Non-Destructive Characterization of Asphalt Concrete Mixtures Through Resonant Column Testing 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 Non-Destructive Characterization of Asphalt Concrete Mixtures Through Resonant Column Testing PDF full book. Access full book title Non-Destructive Characterization of Asphalt Concrete Mixtures Through Resonant Column Testing by Pezhouhan Tavassoti Kheiry. Download full books in PDF and EPUB format.
Author: Pezhouhan Tavassoti Kheiry
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Asphalt concrete is a multiphase viscoelastic composite material; hence its mechanical properties change with frequency of the applied loads and the temperature. In many of the design tools such as the Mechanistic Empirical Pavement Design Guide (MEPDG), changes in dynamic modulus as a function of the loading frequency is the primary input. There are very limited testing devices that can directly measure the shear modulus of asphalt concrete. Most of the available devices for asphalt concrete testing are limited to a maximum loading frequency of 33 Hz. However, devices that are capable of exerting loads at higher frequencies are generally limited with respect to the maximum attainable strains. Treating an asphaltic mix as a thermo-rheologically simple material makes it possible to extrapolate its viscoelastic behavior from the low frequency to the high frequency ends through a modulus master-curve. However, such extrapolations are not always accurate and can result in significant errors in pavement design and performance prediction. In this dissertation, a conventional soils testing Resonant Column (RC) apparatus is retrofitted to test stiffer materials such as asphalt concrete at a range of temperatures and strains. Through the proposed RC test, the frequency dependent modulus of asphalt concrete at frequencies considerably higher than those attainable by the available devices, i.e. up to 300 Hz, and at strain levels comparable to the conventional modulus tests (about 100 microstrains) were measured. A set of dynamic modulus (DM) tests were performed on both the full-size and the proposed small-size specimens. It was confirmed that the small specimens exhibit the same properties as the full-size specimens. Non-destructiveness of the RC testing of asphalt concrete was also confirmed by investigating the repeatability of RC tests at each temperature, the reproducibility of the same results after one complete set of temperature-frequency sweep tests, and the modulus changes from Impact Resonance (IR) tests. Thus, the same specimen can be used for conducting multiple tests at different temperatures. Finally, RC technique was successfully used to characterize a wide range of asphalt concrete technologies including: conventional Hot Mix Asphalt (HMA), Warm Mix Asphalt (WMA), high Reclaimed Asphalt Pavements (RAP) content, and high Recycled Asphalt Shingles (RAS) mixes. Results indicate that the conventional modulus master curve underpredicts the actual modulus at higher frequencies. Therefore, the proposed power-form modulus-frequency functions are recommended in this dissertation to be used along with a variable Poissons ratio to achieve a better prediction, when an indirect calculation of shear modulus of asphalt concrete is needed. It was concluded that RC test can non-destructively characterize different asphalt concrete technologies at a wide range of temperatures. The RC test provides useful insights about the high frequency modulus and damping of asphalt concrete mixes.
Author: Pezhouhan Tavassoti Kheiry
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Asphalt concrete is a multiphase viscoelastic composite material; hence its mechanical properties change with frequency of the applied loads and the temperature. In many of the design tools such as the Mechanistic Empirical Pavement Design Guide (MEPDG), changes in dynamic modulus as a function of the loading frequency is the primary input. There are very limited testing devices that can directly measure the shear modulus of asphalt concrete. Most of the available devices for asphalt concrete testing are limited to a maximum loading frequency of 33 Hz. However, devices that are capable of exerting loads at higher frequencies are generally limited with respect to the maximum attainable strains. Treating an asphaltic mix as a thermo-rheologically simple material makes it possible to extrapolate its viscoelastic behavior from the low frequency to the high frequency ends through a modulus master-curve. However, such extrapolations are not always accurate and can result in significant errors in pavement design and performance prediction. In this dissertation, a conventional soils testing Resonant Column (RC) apparatus is retrofitted to test stiffer materials such as asphalt concrete at a range of temperatures and strains. Through the proposed RC test, the frequency dependent modulus of asphalt concrete at frequencies considerably higher than those attainable by the available devices, i.e. up to 300 Hz, and at strain levels comparable to the conventional modulus tests (about 100 microstrains) were measured. A set of dynamic modulus (DM) tests were performed on both the full-size and the proposed small-size specimens. It was confirmed that the small specimens exhibit the same properties as the full-size specimens. Non-destructiveness of the RC testing of asphalt concrete was also confirmed by investigating the repeatability of RC tests at each temperature, the reproducibility of the same results after one complete set of temperature-frequency sweep tests, and the modulus changes from Impact Resonance (IR) tests. Thus, the same specimen can be used for conducting multiple tests at different temperatures. Finally, RC technique was successfully used to characterize a wide range of asphalt concrete technologies including: conventional Hot Mix Asphalt (HMA), Warm Mix Asphalt (WMA), high Reclaimed Asphalt Pavements (RAP) content, and high Recycled Asphalt Shingles (RAS) mixes. Results indicate that the conventional modulus master curve underpredicts the actual modulus at higher frequencies. Therefore, the proposed power-form modulus-frequency functions are recommended in this dissertation to be used along with a variable Poissons ratio to achieve a better prediction, when an indirect calculation of shear modulus of asphalt concrete is needed. It was concluded that RC test can non-destructively characterize different asphalt concrete technologies at a wide range of temperatures. The RC test provides useful insights about the high frequency modulus and damping of asphalt concrete mixes.
Author: Ilker Boz
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Characterization of asphalt concrete is of paramount importance for the sound structural design and analysis of flexible pavements. Of equal importance is the availability of test methods that can provide an accurate and reliable measure of the required engineering properties of the material. For routine applications in material characterization, selected test methods should be reliable, simple, quick, repeatable, and cost eective. The use of nondestructive test (NDT) methods has proven to provide such characterization capabilities. Among those methods, the impact resonance (IR) test is a vibration based NDT method, and has been increasingly used for asphalt concrete evaluation and characterization in the past two decades. The majority of studies regarding the IR test in asphalt concrete applications have been focused on comparison of the IR test moduli with the moduli obtained from conventional asphalt concrete dynamic modulus tests and the predictive equations. In this dissertation, the IR test was utilized to characterize the properties of asphalt concrete mixtures and recycled asphalt pavement (RAP) binder through mixture testing at a range of temperatures. To this eect, several independent studies were conducted.The second order equation of motion assumption in rheological modeling of the IR test response was evaluated for asphalt concrete testing. A set of asphalt concrete specimens was tested with the IR test, and the obtained signals at a range of temperatures were evaluated by means of the Hankel matrix method. The results showed that the assumption is violated for asphalt concrete testing, especially at high temperatures, mainly due to the presence of noise in the obtained response. However, the Hankel method was employed to filter out the noise. It was seen that the assumption could be employed for asphalt concrete at a range of temperatures including high temperatures, provided that the filtering is performed on the obtained signal. The results also showed that the employed filtering procedure produced improvements for the IR test material dependent responses, resonant frequency and especially damping ratio calculations.The IR test results are influenced by specimen size and testing configurations. A study was conducted to investigate the influence of aspect ratio (length/diameter) of laboratory specimens on the frequency response of asphalt concrete when tested with the IR. The IR test, performed in a longitudinal mode, demonstrated that the test is repeatable and reproducible. The test results indicated that the frequency response increased as the aspect ratio increased approximately up to 0.7, and then it decreased with a nonlinear trend as the aspect ratio increased beyond 0.7, indicating that the tendency of the frequency response reached a plateau as the aspect ratio increased. It was inferred from the test results that there was a threshold aspect ratio at which the fundamental longitudinal frequency mode was not the dominant frequency mode. Velocity calculations from measured resonant frequencies indicated that the true material properties for the longitudinal mode could be attained at an aspect ratio of as low as 1.In another study, the sensitivity of the resonant frequency response of the IR testing of asphalt concrete to asphalt concrete mixture parameters was investigated. The IR tests were performed on disk-shaped asphalt concrete specimens at the transverse (flexural) mode of vibration at a temperature range of approximately -10 to 50oC. Test results revealed that the relationship between the resonant frequency and temperature was described by a polynomial fit, and it was shown through statistical analysis that the slopes of the fit were significantly aected by mixture parameters such as air void content and binder content. Also, the statistical formulation (predictive model) between the resonant frequency and the asphalt concrete mixture parameters were established for a given aggregate gradation of nominal maximum size and an aggregate specific gravity. The prediction accuracy of the model was evaluated by independent data sets, and the test results indicated that the maximum error between the measured and predicted resonant frequencies was not more than 9 percent.In an eort to characterize the properties of recycled asphalt pavement (RAP) binder with the IR test through asphalt concrete mixture testing, two approaches were utilized. An approach is proposed for determination of binder properties through the IR testing of mixtures with RAP and binders with known engineering properties. The IR tests were performed in the longitudinal mode at a range of temperatures between 3 and 35oC. Also, RAP binder and virgin binders were tested using dynamic shear rheometer (DSR) at the same temperature range as the IR testing. It was seen that the IR test ranked the expected trend of binder stiness with respect to the resonant frequency of mixtures. The results indicate the potential of the proposed concept and feasibility of the approach in determining binder properties, including properties of the RAP binder. A practical method is proposed for determination of binder properties based on mixture testing.In the second approach, the IR test potential to characterize the low-temperature properties of an RAP binder that incorporated a rejuvenating agent was investigated. This approach included testing of mixes with virgin binders and pure RAP mixes treated with a rejuvenating agent at dierent levels using the IR, as well as testing of blends of recovered RAP binder, rejuvenator, and virgin binder using bending beam rheometer (BBR). The results showed that the IR test can properly rank the expected stiness of binders through mixture testing. The results also indicated high linear correlations between mixture properties obtained from the IR test (modulus and phase angle) and binder properties obtained from the BBR test (stiness and m-value, a relaxation index). The results clearly demonstrate the potential of IR to be used for grading and optimization for the asphalt binder of RAP and rejuvenator content in lieu of the binder recovery method.
Author: M. S. Aggour
Publisher:
ISBN:
Category : Concrete
Languages : en
Pages : 162
Get Book Here
Book Description
Author: A.F. Nikolaides
Publisher: CRC Press
ISBN: 1351063251
Category : Technology & Engineering
Languages : en
Pages : 716
Get Book Here
Book Description
Highway engineers are facing the challenge not only to design and construct sustainable and safe pavements properly and economically. This implies a thorough understanding of materials behaviour, their appropriate use in the continuously changing environment, and implementation of constantly improved technologies and methodologies. Bituminous Mixtures and Pavements VII contains more than 100 contributions that were presented at the 7th International Conference ‘Bituminous Mixtures and Pavements’ (7ICONFBMP, Thessaloniki, Greece 12-14 June 2019). The papers cover a wide range of topics: - Bituminous binders - Aggregates, unbound layers and subgrade - Bituminous mixtures (Hot, Warm and Cold) - Pavements (Design, Construction, Maintenance, Sustainability, Energy and environment consideration) - Pavement management - Pavement recycling - Geosynthetics - Pavement assessment, surface characteristics and safety - Posters Bituminous Mixtures and Pavements VII reflects recent advances in highway materials technology and pavement engineering, and will be of interest to academics and professionals interested or involved in these areas.
Author: SL. Whitmoyer
Publisher:
ISBN:
Category : Asphalt
Languages : en
Pages : 10
Get Book Here
Book Description
Various publications have demonstrated that the results from the resilient modulus test (see ASTM D 4123, Method for Indirect Tension Test for Resilient Modulus of Bituminous Mixtures) display a wide range of variability. Considering this, an alternate testing method that produced more consistent results with a simpler test setup was pursued. A standardized vibrational test procedure for Portland cement concrete (ASTM C 215, Test Method for Fundamental Transverse, Longitudinal, and Torsional Frequencies of Concrete Specimens) was modified to measure the material properties of asphalt concrete. The impact resonant method provided three separate, independent tests, two measuring the elastic modulus and one the shear modulus. Poisson's ratio was obtained by comparing moduli results. Unlike the semi-nondestructive nature of the resilient modulus test, the impact resonant method was a true non-destructive test. The method also allowed for a possible laboratory link to nondestructive analysis of in-situ pavement. Experimental test results demonstrated that the impact resonant method provided precise and reproducible results. Further experiments revealed that the impact resonant method could detect different magnitudes of microcrack healing.
Author: José Ludwig Figueroa
Publisher:
ISBN:
Category : Pavements
Languages : en
Pages : 250
Get Book Here
Book Description
Author: KM. Chua
Publisher:
ISBN:
Category : Asphalt emulsion mixtures
Languages : en
Pages : 18
Get Book Here
Book Description
It is often desirable to be able to obtain a comprehensive characterization of the performance-related properties of asphalt concrete with as few tests as possible. The New Mexico State Highway and Transportation Department is interested in obtaining a comprehensive characterization of the performance-related properties of the four types of asphalt concrete mixtures that are commonly used in the state. These properties include: the strength, the resilient modulus, the rutting characteristics, and the fatigue/cracking characteristics. Typically, different tests are needed to determine these characteristics. However, the approach taken here to obtain the desired information is through dynamic testing with large (15 cm diameter x 30 cm high) cylindrical asphalt concrete specimens at four different load levels, frequencies, and temperatures. The load applied were 1112 N, 2224 N, 4448 N, and 8896 N; at frequencies of 1 Hz, 4 Hz, 8 Hz, and 16 Hz. Test temperatures were 4.4°C, 25°C, 37.8°C, and 60°C. Continuous haversine load cycles were applied for each test set and the response to the repeated loadings were recorded. Resilient modulus histories were obtained. Rutting characteristics of the material at different temperatures were obtained from the residual deformation histories. The thermal viscoelastic properties were determined from the deformation response at the different temperatures. The change in the damping characteristics with repeated loading were determined through analysis of the data in the frequency domain. Since damping properties can be related to the embrittlement and aging characteristics of materials, the fatigue properties were also inferred. Additionally, it is shown that the degree of susceptibility of the asphalt concrete to cracking and reflection cracking can also be estimated.
Author: Myung Chan Roo
Publisher:
ISBN:
Category : Asphalt concrete
Languages : en
Pages : 360
Get Book Here
Book Description
Author: H. Wen
Publisher:
ISBN:
Category : Asphalt concrete
Languages : en
Pages : 7
Get Book Here
Book Description
A variety of testing methods are employed by researchers to characterize the fatigue performance of asphalt concrete. These testing methods need to be evaluated based on their performance to characterize the fundamental properties and field performance of mixtures. In this study, the indirect tensile tests and the uniaxial tests were investigated. The indirect tensile creep tests and the uniaxial tensile creep tests were performed on a North Carolina mix to study the characterization of the fundamental properties and on WesTrack mixes to study the characterization of field performance. It was found that that the values of creep compliance from the indirect tensile creep and the unaxial tensile creep tests on North Carolina mix cannot be compared favorably. Fracture energies from the indirect tensile strength tests on WesTrack mixes highly correlate with the field performances, while those from uniaxial direct tension tests did not match field performances. It is believed that anisotropicity could be the cause of differences in performance of the two test methods. It is disconcerting when researchers attempt to establish a constitutive relationship between the property parameters of mixtures and laboratory fatigue life using different testing methods, without knowing if the laboratory fatigue life from these testing methods really reflects field performance. Further research is needed to obtain a better understanding of different testing methods.
Author: Mohamed Ali Dhalaan
Publisher:
ISBN:
Category : Asphalt concrete
Languages : en
Pages : 311
Get Book Here
Book Description
