Download or read book Assessing Cryogenic Testing of Aggregates for Concrete Pavements written by Charles J. Korhonen and published by . This book was released on 1995 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessing Cryogenic Testing of Aggregate for Concrete Pavements written by and published by . This book was released on 1995 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Damage to concrete pavements caused by freeze-thaw deterioration of concrete aggregate remains a serious problem. Current tests for determining an aggregate's freeze-thaw durability can take up to 70 days to perform and results from these tests don't always correlate well with field performance. A rapid test for freeze-thaw durability that would accurately predict field service would be a valuable tool for providing durable concrete. Cycling aggregate 10 times between liquid nitrogen and hot water proved useful as a tool to rule out frost-susceptible aggregate. Pore size distribution measurements reveal pore sizes that are critical to freeze-thaw durability. Aggregates with more than 75% of their measurable pore volume between pore diameters of 0.01 and 5 micrometers or with more than 95% of their measurable pore volume smaller than 5 micrometers were susceptible to frost damage. Thus a new freeze-thaw test for aggregates might employ the cryogenic test to screen out all frost- susceptible aggregate and pore size measurement classify the rest. This new test procedure offers results much sooner than current standard test procedures. Further study is needed to refine this method for general use. (MM).
Download or read book Special Report written by and published by . This book was released on 1995 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Monthly Catalog of United States Government Publications written by and published by . This book was released on 1971 with total page 1388 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aggregate Tests for Portland Cement Concrete Pavements written by Amir Naoum Hanna and published by . This book was released on 2003 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: "This digest summarizes the findings from NCHRP Project 4-20C, 'Aggregate Tests Related to Performance of Portland cement concrete Pavements: State of the Knowledge.' It was prepared by Dr. Amir N. Hanna ... from the contractor's final report authored by Dr. Kevin J. Folliard and Mr. Kurt D. Smith ..."--Page 1
Download or read book Evaluation of Recycled Aggregates Test Section Performance written by Farhad Reza and published by . This book was released on 2017 with total page 195 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need to consider sustainability in design dictates that materials should be recycled and reused whenever possible. The Minnesota Department of Transportation (MnDOT) is quite progressive in allowing the use of recycled aggregates in new construction. While the use of recycled concrete aggregate (RCA) in the base course of new pavements is quite common in Minnesota and many other states, it is rarely used in the concrete pavement itself. In fact, Minnesota was one of the few states to build multiple trial projects and has one of the largest number of concrete pavements constructed using the RCA in the concrete itself. The performance of those pavements, most of which are still in service, has never been formally evaluated against similar conventional concrete pavements. This prompted the current research study. Additional objectives were to assess the current state of practice across the nation, conduct experimental investigations using RCA in concrete, assess the sustainability and in particular the economics of using RCA in concrete, and finally to provide some recommendations for guidelines on using RCA in concrete. It has been shown by the authors and other researchers that it is possible to create strong and durable concrete mixtures using RCA as coarse aggregate in volume replacement levels of natural coarse aggregate up to 100%.
Download or read book Evaluation of Portland Cement Concrete Coefficient of Thermal Expansion Test Protocol and the Impact of CTE on Performance of Jointed Concrete Pavements written by Shervin Jahangirnejad and published by . This book was released on 2009 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Repeated Load Testing for Primary Evaluation of Recycled Concrete Aggregate in Pavements written by Alaa Gabr and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book NBS Special Publication written by and published by . This book was released on 1971 with total page 1064 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 700 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book A Guide to Evaluating Thermal Effects in Concrete Pavements written by Per Just Andersen and published by . This book was released on 1993 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report describes the use of tables developed to help determine problems that may result from early thermal effects in concrete. The thermal behavior of concrete can be estimated from a knowledge of concrete temperature, air temperature, type of cement, and content of cement in the mixture. The thermal effects tables can be used to predict whether too high a temperature will be reached in the pavement; whether early thermal cracking will result from larger differences between the temperature of the concrete slab and the temperature of either the air or the base; or whether there is a risk of early cracking of the concrete. Examples of the use of the table are given along with guidelines for avoiding undesirable thermal effects.
Download or read book Evaluation of Tests for Repair Materials Used in Concrete Pavements written by Chandler and published by Thomas Telford Publishing. This book was released on 1998-12-31 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Rapid Thermal Analysis Technique for Aggregates in Portland Cement Concrete written by Mohamed Nagib Abou-Zeid and published by . This book was released on 1996 with total page 92 pages. Available in PDF, EPUB and Kindle. Book excerpt: Durability of course aggregate has a major impact on the durability of Portland cement concrete. Over the past years, there has been an increasing interest in developing and improving test techniques that provide a faster accurate durability assessment which ultimately leads to a better prediction of pavement performance. Thermogravimetric analysis (TGA) is a relatively rapid technique that has shown good potential for use in the analysis of carbonate aggregates. In this work, thermogravimetric technique was used to analyze 31 limestone and two dolomite aggregates, The specimens were heated to temperatures above 1000 C (1832 F) using two rates of temperature increase. The weight loss and the change in weight loss as a function of temperature were recorded. The data was acquired by a data acquisition system and later transferred to a microcomputer for analysis.
Download or read book Government Reports Announcements Index written by and published by . This book was released on 1995-11 with total page 904 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A New Methodology for Assessing the Frost Resistance of Concrete Aggregates written by Amir Koubaa and published by . This book was released on 1997 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Aggregate Freeze thaw Testing and D cracking Field Performance written by Heather A. K. McLeod and published by . This book was released on 2014 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: Premature deterioration of concrete pavement due to D-cracking has been a problem in Kansas since the 1930s. Kansas geology includes mineable limestone coarse aggregates with variable durability in the eastern portion of the state. Due to this variability and historically poor D-cracking field performance, the Kansas DOT initiated intensive identification and tracking of individual mined beds, as well as frequent durability testing during production in the 1980s. D-cracking field performance of concrete pavements containing limestone coarse aggregates was investigated in 2010- 2012. Results of this investigation indicate that the rate of D-cracking decreased, but the minimum rate of D-cracking presence in concrete pavements is more than 30%. In reaction to these results, KDOT implemented changes aimed at mitigating the risk of D-cracking. Implementation actions included increasing the number of freeze-thaw cycles for aggregate in concrete prisms from 300 to 660 cycles, freeze-thaw testing of all aggregate types (not just limestone) in concrete, focusing aggregate sampling at the point of concrete production, and including an "acceptable field-performance history" criterion for concrete aggregates. Ongoing research is being conducted to develop new methods to identify durable aggregates and faster testing techniques.
Download or read book An Index of U S Voluntary Engineering Standards written by William J. Slattery and published by . This book was released on 1971 with total page 1016 pages. Available in PDF, EPUB and Kindle. Book excerpt:
