Download or read book Assessment of Recycled Aggregates for Use in Unbound Subbase of Highway Pavement written by Vahid Ayan and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Intendancy for sustainability has made it necessary for the highways industry to adapt its traditional processes to more cost-effective, energy efficient and greener technologies. This research programme was developed with a key aim of investigating the technical viability of aggregates formed with different combinations of Recycled Concrete Aggregate (RCA), Reclaimed Asphalt Pavement (RAP) and Natural Aggregates (NA) when used in construction of unbound subbases of highway pavements. As strongly evident from a comprehensive literature review carried out, little information is available on the application of RCA and RCA/RAP as subbase materials. The suitability of RCA blended with RAP and NA were investigated and compared to the British Standards, Highway Agency specifications and the AASHTO standards requirements for highway design. Having established their suitability for highway design, then the performance of the materials was assessed under traffic loading. In compliance with the requirements of the above Standards/Specifications the in-situ loaded behavior of the aforementioned materials were also investigated. This was achieved through numerical analysis of a typical pavement structures comprising subbases made of the above materials. As a consequence, a series of analyses were carried out using KENLAYER TM computer program to model the stresses and deformations in the subbases. The results of the analyses were then applied to the Mohr Coulomb failure model in order to predict the factor of safety against failure of the subbase layer. Amongst the salient findings from the research was that most of the materials tested complied with the standard requirements. From a large number of tests carried out on materials collected in the UK and Iran, it was also demonstrated that the source of a recycled material and the method of extraction had a significant influence on the engineering properties of the material, especially the CBR. In terms of compaction and CBR requirements, the 50%RAP+50%RCA mix was demonstrated as suitable for unbound subbase application. Also, the presence of RAP in the mixes of RAP/RCA was found to improve the drainage properties of an unbound subbase layer. From the viewpoint of durability and frost susceptibility, it was verified that all the materials investigated were applicable to the highest significance level (as defined by AASHTO). However, based on stiffness considerations, the materials were found to be applicable only to the lowest significance level. Now, turning to the toughness and shear strength properties, the same materials were found to fall in the middle significance levels. The results of KENLAYER TM modeling indicated that the safety factor against failure of the mixes containing RAP and RCA decreased as the stiffness decreased. Evidently the research is likely to have a number of implications on the design and construction of highways. Firstly, the demonstrated viability of mixes containing recycled materials (RCA+RAP) can lead to significant cost savings, reduced CO2 emissions, reduced exploitation of virgin materials and minimization of dumping of civil engineering waste. If embraced in industry, the suggested use of recycled materials can help support National and international targets regarding sustainability, environmental and energy conservation. The research succeeded in cataloguing the specifications of RCA/RAP and RCA/NA for practical works, followed by development and evaluation of different mixes of recycled aggregates obtained from different sources. Detailed assessment based on compliance with requirements, performance prediction and modeling was completed.

Download or read book Performance related Tests of Recycled Aggregates for Use in Unbound Pavement Layers written by Athar Saeed and published by Transportation Research Board National Research. This book was released on 2008 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explores performance-related procedures to test and select recycled hot-mix asphalt and portland cement concrete materials for use in unbound layers of highway pavements. Appendixes A through C of NCHRP Report 598, which cover the literature review and background information, new aggregate tests, and surface dielectric measurements, were published as NCHRP Web-Only Document 119.

Download or read book Recycled Aggregates in Highway Pavement written by Vahid Ayan and published by LAP Lambert Academic Publishing. This book was released on 2014-12-15 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive research was performed on application of demolished construction wastes in road pavement layers. The research succeeded in cataloging the specifications of recycled aggregates mixes for practical works, followed by development and evaluation of different mixes of recycled aggregates obtained from different sources. Detailed assessment based on compliance with requirements, performance prediction and modeling was completed. Evidently the research is likely to have a number of implications on the design and construction of highways. Firstly, the demonstrated viability of mixes containing recycled materials can lead to significant cost savings, reduced carbon footprint, reduced exploitation of virgin materials and minimization of dumping of civil engineering waste. If embraced in industry, the suggested use of recycled materials can help support national and international targets regarding sustainability, environmental and energy conservation.

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 Appendixes to NCHRP Report 598 written by Athar Saeed and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This document contains appendixes A through C of NCHRP Report 598, "Performance-Related Tests of Recycled Aggregates for Use in Unbound Pavement Layers." The appendixes cover the literature review and background information, new aggregate tests, and surface dielectric measurements associated with NCHRP Report 598.

