 3D printing cob was determined based on the buildability. The result shows that when the flow spreading diameter is between 140 mm and 160 mm, 3D printing cob has good buildability performance. The optimum water content is 24.6%. In addition, anisotropic performance was analyzed by compressive strength tests from three orthogonal directions. In particular, according to the test results of single printing limit height and yield stress, the buildability of 3D printing cob wall was analyzed. The building strategy of the printing divided into multiple times was obtained.