5 Factors that affect pavement performance

The goal of any road construction or refurbishment is to design pavements that can perform at the most optimal level in its given environment. To create a successful pavement design, engineers must consider these 5 factors that affect how a pavement performs:

1.       The materials used

a.       Aggregate, binder and mix design

b.       Modulus of the subgrade or base grade materials the pavement will be placed on

c.        Material properties such as aggregate size, shape and gradation, aggregate cleanliness, and quality of asphalt on performance of chip seals and micro surfacing

2.       Traffic and loading

a.       Changing levels of traffic and the calibre and size of the vehicles traveling on the roadway

b.       Contact pressure, wheel load, axle configuration, and repetition of loads

3.       Environment

a.       Warmer climates with higher temperatures can cause significant differences in pavement temperature from the top to the bottom of the road. Due to these changes in temperature, stresses or cracks can occur throughout the pavement.

b.       Colder climates and temperatures can cause frost and ice to penetrate the pavement which can also cause stresses and saturation in the subgrade.

c.        The presence of snow and rain will mean that surface water will infiltrate into the subgrade. Additionally, poor drainage can cause the pavement to structurally weaken overall.

4.       Construction quality

a.       The quality of construction practices, contractor experience, and workmanship all affect the pavement quality and longevity.

5.       Structural design

Each layer of pavement has multiple functions to perform, e.g. sufficient thickness to distribute load stresses on the subgrade soil.

Different types of pavements - either flexible pavements or rigid pavements, can be chosen depending on traffic requirements.

Improper design that does not take into consideration the multitude of performance factors will lead to early failure of pavements and affect riding quality also.

Ideally, the pavement should meet the following requirements:

a.       Be structurally strong to withstand all types of stresses applied upon it

b.       Have an adequate coefficient of friction to prevent skidding of vehicles

c.        Have a smooth surface to provide comfort to road users even at high speed

d.       Produce the least noise from moving vehicles

e.       Have an impervious surface, so that sub-grade soil is well protected

f.         Be of sufficient thickness to distribute load stresses on the subgrade soil

g.        Designed with the aim of keeping maintenance costs low in the long run

Specialist pavement engineers at PMS know that pavement performance is affected by materials, environment, loading and construction as well as structural design – and it is the variability in these attributes that introduces risk. To manage and quantify these risks, PMS has developed a unique approach to pavement design, embracing fundamental materials analysis, climatic conditions, actual loading regimes and latest developments in pavement design philosophy.

A summary of the factors that affect pavement performance.

References:

B. A. Visintine et al. 2015, Factors Affecting the Performance of Pavement Preservation Treatments, viewed 28 Sept. 2022, <https://vtechworks.lib.vt.edu/bitstream/handle/10919/56449/ICMPA9-000121.PDF>

G3 Quality 2021, ISSUES AFFECTING PAVEMENT PERFORMANCE, viewed 28 Sept. 2022, <https://www.g3quality.com/issues-affecting-pavement-performance/>

T. V. Mathew 2009, Introduction to pavement design: Lecture notes in Transportation Systems, viewed 28 Sept. 2022 Engineering <https://www.civil.iitb.ac.in/tvm/1100_LnTse/401_lnTse/plain/plain.html>