Bearing Capacity of Roads, Railways and Airfields

Bearing Capacity of Roads, Railways and Airfields
Author: Andreas Loizos
Publisher: CRC Press
Total Pages: 364
Release: 2017-07-20
Genre: Technology & Engineering
ISBN: 1351585797

Bearing Capacity of Roads, Railways and Airfields includes the contributions to the 10th International Conference on the Bearing Capacity of Roads, Railways and Airfields (BCRRA 2017, 28-30 June 2017, Athens, Greece). The papers cover aspects related to materials, laboratory testing, design, construction, maintenance and management systems of transport infrastructure, and focus on roads, railways and airfields. Additional aspects that concern new materials and characterization, alternative rehabilitation techniques, technological advances as well as pavement and railway track substructure sustainability are included. The contributions discuss new concepts and innovative solutions, and are concentrated but not limited on the following topics: · Unbound aggregate materials and soil properties · Bound materials characteritics, mechanical properties and testing · Effect of traffic loading · In-situ measurements techniques and monitoring · Structural evaluation · Pavement serviceability condition · Rehabilitation and maintenance issues · Geophysical assessment · Stabilization and reinforcement · Performance modeling · Environmental challenges · Life cycle assessment and sustainability Bearing Capacity of Roads, Railways and Airfields is essential reading for academics and professionals involved or interested in transport infrastructure systems, in particular roads, railways and airfields.

Effects of Moisture and Time on Stiffness of Unbound Aggregate Base Coarse Materials

Effects of Moisture and Time on Stiffness of Unbound Aggregate Base Coarse Materials
Author: Ulas Toros
Publisher:
Total Pages:
Release: 2008
Genre:
ISBN:

ABSTRACT: Resilient modulus and Young's modulus are parameters increasingly used to fundamentally characterize the behavior of pavement materials both in the laboratory and in the field. This study documents the small-strain Young's modulus and larger-strain resilient modulus response of unbound aggregate base coarse materials to various environmental conditions. The small-strain Young's modulus experiments were conducted on laboratory compacted materials and field core materials by the author. The State Material Office conducted the resilient modulus experiments on laboratory compacted materials. The results of both tests are presented in this study. It is shown that the small-strain Young's modulus is not constant, even when held at constant moisture, and that significant changes in modulus will occur with drying and wetting of the material. The response to drying and wetting cycles appears to be repeatable, and suggests that the underlying mechanism that controls the response is reversible. It is also shown that the larger-strain resilient modulus demonstrated similar trends with small-strain Young's modulus, but the rate of change and magnitude of the effect are different between materials. The material response to drying and wetting cycles appears to be reasonably repeatable. Comparisons of both experiments revealed that the change in Young's modulus with drying is much more dramatic than the resilient modulus, indicating that the drying effect is significantly reduced with higher strain. Lastly, the evidence suggests that these changes can be explained by the science of unsaturated soil mechanics: changes in moisture or moisture distribution results in changes in internal pore pressure, which affect the effective confining pressure constraining the material. The influence of this phenomenon is observed but is not as dramatic at higher strain.

Modelling of the Resilient and Permanent Deformation Behaviour of Subgrade Soils and Unbound Granular Materials

Modelling of the Resilient and Permanent Deformation Behaviour of Subgrade Soils and Unbound Granular Materials
Author: Haithem Soliman
Publisher:
Total Pages: 0
Release: 2015
Genre:
ISBN:

