Download or read book Permanent Deformation Behaviour of Unbound Granular Materials in Pavement Constructions written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A new simple design approach will be described that utilizes test results from the Repeated Load Triaxial Apparatus to establish the risk level of permanent deformations in the unbound granular layers (UGL) in pavement constructions under consideration of the seasonal effects. From this data a serviceability limit line (plastic shakedown limit) stress boundary for the unbound granular materials (UGM) was defined for different moisture contents. Below this line the material will have stable behavior. The serviceability limit line was applied in a finite-element (FE)-program FENLAP to predict whether or not stable behavior occurs in the UGM. To calculate the stress in the UGL, a nonlinear elastic model (Dresden Model), which is described in the paper, was implemented into the FE-program. The effects of changing moisture content during Spring-thaw period and asphalt temperature on pavement structural response were investigated. Additionally, permanent deformation calculations for the UGL were performed taking the stress history into consideration. The results clearly demonstrate that, for pavement constructions with thick asphalt layers, there is no risk of rutting in the granular base, even at high number of load repetitions. The study showed that the proposed design approach is a very satisfactory simple method to assess the risk against rutting in the UGL, even without the calculation of the exact permanent deformation of the pavement construction.

Download or read book Permanent Deformation Behaviour of Unbound Granular Materials in Pavement Constructions written by Sabine Werkmeister and published by . This book was released on 2003 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pavements Unbound written by Andrew Dawson and published by CRC Press. This book was released on 2014-09-01 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nearly all highway, airport, dock and industrial pavements contain large quantities of untreated aggregate in the form of unbound pavement layers. In many pavements, which are lightly or moderately trafficked, crushed rock or gravel derived aggregates comprise the majority of the construction or, in the case of unsealed pavements, all of the structure. This book provides studies of the performance and description of this material that will help the reader to better understand its characteristics and behaviour both alone and as part of the pavement structure it forms. This work will be useful to practitioners, policy makers, researchers and students. It forms a sequel to the earlier book "Unbound Aggregates in Road Construction" also published by Balkema

Download or read book Characterisation of the Deformation Behaviour of Unbound Granular Materials Using Repeated Load Triaxial Testing written by Negin Zhalehjoo and published by . This book was released on 2018 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Unbound Granular Materials (UGMs) are used in the base/subbase layers of flexible pavements for the majority of roads around the world. The deterioration of pavements increases with the increase of traffic loadings. To ensure the long-term performance and serviceability of pavement structures through a realistic design, the precise evaluation and comprehensive characterisation of the resilient and permanent deformation behaviour of pavement materials are essential. The present PhD study aims to investigate the characterisation of the resilient and permanent deformation behaviour of four road base UGMs sourced from quarries in Victoria, Australia, using Repeated Load Triaxial (RLT) testing. The triaxial system used in this study is instrumented with four axial deformation measurement transducers to achieve highly precise measurements and to evaluate the effect of instrumentation on the resilient modulus of UGMs. The resilient Poisson's ratio of the studied UGMs is also determined using a radial Hall-Effect transducer. Moreover, a series of permanent deformation tests is performed to precisely characterise the axial and radial permanent deformation behaviour of UGMs and investigate the factors that may significantly influence the accumulated axial and radial permanent deformations. Finally, three permanent deformation models incorporated with a time-hardening procedure are employed to predict the magnitude of permanent strain for multiple stress levels of the RLT test. The predictions using the employed models are then compared against the measured values to evaluate the suitability of the models and to identify the model that best predicts the strain accumulation behaviour of the tested UGMs. While this study focuses on the resilient and permanent deformation behaviour of four Victorian UGMs under repeated loading, the knowledge generated from this comprehensive investigation will contribute towards the global development of more reliable methods for evaluating the long-term performance of pavement structures and minimising road maintenance and repair costs." -- Abstract.

Download or read book Permanent Deformation Behavior of Unbound Granular Materials and Rutting Model Development written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterising the Deformation Behaviour of Unbound Granular Materials in Pavement Structures written by and published by . This book was released on 2015 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unbound Granular Materials written by A. Gomes Correia and published by . This book was released on 1999 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Performance Based Characterization of Virgin and Recycled Aggregate Base Materials written by Mohammad Ahmeduzzaman and published by . This book was released on 2016 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Characterization of the effect of physical properties on the performance such as stiffness and drainage of unbound granular materials is necessary in order to incorporate them in pavement design. The stiffness, deformation and permeability behaviour of unbound granular materials are the essential design inputs for Mechanistic-Empirical Pavement Design Guide as well as empirical design methods. The performance based specifications are aimed to design, and construct a durable and cost effective material throughout the design life of a pavement. However, the specification varies among jurisdiction depending on the historical or current practice, locally available materials, landform, climate and drainage. A literature review on the current unbound granular materials virgin and recycled concrete aggregate base construction specification has been carried out in this study. Resilient modulus, permanent deformation and permeability tests have been carried out on seven gradations of materials from locally available sources. Resilient modulus stiffness of unbound granular material at two different conditioning stress level have been compared in the study. The long term deformation behaviour has also been characterized from results of the permanent deformation test using shakedown approach, dissipated energy approach and a simplified approach. The results show improvement in resilient modulus and permanent deformation for the proposed specification compared to the currently used materials as a results of reduced fines content, increased crush count and inclusion of larger maximum aggregate size into the gradation. A significant effect of particle packing on permeability of granular materials have also been found, in addition to the effect of fines.

