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NORTH DAKOTA DEPARTMENT OF TRANS. Pavement Preservation. A strategic approach to managing transportation infrastructure. NORTH DAKOTA DEPARTMENT OF TRANS. Pavement Preservation. NDDOT Mission/Goals Background/Need Reasons Highway Investment Strategies Design Guidelines
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NORTH DAKOTA DEPARTMENT OF TRANS. Pavement Preservation A strategic approach to managing transportation infrastructure New Design Guidelines
NORTH DAKOTA DEPARTMENT OF TRANS. Pavement Preservation • NDDOT Mission/Goals • Background/Need • Reasons • Highway Investment Strategies • Design Guidelines • Statewide Safety Program New Design Guidelines
NDDOT MISSION/GOALS • NDDOT MISSION • Provide a transportation system that safely moves people and goods. • GOALS • Enhance customer satisfaction • Increase safety on North Dakota’s transportation system and within the Department of transportation. • Improve the quality and efficiency of North Dakota’s transportation system and services. • Enhance employee effectiveness and well-being. • Strengthen stakeholder relationships. New Design Guidelines
Background/Need • 8411 centerline miles of roadway • 70% of the vehicle miles traveled • Interstate • Interregional system • 14.2% of the vehicle miles traveled • State Corridor system New Design Guidelines
Background/Need • From 1989 to 2000, 2400 miles of the low load system has only received routine maintenance • A number of these roads are still in fair condition • Inadequate funding for major rehab or reconstruction of 2400 miles of roadway. New Design Guidelines
Background/Need • Survey said: • Improve ride • Improve load carrying capacity • 2006 PMS data • 33% of the highway system is deficient in ride, distress or load carrying capacity. New Design Guidelines
Background/Need • The Right Treatment – • Apply correct treatment to extend the service life of the roadway • Improve performance and safety • To The Right Road – • PMS identify, • DE’s confirm • At The Right Time – • Before there is significant pavement damage. New Design Guidelines
NDDOT Highway Program + + @#!% Rules New Design Guidelines
Highway Performance Classification System New Design Guidelines
HPCS Concepts • 5 Systems with various levels of performance in areas of: • Ride & Distress • Load Capacity • Access • Allowable Work Types New Design Guidelines
HPCS Categories • Interstate • Ride & Distress – Strive for an excellent Ride • Load Capacity – no load restrictions • Access – Controlled access • Allowable Work Types – all types of construction are typically allowed New Design Guidelines
HPCS Categories • Inter-regional System • Similar performance as interstate except for controlled access • Ride & Distress – Strive to maintain an excellent Ride • Load Capacity – Legal Weight (Year round) • Access – Sections may have partially controlled access • Allowable Work Types – all types of construction are typically allowed New Design Guidelines
HPCS Categories • State Corridor • Ride & Distress – Strive to maintain a good to excellent • Load Capacity – No Load Restrictions • Access – no type of control is targeted • On as needed basis for safety • Shoulder type – gravel except for higher volume NHS segments • Allowable Work Types – all types of construction are typically allowed New Design Guidelines
HPCS Notes • Interstate, Inter-regional & State Corridors • Have 52% of mileage • Carry 84% of VMT • Carry 84% of Truck VMT • Carry 89% of the ESAL VMT New Design Guidelines
HPCS Categories • District Corridors • Ride & Distress – Strive to maintain a Good Ride • Load Restriction– 8 Ton for NHS, 7 Ton (Spring ONLY) Non-NHS • Access – No access control level is targeted • Shoulder Type – gravel except for higher volume NHS routes • Allowable Work Types – primarily preventive maintenance or surface rehabilitation. New Design Guidelines
HPCS Categories • District Collector • Ride & Distress – Strive to maintain a good Ride • Load Restriction – 7 Ton or 6 Ton (Spring ONLY) • Access – No access control level is targeted • Shoulder Type - gravel • Allowable Work Types – primarily preventive maintenance or surface rehabilitation. • Note: These routes carry 2.5% of the ESAL VMT & 4.1% of VMT New Design Guidelines
HPCSLegislative Backlog/Cost Analysis ComponentEstimated Cost Pavements Ride $218 Million Distress $ 31.9 Million Load $138.8 Million Geometrics Shoulder Widen $214.4 Million Widening for Overlays $ 22.7 Million Vertical Clearance Interstate $ 9.9 Million Non-Interstate $ 22.0 Million New Design Guidelines
