As many of the developing countries Ethiopian's road network is mostly gravel. It comprises 82.7% of the road network. Road users and residences around these roads highly exposed to the dust generated due to traffic. In the past years so many techniques of dust reduction has been applied, starting from application of water to using chemical adhesives. In this work an alternative option for dust reduction is presented. Sub base materials from Gelan-Insilale-Legedadi DS6 road section and tear off asphalt pavement from Kality-Akaki road were bagged, tagged & transferred to laboratory. In laboratory in order to determine the engineering property ASTM & AASHTO standards were used. Precipitation Data from Ethiopian National Meteorology Agency, traffic count, vehicle classification of federal highway administration and laboratory test results of silt content & particle size multiplier K-value were used for adopting EPA3 dust quantification model & fugitive dust handbook equation. MINI-TAB17& Excel
analyses were used to analyze the data. The result shows blending the 70% sub base with 30% RAP the dust emission was reduced by 17%. The method was also found to be both ecological & economical.
Table of Contents
1. Introduction
1.1 Problem statement
1.2 Research objective
1.3 Research question
1.4 Scope
1.5 Limitation of the study
2. Materials and Methodology
2.1 Materials
2.2 Methods
3. Result & Discussion
3.1 [Implicit Chapter 3.1 title based on structure: Strength and Particle Size Analysis]
3.2 Excel & MINITAB Analysis Report
3.3 Cost Comparison between RAP and Sub base material
4. Conclusions & Recommendations
4.1 Conclusions
4.2 Recommendations
Research Objectives and Themes
The primary objective of this research is to evaluate the effectiveness of incorporating reclaimed asphalt pavement (RAP) as an additive to gravel road surfacing materials to facilitate dust reduction. The study aims to address the health and environmental risks associated with high levels of traffic-generated dust on unpaved roads in Ethiopia by analyzing material engineering properties and quantifying emission reductions through established EPA models.
- Analysis of material engineering properties (CBR, shrinkage limits, and particle size distribution).
- Application of EPA dust prediction models and fugitive dust handbook equations.
- Comparative analysis of dust emissions across different vehicle classes.
- Economic and ecological feasibility assessment of using recycled asphalt pavement.
- Evaluation of 30% and 50% RAP blend ratios in sub-base materials.
Excerpt from the Book
1. Introduction
According to ERA the total road network increased from 18,081 km in 1992 G. C increased to 52,896 km in 2011 G.C. from these roads 82.7% of all the roads are gravel roads, which is Design Standard 6 (DS6) and Rural Road 50 (RR50) roads (Organizational background of ERA docR.pdf). This paper reports is a part of a research project that aims to determine the effect of adding reclaimed asphalt pavement in gravel roads in order to reduce fugitive dust generated due to traffic.
The top problems associated with gravel roads is escapee of dust & loss of fine particles. The Ethiopian roads also suffer from these problems. The main adverse impacts of traffic-generated dust from gravel roads are:
Damage to the health of road users and nearby residents
Reduced production from agriculture
Increased risk of accidents for road users
Increase in environmental damage through pollution
Deterioration in road condition
Increase in vehicle operating costs (Tony Greening, 2010).
Summary of Chapters
1. Introduction: This chapter contextualizes the prevalence of gravel roads in Ethiopia and justifies the need for dust mitigation due to health, safety, and economic impacts.
2. Materials and Methodology: This section details the laboratory experiments conducted on sub-base materials and reclaimed asphalt pavement (RAP) blends, including the testing procedures for particle size and engineering properties.
3. Result & Discussion: This chapter presents the data analysis using EPA models to compare dust emission levels and costs between standard gravel sub-base and RAP-blended materials.
4. Conclusions & Recommendations: This final chapter synthesizes the study's findings regarding strength improvements and emission reductions, offering practical suggestions for road authorities to implement RAP usage.
Keywords
dust in Ethiopia, recycled asphalt pavement, dust quantification, gravel in Ethiopia, fugitive dust, traffic-generated dust, EPA model, pavement stabilization, engineering properties, CBR, silt content, environmental impact, cost-benefit analysis.
Frequently Asked Questions
What is the core focus of this research paper?
The paper focuses on the feasibility of using reclaimed asphalt pavement (RAP) as an additive in gravel road construction to reduce traffic-generated dust.
Which specific road section was studied?
The study specifically analyzed the Gelan-Insilale-Legedadi road section in Ethiopia.
What is the primary objective of the research?
The objective is to determine whether adding RAP to gravel surfaces significantly reduces dust emissions while maintaining or improving engineering performance.
Which scientific methodology was employed?
The researchers utilized laboratory tests to determine engineering properties (CBR, gradation) and applied the EPA AP-422 dust estimation model for quantification.
What are the central thematic areas?
The themes include dust quantification, material science testing, cost analysis, and environmental/health impact assessment of unpaved road networks.
How is the dust reduction measured?
Dust reduction is measured by comparing theoretical emissions from base gravel against 30% and 50% RAP-blend ratios using standard EPA prediction equations.
What were the main engineering results of adding 30% RAP?
The study found that a 30% RAP blend met required strength criteria (CBR) and resulted in a notable reduction in dust emissions compared to natural gravel surfacing.
Is the application of RAP considered cost-effective according to the study?
Yes, the study concludes that while production costs are comparable, the potential savings in reduced maintenance, health impact, and vehicle operating costs make it an economical and ecological choice.
- Arbeit zitieren
- Genet Hailu (Autor:in), 2017, Adding Recycled Asphalt Pavements in Gravel Roads to Control Traffic Generated Dust, München, GRIN Verlag, https://www.grin.com/document/1266782