This document discusses elements of pavement materials and technology that should be considered in developing a green highway rating system. It identifies recycled materials and regional materials as the most suitable elements based on their ability to optimize sustainable design. The document also examines several existing green highway rating systems and compares their treatment of materials and pavement technology elements. Understanding the treatment of these elements in different rating systems can help identify important elements to include in a new rating system.

1. Pavement Materials and Technology Elements in the Rating System
Green Highway-A Conspectus
Writer : Mastura Bujang, Mohd Rosli Hainin, Mohammadreza Yadollahib, Muhd Zaimi Abd. Majidb,
Rosli Mohamad Zinb, Wan Nur Aifa Wan Azahar
Country : Malaysia
Source : www.jurnaltechnology.utm.my
As the effects of global warming and climate change are becoming a serious problem
nowadays, most countries are trying to develop their own green road scoring systems to
implement sustainable practices on their roads. Several studies have addressed issues related
to sustainable rating systems, but no major studies have been conducted to examine green
highway scoring systems in depth. Materials and pavement technology are the two most
important parameters in a green highway scoring system and need to be addressed more
critically. This study provides an extensive review to identify and define the most appropriate
pavement material and technology elements to consider in developing a green highway rating
system. Relevant literature has been reviewed to assist in identifying the elements of pavement
materials and technology. These elements in the existing green road scoring system are
tabulated and ranked to indicate the importance of each element. Understanding the
comparison between these elements in existing green road scoring systems will assist in
identifying and addressing element scarcity. Furthermore, a complete roadway rating system
can be developed as a performance measure or basic reference to suit different weather and
environments. The results showed that the most suitable elements in material and pavement
technology in highway construction were recycled materials and regional materials. These
elements can optimize sustainable design,
Increasing global demand has been reported in passenger and freight transport
activities by the United Nations Environment Program. Unfortunately, such an increase in
transport demand results in the consumption of more than half of global liquid fossil fuels and
consumes nearly a quarter of global energy-related carbon dioxide (CO2) which is predicted
to double by 2050. Figure 1 highlights the massive energy consumption and changing trends
transportation and other sectors between 2007 and 2030.
Transportation is a big contributor to environmental impacts, especially CO. the harmful
emissions that will increase global warming. Transport is thought to consume 22 percent of
global energy, burn about 25 percent of fossil fuels, and release 30 percent of air pollution and
greenhouse gases. These factors contribute to growing concerns about the depletion of natural

2. and non-renewable resources, global climate change, ecosystem disruption and toxic pollution.
As increased income is associated with higher levels of car ownership and use and greater
travel and distances, transport activity and CO emissions can increase significantly with
economic growth and consumer influence.
Therefore, sustainable practices must be implemented to reduce this impact on the environment
and also achieve a green highway. There are programs and tools available to promote
sustainability, such as the Leadership in Energy and Environmental Design (LEED) rating
system developed by the United States Green Building Council (USGBC). However, LEED is
a scoring system for sustainable building practices and operations only. The rating system has
been used in building construction initially and is gradually being applied to infrastructure
works and the transport sector in particular.
Envision is a rating system for sustainable infrastructure involving water storage and
treatment, energy generation, landscaping, transportation, and information systems. The
system drives the application of life cycle analysis throughout the planning, design,
construction and operation stages to improve green performance . There are 60 credits
distributed across five categories and Envision awards four certifications for each project that
applies criteria including Recognition of Merit, Silver Award, Gold Award, and Platinum
Award.
Another green highway tool called the Infrastructure Voluntary Evaluation
Sustainability Tool (INVEST) was developed by the Federal Highway Administration
(FHWA) and CH2M Hill in 2012. It is specifically designed for the planning, project
development, operation and maintenance phases with a total of 51 or 60 criteria depending on
basic or extended scorecard used. In addition, this system also provides certification levels
based on the scores obtained for each criterion in each project, namely Bronze, Silver, Gold
and Platinum.
This paper focuses on the six highway rating systems mentioned above, namely;
Greenroads, I-LAST, GreenLITES, GreenPave, Envision and INVEST. According to this
scoring system, material and pavement technology is one category that needs to be addressed
more critically because every highway project involves consuming resources and applying
several techniques in its construction plan. However, the issues that need to be raised here are
how green highways are built, how much natural resources can be conserved, what green
techniques can be applied to reduce energy consumption in highway projects, and what are
the most appropriate elements that need to be addressed. . considered in highway construction.
This paper identifies and compares elements of green materials and pavement

