Investigation of construction practices for Digital Terrain Models (DTMS) among state Departments of Transportation

Abstract

Digital Terrain Models, commonly known as DTMs, is a principal component of 3D models in construction projects. DTMs provide a digital topographic model of the earth's surface, with input from terrestrial and/or aerial surveying technologies. Departments of Transportation (DOTs) in the United States have implemented different practices to use DTMs in their highway and infrastructure construction projects. With the absence of studies tackling practices for construction-ready DTMs, it becomes important to understand and investigate how state DOTs vary in their deployment and implementation of DTMs in construction. To achieve this objective, data gathered from a nationwide survey was first used to cluster state DOTs into three categories based on their DTM experience in construction: beginner, moderate, and advanced. The two metrics used to categorize state DOTs were the total years of using DTM and the number of projects annually that use DTM. Then, nine DTM aspects were analyzed for the three state DOT categories, namely: sources, training, use cases, handover, project sizes, project types, project-specific benefits, long-term benefits, and challenges. Findings from this paper can assist state DOT professionals in (1) assessing their agency’s current level of experience with DTM in construction, and (2) providing them with a reference of what other state DOTs (whether with the same expertise level or higher) are doing so they can advance or “level up” their agency’s experience and further leverage the use of DTM in construction.