Laboratory characterization of subgrade soils and unbound granular materials is an essential component of the Mechanistic-Empirical Pavement Design Guide (Pavement ME). The design thickness and performance of a pavement structure are highly dependent on the deformation behaviour of subgrade and granular material. Specifications for granular materials vary among transportation agencies based on the availability of materials, climatic conditions, and function. Specifications aim to provide durable materials that meet design requirements and achieve the target design life with cost effective materials. The objectives of the research are to: • evaluate resilient modulus of typical fine-grained soils under traffic loading. • evaluate resilient modulus, permanent deformation, and permeability of typical unbound granular materials. • evaluate the effect of moisture and fines fraction on the performance of unbound granular materials and subgrade soil. • develop prediction models for resilient modulus to improve reliability of Level 2 inputs in the Pavement ME. • provide test data in support of updating Manitoba Infrastructure and Transportation specifications for unbound granular materials to improve the performance of pavement structures. Resilient modulus tests were conducted on three types of subgrade soil (high plastic clay, sandy clay, and silty sand/sandy silt) at four levels of moisture content. Resilient modulus, permanent deformation and permeability tests were conducted on six gradations representing two types of granular material (100% crushed limestone and gravel) at two levels of moisture content. Prediction models were developed for resilient modulus and compared to the models developed under the Long Term Pavement Performance program. The proposed models provided more reliable predictions with lower root mean square error. The deformation behaviour of the granular materials was classified according to the shakedown and dissipated energy approaches. Among the tested fines contents, limestone and gravel materials with optimum fines contents of 4.5% and 9%, respectively, had better resistance to plastic deformation and higher resilient modulus. The dissipated energy approach can be used to determine the stress ratio for the boundary between post compaction and stable zones from multistage triaxial testing. Result of permeability tests showed that the hydraulic conductivity of unbound granular material increased as the fines content decreased.

From Fundamentals to Applications in Geotechnics

From Fundamentals to Applications in Geotechnics
Author: D. Manzanal
Publisher: IOS Press
Total Pages: 3344
Release: 2015-12-11
Genre: Technology & Engineering
ISBN: 1614996032

The work of geotechnical engineers contributes to the creation of safe, economic and pleasant spaces to live, work and relax all over the world. Advances are constantly being made, and the expertise of the profession becomes ever more important with the increased pressure on space and resources. This book presents the proceedings of the 15th Pan-American Conference on Soil Mechanics and Geotechnical Engineering (XV PCSMGE), held in Buenos Aires, Argentina, in November 2015. This conference, held every four years, is an important opportunity for international experts, researchers, academics, professionals and geo-engineering companies to meet and exchange ideas and research findings in the areas of soil mechanics, rock mechanics, and their applications in civil, mining and environmental engineering. The articles are divided into nine sections: transportation geotechnics; in-situ testing; geo-engineering for energy and sustainability; numerical modeling in geotechnics; foundations and ground improvement; unsaturated soil behavior; embankments, dams and tailings; excavations and tunnels; and geo-risks, and cover a wide spectrum of issues from fundamentals to applications in geotechnics. This book will undoubtedly represent an essential reference for academics, researchers and practitioners in the field of soil mechanics and geotechnical engineering. In this proceedings, approximately 65% of the contributions are in English, and 35% of the contributions are in Spanish or Portuguese.

Transportation Infrastructure Engineering, Materials, Behavior and Performance

Transportation Infrastructure Engineering, Materials, Behavior and Performance
Author: Wynand JvdM Steyn
Publisher: Springer Nature
Total Pages: 209
Release: 2021-07-10
Genre: Technology & Engineering
ISBN: 3030798577

Society needs to travel to engage in productive and effective commerce, social, educational and related activities. Efficient travel is founded on an operational transport infrastructure system that is well-designed, engineering, constructed and maintained. This volume shares some of the latest innovations and thoughts in the areas of pavement infrastructure materials, behavior and performance. Access to this volume should enable the reader to gain an understanding of such novel information that should support improvements in the provision of an effective road transportation system for the benefit of the greater society served by the road network. The content is based on the contributions to the 6th GeoChina International Conference on Civil & Transportation Infrastructures: From Engineering to Smart & Green Life Cycle Solutions -- Nanchang, China, 2021.

Water in Road Structures

Water in Road Structures
Author: Andrew Dawson
Publisher: Springer Science & Business Media
Total Pages: 454
Release: 2008-10-21
Genre: Science
ISBN: 1402085621

Only book world-wide addressing this topic. The principal output of the European co-operative Action on "Water Movements in Road Pavements & Embankments". Provides unique guidance on assessing water condition and its affects on road performance. Provides unique guidance on assessing and ameliorating contaminant movement in pavement groundwater. Written by leading experts in Europe.

Bearing Capacity Of Roads

Bearing Capacity Of Roads
Author: A. Gomes Correia
Publisher: CRC Press
Total Pages: 573
Release: 2020-12-17
Genre: Architecture
ISBN: 1000108112

This book is an outcome of the sixth conference on bearing capacity of roads and airfield held in Lisbon, Portugal. It covers the following topics: bearing capacity policies, concepts, costs and condition surveys; analysis and modelling; design and environmental effects; and asphalt mixtures.