Development of Nondestructive Methods for Measurement of Slab Thickness and Modulus of Rupture in Concrete Pavements PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Development of Nondestructive Methods for Measurement of Slab Thickness and Modulus of Rupture in Concrete Pavements PDF full book. Access full book title Development of Nondestructive Methods for Measurement of Slab Thickness and Modulus of Rupture in Concrete Pavements by John S. Popovics. Download full books in PDF and EPUB format.
Author: John S. Popovics
Publisher:
ISBN:
Category : Nondestructive testing
Languages : en
Pages : 80
Get Book Here
Book Description
This report describes work to develop non-destructive testing methods for concrete pavements. Two methods, for pavement thickness and in-place strength estimation, respectively, were developed and evaluated. The thickness estimation method is based on a new hybrid approach that combines frequency domain (impact-echo) and time domain (seismic) data. This new method makes use of a fuller understanding of the dynamic wave phenomenon, which was developed during the course of the work. The effects of material property gradients (due to aggregate segregation and moisture variation) through the slab thickness are compensated for in the method. A field testing method is proposed, described, and experimentally verified. Verification tests carried out on full-scale concrete slabs cast on granular base show that the new method provides more accurate thickness estimates than those obtained by the standard impact-echo procedure. On average, the error between predicted thickness and actual thickness determined by cores is less than 6 mm, although some individual estimates exceed this error value. However, the new method does not work on concrete over asphalt or cement-treated base (which accounts for most concrete pavements) or on full-depth asphalt concrete pavements. The in-place strength estimation method is based on ultrasonic surface wave measurements. A field test method is proposed, described, and experimentally verified. Verification tests carried out on a range of concrete mixtures with varying aggregate type and cementitious material, all of which satisfy the requirements of "A3" concrete as specified by the Virginia Department of Transportation. Two data analysis procedures are proposed. One procedure predicts flexural strength within 50 psi of actual strength determined by direct strength measurement of beams, although the procedure requires 1-day strength and ultrasonic values to be known. The second procedure is more flexible but provides strength estimates with lower accuracy. Field tests, which were carried out at two pavement sites in Virginia, are reported for both methods. Finally, a detailed description of the required testing equipment and experimental and analytical procedures for both methods are included in the Appendix. Cost savings from implementing the methods are not obvious, since the methods cannot be used to measure the thickness of most concrete pavements for acceptance and payment. The methods can be used to nondestructively evaluate the modulus of rupture of pavements for analysis purposes, but savings would depend on the nature of the analysis.
Author: John S. Popovics
Publisher:
ISBN:
Category : Nondestructive testing
Languages : en
Pages : 80
Get Book Here
Book Description
This report describes work to develop non-destructive testing methods for concrete pavements. Two methods, for pavement thickness and in-place strength estimation, respectively, were developed and evaluated. The thickness estimation method is based on a new hybrid approach that combines frequency domain (impact-echo) and time domain (seismic) data. This new method makes use of a fuller understanding of the dynamic wave phenomenon, which was developed during the course of the work. The effects of material property gradients (due to aggregate segregation and moisture variation) through the slab thickness are compensated for in the method. A field testing method is proposed, described, and experimentally verified. Verification tests carried out on full-scale concrete slabs cast on granular base show that the new method provides more accurate thickness estimates than those obtained by the standard impact-echo procedure. On average, the error between predicted thickness and actual thickness determined by cores is less than 6 mm, although some individual estimates exceed this error value. However, the new method does not work on concrete over asphalt or cement-treated base (which accounts for most concrete pavements) or on full-depth asphalt concrete pavements. The in-place strength estimation method is based on ultrasonic surface wave measurements. A field test method is proposed, described, and experimentally verified. Verification tests carried out on a range of concrete mixtures with varying aggregate type and cementitious material, all of which satisfy the requirements of "A3" concrete as specified by the Virginia Department of Transportation. Two data analysis procedures are proposed. One procedure predicts flexural strength within 50 psi of actual strength determined by direct strength measurement of beams, although the procedure requires 1-day strength and ultrasonic values to be known. The second procedure is more flexible but provides strength estimates with lower accuracy. Field tests, which were carried out at two pavement sites in Virginia, are reported for both methods. Finally, a detailed description of the required testing equipment and experimental and analytical procedures for both methods are included in the Appendix. Cost savings from implementing the methods are not obvious, since the methods cannot be used to measure the thickness of most concrete pavements for acceptance and payment. The methods can be used to nondestructively evaluate the modulus of rupture of pavements for analysis purposes, but savings would depend on the nature of the analysis.
Author: S. D. Howkins
Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 106
Get Book Here
Book Description
The feasibility is investigated of various acoustic (sonic), nuclear, and electrical techniques for nondestructive measurement of Portland cement and bituminous concrete pavement thickness both during and after construction. Recommendations are made for equipment development and field testing of three specific methods that could potentially result in such measurements with the desired degree of speed and accuracy.
