[PDF] Prc 522 23 Pervious Concrete Report eBook

Author : ACI Committee 522
Publisher :
Page : 38 pages
File Size : 24,22 MB
Release : 2010
Category : Lightweight concrete
ISBN : 9780870313646

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"This report provides technical information on pervious concrete's application, design methods, materials, properties, mixture proportioning, construction methods, testing, and inspection. The term 'pervious concrete' typically describes a near-zero-slump, open-graded material consisting of portland cement, coarse aggregate, little or no fine aggregate, admixtures, and water." [p. 1]

Author : William B. Denison
Publisher :
Page : 10 pages
File Size : 13,35 MB
Release : 2012
Category : Curing
ISBN :

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Titan Virginia Ready Mix (TVRM) sponsored a study involving field and laboratory testing on numerous placement segments of the 4700 yd3 (8 acres) of pervious pavement supplied to the Prime Outlet Mall project in Williamsburg, Virginia, 2008. The intent of the study was to gather a statistically sufficient quantity of test data of plastic and hardened properties using ASTM test standards from a project large in square footage to provide such data. The TVRM approach involved representative sampling, plastic and hardened density testing, void % determination, thickness measurements, and compressive and flexural strength testing. The hardened test specimens were obtained by coring and sawing from precast panels cast onsite during pavement production. The test panels measuring 3 ft x 3 ft x 6 in. in depth had supporting bottoms and was cast from composite samples obtained at the project site. The test panels were cast and cured in the same manner as the pervious pavement, one test panel for every 150 to 200 yd3. The test panels were cured a minimum of 7 days to promote the necessary aggregate/ cement paste bond development as is referenced in ACI 522.1-08 [ACI 522-1, "Specification for Pervious Concrete Pavement," American Concrete Institute, Farmington Hills, MI, 2008]. Once the curing was complete the pervious test panels were cushioned, and transported to the TVRM laboratory for further curing and hardened strength and density testing. The TVRM objective was to compile enough raw data with consistent test results to help designers and specifiers in designing for future pervious projects.

Author :
Publisher :
Page : 79 pages
File Size : 12,62 MB
Release : 2007
Category : Pavements, Concrete
ISBN :

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Portland Cement Pervious Concrete (PCPC) has an excellent performance history in the Southeastern U.S., but until recently has seen little use in environments with significant freeze-thaw cycles. Therefore, assessment of actual field performance is important. This project documents field observations, and nondestructive testing results of PCPC sites located in the states of Ohio, Kentucky, Indiana, Colorado, and Pennsylvania. PCPC is most often used as a pavement for parking lots. Field performance depends on the quality of the mixture as well as proper control of construction and curing. In addition to field observations and nondestructive testing, laboratory testing was performed on cores removed from some of the test sites. Generally, the PCPC installations evaluated have performed well in freeze-thaw environments, with little maintenance required. Construction, use, and maintenance information was obtained during the site visits. The field investigation plan encompassed a thorough visual inspection for signs of distress, two types of surface infiltration measurements, and ultrasonic pulse velocity (UPV) testing at the Ohio, Kentucky, and Indiana sites. At the Colorado and Pennsylvania sites, only one type of surface infiltration test was made. Visual inspection documented cracking and surface raveling, as well as areas that appeared to be clogged. One type of field infiltration test, developed during this research project, used the time to drain a 4 by 8 inch plastic cylinder through a 3/4 inch hole down into the pavement. The second test was used to identify whether pavements required maintenance. The UPV was used in indirect transmission mode, because only the surface of the pavement was accessible. At six of the sites, it was possible to extract cores for laboratory testing. The cores were brought back to the laboratory and tested for void ratio, hydraulic conductivity, and direct transmission UPV. Direct transmission is considered to be more reliable than indirect transmission for UPV. Once these tests were completed, some of the specimens were tested for compressive or splitting tensile strength. Some of the cores were cut into top and bottom specimens, to compare the properties through the pavement thickness. The data are recorded in tables and plots. Significant differences were observed between cores from pavements that used gravel and crushed limestone coarse aggregates. The use of gravel as a coarse aggregate may facilitate more effective and uniform compaction. The laboratory hydraulic conductivity results were plotted against the field drainage times, so that in the future the field test may be used to estimate PCPC infiltration capability. The installations have not shown any signs of freeze-thaw damage. Some pavements have had surface raveling, which generally stops after a few months of use. Saw cut joints had less raveling than tooled joints. A few have cracks, which may be attributed to overloading or long spaces between joints. Some of the pavements had very poor infiltration capability due to improper installation. Most of the installations are performing well, but it is also true that many in the area are relatively new. Therefore, they should be examined again in the future, probably at 5 and 10 years from the publication of this report. This report serves as a benchmark of the pavement condition observed at the time of this study.

