Skip to main content

Median Cross-Section Design for Rural Divided Highways (2014) / Chapter Skim
Currently Skimming:


Pages 103-106

The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.


From page 103...
... 103 C H A P T E R 6 This chapter discuss the interpretation of the analysis results presented in Chapters 4 and 5 of the report and pre­ sents design guidelines based on those results. 6.1 Median Width In assessing median width effects from the crash analysis for rural divided highways, the results for rural four­lane free­ ways are of primary interest, because the smaller sample sizes for four­lane divided nonfreeways and six­lane freeways were too small to provide useful or consistent results.
Read the entire page →
From page 104...
... 104 positive effect on safety. This effect is cost­effective, even though earthwork/grading costs increase.
Read the entire page →
From page 105...
... 105 cost analysis results. The analysis results show that flexible barriers (i.e., cables)
Read the entire page →
From page 106...
... 106 Crash type Crash modification factor Flexible median barriers Semi-rigid median barriers Rigid median barriers Total medianrelated crashes F & I medianrelated crashes Total medianrelated crashes F & I medianrelated crashes Total medianrelated crashes F & I medianrelated crashes Rural four-lane freeways All median-related crash types combined 3.27 1.60 2.52 1.50 2.40 1.08 CMCs 0.04 0.08 0.02 0.00 0.00 0.00 CMCs + NCMCs 0.45 0.38 0.11 0.17 0.00 0.00 Rollover crashes 0.26 0.43 0.12 0.31 0.00 0.00 Hit-fixed-object crashesa 8.20 2.32 5.26 2.13 9.92 1.23 Other median-related crashes 2.28 1.67 1.72 1.47 1.40 0.86 Rural six-lane freeways All median-related crash types combined 1.66 1.17 –– –– –– –– CMCs 0.27 69.00 –– –– –– –– CMCs + NCMCs 0.26 69.00 –– –– –– –– Rollover crashes 0.77 31.00 –– –– –– –– Hit-fixed-object crashesa 3.09 1.28 –– –– –– –– Other median-related crashes 0.84 14.00 –– –– –– –– a Increases in crash frequency include hit-barrier crashes. Note: Statistical significance and standard errors are shown in Tables 4-30 and 4-31.
Read the entire page →

Key Terms



This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More information on Chapter Skim is available.