In the case of construction quality control, construction rework, when left unnoticed, can span up to 25% of the total contracted construction cost, create significant delays (Berlin Airport), or much worse cause structural instabilities (Eindhoven Airport) and possibly fatalities (Neurath power station scaffolding). Reliable, and frequent collection and analysis of relevant field data are, hence, necessary to reduce the adverse effects of rework in construction. 3D point clouds provide a strong basis for fabrication dimensional verification as well as tolerance checks to help detect rework and possible structural instabilities. The frequent collection and analysis of 3D point clouds of construction elements is, hence, imperative to mitigate the risk associated with catastrophes, such as structural failure as well as late detection of rework. The following video provides an ethical perspective on the roles and responsibilities of digital engineering and construction practitioners in devising innovative solutions to utilize the latest technologies, particularly when the subject of construction safety is of the essence.

Quality control using point clouds is applicable both for prefabricated construction as well as in-situ construction. In terms of prefabrication of large mega projects in remote or cold environments, typically large modules are built in controlled manufacturing facilities and shipped to site. In the case of oil and gas projects, these modules consist of many pipes and flanges, which once shipped to site must be joined together at the flanges. Hence, an effective and fast method is required to collect point clouds of these modules and verify the fabrication quality of the flanges before and after they are shipped to site. One successful framework for fabrication verification of oil and gas modules is shown in the image on the left, derived from Maalek et al. (2019).

The aforementioned process presents a new method for cylinder detection from point clouds for the purpose of fabrication verification. In addition to the oil and gas refinery case for module fabrication verification, the method was shown to be effective in the quality control of anchor bolts, which are commonly utilized for prefabricated concrete and steel building construction projects. The following video provides a brief description of the method and related results.

Journal:

1. R. Maalek, D. D. Lichti, R. Walker, A. Bhavnani, and J. Y. Ruwanpura, “Extraction of pipes and flanges from point clouds for automated verification of pre-fabricated modules in oil and gas refinery projects,” Automation in Construction, vol. 103, pp. 150–167, July 2019, doi: 10.1016/j.autcon.2019.03.013.

Conference:

1. R. Maalek, D. D. Lichti, and J. Y. Ruwanpura, “Development of an automated 3d/4d as-built model generation system for construction progress monitoring and quality control,” The CSCE International Construction Specialty Conference, June 2015, Vancouver, BC, Canada.

Media:

1. Winner of the Alberta Science and Technology (ASTech) awards for Outstanding Achievement in Applied Technology 2018. https://www.astech.ca/archives/indexofpastwinners/automated-monitoring-control-system-group