Author: ASTM Committee D-18 on Soil and Rock. Subcommittee D-4 on Road and Paving Materials
Publisher: ASTM International
ISBN: 9780803118652
Category : Technology & Engineering
Languages : en
Pages : 546
Get Book Here
Book Description
The proceedings of June 1993 international symposium held in Atlanta, Georgia, called specifically to develop and standardized evaluation procedures for non-destructive methods of testing pavements. The 29 papers discuss analytical models and techniques, measurement and calculation techniques in the field and laboratory, problems and errors associated with backcalculation methods and design parameters, and testing for other pavement uses. Also includes a history of the quest for a standard and the status of that effort. Reproduced from typescripts. Annotation copyright by Book News, Inc., Portland, OR
Author: Albert Jasper Bush
Publisher: ASTM International
ISBN: 0803112602
Category : Kaldırımlar-Deneme
Languages : en
Pages : 701
Get Book Here
Book Description
Author: Gerardo G. Clemeña
Publisher:
ISBN:
Category : Pavements, Concrete
Languages : en
Pages : 42
Get Book Here
Book Description
The nondestructive impact-echo (IE) method offers a simple means for introducing compressional stress waves into a concrete element or slab and measuring the resonance frequencies associated with the reflections of the waves from any internal voids and the bottom of the slab. It is relatively effective for detecting internal voids or delaminations in concrete, which is the application for which it was developed. It may also be possible to use the method for indirect measurement of the thickness of a slab if the wave propagation velocity in the concrete is known. This study was conducted to determine whether the IE method, by itself, could replace the use of coring for quality-assurance measurements of the thickness of concrete slabs in newly built pavements. The results from tests conducted on three pavemems indicated that the wave velocity varied so much, not only between pavements but also within a pavement, that unacceptable errors can result when an average velocity is determined (through limited coring) for a pavemem and subsequently assumed for the entire pavement. To reduce the error to an acceptable level, the wave velocity at any test location must be measured to within an acceptable accuracy by another independent method. In pursuit of this approach, an indirect-transmission procedure based on ultrasonic (UT) measurement was incorporated and tested. This combined IE/UT procedure was able to measure thickness with absolute errors of 5 mm in one pavement and 7 mm in another, at a 90% probability. These results can be considered encouraging since the current procedure requires that the length of a core reported to the nearest 3 mm be the average of several measurements around the core and, in some cores, these measurements can have a spread of as much as 13 mm. In addition, it is expected that these errors can be reduced easily with the use of a transducer with a smaller contact face that would be less sensitive to roughness on the surface of grooved concrete pavements.
Author:
Publisher:
ISBN:
Category : Nondestructive testing
Languages : en
Pages : 46
Get Book Here
Book Description
Author: Kenneth R. Maser
Publisher:
ISBN:
Category : Nondestructive testing
Languages : en
Pages : 110
Get Book Here
Book Description
Author: National Research Council (U.S.). Transportation Research Board
Publisher:
ISBN:
Category : Pavements, Concrete
Languages : en
Pages : 68
Get Book Here
Book Description
Author: Gerardo G. Clemeña
Publisher:
ISBN:
Category : Ground penetrating radar
Languages : en
Pages : 44
Get Book Here
Book Description
Previous microwave reflection measurements made on simple, unreinforced concrete blocks have shown that the transit time of a microwave through concrete is linearly related to its thickness. In this study measurements were conducted on concrete slabs that were built to simulate pavements and on an actual continuously reinforced concrete pavement to determine whether this type of rapid nondestructive measurement could be used in lieu of coring in the inspection of newly built concrete pavements for compliance with slab thickness specifications. It was found that reflections from the bottom of a concrete pavement slab may often be too weak and difficult to identify in a radar profile; therefore, the transit time of a microwave through reinforced concrete slab would often be difficult to measure with reasonable accuracy. The results obtained with radar measurements made on simulated pavement slabs showed that radar was only able to indicate whether a slab is too thin (i.e., less than 8 in); but those measurements made on an actual pavement yielded reasonably good agreement between the thickness determined by coring and those determined by reflection measurements in conjunction with a calibration procedure. Based on these mixed results, it would be difficult to predict how reliable radar would be for precise quantitative measurement of slab thickness of a particular pavement until an actual radar scan of the pavement has been conducted. If the reflection from the bottom of the slab appeared to be identifiable, then the calibration procedure could be used to determine the slab thickness for the entire pavement. Otherwise, radar can be used at least as a screening tool to spot areas in the pavement that appear to be to thin. These areas would then be cored to verify the radar readings.
Author:
Publisher:
ISBN:
Category : Concrete
Languages : en
Pages : 264
Get Book Here
Book Description
This report represents nearly 6 years of collaboration among Federal Highway Administration (FHWA), State, and American Concrete Pavement Association (ACPA) engineers on the subject of Fastrack Concrete Paving. As an outgrowth of activities begun in 1986 in Storm Lake, Iowa, a Technical Working Group (TWG) assembled under the auspices of the FHWA's Special Project 201. Since the first meeting in Alexandria, Virginia, in 1988, the TWG has cooperated to construct pilot projects, test concrete material with the FHWA's mobile laboratory, sponsor workshops and conferences nationwide, simulate exercises on urban project designs, complete ACPA's Technical Bulletin on Fastrack, and support follow-on research. This report formally completes activities carried out under SP-201. It presents key information on opening-to-traffic criteria and pavement slab temperature management. It includes a summary of key projects built around the country in the last 6 years. It also includes a copy of ACPA's new bulletin and closes with reprints of several technical reports that may be of interest to the reader.