3. technologies used in existing green highway assessment systems that can be implemented so
that sustainable development in highway construction can be achieved. Extraction of relevant
information from the literature review helps identify the level of importance and appropriate
elements in pavement materials and technologies that can be considered in a green highway
assessment tool.
Pavement material and technology elements must be a serious concern by all parties
involved in road construction. A thorough review of the sustainable elements in materials and
pavement technologies can increase understanding of the green road concept among road
practitioners.
Recycling existing pavement materials during road rehabilitation and reconstruction
provides a more sustainable alternative to conventional methods such as full removal and
replacement of pavement materials. The existing damaged asphalt surface can be crushed and
mixed with base materials to form a new recycled base layer known as recycled pavement
material (RPM). On-site highway material recycling is actually a cost-effective and
environmentally friendly, thereby reducing energy consumption, greenhouse gas emissions and
disposal of waste materials. However, asphalt binder in RPM and fines in gravel road surfaces
can affect the strength, stiffness and plastic deformation of recycled materials used as base
layers.
One method to improve the performance of these recycled road materials is chemical
stabilization with binders such as: cement, asphalt emulsion, lime, cement kiln dust or fly ash.
In addition, the utilization of industrial by-products such as fly ash, steel slag, rubber, glass, etc.
can reduce transportation, energy consumption and emission of harmful gases such as CO2
greenhouse gas. In addition, it also minimizes the amount of waste material that will be disposed
of in the TPA. The performance of plastic asphalt roads conclusively proves that it is good for
heavy traffic due to better bonding, increased strength and better surface conditions for long
periods of exposure to variations in climate change.
Indeed, the process will help get rid of plastic waste usefully and easily. The higher the
recycling value, the more economically viable it can be obtained from recycling or reuse. In
addition, the use of Reclaimed Asphalt Pavement (RAP) and Recycled Concrete Material
(RCM) to produce new pavement can actually minimize the disposal of RAP and RCM waste
in TPA, reduce the consumption of virgin materials, and protect the environment both using the
Hot In-Place Recycling (HIPR) method. ) or Cold in-Place Recycling (CIPR). By practicing
this recycling technique, there is no excess material to transport and can reduce fuel &
transportation costs.

4. The use of local materials on site such as soil during embankment and embankment
balancing work has driven the reduction of transportation costs for transporting soil, reducing
energy consumption by equipment and minimizing the total project cost. Longevity pavements
can ultimately reduce maintenance costs and life cycle costs and can avoid frequent pavement
rehabilitation. It can also guarantee a high level of safety for road users.
Cold pavement is always associated with an 'albedo', which can be defined as solar
reflectance, where a higher albedo indicates a high reflectance of solar energy by the pavement
and vice versa. The tendency of high reflected sunlight energy will lower the ambient air
temperature and can avoid the heat island effect. The use of the warm mix asphalt (WMA)
technique allows a reduction in the mixing energy required and further results in substantial
energy cost savings. This allows production temperatures to be 10°C to 37.8°C lower than
conventional hot mix asphalt (HMA) production temperatures. In addition, this lower
temperature can actually save burner fuel by up to 35%.
One element of pavement technology is permeable pavement where this type of
pavement is responsible for improving water flow control, especially during high rainfall
intensity and quality of rainwater runoff. In addition, they must meet the needs of rainwater
while providing a hard surface, which can be utilized in urban areas. Permeable pavement is a
watertight alternative to traditional asphalt and concrete pavements. The interconnected voids
of the pavement allow water to infiltrate into subsurface storage zones during rainfall events.
In areas with highly permeable soil layers, the captured water seeps into the subsoil. In areas
containing soils of lower permeability, water can leave the pavement through the underdrain
system. Compared to conventional asphalt, permeable pavement provides more effective peak
flow reduction (up to 42%) and longer service time. There is also a significant reduction of
evaporation and surface water splashing as well. In addition, the concentrations of Total
Suspended Solid (TSS), total metal, and phosphorus were found to be significantly lower in the
runoff generated from the Permeable Friction Course (PFC) surface than in the runoff from the
conventional hot mix asphalt surface based previously. research. There is also a significant
reduction of evaporation and surface water splashing as well. In addition, the concentrations of
Total Suspended Solid (TSS), total metal, and phosphorus were found to be significantly lower
in the runoff generated from the Permeable Friction Course (PFC) surface than in the runoff
from the conventional hot mix asphalt surface based previously. research. There is also a
significant reduction of surface water evaporation and splashing as well. In addition, the
concentrations of Total Suspended Solid (TSS), total metal, and phosphorus were found to be
significantly lower in the runoff resulting from the Permeable Friction Course (PFC) surface

