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10 quantitative guidelines may be beneficial while the other indi- the variations noted in maintenance criteria and maintenance cated only if sufficient resources were available to comply with assessment criteria warrant further investigation. the more quantitative guidelines. The second agency expressed Third, failure to promptly repair a damaged barrier may concern about the increased liability the agency would incur if increase a transportation agencies legal liability. Crashes involv- unable to comply completely with the quantitative guidelines. ing vehicles impacting previously damaged barriers are found to occur in the field. A review of the available tort liability cases in the U.S. revealed that impacts into previously damaged bar- 2.4 Discussion riers have occurred and have been litigated (Keller v. State A review of the available literature and a survey of U.S. of Illinois, 1982; Leonard Paxton v. Department of Highways, and Canadian transportation agencies support several impor- 1999; McDonald v. State of New York, 2002; Rosemary F. tant notions regarding the current longitudinal barrier repair Woody v. Department of Highways, 1989; Volpe v. State of New practices and priorities amongst transportation agencies. First York, 2000). Many of these cases, such as McDonald v. State of is the general lack of quantitative guidelines to assess the longi- New York, were dismissed. However, it would seem advanta- tudinal barrier damage level and the associated need for repair. geous, at least from a legal perspective, to have more quantita- Combining the literature review and survey results, data tive guidelines for when to repair damaged barrier and pri- was obtained from a total of 40 of 50 U.S. states and 8 of 10 oritize damaged barrier sections. Interestingly, the survey Canadian Provinces (approximately 80 percent of the U.S. respondents could provide almost no documented cases of and Canadian transportation agencies). Only 13 States and vehicles impacting previously damaged barriers. 2 Canadian Provinces, less than one-third of the 48 transporta- All of these notions seem to point to the need for a better tion agencies, had either quantitative barrier repair criteria or understanding of the effects of barrier damage on barrier quantitative maintenance assessment guidelines for longitu- performance. dinal barrier. For the remaining two-thirds of agencies, bar- rier repair and barrier assessment criteria usually required a 2.5 Conclusions determination of whether the barrier was "functional," with no specific guidelines for making that assessment. The cur- Based on the findings of the literature review and analysis rent FHWA guidelines, published in 2008, do provide some of the survey responses, the following conclusions are drawn: loosely quantitative guidelines for barrier repair; however, the guidelines appear to be founded on engineering judgment in- 1. A majority of the current U.S. and Canadian transportation stead of a strong analytic foundation. In addition, the survey agency guidelines for longitudinal barrier repair lack quan- responses suggest that transportation agencies would see a titative measures to evaluate the need for barrier repair. In benefit in more quantitative barrier repair guidelines. most of these cases, the practice is to repair barriers if it is Second is the apparent variation between barrier assessment "non-functional" with no specific guidance on making that criteria, as present in maintenance assessment procedures, and assessment. those criteria used to determine the need for barrier repair, as 2. There is a need for the development of more quantitative prescribed in the maintenance manual. For thirteen agen- guidelines for longitudinal barrier repair that are based on cies, information from both maintenance assessment proce- a strong analytical foundation. This analytical foundation dures and corresponding agency maintenance manuals was should include full-scale crash testing of damaged barrier, available. Six agencies (Indiana, Iowa, Montana, Pennsylvania, pendulum testing of damaged barrier sections, and finite Florida, and Washington State) had quantitative maintenance element modeling of damaged barrier impacts. assessment criteria but lacked quantitative barrier repair crite- 3. Several state transportation agencies, including California, ria in the maintenance manual. Two agencies (California and Iowa, Montana, Ohio, Washington State, North Carolina, North Carolina) had quantitative barrier repair criteria in the Pennsylvania, Missouri, and Wisconsin, were found to maintenance manual but lacked quantitative barrier assess- have quantitative measures to rate or provide guidance on ment criteria. Ohio was the only agency that had both quan- the repair of flexible and semi-rigid barriers. Even in these titative barrier repair criteria and quantitative maintenance cases, however, there appears to be little connection between assessment criteria while the remaining four agencies (Texas, the criteria used to evaluate the condition of longitudinal Tennessee, Virginia, and Kansas) had neither quantitative bar- barriers for the purpose of maintenance assessment and rier repair nor quantitative maintenance assessment criteria. the criteria used by maintenance personnel to determine Although these criteria are not required to coincide, all of the the need for barrier repair. As both criteria are based heav- maintenance assessment criteria found in this study were either ily on barrier functionality, these variations warrant fur- largely or solely based on barrier functionality. At a minimum, ther investigation.