GEOTECHNICS OF ROADS: FUNDAMENTALS

Summary

At first glance, roads seem like the simplest possible geotechnical structures. However, analysis of these structures runs up against complexities related to the intense stresses experienced by road surfaces, their intense interaction with climate, and the complicated behavior of the materials used in road construction.

Modern mechanistic approaches to road design provide the tools capable of developing new technical solutions. However, use of these approaches requires deep understanding of the behavior of constituent materials and their interaction with water and heat which has recently been acquired thanks to advances in geotechnical engineering. The author comprehensively describes and explains these advances and their use in road engineering in the two-volume set Geotechnics of Roads, compiling information that had hitherto only been available in numerous research papers.

Geotechnics of Roads: Fundamentals presents stresses and strains in road structures, water and heat migration within and between layers of road materials, and the effects of water on the strength and stiffness of those materials. It includes a deep analysis of soil compaction, one of the most important issues in road construction. Compaction accounts for only a small proportion of a construction budget but its effects on the long-term performance of a road are decisive. In addition, the book describes methodologies for nondestructive road evaluation including analysis of continuous compaction control, a powerful technique for real-time quality control of road structures.

This unique book will be of value to civil, structural and geotechnical engineers worldwide.

Table of Contents

1 Distribution of stresses and strains in roads
1.1 Fundamental relationships and definitions
1.2 Fundamental definitions of elasticity
1.3 Plane strain problems
1.4 Some useful elastostatic solutions for stress distribution
1.5 Anisotropy
1.6 Generalities about the elastic limit
1.7 Contact problems in road engineering
1.8 Elastodynamic solutions
1.9 Response of a multilayer linear elastic system
1.10 Generalities about tire-road interaction

2 Unsaturated soil mechanics applied to road materials
2.1 Physical principles of unsaturated soils
2.2 Water Retention Curve
2.3 Flow of water and air in unsaturated soils
2.4 Heat transport and thermal properties of unsaturated soils
2.5 Mechanical properties of unsaturated soils
2.6 Modeling the behavior of unsaturated soils using the Barcelona Basic Model, BBM

3 Compaction
3.1 Mechanical framework of soil compaction
3.2 Stress distributions
3.3 Relationships between soil compaction and stress paths
3.4 Relationships between laboratory and field compaction
3.5 Compaction interpreted in the framework of unsaturated soil mechanics
3.6 Compaction characteristics for fine grained soils
3.7 Compaction characteristics for granular soils
3.8 Compaction controlled by the degree of saturation

4 Embankments
4.1 Embankments on soft soils
4.2 Behavior of the fill of the embankment

5 Mechanical behavior of road materials
5.1 From micromechanics to macromechanics
5.2 Laboratory characterization of road materials
5.3 Modeling the mechanical behavior of road materials
5.4 Geomechanical approach to ranking of road materials

6 Climate effects
6.1 Heat flow over road structures
6.2 Flow of water in road structures
6.3 Thermo-Hydro-Mechanical modeling applied to pavement structures
6.4 Empirical method based on the Thornthwaite Moisture Index
6.5 Frost action
6.6 Basic principles for road structure sub-drainage

7 Non destructive evaluation and inverse methods
7.1 Non destructive evaluation
7.2 Methods based on electromagnetic waves
7.3 Forward and inverse analysis of road structures
7.4 Continuous Compaction Control and Intelligent Compaction CCC/IC