Identification of Geotechnical-Related Factors Impacting Cost, Schedule, and Claims on Roadway Construction Projects

Abstract

In construction projects, changes are inevitable and impact cost, schedule, and claims. There are limited studies on geotechnical investigations of factors affecting cost, schedule, and claim increases on the US roadway paving projects. This study’s primary objectives are to assess design standards and subsurface investigation techniques, explore the influence of geotechnical change orders (COs) on cost, schedule, and claim increases, and determine the appropriate cost for geotechnical investigation for roadway paving projects. Survey data was gathered from 53 individuals at the Department of Transportation (DOTs) and 43 consulting engineers. To rank the factors, the relative importance index (RII) was utilized, and Mann-Whitney U tests were conducted to see the differences between the groups since the data sets were not normally distributed. The results demonstrate that the six most important geotechnical COs that have an impact on cost, schedule, and claim increases were sub-grade mischaracterized or misclassified, higher ground water table than anticipated, design change in roadway pavement, insufficient borings, unsuitable soil remediation technique for specific site, and dewatering because of seepage issues. The group of six factors were statistically significantly different than the group of three other factors. The results also show that the appropriate geotechnical investigation cost should be at least three percent of the total project construction cost. In addition, this study also prioritized recommendations to lower the project costs, schedule delays, and claims. The findings may assist DOT engineers in taking measures to prevent cost, schedule, and claim increases, but their application is limited to roadway pavement projects. The practical implication of this study’s findings is that the DOTs can mitigate the major impacts of geotechnical COs on project cost, schedule, and claim increases that are related to roadway projects. Utilizing the study findings, state DOTs and consulting engineering firms can reduce the negative impacts of geotechnical COs in future roadway pavement projects. Focusing on the leading causes of geotechnical COs, cost, schedule, and claim increases, private consultant firms can improve geotechnical designs, which may help reduce cost and schedule overruns in future projects. The study findings also provide key recommendations that are to be conducted before the construction phase of a roadway project to reduce geotechnical COs and their negative impacts. Since this study focuses on roadway projects, the DOTs should take caution while applying their findings to other construction projects.