5. than the runoff from the conventional hot mix asphalt surface on a prior basis. research.
Another element in pavement technology is quiet pavement, which can result in reduced
noise resulting from the interconnection between tires and pavement. Noise generated by the
interaction between tires and pavement becomes the dominant source when the vehicle speed
is at a speed of 35 km/hour. Therefore, many transportation agencies are investigating pavement
noise reduction to reduce road traffic noise. Experience reported from the United States,
Europe, and Japan shows that noise-reducing sidewalks can reduce traffic noise levels
significantly. This pavement includes rubber asphalt, open graded asphalt, and masonry asphalt.
Noise level is affected by vehicle speed where increasing vehicle speed can produce higher
noise levels. Therefore, by introducing quiet pavement on green roads, it will control and reduce
the noise level on our highways.
Soil biotechnology is a scientific discipline dealing with hillsides, riverbanks and the
stabilization of earth embankments, which in recent decades has gained worldwide popularity.
Its uniqueness consists in the technical use of vegetation, sometimes in combination with other
materials. Due to the aesthetic and environmentally friendly characteristics of vegetation, soil
bioengineering techniques are often adopted to achieve low environmental impact of protective
works in the field of landscape architecture and environmental restoration.
In the elements of bioengineering techniques, the focus is on slope protection and
landscape development. In slope protection it is advisable to protect the soil or embankments
by using greening techniques such as turfing, planting native vegetation, gabion walls, and
hydro seeding. Utilization of soil bioengineering treatment, which is a combination of plant
materials and structural elements, can actually contribute to slope protection, stabilization and
erosion control as well.
WMA is one of the technologies that can be used in road pavement construction projects
to realize sustainable green highways. In 1997, European countries began experimenting with
WMA. The concept of WMA is that considerable energy is spent heating the HMA to a
temperature of over 150 °C during production and compaction. By reducing heating
temperatures during production by 16 to 55°C lower than typical HMA, WMA can provide
significant energy savings for the asphalt industry as well. WMA has the potential to reduce the
viscosity of the binder as well as reduce the short-term aging of the blend during production.
Therefore, several fields and experimental work have been carried out to determine and evaluate
the performance of WMA mixtures. Besides that, WMA provides a 24% reduction in HMA's
air pollution impact and an approximately 18% reduction in fossil fuel consumption. WMA can
also reduce the environmental impact of HMA by 15%.

6. Life cycle impact is used as a criterion for selecting products and materials because of
their importance. Therefore, a widely used standard method for comprehensively evaluating the
environmental impact of products can be defined as a life cycle assessment (LCA). All product
life cycles involving environmental concerns such as water, soil, waste, air, use of raw
materials, and exploitation of nature are considered. In addition, this method can help avoid
misallocation and reduce possible environmental impacts. LCA comprises the complete life
cycle of a product, from initial production, manufacture, transportation and distribution, then
reuse and recycling of materials, and finally disposal of materials.
It is possible to study the entire system life cycle using LCA techniques. Based on the
previous studies that have been discussed, it is proven that all elements in road pavement
materials and technology provide more benefits to the economy, society, and the environment
in order to realize a green highway. In addition, these elements also apply to be selected and
used in the green highway scoring system.
Pavement materials and elements of sustainable highway technology during the
planning, design, construction, operation, and maintenance phases are derived from six current
green road assessment systems, including Greenroads, GreenLITES, I-LAST, GreenPave,
Envision, and INVEST. The concept of elements used in highway construction consists of two
categories, namely pavement material resources and technology. Based on the results obtained,
the most appropriate and recommended green elements to be practiced in the green highway
assessment system are recycled materials and regional materials. The application of elements
in green materials and road pavement technology can actually effectively reduce emissions of
harmful gases and substances, which has good economic, community and environmental
impacts. Besides that, the use of environmental protection materials and road pavement
technologies such as recycling techniques can reduce environmental pollution more broadly.
Therefore, all of these elements are feasible to be applied or applied in any road construction
project. In addition, these elements can form the basis for developing a complete green road
scoring system in the future and can be applied to sustainable practices in road construction.