Effect Of Water In An Asphalt Road Pavement

ABSTRACT

Water has lots of adverse effects on pavement performance. In fact, moisture damage in asphalt pavements is global concern. Moisture damage can be defined as the loss of strength and durability in asphalt mixtures caused by the presence of water. Hence, it’s the need to correctly identify the problem and isolate issues of contributing factors like material variability and construction practices for a better understanding of water effect on pavement deterioration. This study has discussed some of major failure mechanisms associated with the presence of water. In addition this study has also summarized some of the widely used methodology for the evaluation of water susceptibility. It was found that the empirical nature of test methods and the inherent variability of the results are the two primary challenges that impede the reliable characterization and assessment of water effect on pavement deterioration.

TABLE OF CONTENTS

 TITLE PAGE

APPROVAL PAGE

DEDICATION

ACKNOWLEDGEMENT

ABSTRACT

TABLE OF CONTENT

CHAPTER ONE

• INTRODUCTION
• BACKGROUND OF THE PROJECT
• PROBLEM STATEMENT
• AIM/OBJECTIVE OF THE PROJECT
• SCOPE OF THE STUDY
• PURPOSE OF THE STUDY

CHAPTER TWO

LITERATURE REVIEW

2.0      LITERATURE REVIEW

2.1      REVIEW OF THE STUDY

2.2      IMPACT ON CLIMATE CHANGE PREDICTIONS

2.3      WATER EFFECTS ON ASPHALT

2.4      PAVEMENT DESIGN

2.5      MATERIAL SELECTION

2.6      PRODUCTION AND CONSTRUCTION

2.7      UNRAVELLING OF POROUS ASPHALT

2.8      RESISTANCE TO PERMANENT DEFORMATION

CHAPTER THREE

3.1      FUNDAMENTAL CONCEPTS

3.2      MOISTURE DAMAGE THEORIES

CHAPTER FOUR

4.1            TEST METHODS TO CHARACTERIZE MOISTURE SENSITIVITY

4.2            TESTS ON LOOSE MIXTURES

4.3            TESTS ON COMPACTED MIXTURES

CHAPTER FIVE

• CONCLUSIONS

CHAPTER ONE

1.0                                                        INTRODUCTION

1.1                                           BACKGROUND OF THE STUDY

When it comes to paving, Asphalt material is the most popular because of it its quality features it has such as looks good, lasts long, and is generally low maintenance.  Moisture damage can be defined as the loss of strength and durability in asphalt mixtures caused by the presence of water. Moisture damage is induced by the loss of bond between the asphalt cement or the mastic and the fine and coarse aggregate. Moisture damage accelerates as moisture permeates and weakens the mastic, making it more susceptible to moisture during cyclic loading.

Historically, six contributing mechanisms have been identified associated with moisture damage: detachment, displacement, spontaneous emulsification, pore pressure induced damage, hydraulic scour, and the effects of the environment on the aggregate–asphalt system. However, it is to be mentioned that moisture damage is not limited to a single mechanism but is the outcome of a combination of these mechanisms (Little and Jones, 2003). Santucci and Aschenbrener (2003) have identified the following factors that contribute to adverse effects of water in asphalt pavement. Finally, moisture damage mechanisms results in the following distresses like, Stripping, Bleeding, Rutting, Corrugation and Shoving, Cracking, Raveling, Localized failures.

Water damage can be defined as the loss of strength and durability in asphalt mixtures caused by the presence of water. Water damage is induced by the loss of bond between the asphalt cement or the mastic (asphalt cement, the mineral filler and small aggregates) and the fine and coarse aggregate. Water damage accelerates as moisture permeates and weakens the mastic, making it more susceptible to moisture during cyclic loading. Finally, Water damage mechanisms results in the following distresses.

• Stripping: Debonding of aggregates and binder at the bottom of HMA
• Bleeding: Formation of asphalt binder film on the
• Rutting: Surface depression along wheel
• Corrugation and Shoving: Plastic movement typified by ripples or an abrupt wave across the pavement surface.
• Cracking, Water Bleeding and
• Raveling: Progressive disintegration of HMA
• Localized failures: Progressive loss of adhesion between binder and aggregates or progressive loss of cohesion in aggregates and in

This work discuses all these deterioration in full and at the end solution for the these problems were analyzed.  In this chapter one we discussed the introductory part of the work,   chapter two presents the background and review of the related studies,  chapter three describes the methods applied,  chapter four discusses the results of the methods used, chapter five summarizes the research outcomes and the recommendations.

1.2                                                  PROBLEM STATEMENT

For a better understanding of water effect on pavement deterioration, it’s the need to correctly identify the problem and isolate issues of contributing factors like material variability and construction practices. To this end, current study is intended to discuss the mechanisms associated with water induced damages in pavement. In order to fulfill this objective, this paper addresses following issues:

• Identification of the
• Fundamental concepts- binder and aggregate interaction and representative failure
• Test methods to characterize moisture

1.3                                     AIM AND OBJECTIVE OF THE STUDY

The aim of this work is to study the effect of water on pavement made of asphaltic material. At the end of this study the student involved shall be able:

1. To analyze the effect of water in asphalt pavement
2. To analyze the solution to such effects

• To analyze methods used in repairing the deterioration

1. Identify moisture-related damage in asphalt pavement
2. Describe various methods to make asphalt pavements less susceptible to moisture damage and understand the steps to address moisture damage taken by state highway agencies
3. Discuss a cost-benefit analysis performed to determine the applicability of anti-strip additives

• Discuss the existing research related to asphalt moisture damage and identify

1.4                                                   SCOPE OF THE STUDY

When cracks form in asphalt, it allows for water to seep under the surface, which is damaging to the base beneath. Each time it rains and this happens, the weakness, damages, and pavement deterioration rate increases. This damage is often not visible from above, but the damages being caused are serious and can be costly to fix.

1.5                                                PURPOSE OF THE STUDY

The main purpose of this work is to Provide a practical discussion of moisture damage in asphalt pavements.

CHAPTER FIVE

4.1                                                          CONCLUSIONS

Water effect on pavement deterioration is a complex phenomenon involving thermodynamic, chemical, physical, and mechanical processes that contribute to pavement deterioration. This study has discussed some of major failure mechanisms associated with the presence of water. In addition this study has also summarized some of the widely used methodology for the evaluation of water susceptibility. It was found that the empirical nature of test methods and the inherent variability of the results are the two primary challenges that impede the reliable characterization and assessment of water effect on pavement deterioration. This study successfully conveys the fact that water effect on pavement deterioration is an open ended problem which is to be solved by the broader understanding of representative failure mechanism and site-specific treatments applicable to the problem.