Factors Influencing Highway Design •
•
•
•
•
•
•
•
•
•
•
Functional Classification Design hourly traffic volume and vehicle mix Design speed Design vehicle Cross section of the highway, highway, such as lanes, shoulders and medians Presence of heavy vehicles on steep grades Topography of the area that the highway traverses Level of Service Availability of funds Safety Social and environmental environmental factors factors
Urban Principal Arterial System •
C.M. Recto Avenue, serves the major activity centers of the urban area and consists mainly of the highest-traffic-volume corridors.
Urban Minor Arterial System •
Streets and highways that interconnect with and augment the urban primary arterials.
Urban Collector Street System •
Collect traffic from local streets in residential areas or in CBDs and convey it to the arterial system.
Urban Local Street System •
All other streets within the urban area
DPWH New Classification System • •
• •
•
•
•
National Primary – directly connects major cities (≥ 100,000 pop) National Secondary – directly connects national primary roads, ports, airports, secondary roads, cities, provincial capitals, national government infrastructure or other national secondary roads National Tertiary – other roads used as local function Provincial Roads – connects, cities and municipalities not along national roads, barangays through rural areas and major provincial government infrastructure Municipal and City Roads – within Poblacion, connects provincial and national roads, provide inter-barangay connections to major municipal and city infrastructure not along provincial roads Barangay Roads – Other public roads in barangays not covered by above Expressways – limited access, normally with interchanges; includes
DPWH New Classification System National Primary Roads
MC
MC Tertiary Roads
Expressways
National Secondary Roads CC
•
•
Ports, airports, ferry terminals and national government infrastructures Note: • • •
MC, major cities CC, other cities T, Town
T B B
B
High Speed Highways
•
• •
• •
Good ride quality Safe, skid-resistant surface Quiet surface Low maintenance
•
Bad Ride Quality
•
Good Ride Quality
•
General principles: • •
Large surface protrusions generate high noise High material stiffness generates high frequency noise.
•
•
•
Design reliability at least 90% to 95%. 10% to 5% chance of the actual lifespan being less than the stated value. Resurfacing is accepted as a necessity every 10-15 years.
•
Urban Roads •
•
•
•
Maintenance-friendly construction High-skid-resistance surface in places High rut resistance in places Low maintenance
•
Be possible to cut/break the road using standard equipment •
•
Strong PQC is should be avoided
Backfill to trenches should not result in a significantly poorer or less stiff construction •
Pavement should be of fairly standard type of construction.
Munro Stanley Portable Skid Resistance Tester (also known as the British Pendulum Tester) •
•
Higher than average skid resistance is typically specified are at pedestrian crossings, junctions, and roundabouts Special treatment of highfriction chippings stuck down with an ultra-tough binder
•
Take extreme care to design asphalt mixtures to resist rutting
•
•
•
Use block paving over a hydraulically-bound base Use PQC Use grouted macadam
•
•
•
Disruption of traffic is a major consideration in road maintenance. Activities such as surface dressing, slurry sealing or retexturing is acceptable as disruptions are only brief. Reliability should be high in urban roads
•
Rural Roads •
•
Adequate ride quality Suitably high skid resistance
Adequate ride quality and Skid Resistance •
•
•
For developed countries traffic speeds are at least 60-100 kph thus ride quality must be sufficient Ideally asphalt makes a good bounding material If traffic volume is low enough, roads can be entirely made of granular pavements, sealed with a surface dressing.
•
Sufficient load-bearing capacity
•
Maintain an acceptable surface finish
•
Limit uneven deformation
•
•
•
•
Limit deformation Ensure adequate skid resistance Avoid future closures Resist fuel/oil spillage Avoid foreign object damage (FOD)
•
•
Limit uneven deformation Designed for specific vehicles used as follows
