Comparison of pull-out capacities of robotically and manually drilled and set fasteners

The performance of post-installed fasteners in concrete can be affected by the chosen drilling and setting techniques. In the context of the development of a drilling robot for construction site implementation the impact of an automated setting process on the pull-out loads of fastening systems was evaluated. This article investigates the effect of two different fixing systems, drop-in expansion and chemical anchors, on the pull-out behaviour of manual and robotic drilling and installation. While for chemical anchors, the results indicate that robotic installation leads to similar pull-out forces with smaller deviation, expansion anchors in robotically drilled holes show slightly lower pull-out loads than those in manually drilled holes. Furthermore, a more uniform pull-out behaviour was observed for chemical anchors when set by the robot. In conclusion it can be shown that robotically set fasteners achieve a comparable performance, presenting a feasible automation approach for the construction industry.