Bond Performance Between Embedded Rebar and 3D Printed Mortar

Abstract

Abstract: In order to explore the feasibility of rebar embedding technology in 3D printed cement-based materials, this study conducted a series of pull out tests to investigate the influence of rebar embedding methods (pre-embedded, embedded), forming methods (pouring, printing), the angle between the printing bar and the rebar (0°, 90°), and bond length (5Ø, 7Ø, 10Ø, Ø is rebar diameter) on the bond performance between embedded rebar and 3D printed mortar. Comparative analysis was carried out on the ultimate load, relative slip between rebar and mortar matrix, and failure modes of different specimens. The results show that when the printing bar is perpendicular to the rebar, the best bonding effect is achieved using the rebar embedding method. The ultimate load of vertically printed embedded rebar specimens is 58.30% higher than that of pre-embedded rebar specimens. Under the rebar embedding method, the corresponding slip value of the ultimate load increases. Additionally, with the increase of the bond length, the ultimate load increases, but the increase becomes less significant when the bond length exceeds 7Ø, and the failure mode changes from splitting failure to rebar pullout. The study indicates that reinforcement with rebar embedding can significantly improve the bond performance between 3D printed mortar and rebar and enhance the deformation capacity of the specimens.

Key words: 3D printed mortar, embedded rebar, printing method, bond performance, pull out test, destruction mode

CLC Number:

TU528

ZHOU Xun, LIU Genjin, WANG Yinhui, LI Hedong, GENG Jian, XIE Weihong, NI Kun. Bond Performance Between Embedded Rebar and 3D Printed Mortar[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2024, 43(5): 1633-1641.

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