3D-printed concrete with in-process embedded fiber-reinforced polymer grid reinforcement

The absence of effective reinforcement has hindered the widespread use of 3D-printed concrete. In this study, we propose an innovative in-process embedding technology that enables the simultaneous printing of concrete and flexible fiber-reinforced polymer grids. We investigate the performance of grids as reinforcement in 3D-printed concrete through pull-out and splitting tensile tests to assess the bonding properties between the grids and concrete. Additionally, three-point bending tests were conducted to evaluate the impact of grids on the flexural performance of 3D-printed concrete plates. Test results show that the load-bearing capacity and deflection of 3D-printed concrete plates reinforced with grids increased by approximately 41% and 552%, respectively. However, the voids and reduced contact area caused by the simultaneous printing of the grids weakened the bonding between adjacent concrete layers. Overall, the findings confirm the feasibility of the proposed in-process embedding technology and demonstrate its protential to advance 3D-printed concrete structures through the effective integration of in-processfiber-reinforced polymer reinforcement. The lack of effective reinforcement has hindered the widespread use of 3D-printed concrete. The authors developed an in-process embedding technology for simultaneously printing concrete and flexible fiber-reinforced polymer (FRP) grids.