NDDOT Highway Program + + @#!% Rules New Design Guidelines
Investment Strategy • Implemented in 1999, Revised 2007 • Intent of Program • Change Prioritizing of Projects from Worst-First to a prioritization of candidates by Work-Type • Create a Balanced Program by Work Type • Create an optimal investment strategy New Design Guidelines
Investment Strategy • Optimal Funding • Interstate System 45.0% • Interregional System 20.0% • State Corridor System 12.5% • District Corridor System 17.5% • District Collector System 5.0% New Design Guidelines
Investment Strategy • Investment categories • Interstate System • Interregional System • State Corridor, District Corridor, District Collector Systems New Design Guidelines
Investment Strategy Cont’d. New Design Guidelines
Types of Work • PREVENTIVE MAINTENANCE • The purpose of the Preventive Maintenance program is to protect the pavement structure, slow the rate of pavement deterioration and/or correct pavement surface deficiencies. Surface treatments used for preventive maintenance are targeted at pavement surface defects primarily caused by the environment and by the daily wear and tear of traffic. Structural deficiencies caused by traffic loading are not corrected by using these treatments. New Design Guidelines
Types of Work • Examples of Preventive Maintenance treatments are: • Crack Pouring, • Route and Seal, • Seal Coats, • Micro-Surfacing, • Asphalt Overlay 2” Max, • Repair of depressed cracks, • Minor CPR (< 10% pavement surface area per mile), • DBR • Diamond Grinding, • Pavement Marking, • Painting Structures, etc. New Design Guidelines
Types of Work • MINOR REHABILITATION • A planned strategy to extend the useful life of a highway by restoring the pavement structure without necessarily improving existing geometrics. The minor rehabilitation of roadways will use repair techniques designed to repair pavement distress areas primarily caused by the environment and by the daily wear and tear of traffic. A minor rehabilitation strategy will restore the load carrying capacity to its original condition. New Design Guidelines
Types of Work • Examples of Minor Rehabilitation treatments are: • Asphalt Overlay, • Distress Area Repairs and Asphalt Overlay • Mill & Overlay, • CIR, • Minor sliver grading to correct inslope • Bridge Approach Repair, • Bridge Rail Repair, • Deck Overlay, • Guardrail, etc. New Design Guidelines
Types of Work • STRUCTURAL IMPROVEMENTS • A planned strategy to extend the useful life of a highway by restoring the pavement structure without necessarily improving existing geometrics. A structural improvement will increase the load carrying capacity to meet the HPCS guidelines. New Design Guidelines
Types of Work • Examples of Structural Improvement treatments are: • Asphalt Overlay in excess of 3”, • White topping New Design Guidelines
Types of Work • MAJOR REHABILITATION • A planned strategy in which major work is performed to bring a highway up to an acceptable condition to extend the service life and provide operational improvements (i.e. adding turn lanes). New Design Guidelines
Types of Work • Examples of Major Rehabilitation treatments are: • Mine and Blend and HBP • Full Depth Reclamation (FDR) • Major Concrete Pavement Repair • (> 10% of the surface area per mile) • Crack and Seat and HBP New Design Guidelines
Types of Work • NEW/RECONSTRUCTION • Defined as a planned strategy in which a new road is constructed. This work may include work items such as relocating an existing route on new alignment, or completely removing the old pavement structure and restoring the roadbed and surfacing, or major widening on an existing roadway to increase traffic capacity (excludes realigning horizontal curves). New Design Guidelines
@#!% Rules NDDOT Highway Program + + New Design Guidelines
Design Guidelines Signed by NDDOT and FHWA the week of March 19, 2007. New Design Guidelines
Design Guidelines • Cover • Design Guidelines • Implementation plan • Statewide Safety Program • Implementation plan New Design Guidelines
Design Guidelines • Guidelines shown are recommended minimums, evaluate each project. • Not to reduce widths • District Corridor on NHS design to State Corridor • Forecast Traffic volumes + 10% New Design Guidelines
Design Guidelines • Design Guidelines common to Preventive Maintenance, Minor Rehab: • Use current ADT • Maintain existing • Super elevation • Driving Lane Cross slope • Horizontal Curvature • Vertical Curvature • Safety issues are part of Statewide Safety Program unless there is an identified need. • Roadway Width, Use appropriate width to meet NDDOT guidelines. New Design Guidelines
