Automated locating of replaceable coupling steel beam using terrestrial laser scanning

The replaceable coupling steel beam (RCSB) is an optimal component of earthquake-resilient structures. In practice, the RCSB is connected to RC shear wall using numerous bolts with a small construction tolerance of 2 mm. However, conventional methods to locate the bolt holes are mainly manual and rely on an approximate measurement, thus time-consuming and subjective. Addressing this issue, this paper describes a fully-automated method to locate the bolt holes in RC shear walls using the terrestrial laser scanning. Specifically, the bolt holes can be first detected by an effective boundary detecting technique and then accurately fitted with a robust random sample consensus algorithm. The proposed technique is validated with the experimental results including the radius and relative position estimations of bolt holes. The fully-automated method can therefore be adopted to locate the RCSBs.