Author : Ryan J. Rohne
Publisher :
Page : 64 pages
File Size : 36,10 MB
Release : 2009
Category : Pavements, Concrete
ISBN :

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This report evaluates the third year performance of the pervious concrete test Cell 64 located in the parking lot/driveway on the south side of MnROAD's pole barn. In this report, a device and procedure to evaluate the drainability of pervious concrete and a threshold for clogging was developed. In addition, the condition of the test cell was determined by Schmidt hammer measurements and distress mapping using the Mn/DOT Pavement Distress Identification Manual. Watermark/thermocouple data was also recorded to measure freeze-thaw cycles. The number of freeze-thaw cycles at discrete depths in the pavement was then compared to impervious concrete test cells at MnROAD. The Mn/DOT and Cemstone petrographic reports on cores that had been taken 4.5 months after construction are also included, although they were outlined in previous reports. It was found that the pervious concrete of Cell 64 experienced less freeze-thaw cycles than impermeable concrete pavements of similar thickness. The main change in surface distress from the first year to the third year of service was the presence of a longitudinal crack that extended the entire cell length and raveling of the top layer of concrete. Initiating at the pole barn at a joint in the concrete curb, the crack could have propagated the length of Cell 64 due to Falling Weight Deflectometer (FWD), traffic, or thermal loading. Knowledge of pervious concrete will be greatly expanded with the study of newly constructed test cells. These cells are Cell 85, Portland Cement Concrete (PCC) pervious on sand and 89, PCC pervious on clay on the MnROAD Low Volume Road.

Author : Norbert Delatte
Publisher : CRC Press
Page : 389 pages
File Size : 45,6 MB
Release : 2007-09-12
Category : Technology & Engineering
ISBN : 0203961080

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Addressing the interactions between the different design and construction variables and techniques this book illustrates best practices for constructing economical, long life concrete pavements. The book proceeds in much the same way as a pavement construction project. First, different alternatives for concrete pavement solutions are outlined. The desired performance and behaviour parameters are identified. Next, appropriate materials are outlined and the most suitable concrete proportions determined. The design can be completed, and then the necessary construction steps for translating the design into a durable facility are carried out. Although the focus reflects highways as the most common application, special features of airport, industrial, and light duty pavements are also addressed. Use is made of modeling and performance tools such as HIPERPAV and LTPP to illustrate behavior and performance, along with some case studies. As concrete pavements are more complex than they seem, and the costs of mistakes or of over-design can be high, this is a valuable book for engineers in both the public and private sectors.

Author : Ross Garnaut
Publisher : ANU E Press
Page : 486 pages
File Size : 36,18 MB
Release : 2009-07-01
Category : Political Science
ISBN : 1921536977

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The world and China's place in it have been transformed over the past year. The pressures for change have come from the most severe global financial crisis ever. The crisis has accelerated China's emergence as a great power. But China and its global partners have yet to think or work through the consequences of its new position for the governance of world affairs. China's New Place in a World in Crisis discusses and provides in-depth analysis of the following questions. How have China's growth prospects been affected by the global crisis? How will the crisis and China's response to it impact China's major domestic issues, such as industrialisation, urbanisation and the reform of the state-owned sector of the economy? How will the crisis and the international community's response to it affect the rapidly emerging new international order? What will be China's, and other major developing countries', new role? Can China and the world find a way of breaking the nexus between economic growth and environmental sustainability - especially on the issue of climate change?