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DUNE SAND-AGGREGATE MIXES AND DUNE SAND-SULFUR MIXES FOR ASPHALTIC CONCRETE PAVEMENTSFatani, Mohamed Noor Yaseen, 1944- January 1980 (has links)
No description available.
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Evolution of macro texture in asphalt pavement wearing course at an early ageTshephe, Otto Raikane. January 2013 (has links)
M. Tech. Civil Engineering. / Aims to assess the influence of the type of binder on the evolution of the macro texture in asphalt at an early age. The objective are to : 1. To assess the approach and methodology of French asphalt design method. 2. To establish the contributors to the reduction of skid resistance of asphalt. 3. Identify effective methods and develop guidelines for improving the surface drainage of asphalt with the use of tests from the laboratory. Asphaltic materials and factors under investigation include: pervious asphalt, continuously grade asphalt and various asphalt surface characteristics and correlation with the Tri-dim laser.
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Optimization of laboratory performance of hot mixed asphalt concrete with Costa Rican raw materialsCastro-Fernandez, Pedro Luis. January 2006 (has links)
Thesis (Ph. D.)--University of Nevada, Reno, 2006. / "May, 2006." Includes bibliographical references (leaves 183-187). Online version available on the World Wide Web.
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Measurement of absorption coefficient of road surfaces using impedance tube methodVissamraju, Krishnasudha, January 2005 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2005. / Abstract. Vita. Includes bibliographic references.
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Accelerated mix design of stabilized subgradesVeisi, Maryam, January 2008 (has links)
Thesis (M.S.)--University of Texas at El Paso, 2008. / Title from title screen. Vita. CD-ROM. Includes bibliographical references. Also available online.
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Evaluation of quality control parameters for Superpave hot mix asphaltAdams, Thomas W. January 2005 (has links)
Thesis (M.S.)--West Virginia University, 2005 / Title from document title page. Document formatted into pages; contains vii, 61 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 51).
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An evaluation of the Bailey method to predict voids in the mineral aggregateMason, Craig January 2006 (has links)
Thesis (M.S.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains viii, 75 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 61-62).
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Prediction of low temperature cracking of asphalt concrete mixtures with thermal stress restrained specimen test resultsKanerva, Hannele K. 21 June 1993 (has links)
Low temperature cracking is attributed to tensile stresses induced in an
asphalt concrete pavement that develop when the pavement is subjected to a cold
temperature. Cracking results in poor ride quality and a reduction in service life of
the pavement. Low temperature cracking has been predicted by regression
equations, mechanistic approaches and by simulation measurements. The purpose of
the study reported herein is to (1) evaluate the Thermal Stress Restrained Specimen
Test (TSRST) as an accelerated performance test to simulate low temperature
cracking of asphalt concrete mixtures and (2) develop a deterministic and
probabilistic model to predict low temperature cracking with TSRST results.
Construction histories, cracking observations and temperature data were
collected for five test roads in Alaska, Pennsylvania and Finland. A full scale and
fully controlled low temperature cracking test program was conducted at the U.S.
Army Cold Regions Research and Engineering Laboratory (USACRREL).
Specimens were fabricated in the laboratory with original asphalt cements and
aggregates from the test roads. In addition, asphalt concrete pavement specimens
were cut from the test sections. The TSRST results obtained for these samples were
correlated with the field observations. Based on a statistical analysis of the data, the
TSRST fracture temperature is associated with the field cracking temperature and
crack frequency for the test roads where mixture properties dominated low
temperature cracking. It was concluded that the TSRST can be used to simulate low
temperature cracking of asphalt concrete mixtures.
A deterministic and a probabilistic model were developed to predict crack
spacing as a function of time using the TSRST results, pavement thickness and bulk
density, pavement restraint conditions and air temperature. The affect of aging on
pavement properties was incorporated in the models by predicting the field aging
with Long Term Oven Aging (LTOA) treatment in the laboratory. The calculation
of the crack spacing is based on the theory that the pavement slab cracks when the
pavement temperature reaches the cracking temperature of the mixture and the slab
is fully restrained. The deterministic model predicts crack spacing with time
whereas the probabilistic model predicts crack spacing and its variation with time
and yields the reliability of the design with regard to a minimum acceptable crack
spacing criterion defined by road authorities.
The models were verified by comparing the predicted crack spacings for the
five test roads to the observed crack spacings. The probabilistic model is
recommended for use in predicting the low temperature cracking of asphalt concrete
mixtures. / Graduation date: 1994
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Selection and performance evaluation of a test method to assess thermal cracking resistance of asphalt-aggregate mixturesJung, Duhwoe 30 July 1993 (has links)
Thermal distress in asphalt concrete pavements is a widespread problem around
the world. Thermal cracking can be divided into two modes of distress: low
temperature cracking and thermal fatigue cracking. Low temperature cracking results
from extremely cold temperatures; thermal fatigue cracking results from daily
temperature cycles.
