IDOT uses modern technology in construction staking of Illinois highway projects

In a world that is increasingly shaped by improving digital technologies, the past few decades brought great advances in technology for highway construction and engineering. Such advances almost always aim to reduce costs and improve quality. For instance, incorporating technologies, such as the global-positioning system (GPS) and civil information modeling (CIM), among others, in highway construction is believed to lead to improvements in construction quality while reducing construction time and cost.Adapting Construction Staking to Modern Technology is the title of a research study initiated by the Illinois Department of Transportation and the Illinois Center for Transportation for the purpose of developing written procedures to facilitate the use of modern technology in construction staking of highway projects in Illinois.

“Technology can help the construction industry make huge strides in increasing quality and safety and reducing time and cost”, says the project’s Principal Investigator Nora El-Gohary, Associate Professor in the Department of Civil and Environmental Engineering at the University of Illinois at Urbana-Champaign.

The procedures developed within this project are intended for inclusion in IDOT’s Construction Manual, which “currently offers a construction staking policy that is based on surveying technology utilizing theodolites and levels, at the time when most staking that happens in the field is performed with GPS equipment,” according to IDOT’s Engineer of Construction Tim Kell, who chaired the Technical Review Panel overseeing the project.

Because the majority of contractors rely on automated machine guidance more than traditional grade stakes for their earthwork and paving operations, the study focused on drafting guidelines to IDOT’s construction staff for contract administration of automated machine guidance and construction layout utilizing GPS. “Using this technology provides for quicker layout and reduces the labor needed to perform the layout, thus leading to a reduction in construction costs,” says Kell.

The research team serving on the project, which was completed in August 2017, also included Professor Khaled El-Rayes, Associate Professors Liang Liu and Mani Golparvar-Fard, and Ph.D. candidate Ruichuan Zhang.

Information was gathered from DOTs and contractors on current practices employed by U.S. states that successfully adopted modern technologies for the construction staking of highways. Based on the collected information, a set of best practices were identified to guide the development of the written procedures. The research team further evaluated these best practices based on field investigations, as well as feedback from surveyors, engineers, and contractors in all nine IDOT districts. The written procedures cover important guidelines on: (1) evaluation of construction methods, (2) selection and maintenance of automated machine guidance (AMG) equipment, (3) development of AMG work plan, (4) training, (5) development of digital models, (6) exchange of electronic files, (7) project control, (8) accuracy and tolerance requirements, (9) construction spot checks, (10) site calibration and checks, and (11) final checks.

“The use of modern technologies, such as AMG and CIM, in construction staking can help save significant amounts of money and time on a job, so the payoff is relatively quick. These written procedures aim to provide the guidance needed to help employ such technologies effectively”, says El-Gohary.

The final report summarizing the findings of this study, including the written procedures, is available on ICT’s website.