# The Integration of Earthwork Design Review and Planning Using UAV-Based Point Cloud and BIM
###### Abstract
It is still true that the traditional GNSS surveying or total station methods can detect errors in earthwork design; however, what is different from the traditional approach is that UAVs have the capability of creating a site map on the fly and increase the efficiency of the design review process. As addressed in previous studies, further research that can exploit the result of UAV-based point cloud should be proposed, and considering the practical goal of the earthwork is cost-saving, and considering that the most of cost in earthwork is for equipment such as excavator, dump truck, and so on, with the help of UAV [8]. Although the earthwork design (i.e., shaping original ground to finishing grade) and planning (i.e., determining equipment combinations and its work sequences) are highly interconnected and mutually rely on each other, there is a notable paucity of studies that seek to connect earthwork design review and planning using advanced technologies. Up to now, there have been no attempts to link the earthwork planning sequence. Some evidence suggests that BIM can play an important role to optimize earthwork planning [9], while further work using BIM and UAV-based point cloud is still required to confirm this finding. And comparatively few studies have examined the usability and efficacy of implementing UAV in earthwork design. However, to be able to fully implement the UAV-based design intervention, a seamless integration toward earthwork planning is essential considering that most of the earthwork process is performed by heavy machinery. This study set out to gain further understanding of UAV-based 3D point cloud map and BIM in the construction industry by seamlessly integrating the earthwork design review and earthwork planning. This study incorporated real data from a housing construction project in Korea to prove the feasibility of the integration process of UAV-based 3D point cloud map acquisition to BIM-based earthwork planning using Autodesk Civil 3D and an excavator task planning strategy. The housing project includes 2D cut and fill earthwork and building pad design. Design verification through UAV photogrammetry, earthwork allocation, excavator implementation, etc. To illustrate the process of the integration of earthwork design review and planning with UAV-based 3D map, this study adopted a task planning strategy that is previously developed by our research team [1], to gain an insight into whether the proposed integrated process is feasible. The task planning strategy employs a Complete Coverage Path Planning (CCPP) algorithm for the operation of an excavator, and it generates a sequence of excavation areas while considers work environments such as the location of the entrance, moving distance, the geometry of the terrain, etc. The overall structure of this paper takes the form of 5 sections. Section 2 gives a review of the trends of earthwork design review, UAV, and BIM. Section 3 describes the study area, research methodologies on how the design review and planning process can be improved using UAV-based point cloud data as well as BIM; then the results, discussion, and conclusion will follow.