Download or read book Permanent Deformation Behaviour of Flexible Pavements written by Flippie Cornelius Petrus Loots Schutte and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Permanent deformation (rutting) is a pavement distress condition visible in the surfacing layer of a pavement. It occurs along the wheel path and results from the accumulation of load-induced permanent deformation developed from all individual pavement layers, including the subgrade. It is one of the major distress conditions in flexible pavements. Plenty of research regarding permanent deformation in flexible pavements exists, but it is mainly focused on asphalt surface layers and granular base, subbase, and subgrade layers. The South African National Roads Agency Ltd (SANRAL) completed the construction of seven flexible pavement sections on the R104, between the east of Pretoria and Bronkhorstspruit, during 2013. In-situ pavement response and environmental related data have been collected from these test sections ever since on a number of occasions. The seven flexible pavement structures include a natural gravel (G4) base, a high-quality graded crushed stone (G1) base, a Foam Treated Base (FTB), an Emulsion Treated Base (ETB), a Cement Treated Base (CTB), a Bitumen Treated Base (BTB), and a High Modulus Asphalt (HiMA)/Enrobe̹s A̳℗ Module Eleve̹ (EME) base. The permanent deformation behaviour of different flexible pavements relative to each other was investigated by processing, validating, and analysing the relevant in-situ pavement response and environmental related data collected from each of the SANRAL test sections. With the focus on total and base layer deformation, it was found that in terms of a short-term loading response and under normal operating conditions, bituminous pavements show superior performance to cement/bitumen stabilised pavements, while the latter performs better than granular pavements. CTB and ETB pavements are very similar with FTB pavements closely behind. The only granular exceptions are inverted crushed stone pavements, which should closely follow bituminous pavements at the top end of the performance range. For permanent deformation behaviour in terms of a longer-term recovering response, it was found that bituminous pavements tend to recover a larger amount of the permanent deformation attained after load application than granular pavements, probably due to the delayed elasticity (visco-elastic properties) of bituminous materials. The possibility of a transfer function for linking the permanent deformation behaviour of a pavement to its structural integrity was also investigated by determining a representative pavement number for each of the SANRAL test sections. It was found that the permanent deformation behaviour of flexible pavements relates relatively well to their structural integrity as a general decrease in permanent deformation (rut rate) was observed with an increase in pavement number. A negative power function for linking permanent deformation behaviour to structural integrity was proposed (y = 76.657x-0.752, R2 = 0.77). Additionally, it was found that post-compaction trafficking has a significant effect on the permanent deformation behaviour of flexible pavements during the initial stages of their life cycle; temperature variations can have a major influence on the in-situ performance and behaviour of bituminous layers, and the permanent deformation behaviour of flexible pavements correlates positively with the corresponding dynamic response as an increase in permanent deformation (rut rate) was observed with an increase in maximum dynamic deflection (positive linear function, y = 0.0361x - 2.5687, R2 = 0.92).

Download or read book Unbound Aggregates in Roads written by R.H. Jones and published by Butterworth-Heinemann. This book was released on 2016-04-20 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unbound Aggregates in Roads contains the proceedings of the International Symposium on Unbound Aggregates in Roads (UNBAR3) held at the University of Nottingham, England, on April 11-13, 1989. The papers focus on unbound aggregates used in road construction and cover topics ranging from drainage and permeability to placement and compaction of unbound aggregates, design philosophy, specification, and compliance. This book consists of 49 chapters divided into eight sections and opens with an overview of the functions of unbound aggregates in roads, followed by a discussion on the mechanical properties of different aggregates and theoretical aspects of granular materials. The following chapters focus on granular drainage layers in pavement foundations; residual stresses caused by compaction in granular materials; and alternative materials for road construction such as steel slags and natural and waste materials. The use of unbound road aggregates in various countries such as Italy, France, Germany, and Portugal is also considered. This monograph will be a useful resource for designers, aggregate producers, contractors, specification writers, and materials engineers.

Download or read book Environmental Geomechanics written by Laurent Vulliet and published by EPFL Press. This book was released on 2002-01-01 with total page 446 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bearing Capacity of Roads Railways and Airfields written by Andreas Loizos and published by CRC Press. This book was released on 2017-07-20 with total page 3209 pages. Available in PDF, EPUB and Kindle. Book excerpt: 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.