Design Guidelines • Design Guidelines common to Preventive Maintenance, Minor Rehab (Continue): • ADA improvement will be considered and included in the Environmental Document • Signage • Should meet MUTCD if engineering judgment indicates • One compliant device could cause driver confusion • Replacement of whole series can be achieved • Use posted speed limit New Design Guidelines
Design Guidelines • Minor Rehabilitation: • Inslope, If proposed inslope is < 3:1 consider cost effective treatment. In fill sections where the inslope breaks to < 3:1 outside the clear zone a 4:1 inslope should be used in the clear zone. • Safety items, Safety hardware < NCHRP 230 standards upgrade to NCHRP 350 standards. New Design Guidelines
Design Guidelines • Structural Improvement: • ADT 20 year projection • Super elevation – Attempt to correct if cost effective • Driving Lane Cross slopes: • HBP over Asphalt 2.1% • HBP over concrete 1.5% - 2.5% • Horizontal curve: Sign deficient • Vertical curve: existing • Clear Zone: 20’ New Design Guidelines
Design Guidelines • Structural Improvement (continue): • Roadway Shoulder Cross slopes: • HBP over Asphalt 8.0% Max. • HBP over concrete, Non- Interstate 8.0% Max • HBP over concrete, Interstate 6.0% Max • Safety items, Safety hardware < NCHRP 230 standards upgrade to NCHRP 350 standards. • Replace Mailbox supports • ADA improvement will be considered and included in the Environmental Document • Regulatory and warning signs and pavement markings to MUTCD New Design Guidelines
Design Guidelines • Major Rehabilitation: • ADT 20 year projection • Super elevations, Correct to NDDOT standards. • Use posted speed limit • Cross Slope, Driving lanes 1.5% - 2.5%, Shoulder 6% max. New Design Guidelines
Design Guidelines • Major Rehabilitation (continued): • Horizontal Curvature, Use existing, sign when less than posted speed. On State and Interregional Corridors with ADT >750, if existing horizontal curvature is designed for less than 15 mph less than the posted speed make cost effective improvement or sign accordingly. New Design Guidelines
Design Guidelines • Major Rehabilitation (continued): • Interregional System: • Vertical Curvature, Maintain existing except when ADT > 2000 then use stopping sight distance for crests and comfort for sag curves. Decision sight distance should be considered in areas where complex driver decisions are required such as intersections, overhead grade separations, lane drops or additions, etc. Passing areas should be provided at reasonable intervals based on terrain and traffic volumes. A rule of thumb would be a passing area every 3- 5 when the ADT < 2000 and every 3 miles when the ADT > 2000. New Design Guidelines
Design Guidelines • Major Rehabilitation (continued): • State Corridor, District Corridor and Collector • Vertical Curvature, ADT < 2000, existing vertical curves should meet a design speed of no less than 20 mph below the overall project design speed. ADT > 2000 then use stopping sight distance for crest curve design and comfort curve design for sag curves. Passing areas should be provided at reasonable intervals based on terrain and traffic volumes. A rule of thumb would be a passing area every 3- 5 when the ADT < 2000 and every 3 miles when the ADT > 2000. New Design Guidelines
Design Guidelines • Major Rehabilitation (continued): • Clear Zone, Upgrade safety work to 20’ clear zone except when ADT > 2000 use AASHTO roadside design clear zone. • Inslope, 4:1 minimum, on Interregional system > 2000 ADT a 6:1 inslope is desirable where grading or roadway widening is required. • Pavement Slough, Use NDDOT shoulder treatment methods. • Safety items, Upgrade safety hardware to meet NCHRP 350 standards. New Design Guidelines
Design Guidelines • Major Rehabilitation (continued): • Regulatory and warning signs and pavement markings to MUTCD • Perform crash analysis and address cost effective enhancements • Safety items, Upgrade safety hardware to meet NCHRP 350 standards. New Design Guidelines
Design Guidelines • New/Reconstruction • ADT 20 year projection • Super elevations, Horizontal curves, clear zones pavement slough - AASHTO • Use posted speed limit • Cross Slope, Driving lanes 1.5% - 2.5%, Shoulder 6% max. • Construct to AASHTO guidelines w/all safety work. • Upgrade safety hardware to meet NCHRP 350 standards. New Design Guidelines