Low temperature cracking is attributed to tensile stresses induced in the asphalt
concrete pavement as the temperature drops to an extremely low temperature. If the
pavement is cooled, tensile stresses develop as a result of the pavement's tendency to
contract. The friction between the pavement and the base layer resists the contraction.
If the tensile stress equals the strength of the mixture at that temperature, a micro-crack
develops at the surface of the pavement. Under repeated temperature cycles, the
crack penetrates the full depth and across the asphalt concrete layer.
The thermal stress restrained specimen test (TSRST) was identified as an
accelerated laboratory test to evaluate the thermal cracking resistance of asphalt concrete mixtures. The TSRST system developed at OSU includes a load system, data control/acquisition system and software, temperature control system, and specimen alignment stand. The overall system is controlled by a personal computer.
A TSRST is conducted by cooling an asphalt concrete specimen at a specified rate while monitoring the specimen at constant length. A typical thermally-induced stress curve is divided into two parts: relaxation and non-relaxation. The temperature at which the curve is divided into two parts is termed the transition temperature. The temperature at fracture is termed the fracture temperature and the maximum stress is the fracture strength.
An extensive number of TSRSTs over a wide range of conditions were performed to investigate the thermal cracking resistance of asphalt concrete mixtures. The TSRST results provided a very strong indication of low temperature cracking resistance for all mixtures considered. A ranking of mixtures for low temperature cracking resistance based on the TSRST fracture temperature was in excellent agreement with a ranking based on the physical properties of the asphalt cements.
It is highly recommended that the TSRST be used in mix evaluation to identify low temperature cracking resistance of asphalt concrete mixtures. The TSRST showed very promising results regarding the effect of all variables which are currently considered to affect the low temperature cracking of mixtures. The variables considered to have significant affect on the low temperature cracking resistance of mixtures in this study include asphalt type, aggregate type, degree of aging, cooling
rate, and stress relaxation. / Graduation date: 1994
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Development of the simplified method to evaluate dynamic mechanical analysis data on asphalt-aggregate mixturesAb-Wahab, Yunus Bin 16 February 1993 (has links)
Testing of asphalt binders and asphalt-aggregate mixtures using dynamic
mechanical analysis is becoming popular with improvements in high-speed
computers, precision equipment, and computer software. Researchers are trying
to describe the behavior of asphalt binders and asphalt-aggregate mixtures in
terms of their time- and temperature-dependent linear viscoelastic behavior.
The objectives of this thesis were to develop a simplified pneumatic test to
perform dynamic mechanical analysis (DMA), to evaluate the performance of the
pneumatic and hydraulic test systems using the computer software developed to
perform DMA tests, and, to develop a simplified method to evaluate the
experimental data obtained from DMA tests on aged asphalt-aggregate mixtures.
A simplified pneumatic test system was developed to perform DMA.
Computer software was also developed to perform DMA testing on both the
simplified pneumatic and hydraulic test systems. DMA was performed on both
test systems to compare their performance, and on aged asphalt-aggregate
mixtures to evaluate the application of the simplified method.
The results from the pneumatic and hydraulic test systems show that there
is about a 20 percent difference in the complex modulus, especially at high loading
frequencies. This is due to the compressibility of the air used in the pneumatic
test system. The compressibility of air is greater at warmer temperatures than at
cooler temperatures. Therefore, the application of the pneumatic test system to
perform dynamic testing should be limited to low frequencies ( < 2 Hz), low
temperatures ( < 25°C), and low load ( < 454 kg (1000 lbs.)) applications unless
a modification can be made to increase the pneumatic cylinder's response time to
match the hydraulic cylinder's response time.
The simplified analysis method developed in this thesis divides the DMA
results into four complex modulus and five phase angle parameters. These
parameters describe the shapes of the master stiffness and phase angle curves and
distinguished between the different asphalt-aggregate mixtures and the aging
methods performed on the aged asphalt-aggregate mixtures. The phase angle
parameters were reduced into two variables, peak frequency and peak angle,
which vary with the aging of each asphalt-aggregate mixture. The peak frequency
and peak angle decrease as the aging severity increases and the change of peak
frequency and peak angle vary with the asphalt-aggregate mixture and aging
treatment. Therefore, the complex modulus parameters and peak frequency and
peak angle may be good indicators to describe how a master curve's shape varies
with asphalt, aggregate, and aging type. / Graduation date: 1993
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