Download or read book Proceedings of the XIII International Scientific Conference on Architecture and Construction 2020 written by Angela Mottaeva and published by Springer Nature. This book was released on 2020-12-23 with total page 631 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book contains the latest studies on digitalization of transport and logistics, improving vehicle fuel efficiency, information technology and digital security, land management and cadastres, building structures, structural analysis, and energy conservation in construction. This book consists of papers presented during the XIII International Scientific Conference on Architecture and Construction 2020, which is dedicated to the 90th anniversary of Novosibirsk State University of Architecture and Civil Engineering, held on September 22–24, 2020. The book caters to researchers, scientists and industrial practitioners in the field of transportation engineering, logistics, intelligent transport systems, sustainable construction for housing and industrial buildings.

Download or read book Pavement and Asset Management written by Maurizio Crispino and published by CRC Press. This book was released on 2019-02-21 with total page 847 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pavement and Asset Management contains contributions from the World Conference on Pavement and Asset Management (WCPAM 2017, Baveno, Italy, 12-16 June 2017). For the first time, the European Pavement and Asset Management Conference (EPAM) and the International Conference on Managing Pavement Assets (ICMPA) were joining forces for a global event that aimed not only at academics and researchers, but also at practitioners, engineers and technicians dealing with everyday tasks and responsibilities related to transport infrastructures pavement and asset management. Pavement and Asset Management covers a wide range of topics, from emerging research to engineering practice, and is grouped under the following themes: - Data quality and monitoring - Economics, political and environmental management, strategies - Deterioration models - Key performance indicators - PMS-case studies - Design and materials - M&R treatments - LCA & LCCA - Risk and safety - Bridge and tunnel management - Smart infrastructure and IT Pavement and Asset Management will be valuable to academics and professionals interested and/or involved in issues related to transport infrastructures pavement and asset management.

Download or read book Geotechnical Engineering in the XXI Century Lessons learned and future challenges written by N.P. López-Acosta and published by IOS Press. This book was released on 2019-11-26 with total page 3006 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first Pan-American Conference on Soil Mechanics and Geotechnical Engineering (PCSMGE) was held in Mexico in 1959. Every 4 years since then, PCSMGE has brought together the geotechnical engineering community from all over the world to discuss the problems, solutions and future challenges facing this engineering sector. Sixty years after the first conference, the 2019 edition returns to Mexico. This book, Geotechnical Engineering in the XXI Century: Lessons learned and future challenges, presents the proceedings of the XVI Pan-American Conference on Soil Mechanics and Geotechnical Engineering (XVI PCSMGE), held in Cancun, Mexico, from 17 – 20 November 2019. Of the 393 full papers submitted, 335 were accepted for publication after peer review. They are included here organized into 19 technical sessions, and cover a wide range of themes related to geotechnical engineering in the 21st century. Topics covered include: laboratory and in-situ testing; analytical and physical modeling in geotechnics; numerical modeling in geotechnics; unsaturated soils; soft soils; foundations and retaining structures; excavations and tunnels; offshore geotechnics; transportation in geotechnics; natural hazards; embankments and tailings dams; soils dynamics and earthquake engineering; ground improvement; sustainability and geo-environment; preservation of historic sites; forensics engineering; rock mechanics; education; and energy geotechnics. Providing a state-of-the-art overview of research into innovative and challenging applications in the field, the book will be of interest to all those working in soil mechanics and geotechnical engineering. In this proceedings, 58% of the contributions are in English, and 42% of the contributions are in Spanish or Portuguese.

Download or read book Introduction to Unmanned Aircraft Systems Second Edition written by Douglas M. Marshall and published by CRC Press. This book was released on 2015-10-26 with total page 1944 pages. Available in PDF, EPUB and Kindle. Book excerpt: The proliferation of technological capability, miniaturization, and demand for aerial intelligence is pushing unmanned aerial systems (UAS) into the realm of a multi-billion dollar industry. This book surveys the UAS landscape from history to future applications. It discusses commercial applications, integration into the national airspace system (NAS), System function, operational procedures, safety concerns, and a host of other relevant topics. The book is dynamic and well-illustrated with separate sections for terminology and web- based resources for further information.

Download or read book Eleventh International Conference on the Bearing Capacity of Roads Railways and Airfields written by Inge Hoff and published by CRC Press. This book was released on 2022-07-07 with total page 673 pages. Available in PDF, EPUB and Kindle. Book excerpt: Innovations in Road, Railway and Airfield Bearing Capacity – Volume 3 comprises the third part of contributions to the 11th International Conference on Bearing Capacity of Roads, Railways and Airfields (2022). In anticipation of the event, it unveils state-of-the-art information and research on the latest policies, traffic loading measurements, in-situ measurements and condition surveys, functional testing, deflection measurement evaluation, structural performance prediction for pavements and tracks, new construction and rehabilitation design systems, frost affected areas, drainage and environmental effects, reinforcement, traditional and recycled materials, full scale testing and on case histories of road, railways and airfields. This edited work is intended for a global audience of road, railway and airfield engineers, researchers and consultants, as well as building and maintenance companies looking to further upgrade their practices in the field.