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 Pavement Design and Materials written by A. T. Papagiannakis and published by John Wiley & Sons. This book was released on 2017-02-22 with total page 555 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive, state-of-the-art guide to pavement design and materials With innovations ranging from the advent of SuperpaveTM, the data generated by the Long Term Pavement Performance (LTPP) project, to the recent release of the Mechanistic-Empirical pavement design guide developed under NCHRP Study 1-37A, the field of pavement engineering is experiencing significant development. Pavement Design and Materials is a practical reference for both students and practicing engineers that explores all the aspects of pavement engineering, including materials, analysis, design, evaluation, and economic analysis. Historically, numerous techniques have been applied by a multitude of jurisdictions dealing with roadway pavements. This book focuses on the best-established, currently applicable techniques available. Pavement Design and Materials offers complete coverage of: The characterization of traffic input The characterization of pavement bases/subgrades and aggregates Asphalt binder and asphalt concrete characterization Portland cement and concrete characterization Analysis of flexible and rigid pavements Pavement evaluation Environmental effects on pavements The design of flexible and rigid pavements Pavement rehabilitation Economic analysis of alternative pavement designs The coverage is accompanied by suggestions for software for implementing various analytical techniques described in these chapters. These tools are easily accessible through the book’s companion Web site, which is constantly updated to ensure that the reader finds the most up-to-date software available.

Download or read book Tests of Recycled Aggregates for Use in Unbound Pavement Layers written by Athar Saeed and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Sustainable Construction Materials written by Ravindra K. Dhir OBE and published by Woodhead Publishing. This book was released on 2019-01-05 with total page 652 pages. Available in PDF, EPUB and Kindle. Book excerpt: Sustainable Construction Materials: Recycled Aggregate focuses on the massive systematic need that is necessary to encourage the uptake of recycled and secondary materials (RSM) in the construction industry. This book is the fifth and the last of the series on sustainable construction materials and like the previous four, it is also different to the norm. Its uniqueness lies in using the newly developed, Analytical Systemisation Method, in building the data-matrix sourced from 1413 publications, contributed by 2213 authors from 965 institutions in 67 countries, from 1977 to 2018, on the subject of recycled aggregate as a construction material, and systematically analysing, evaluating and modelling this information for use of the material as an aggregate concrete and mortar, geotechnics and road pavement applications. Environmental issues, case studies and standards are also discussed. The work establishes what is already known and can be used to further progress the use of sustainable construction materials. It can also help to avoid repetitive research and save valuable resources. The book is structured in an incisive and easy to digest manner and is particularly suited for researchers, academics, design engineers, specifiers, contractors, and government bodies dealing with construction works. Provides an exhaustive and comprehensively organized list of globally-based published literature spanning 5000 references Offers an analysis, evaluation, repackaging and modeling of existing knowledge that encourages more responsible use of waste materials Provides a wealth of knowledge for use in many sectors relating to the construction profession, including academia, research, practice and adoption of RSM

Download or read book Comparison of Specifications for Recycled Concrete Aggregate for Pavement Construction written by A. R. Gabr and published by . This book was released on 2011 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper reviews existing specifications, specifically for the application of crushed concrete or recycled concrete aggregate (RCA) as pavement material for unbound subbases and basecourses. While the use of recycled crushed concrete is not new internationally, its application in Australia is unique as it is being commonly used as a granular basecourse/subbase supporting thin bituminous seals (asphalt or spray seal/chip seal). Commonality of specifications is explored and differences that exist are questioned. In light of practice outside of Australia, limitations by Australian authorities placed on recycled material inclusions other than crushed concrete are raised. In this paper, two South Australian-based RCA products, which were designed for use as pavement bases, are compared with current engineering specifications. The RCA products performed well in terms of resilient modulus and permanent deformation. However, properties such as abrasion resistance and wet/dry strength may restrict the application of the material if current specifications are justifiable.

