WORKABILITY

Towards a Better Understanding of Workability of Hot Mixed Asphalt

Abstract

This research paper examines the various aspects towards understanding of workability of Hot Mixed Asphalt (HMA). The study identifies the various workability devices which are essential for the measurement of materials used in the construction of roadways and pavements. Several past studies have thus observed which proposed several devices. This study intends to propose the improvements of these devices by focusing the workability on quality, time, torque, power, energy, easy, difficult, constructability, compactibility.

Table of Contents

Abstract1

Introduction3

Definition of Workability Mix Asphalt3

Discussion6

Need of Understanding Workability of HMA9

Need of Understanding Modifiers9

Abdelgalil et al., (2011) Workability Device12

Workability Index13

Usage of the Workability Devices13

Conclusion14

Towards a Better Understanding of Workability of Hot Mixed Asphalt

Introduction

The traffic volume on roads and pavements is increasing increase in population in modern civilization. This increasing volume of traffic made it imperative to take stringent measures in management of traffic volume through advanced research in properties of material used in the construction of roads and pavements. These properties range from measuring value of workability of Hot Mixed Asphalt to ensure improved workability devices.

Definition of Workability Mix Asphalt

The term workability means to assess the various those properties associated with the construction of hot mix asphalt usually known in its abbreviated form HMA. The workability is widely discussed in past literature by various scholars e.g. (Cabrera, 1992; Gudimettla, Gudimettla, Cooley & Brown, 2003:2004). Some authors describe workability in relation to the ease and difficulty properties associated with the work of HMA by hand after being placed on the roadway. Some have discussed on context of compatibility properties associated with hot mixed asphalt. The basic idea behind the definition of workability in relation to the hot mixed asphalt is to describe in context of properties that define ease of the work of HMA on its placement, working in hand and compatibility. This definition by various authors provides the platform which is applicable to define the movements of HMA through construction equipment on pavements and roads, handwork and compatibility of HMA. For desired HMA smoothness and density, it is eminent that satisfactory levels of workability be obtained within compacted pavements.

Researchers have observed that workability of asphalt mixture in terms of either torque or gyration compactor and porosity indicators. Several authors for example (Marvillet & Bougault, 1979) have used the torque for the measurement of workability. Whereas the authors for example (Cabrera, 1991, Mohamed et al., 2008; Celik & Atis, 2008) have used the gyration compactor and porosity indicators for the measurement of workability. Various authors in the past have put little focus on the measurement of workability and its influence on the temperature of compaction of hot mix asphalt (Khweir, 1991; Celik and Atis, 2008). It is necessary to understand the effect of mixing temperature on compaction of asphalt mixture for achieving the desired output levels of pavements and roadways. Several studies argue that desired level of performance can only be improved through well structured device for example the workability device used in one of the studies ...