Comprehensive Truck Size and Weight Limits Study: Stakeholder Sessions 2013-2015: Feedback and Comments, Final Report

4. SUMMARY OF THEMES AND TRENDS

4.1 Significant Comments Affecting Content & Design of the Study

As presented in this section of the report on stakeholder input, "significant comments" were those that, in the context of this CTSWL Study either: 1) potentially changed the technical approach in the project plan, or 2) added resources to the Desk Scan. These comments and associated responses were generated by the breakout sessions and web discussions held on May 29, 2013, and follow by topic area. The comments include their disposition with respect to the Study.

Data, Modeling and Methodology:

"Look at GAO 11-134—A Comparison of the Costs of Road, Rail, and Waterways Freight Shipments That Are Not Passed on to Consumers." – The study was included in the Desk Scan phase of the project.
"Build in behavioral factors in modal choice analysis – do not assume a strict cost-based choice basis." – No generally accepted method was available to include this aspect of modal shift analysis.
"Virginia did a freight study a few years ago that we should look at." – The Virginia Study was included in the Desk Scan phase of the project.

Safety:

"Perhaps, there could be an endorsement process for new weight and limits and configurations that would create a system of checks and balances." – The comment is considered out of scope for the Study as it is not within the scope outlined by Congress.
"The study should look at how heavier and oversized trucks interact with roadway safety infrastructure (guard rails, etc.)." – This assessment was attempted but tools available to assess median barrier and guard rail adequacy to accommodate impact from heavier trucks is currently not available. A recommendation that currently available tools be updated to evaluate heavier truck impacts is included as a recommendation in the Study findings.
"If weight increases it may overwhelm driver protection, and increase collision severity." – Severity of truck crashes was assessed in the Study.
"The team should evaluate safety on a ton-mile basis since trucks might carry 20% more cargo. This is how rail safety is evaluated." – Crash rates are based on travelled miles, not ton-miles. The Study used truck vehicle miles traveled (VMT) to evaluate crash rates due to data availability limitations.
"Societal costs of crashes should be included in the study." – There is no uniform, generally accepted approach for completing such an assessment.
"ATRI recently completed a study on large truck safety trends that should be considered." – ATRI’s Study was included in the Desk Scan phase of the project and was considered.
"FMCSA-sponsored "Cost Benefit Analysis of Onboard Safety Systems" breaks out the real-world, line item costs of crashes by truck type, severity, and commodity-involvement." – This work was evaluated as part of the Desk Scan phase of the Study.
"It’s been a long time since the last DOT sponsored "Technology Scan" of Europe and Scandinavia but both places have vast amounts of safety info and wisdom and folks who may well be willing to share it. Specific to TSW [truck size and weight], there has been much in recent good work accomplished – hope you can include it in the American study." – European and Scandinavian information was included in the Desk Scan phase of the Study.
"How will Study address previous studies, like the Vermont study?" – Previously completed work such as that referred to was included in the Desk Scan phase of the Study.
"Reviewing findings of previous studies may help in assessing the vehicles to examine in this Study." – The Desk Scan phase of the Study was helpful in doing so.
"Western Governors Association study included many aspects of what will be covered in the current TSW Study." – The referenced Study was included in the Desk Scan phase of the Study.
"Longer Combination Vehicles (LCVs) don’t always operate under perfect conditions. Consider operations in inclement weather, in mountainous terrain, in dense urban areas." – The LCVs evaluated in the Study were analyzed under a variety of weather conditions and terrain type environments.

Bridge Impacts:

"In South Carolina Department Of Transportation (SCDOT) we did fatigue analysis for four archetype bridges." – The South Carolina Study was included in the Desk Scan phase of the Study.
"The sample should be based on the corresponding percentages of different types of structures on the Interstate." – The sampling framework applied in the structural analysis was constructed in agreement with the recommendation.
"Really should look at the process that NCHRP 12-78 used to make a sample set of bridge models that was reflective of the real-life bridges found in the NBI."- The referenced National Cooperative Highway Research Program Study was included in the Desk Scan and considered as the sample framework was conducted.
"Idaho Department Of Transportation (Idaho DOT) did a bridge analysis in conjunction with an LCV pilot program." – The work completed by Idaho DOT was included in the Desk Scan phase of the project.

Dynamic Performance:

"Truckingvideo.com/SafetyTruck has an online video that covers stability of trucks and considers the effects of uneven loads." – The video was accessed and evaluated by the safety Project Team but not included as a reference in the Desk Scan.

Driver Certification:

"Driver experience is important. Current operations pick experienced drivers. If use became widespread it would bring in less-experienced and brand new drivers to operate the larger equipment." – The consideration of driver age was made in various areas of the Crash/Safety Study area.
"FMCSA has driver data/scorecards." – Noted by the Study team.
"The team should look at the results of a FMCSA recent listening session on new entrant standards. The quality of drivers and the details on driver regulations have large impacts on safety." – Noted by the Study team.
"LCV operators should be certified." – The requirements for graduated licenses for LCV operations were not considered as in-scope for the Study and therefore not evaluated.

Economic and Environmental Impacts:

"Include fuel usage for full as well as empty trucks." – This suggestion was reflected in the analysis of fuel consumption impacts included in the Study as it relates to the economic and environmental elements of the Modal Shift analysis.

Braking:

"Longer, heavier (10/11 axle Rocky Mountain Doubles" have twice as many brakes for only 60 percent more weight. They corner and stop better than 80,000 lb. 5-axle trucks." – Rocky mountain doubles were considered but not included in the Study due to the preference stakeholders identified for other alternative configurations.

Performance-based Standards:

"Consider configuration’s handling, stability characteristics as well as its low-speed offtracking." – This work was performed as part of the vehicle stability and control assessments in the Crash/Safety area of the Study.
"Focusing only on dimensions/lengths instead of focusing on the configuration’s operational performance characteristics limits design possibilities." – Noted.

Truck Maintenance Costs:

"Maintenance costs increase as truck weights increase." – This point was examined in the Desk Scan phase of the project.
"More frequent inspections of truck frames, floors, and other load-bearing components." –This comment was not considered as within the scope of the Study as outlined by Congress.

Note: Public comments from Stakeholder Events #2, #3 and #4 did not substantially alter the design of the Study as they were either previously addressed above or came in after the Study work had progressed past the point of modification.

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