FEDERAL HIGHWAY ADMINISTRATION Performance Based Practical Design September 7, 2016 Robert Mooney WHAT IS PBPD? PBPD is a decision making approach that helps agencies better manage transportation investments and serve system-level needs and performance priorities with limited resources. PRACTICAL DESIGN EXAMPLE PRACTICAL DESIGN EXAMPLE PBPD IS NOT: New Policy, Regulation, or Requirement Opportunity to disregard long-term needs: For short term cost savings Overlooking future development Compromising on safety, user needs (bike, ped, etc.), or accommodation of freight to save money PRACTICAL DESIGN, aka Flexible Design Open Roads Practical Solutions
Practical Engineering Practical Performance Based Improvements Practical Design Common Sense Engineering PBPD OVERVIEWS WA ME MT ND VT MN NH OR ID NY WI SD
MI WY PA IA NE NV IL UT IN MO DE DC WV KS RI NJ MD OH CO
CA MA CT VA KY NC TN AZ OK NM SC AR MS AK AL GA TX LA FL VI
HI 18 Executive Overviews Delivered PR 2 Executive Overviews Planned PBPD WORKSHOPS WA ME MT ND VT MN NH OR ID NY WI SD MI WY
PA IA NE NV IL UT MD OH IN KS MO RI NJ DE DC WV CO CA
MA CT VA KY NC TN AZ OK NM SC AR MS AK AL GA TX LA FL HI 13 Workshops Delivered PR
VI COMMON THEMES OF PBPD: Project decisions are based on critical examination of geometric elements Select/size elements that serve priority needs Reduce or eliminate those that dont Choices made to serve project priorities while trying to save money Project savings benefit System Needs NOTABLE ATTRIBUTES PBPD focuses on performance improvements that benefit both project and system needs. Agencies make sound decisions based upon performance analysis. By scrutinizing each element of a projects scope relative to value, need, and urgency, a PBPD approach seeks a greater return on infrastructure investments. Ass Mg et mt. D OVERLAPPING PBPD P B P xt e
t n Co sitive s n Se ution l So Context Sensitive Solutions Valu e Eng inee ring Value Engineering System Performance Practical Design Savings Item Original Cost Practical Cost Savings Pavement Design Reduce driving lane from 12' to 11'
$3,600,000 $3,300,000 $300,000 $120,000 $60,000 $60,000 Reducing shoulder Aggregate width 4' to 1' $160,000 $40,000 $120,000 Reduce to 3:1 Side Slopes and V-bottom ditches $775,000 $525,000 $250,000 $3,000,000 $500,000 $2,500,000
$232,000 $500,000 $132,000 $400,000 $100,000 $100,000 Reduce number of mitigated trees $50,000 $10,000 $40,000 Modify instead of replace most large structures Structure Removal Minimizing Cover Depth at Crest Curves $700,000 $120,000 $200,000 $20,000 $500,000 $100,000 $40,000 Structure Backfill $60,000
$20,000 $40,000 Minimize Underdrain Depth and locations Shoulder Design Utilities Relocate 8" gas line to lower elevation Move OH utilities inside Clear Zone: Reduce trees to be removed Reduce area of mitigated wetlands Structures TOTAL PROJECT SAVINGS: $4,150,000 PERFORMANCE BASED PRACTICAL DESIGN EXAMPLE PERFORMANCE BASED PRACTICAL DESIGN EXAMPLE 12 feet Alternative A 12 feet Alternative
B 12 feet Shoulder Width 1 foot 5 feet 8 feet Construction Costs 2016-2036 Expected Total # of Crashes % Reduction of Crashes over Existing Conditions Benefit -Cost Ratio $0 $16.5 mil $26.3 mil 636 532 504 N/A 17%
21% N/A 2.3 1.9 Roadway Element Existing SR 264 Lane Width PERFORMANCE BASED PRACTICAL DESIGN EXAMPLE Highway 10 2013 AADT (vehicles per day) Severity Number Percent 1. Ramsey West 33,500 Fatal
13 0.8% 2. Armstrong Boulevard 33,500 Incapacitating Injury 29 1.8% Non-Incapacitating Injury 135 8.3% Possible Injury 324 20.0% No Injury (PDO) 1,120 69.1% Total
1,621 100.0% 3. Ramsey Boulevard 38,500-44,000 4. Sunfish Lake Boulevard 44,000-47,500 5. Anoka 47,500-60,000 PERFORMANCE BASED PRACTICAL DESIGN EXAMPLE Groups Analyzed Estimated # of Crashes Reduced Percent Benefit of Freeway Alternative 1
136 19% 1-2 428 60% 1-3 494 70% 1-4 623 88% 1-5 663 94% 1-6 683 96%
ALL ENGINEERING CHOICES HAVE TRADE-OFFS Which One Would You Choose? nB o i t Op Same Value, A n io Lower Cost Opt Cost Meets or Exceeds Design Criteria Same Cost, Better Value Minimum Standards (Operations, Safety, Efficiency etc.) Value Below Design Criteria
17 INTERACTIVE EXERCISE: EXPANDING FREEWAY CAPACITY Estimated Crash Statistics Estimated average crash freq. during Study Given the same Period, crashes/yr: No Build Outside Shoulder Width Add lane by reconfiguring widths traffic volume, which of these three Total K A B C PDO options will the HSM predict: 293.6 0.8 2.3 16.8 63.4 210.1 1. Fewest total crashes?
293.9 1.3 3.1 22.9 65.3 201.3 2. Fewest fatalities? Construct new lane(s) and shoulders 254.4 0.9 2.6 18.6 54.2 178.1 Can we make more out of our alternatives? Can we have the best of both? Estimated Crash Statistics Estimated average crash freq. during Study Period, crashes/yr: Total
K A B C PDO 293.6 0.8 2.3 16.8 63.4 210.1 293.9 1.3 3.1 22.9 65.3 201.3 254.4 0.9
2.6 18.6 54.2 178.1 Outside Shoulder Width 12 4 12 11 12 11 12 12 12 12 12 12 12
12 10 12 12 19 OPERATIONAL BENEFITS OF SHOULDER RUNNING Before After 20 SHOULDER USE AND LIMITATIONS OF THE HSM CMF's for Freeways 1.53 1.55 Inside Shoulder Width Lane Width Outside Shouder Width Crash Modification Factor
1.45 1.33 1.35 1.25 1.15 1.15 1.05 1.00 0.95 0.87 0.85 0.75 0.75 2 3 4 5 6 7 8 9 10
11 12 13 14 15 Width of Feature (Ft) 21 KEY REPORTS CONTROLLING CRITERIA Effective May 5, 2016 -- Controlling Criteria for NHS Low Speed Roadways (Design Speed < 50 mph): Design Speed 50 mph: 1. Design Speed 1. Design Speed 2. Design Loading Structural Capacity 2. Lane Width 3. Shoulder Width 4. Horizontal Curve Radius 5. Superelevation 6. Stopping Sight Distance 7. Maximum Grade 8. Cross Slope 9. Vertical Clearance 10. Design Loading Structural Capacity
WWW.REGULATIONS.GOV The new policy eliminated: Bridge Width Vertical Alignment Lateral Offset to Obstruction And renamed: Horizontal Alignment Horizontal Curve Radius Grade Maximum Grade Structural Capacity Design Loading Structural Capacity FHWA WILL BE A GOOD PARTNER FHWA is prepared to support States as they develop projects with a system performance mindset using data-driven methods WWW.FHWA.DOT.GOV/DESIGN/PBPD/ ROBERT MOONEY 202-366-2221 [email protected] GEORGE MERRITT 404-562-3911 [email protected]
