Non-contact sensing based geometric quality assessment of buildings and civil structures: A review

Geometric quality assessment (QA) of buildings and civil structures is an essential process in a construction project. Timely geometric QA is able to prevent construction delays and cost overruns, maintain the performance of in-service facilities, and extend their service life. Geometric QA based on manual measurement has been proven to be time-consuming, unreliable and costly. Therefore, non-contact sensing technologies have been widely deployed for more efficient and accurate geometric QA. While a large number of techniques and algorithms have been developed in previous studies for non-contact sensing-based geometric QA, relatively little work has been done to systematically study and review their performance. This study reviews recent research on non-contact sensing-based geometric QA of buildings and civil structures in three project phases: 1) manufacturing, 2) assembly/construction, and 3) operation/maintenance phase. For each phase, the geometric QA is further categorized based on different QA purposes, including dimensional QA, surface QA, and deflection/deformation QA. Based on collected papers, two parts of analysis, consisting of 1) the adoption of different sensors for different project phases and 2) the performance of the QA algorithms/methods, are discussed in detail. Following the literature review and in-depth discussions, research gaps and future research directions are suggested, including improvement of QA techniques in each project phase, improvement of QA techniques applicability, and improvement of photogrammetry accuracy. This technical review is expected to have not only academic value by suggesting technical research directions based on the research gaps, but also practical values that allow contractors and subcontractors to automate and improve their current geometric QA practice.