Pavement Surface Friction Management g

85 Pages·2012·15.08 MB·English

Pavement Surface Friction
Managgement
ALACPA Short Course on Pavements Maintenance
ALACPA -September 2012 Solutions for a Better World
Course Objective
• Principles of Pavement Friction
• DDeessiiggnn && CCoonnssttrruuccttiioonn CCoonnssiiddeerraattiioonnss
• Pavement Evaluation
– MMetthhodd
– Equipment
• Friction Level Classification
• Maintaining High Skid-Resistance
ALACPA -September 2012 Solutions for a Better World
Pavement Roughness & Skid Resistance
• Pavement surface friction otherwise known as skid resistance or
surface roughness is the main pavement surface characteristic that
provides resistance between the aircraft tires and the ground to
minimize uncontrolled aircraft movements and controlled stops
• Discussing the effects of pavement texture with respect to friction
and hydroplaning; two common terms are used to describe the
pavement surface roughness are Macrotexture and Microtexture
• This course will discuss these two components and how they
interact with the whole dynamic system associated with the critical
tire/ground contact area that provide safe skid resistance for the
controlled stops of landing aircrafts on wet pavement
ALACPA -September 2012 Solutions for a Better World
The Dynamic System
• The dynamic system is the process of
the interaction between the airfield
ppaavveemmeenntt, tthhee aaiirrccrraafftt, aanndd tthhee ppiilloott,
working together to prevent the aircraft
from rolling, skidding or slipping across
tthhee ppaavveemmeenntt ssuurrffaaccee.
• The process envelopes the pavement
friction characteristics, the aircrafts
aeroddynamiics andd bbrakkiing capabbiilliittiies,
and the pilots ability to control the
aircraft
ALACPA -September 2012 Solutions for a Better World
The Dynamic System
ALACPA -September 2012 Solutions for a Better World
The Dynamic System
• Although the dynamic system encompasses the
pavement friction, the aircraft and the pilot, the
aircraft response depends largely on the tire-
pavement friction and the anti-skid system of the
aaiirrccrraafftt.
• The course will literally focus on “where the
aaiirrccrraafftt ttiirreess mmeeeett tthhee ggrroouunndd”;; tthhee ppaavveemmeenntt
friction system
ALACPA -September 2012 Solutions for a Better World
Friction Basic Characteristics
• Basic friction properties belonging to the
individual components of the friction component
of the system:
– Pavement surface (runway)
– Tire (aircraft)
– Contaminates (between the tire and the
ppaavveemmeenntt))
– Atmosphere (temperature, radiation; as effecting
ssttaattee ooff ccoonnttaammiinnaattiioonn))
ALACPA -September 2012 Solutions for a Better World
Pavement Friction System
• The basic friction characteristics
of the critical tire/ground contact
area, being part of the dynamic
system, influences the
aavvaaiillaabbllee ffrriiccttiioonn tthhaatt ccaann bbee
utilized by an aircraft
ALACPA -September 2012 Solutions for a Better World
System Main Components
• The three main components of the system:
– SSuurrffaaccee ffrriiccttiioonn cchhaarraacctteerriissttiiccss ((ssttaattiicc mmaatteerriiaall
properties)
– Dyynamic syystem ((relative motion of
aircraft/pavement)
– Syystem response ((aircraft performance))
ALACPA -September 2012 Solutions for a Better World
Airfield Pavement Basic Function
• Provide adequate bearing capacity
• PPrroovviiddee ggoooodd rriiddiinngg qquuaalliittiieess
• Provide good surface friction
cchhaarraacctteerriissttiiccss
• Other requirements
– Longevity
– Ease of maintenance
ALACPA -September 2012 Solutions for a Better World