Download or read book Sustainable Alternative Materials in Unbound Granular Layers of Pavement Structures written by Adam C. Schneider and published by . This book was released on 2017 with total page 196 pages. Available in PDF, EPUB and Kindle. Book excerpt: In Part 1 of this thesis, reclaimed cement concrete (commonly referred to as recycled concrete aggregate or RCA) and reclaimed asphalt pavement (RAP) are investigated as potential alternative construction materials for Granular B Type II subbase fill. Ontario Provincial Standard Specification (OPSS) 1010 currently allows the common use of processed reclaimed construction materials in a variety of road base, subbase and asphaltic concrete layers, with the notable exception of Granular B Type II, which at present may only include 100% crushed bedrock, talus, iron blast furnace slag or nickel slag. As more restrictions are placed on zoning and approvals for new natural aggregate extraction sites in Ontario, there is a need to better understand the performance of materials such as RCA and RAP as economically beneficial potential aggregate sources for granular base and subbase fill layers. An experimental program was created to assess and analyze the performance characteristics of a series of different subbase test mixtures incorporating RCA and/or RAP, either pure or blended with crushed bedrock, and the impact of the inclusion of these materials when compared to a conventional 100% crushed bedrock test mix meeting OPSS 1010 requirements for Granular B Type II. The performance characteristics to be assessed were field compactibility, gradations before and after field compaction, physical properties, standard and modified Proctor tests, California Bearing Ratio (CBR), permeability, resilient moduli and lightweight deflectometer (LWD) resilient moduli. Field testing programs conducted at Quarry 1 in Ottawa, Ontario and Quarry 2 in Burlington, Ontario indicate that the subbase test mixtures meeting OPSS Granular B Type II gradation requirements and incorporating different proportions of crushed rock, RCA and/or RAP exhibit similar field rolling compactibility relative to 100% crushed rock. Grain size analysis testing showed some aggregate breakdown in multiple test mixes, with only minimal increases in material passing the 75 μm sieve, which is crucial to preserving permeability and drainage characteristics. Tests using a lightweight deflectometer (LWD) were subject to substantial variability but indicated that mixes using elevated levels of RCA (50% and 100%) can potentially have lower in-situ moduli compared to the other blends tested. Laboratory tests indicate that high replacement levels of RCA can be used in subbase materials as a substitute for 100% crushed rock while maintaining good water permeability characteristics and similar or higher resilient moduli in blends incorporating RCA and/or RAP. CBR testing results were similar across all test blends incorporating crushed rock and RCA, but also indicated that the inclusion of 30% RAP can potentially reduce the bearing capacity of the granular material by approximately 30-40% in comparison to all other blends which do not contain RAP. Based on the overall results of this study, RCA and RAP appear to be capable of successfully substituting for natural aggregates in Granular B Type II in a range of compositional proportions. It is recommended that test sections should be completed on highway contracts with subbase mixture blends incorporating RCA and/or RAP in order to verify their performance in pavement structures in the field. In Part 2 of this thesis, foam glass lightweight aggregates (LWA) are investigated as a potential pavement engineering design alternative in order to mitigate roadway loading impacts upon underlying subgrade soils while promoting the sustainable and economical use of recycled waste glass. Foamyna Canada Inc. supplied the Centre for Pavement and Transportation Technology (CPATT) with two foam glass lightweight aggregate materials, designated in this thesis as LWA-A and LWA-B. Physical properties testing was carried out by CPATT, including grain size analysis, crushed particle content, flat and elongated particle content, Micro-Deval abrasion resistance, cyclic freezing-and-thawing resistance and resilient modulus testing procedures. These procedures were conducted in order to evaluate the LWA materials against locally applicable standards, namely Ontario Provincial Standard Specification document OPSS 1010 as currently used by the Ministry of Transportation of Ontario (MTO). The laboratory testing detailed in Part 2 indicates that both LWA-A and LWA-B have a very consistent and repeatable gradation with a high percentage of coarse aggregates. Both foam glass materials have very high crushed particle contents and very low flat and elongated particle contents. Micro-Deval abrasion resistance, freeze-and-thaw resistance and resilient moduli were also excellent for both materials, while relative density testing indicated LWA material specific gravity values which were substantially lower than that of water. However, it was found that the gradations of these two tested materials do not satisfy the existing requirements of OPSS 1010, which were developed for natural aggregates and, as currently constituted, may not be appropriately adapted to artificial lightweight aggregates. The coarse nature of the LWA materials would be highly beneficial to ensure the stability of the granular layers and prevent upward capillary water movement into other layers of the pavement structure. Pavement design calculations were carried out using the AASHTO 1993 empirical design procedure and found that utilizing foam glass LWA as a lightweight subgrade replacement fill material can result in substantially leaner pavement structures as compared to the use of conventional expanded polystyrene (EPS) geofoam blocks as an artificial subgrade. A life-cycle cost analysis (LCCA) procedure carried out on these pavement designs showed that the use of foam glass LWA as a lightweight fill material underlying pavement can result in overall cost savings of over 30 percent relative to pavement structures which are underlain by EPS geofoam. Overall, the two tested LWA materials showed excellent physical and mechanical characteristics, and would be suitable for use in pavement structures as innovative lightweight and environmentally friendly alternatives to natural aggregate materials.

