Analysis of permit vehicles in Rhode Island

Sarju Mulmi, University of Rhode Island


This study assesses the capability of the current load rating standard permit vehicles in enveloping the effects of overweight vehicles in the State of Rhode Island and to recommend changes if necessary. A detailed analysis of an overweight permit vehicle database for non-divisible single trips obtained from Rhode Island Departments of Motor Vehicles (RIDMV) and Transportation (RIDOT) is performed. The data are analyzed to characterize vehicle configurations (i.e. number of axles, axle spacing, axle weights), permit handling (i.e. reviewing agency, length of time to process a permit, number of submittals), load effects (i.e. maximum shear and bending moments for multiple bridge spans). A comparison is also made between RIDMV-approved permits and RIDOT-approved permits in an effort to characterize the criteria used by each agency for review. To achieve the goal, the research plan will collect representative oversize/overweight permit records from the electronic database currently maintained by, develop statistical descriptors for overweight permit vehicles in Rhode Island, evaluate truck load effects (i.e. positive and negative bending moments and shear forces) for simple and two-span continuous bridges of varying span lengths, and identify vehicle configurations that best envelope the effects of these overweight permit vehicles. This study will provide a realistic assessment of the impact of overweight permit vehicles on highway bridges across the State. This information is critically important to their continued efforts of ensuring the safety of bridges in the State. Based on the results of this study, the Department of Transportation may or may not elect to make adjustments to the current load rating standard permit vehicle or their permit review process. The study shows that a data quality check should be set up at the onset of the permit application process to get error-free, valid truck information from the database. There is also a need to establish a set of guidelines to be followed to forward the permit applications of overweight trucks to RIDOT for detailed and in-depth review. The 3- and 4-axle permit trucks were found to be the critical trucks in terms of load effects on the bridges with the effect being more severe in the case of short-span bridges.

Subject Area

Civil engineering

Recommended Citation

Sarju Mulmi, "Analysis of permit vehicles in Rhode Island" (2011). Dissertations and Master's Theses (Campus Access). Paper AAI1497505.