Table Of ContentGeotechnics of Roads: Fundamentals
Geotechnics of Roads:
Fundamentals
Bernardo Caicedo
Department of Civil and Environmental Engineering
Los Andes University, Bogotá, Colombia
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LibraryofCongressCataloging-in-PublicationData
Names:Caicedo,Bernardo,author.
Title:Geotechnicsofroads:fundamentals/BernardoCaicedo.
Description:Leiden,TheNetherlands:CRCPress/Balkema,[2019]|
Includesbibliographicalreferencesandindex.
Identifiers:LCCN2018044343(print)|LCCN2018051953(ebook)|
ISBN9780429025914(ebook)|ISBN9781138600577(hardcover:alk.paper)
Subjects:LCSH:Geotechnicalengineering.|Roads–Designandconstruction.|
Roadmaterials.|Soilmechanics.
Classification:LCCTA705(ebook)|LCCTA705.C272019(print)|
DDC625.7/32–dc23
LCrecordavailableathttps://lccn.loc.gov/2018044343
ISBN:978-1-138-60057-7(hbkVolume1)
ISBN:978-0-429-02591-4(ebkVolume1)
ISBN:978-1-138-60058-4(hbkVolume2)
ISBN:978-0-429-02592-1(ebkVolume2)
ISBN:978-1-138-02956-9(hbksetof2volumes)
ISBN:978-1-315-22639-2(ebksetof2volumes)
To Gloria
Alejandro and Nicolás
Contents
Acknowledgments xiii
List of mathematical symbols xv
Introduction 1
1 Distribution of stresses and strains in roads 7
1.1 Fundamental relationships and definitions 7
1.1.1 Stresses in particulate media 7
1.1.2 Representation of stresses in a continuum media 9
1.1.3 Geometric derivation of strains 16
1.2 Fundamental definitions of elasticity 19
1.2.1 Equilibrium equations 20
1.2.2 Relationships between stresses and strains for isotropic
linear elasticity 21
1.2.3 Strain compatibility equations 24
1.3 Plane strain problems 26
1.3.1 Airy’s stress function 28
1.4 Some useful elastostatic solutions for stress distribution 31
1.4.1 Boussinesq’s solution 31
1.4.2 Cerrutti’s solution 33
1.4.3 Fröhlich solution 34
1.4.4 Stress components from triangular loads 35
1.5 Anisotropy 36
1.6 Generalities about the elastic limit 38
1.6.1 Physical meaning of a yield criterion 39
1.6.2 Representation of yield criteria in the plan of principal
stresses 40
1.6.3 Some classical yield criteria of geomaterials 41
1.7 Contact problems in road engineering 44
1.7.1 Contact between two spheres 48
1.7.2 Contact between an ellipsoid and a flat surface 48
1.7.3 Contact between a cylindrical body and an elastic half space 49
1.7.4 Internal stresses in Hertzian contacts 50
viii Contents viii
1.7.5 Non Hertzian contacts 50
1.7.5.1 Contact between a rigid cone and an elastic
half space 50
1.7.5.2 Contact between a rigid cylinder and an elastic
half-space 51
1.8 Elastodynamic solutions 52
1.8.1 Lumped spring-dashpot model 53
1.8.2 Cone macro element model 57
1.8.3 Propagation of surface waves 60
1.9 Response of a multilayer linear elastic system 62
1.10 Generalities about tire-road interaction 67
1.10.1 Theoretical basis derived from the Hertz theory 67
1.10.2 Tire interaction on bare soils 69
1.10.3 Tire interaction on pavements 72
2 Unsaturated soil mechanics applied to road materials 77
2.1 Physical principles of unsaturated soils 77
2.1.1 Potential of water in a porous media 77
2.1.2 Surface tension 78
2.1.3 Contact angle 79
2.1.4 Capillarity and Laplace’s equation 79
2.1.5 Thermophysical properties of moist air 82
2.1.6 Psychrometric equation 85
2.1.7 Raoult’s Law 86
2.1.8 Relationship between suction and relative humidity:
the Kelvin equation 88
2.1.9 Osmotic, capillary, and total suction 91
2.1.10 Dissolution of gas and tensile strength of water 92
2.1.11 Reduction of the freezing point of water 93
2.2 Water Retention Curve 94
2.2.1 Water retention curve for drainage 94
2.2.2 Water retention curve in wetting 95
2.2.3 Hysteresis of the water retention curve 95
2.2.4 Methods for measurement of suction 97
2.2.4.1 Suction plate 97
2.2.4.2 Pressure plate 99
2.2.4.3 Osmotic control 101
2.2.4.4 Vapor control 102
2.2.4.5 Tensiometers 103
2.2.4.6 Thermocouple psychrometers 103
2.2.4.7 Chilled mirror apparatus 104
2.2.4.8 Filter paper 106
2.2.4.9 Other methods 107