Download or read book Infrastructure Management Assessment and Rehabilitation written by Sherif Yehia and published by Cambridge Scholars Publishing. This book was released on 2021-11-30 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume brings together state-of-the-art research on the development of infrastructure management, assessment, and rehabilitation techniques. It sheds light on pioneering work on innovative 3D-printed concrete, novel methods for assessment of bridge decks, and advanced computer vision-based maintenance of civil infrastructure. The book is essential reading for infrastructure owners, engineers, and contractors, allowing them to gain insights into groundbreaking research that is paving the way toward sustainable and resilient infrastructure.

Download or read book Alternative Materials in Road Construction written by Philip Thomas Sherwood and published by Thomas Telford. This book was released on 2001 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: With the landfill tax and the introduction of a tax on the use of primary aggregates, increasing financial pressure is now being exerted on highway engineers to provide the most economic alternatives to naturally-occurring roadmaking materials. Alternative materials in road construction: Second edition, provides practical guidance in the selection of substitute materials, including the economic and technical considerations of their use and advice on the benefits and pitfalls of each material. This fully revised second edition includes: Extensively re-written and updated sections on classification and sources Specifications of road making materials and environmental and economic considerations Enlarged sections on construction and demolition wastes to take account of the increasing concern at the depletion of natural resources and the much greater emphasis on recycling A new chapter on Government and EC Policy with respect to environmental damage and recycling Alternative materials in road construction: Second edition is divided into three parts. Part 1 discusses the demand and requirements of road making materials and the specifications that they have to meet if they are to give sa

Download or read book Proceedings of the Fifth International Conference of Transportation Research Group of India written by Dharamveer Singh and published by Springer Nature. This book was released on 2022-05-13 with total page 523 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book (in three volumes) comprises the proceedings of the Fifth Conference of Transportation Research Group of India (CTRG2019) focusing on emerging opportunities and challenges in the field of transportation of people and freight. The contents of the book include characterization of conventional and innovative pavement materials, operational effects of road geometry, user impact of multimodal transport projects, spatial analysis of travel patterns, socio-economic impacts of transport projects, analysis of transportation policy and planning for safety and security, technology-enabled models of mobility services, etc. This book will be beneficial to researchers, educators, practitioners and policymakers alike.

Download or read book Performance Related Tests on Recycled Materials for Sustainable Design of Pavement Systems written by Athar Saeed and published by . This book was released on 2011 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper provides recommendations for performance-related tests to select recycled materials to be used in pavement foundations (base/sub-base layers). The test protocol presented in this paper will help transportation agencies, pavement design engineers and construction industry professionals to mechanistically evaluate and select sources of recycled hot-mix asphalt and portland cement concrete materials and identify factors that contribute most to the longevity of layers using recycled pavement materials. Extensive literature review was conducted on the aggregate specifications in the United States and other countries to identify the protocols used to evaluate the suitability of virgin and recycled aggregates in base and sub-base layers. The test procedures, typically designed for virgin aggregates, were modified to account for the recycled materials in the aggregate mix. The test procedures were further evaluated on the basis of mechanical performance, accuracy, practicality, complexity, precision, and test cost. The performance of the developed aggregate evaluation systems was determined through testing and analysis of 12 aggregates with different lithology and known field performance history. These samples were selected from seven states with different seasonal frost cycles. The performance tests were conducted and modifications were made to the tests procedures to better understand the mechanical behavior of aggregate systems with recycled materials. This study revealed that shear strength, toughness, abrasion, durability, and frost susceptibility influence the performance of the unbound aggregate layers. Statistical analysis of the data showed that shear strength of the aggregate systems has the most impact on the performance of the unbound systems consisted of recycled materials.

Download or read book Geotechnical Properties of Recycled Concrete Aggregate in Pavement Sub Base Applications written by A. Arulrajah and published by . This book was released on 2012 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper presents a laboratory investigation of the geotechnical properties of recycled concrete aggregate (RCA). The properties of RCA were compared with state road authority requirements to assess its performance as a pavement sub-base material. The experimental programme included tests such as particle size distribution, modified Proctor compaction, particle density, water absorption, California bearing ratio (CBR), Los Angeles abrasion loss, pH, organic content, static triaxial, and repeated load triaxial tests. The Los Angeles abrasion loss tests indicated that the RCA is durable. CBR values were found to satisfy the local state road authority requirements for sub-base material. Repeated load triaxial tests established that the RCA would perform satisfactorily as a pavement sub-base material in the field. The results of the laboratory testing undertaken in this research indicated that RCA satisfied the criteria for use in pavement sub-base applications.

Download or read book Behavior of Recycled Asphalt Pavement and Recycled Concrete Aggregate as Unbound Road Base written by Ozlem Bozyurt and published by . This book was released on 2011 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: