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From page 116... ... 116 CHAPTER 8 Pilot Testing and Analysis on SHRP 2 C11 Product 8.1 Introduction Most benefit–cost analysis tools incorporate recurring congestion impacts and exclude nonrecurring (resulting from incident/weather/work zone/demand fluctuation) congestion impacts. Read the entire page →
From page 117... ... 117 Figure 8.1. Map of test site, I-5 through JBLM. Read the entire page →
From page 118... ... 118 Figure 8.2. INRIX congestion scan of I-5 JBLM area. Read the entire page →
From page 119... ... 119 interface (Figure 8.3) Read the entire page →
From page 120... ... 120 Figure 8.4. Base year (2012) Read the entire page →
From page 121... ... 121 S c e n a ri o C o n g e s ti o n M e tr ic s S R 5 1 0 t o B ro w n F a rm R d B ro w n F a rm R d to M o u n ts R d M o u n ts R d t o C e n te r D r C e n te r D r to D u p o n tS te il a c o o o m R d D u p o n tS te il a c o o m R d t o 4 1 s t D iv is io n D r 4 1 s t D iv is io n D r to B e rk e le y S t B e rk e le y S t to T h o rn e L a n e T h o rn e L a n e t o G ra v e ll y L a k e D r G ra v e ll y L a k e D r to B ri d g e p o rt W a y B ri d g e p o rt W a y to S R 5 1 2 2 0 1 2 B a s e C a s e Overall mean TTI 1.12 1.10 1.21 1.22 1.16 1.37 1.56 1.18 1.17 1.18 TTI95 1.37 1.34 1.66 1.67 1.51 1.99 2.39 1.53 1.51 1.51 TTI80 1.16 1.13 1.31 1.32 1.23 1.56 1.85 1.27 1.26 1.26 TTI50 1.07 1.05 1.15 1.15 1.10 1.29 1.48 1.14 1.13 1.13 % trips less than 45 mph 13.9% 13.3% 24.0% 24.5% 19.3% 32.6% 41.9% 18.4% 17.6% 17.7% % trips less than 30 mph 2.3% 1.4% 4.5% 4.6% 2.7% 12.8% 23.1% 5.7% 5.5% 5.5% Overall mean TTI 1.07 1.08 1.13 1.13 1.10 1.04 1.06 1.10 1.10 1.10 TTI95 1.25 1.29 1.42 1.43 1.34 1.14 1.21 1.32 1.31 1.31 TTI80 1.10 1.11 1.18 1.18 1.13 1.05 1.08 1.14 1.13 1.13 TTI50 1.04 1.04 1.07 1.08 1.05 1.02 1.03 1.06 1.06 1.06 % trips less than 45 mph 9.7% 11.3% 16.3% 16.5% 13.3% 5.4% 8.1% 12.2% 11.8% 12.0% % trips less than 30 mph 1.2% 1.2% 1.8% 1.8% 1.4% 0.8% 1.0% 1.8% 1.7% 1.7% Overall mean TTI 1.37 1.64 1.87 1.65 1.64 1.77 2.06 1.35 1.33 1.34 TTI95 1.99 2.58 3.06 2.60 2.58 2.86 3.42 1.96 1.92 1.93 TTI80 1.56 1.98 2.33 1.99 1.97 2.18 2.60 1.53 1.51 1.51 TTI50 1.29 1.55 1.77 1.56 1.55 1.68 1.94 1.28 1.26 1.27 % trips less than 45 mph 32.6% 47.6% 58.6% 48.0% 47.6% 54.1% 67.1% 31.9% 30.5% 30.9% % trips less than 30 mph 12.7% 24.8% 33.5% 25.0% 24.8% 29.7% 37.0% 12.9% 12.5% 12.6% Overall mean TTI 1.19 1.58 1.68 1.57 1.56 1.18 1.11 1.22 1.17 1.18 TTI95 1.60 2.44 2.68 2.42 2.39 1.52 1.36 1.64 1.54 1.56 TTI80 1.28 1.89 2.04 1.88 1.85 1.27 1.14 1.32 1.25 1.25 TTI50 1.13 1.49 1.59 1.49 1.48 1.13 1.06 1.16 1.11 1.12 % trips less than 45 mph 22.2% 43.4% 50.1% 43.0% 41.9% 18.2% 13.9% 22.9% 20.3% 20.8% % trips less than 30 mph 3.7% 23.4% 25.9% 23.3% 23.0% 5.6% 1.5% 5.9% 3.0% 3.1% 2 0 1 2 B a s e C a s e 2 0 1 2 S c e n a ri o 1 2 0 3 2 B a s e C a s e 2 0 3 2 S c e n a ri o 1 Figure 8.5. Corridor performance indicators. Read the entire page →
From page 122... ... 122 Figure 8.6. Estimates of annual travel delay. Read the entire page →
From page 123... ... 123 8.6 Cost of Alternatives To perform economic analyses and compare project alternatives, it is necessary to estimate both benefits and costs of alternatives. The travel time reliability tool helps estimate travel time and reliability benefits. Read the entire page →
From page 124... ... 124 Figure 8.8. Main menu of the PLCE tool. Read the entire page →
From page 125... ... 125 A summary of the benefit–cost analysis is shown in Figure 8.10. The analysis was performed with a set of assumptions that include the following:  An analysis period of 20 years;  Annual discount rate of 4% (used to convert future costs and benefits to present values) Read the entire page →
From page 126... ... 126 Figure 8.10. Summary of benefit–cost analysis. Read the entire page →
From page 127... ... 127 analytic tools (Figure 8.11) Read the entire page →
From page 128... ... 128 Note that the reliability tool provides an overall TTI for both direction of travel instead of providing separate indices for each direction. Figure 8.12. Read the entire page →
From page 129... ... 129 Figure 8.13. TTI values for 2012 base case using congested capacity. Read the entire page →
From page 130... ... 130 recurring delay as well as improving travel time reliability. Most of the existing economic analysis tools consider only recurring delay while excluding the effects of travel time reliability. Read the entire page →
From page 131... ... 131 depending on type of estimate (e.g., conservative or liberal) Read the entire page →

From page 116...

... 116 CHAPTER 8 Pilot Testing and Analysis on SHRP 2 C11 Product 8.1 Introduction Most benefit–cost analysis tools incorporate recurring congestion impacts and exclude nonrecurring (resulting from incident/weather/work zone/demand fluctuation) congestion impacts.