Handbook of Induction Heating

Handbook of Induction Heating
Author: Valery Rudnev
Publisher: CRC Press
Total Pages: 816
Release: 2017-07-14
Genre: Science
ISBN: 1351643762

The second edition of the Handbook of Induction Heating reflects the number of substantial advances that have taken place over the last decade in theory, computer modeling, semi-conductor power supplies, and process technology of induction heating and induction heat treating. This edition continues to be a synthesis of information, discoveries, and technical insights that have been accumulated at Inductoheat Inc. With an emphasis on design and implementation, the newest edition of this seminal guide provides numerous case studies, ready-to-use tables, diagrams, rules-of-thumb, simplified formulas, and graphs for working professionals and students.

Semiconductor Laser Theory

Semiconductor Laser Theory
Author: Prasanta Kumar Basu
Publisher: CRC Press
Total Pages: 308
Release: 2015-07-16
Genre: Technology & Engineering
ISBN: 0415643317

This book provides the reader with a comprehensive background of semiconductor lasers. It covers their structure, materials, operating principles supported by proper theory, and light power output, as well as conversion efficiency and how frequently the devices can be switched on and off. It also discusses the different lasers working at different wavelengths, viz, ultraviolet, visible, infrared and mid and far infrared regions of electromagnetic spectrum along with proper structure, materials and theory.

Characterizing Short and Long Term Mixture Aging of a Full-scale and Non-trafficked Asphalt Test Section

Characterizing Short and Long Term Mixture Aging of a Full-scale and Non-trafficked Asphalt Test Section
Author: Braden T. Smith
Publisher:
Total Pages: 110
Release: 2017
Genre:
ISBN:

Ideally, asphalt pavements are designed to achieve sufficient stiffness prior to the application of traffic to resist rutting while also maintaining enough flexibility after years of service to minimize the amount of durability/brittleness related distresses (e.g. cracking and weathering). Multiple factors have caused an industry transition to mixes which are much more susceptible to crack, and durability related distresses are often the primary mechanism by which pavements fail. To restore a balance between rutting and durability distresses in asphalt pavements, the industry has started investigating balanced mix designs (BMDs) While mitigating only rutting or cracking behaviors is a straightforward exercise based on the collection of knowledge, simultaneously considering the two types of distresses is challenging considering that rutting is an early life distress and durability distresses are not typically observed until longer term aging has occurred. Mixture conditioning protocols to simulate field aging in conjunction with tests to fairly evaluate mixture integrity after conditioning are needed to scrutinize asphalt mixtures for durability related distresses during the mixture design phase. The current longer term conditioning protocol (R30) adopted by the American Association of State Highway and Transportation Officials (AASHTO) is not as severe as suggested when considering durability/brittleness (Isola et al. 2014; Yin et al. 2016; Cox et al. 2017). This dissertation’s primary objective is to provide guidance on asphalt mixture aging by contributing in four areas: 1) ensuring proper density measurement of field aged cores, 2) provide guidance on increased short term aging time effects in asphalt mixtures, 3) suggest improved mixture conditioning protocols to simulate longer term field aging, and 4) make suggestions for improving binder conditioning protocols to simulate longer term field aging. To these ends, a series of mixture and extracted binder tests were conducted on materials that were used to construct a full-scale test section in Columbus, MS that was monitored for aging for up to 5 after construction. The overall work presented provides simple recommendations or protocols which have the potential to improve the level of scrutiny that can be given to paving materials during the mix design phase and thus improve overall pavement performance.

Summary Report on Aging of Asphalt-aggregate Systems

Summary Report on Aging of Asphalt-aggregate Systems
Author: Chris A. Bell
Publisher:
Total Pages: 128
Release: 1989
Genre: Aggregates (Building materials)
ISBN:

This is a report on the state of the art of research on the phenomenon of the aging of asphalt-aggregate mixtures. Compared to research on the aging of asphalt cement, there has been little research on the aging of asphalt mixtures. Binder studies are considered as well as mixture sutdies, the relationship between laboratory aging tests and field performance, and the relationship between chemical composition and field performance. Recommendations are made for aging procedures which show promise for laboratory investigation. Test methods to evaluate aging are also considered. It is noted that extended heating procedures show the most promise for short-term aging and pressure oxidation and/or extended heating the most promise for long-term aging.

Effects of Mix, Aging, and Production Types on the I-FIT and IDEAL-CT Cracking Indices

Effects of Mix, Aging, and Production Types on the I-FIT and IDEAL-CT Cracking Indices
Author: Mustafa Mansour
Publisher:
Total Pages: 91
Release: 2020
Genre: Asphalt
ISBN:

Over the past few decades, the amount of recycled asphalt materials, such as reclaimed asphalt pavement (RAP), used in asphalt pavements has increased. The addition of RAP to an asphalt mixture is sought to reduce the costs related to the production of asphalt binder and quarrying for new aggregates. However, the addition of RAP increases the stiffness of an asphalt mixture making it more vulnerable to fatigue cracking. In recent years, two laboratory tests, namely the Illinois flexibility index test (I-FIT) and the indirect tensile asphalt cracking test (IDEAL-CT), have been proposed for use in mix design and quality control/quality assurance to characterize the fatigue cracking resistance of asphalt mixtures at intermediate temperatures. This study compared the cracking indices obtained using the two tests for four different asphalt mixtures (12.5 mm Superpave surface, 19 mm Superpave intermediate, Type 1 Marshall surface, and Type 2 Marshall intermediate), short-term and long-term aged specimens, as well as plant-produced laboratory-compacted (PPLC) and laboratory-produced laboratory-compacted (LPLC) specimens. As expected, the test results revealed significantly higher cracking indices for the short-term aged specimens than the long-term aged specimens. The post-peak slope was observed to be the most sensitive parameter to aging. The test results also showed higher cracking indices for the surface mixtures than the intermediate mixtures, with the Marshall mixes exhibiting higher cracking indices than the Superpave mixes. The same trend was obtained using the two laboratory tests. Finally, the test results revealed that there is a significant difference between the cracking indices for the plant-produced and laboratory-produced asphalt mixtures, with the plant-produced mixtures exhibiting higher cracking indices than the laboratory-produced mixtures.

Asphalt Pavements

Asphalt Pavements
Author: Y. Richard Kim
Publisher: CRC Press
Total Pages: 1966
Release: 2014-11-06
Genre: Technology & Engineering
ISBN: 1315736756

Asphalt Pavements contains the proceedings of the International Conference on Asphalt Pavements (Raleigh, North Carolina, USA, 1-5 June 2014), and discusses recent advances in theory and practice in asphalt materials and pavements. The contributions cover a wide range of topics:- Environmental protection and socio-economic impacts- Additives and mo

Short-term Laboratory Conditioning of Asphalt Mixtures

Short-term Laboratory Conditioning of Asphalt Mixtures
Author: David Newcomb
Publisher:
Total Pages: 196
Release: 2015
Genre: Asphalt
ISBN:

This report develops procedures and associated criteria for laboratory conditioning of asphalt mixtures to simulate short-term aging. The report presents proposed changes to the American Association of State Highway and Transportation Officials (AASHTO) R 30, Mixture Conditioning of Hot-Mix Asphalt (HMA), and a proposed AASHTO practice for conducting plant aging studies. The report will be of immediate interest to materials engineers in state highway agencies and the construction industry with responsibility for design and production of hot and warm mix asphalt.