bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation Of Initial and Failure Stiffness Definitions in Flexure Fatigue Test for Hot Mix Asphalt
Authors: Witczak MA , Mamlouk MW , Kaloush MS , Kaloush KE 
Published: March 2009

Abstract
Flexural beam fatigue testing of asphalt mixtures has been used for nearly 40 years in the pavement industry. Since the development of the test, the definitions of initial and failure stifnesses have not been verified or validated in any comprehensive study. The main objective of this study is to validate the criteria used to define the initial and the final stiffnesses in flexure fatigue testing. In this study, extensive flexure fatigue tests were performed on five typical dense-graded mixtures and an asphalt rubber gap-graded mixture. An optimization approach was used, in which different intial and failure conditions were assumed. Fatigue models were developed using linear regression curve fitting and the conditions that produced the best fit were selected. Both the phenomenological and the dissipated energy approaches were used. Test results conclusively indicated that the initial stiffness should be defined at cycle number 50. In addition, when a phenomenological approach for fatigue is employed, the fatigue stiffness should be taken at 50% of the initial stiffness.A stiffness degradation model was developed, which provided an independent proof that failue occurs when the stiffness of the beam is reduced to 50% of the initial stiffness. This model represents a basic material propertey at which damage accumulation in the mixture has produced an inability of the mix to resist further damage independent of the mode of loading. In contract to the tensile strain-failure approach, data analysis with the energy approach showed that fatigue failure stiffness, taken at 30% of the initial stiffness, provided identical fatigue energy failure regardless of constant stress or strain mode of loading. The results show that the phenomenological and energy approaches provide different definition of failure and the test should be consistent with the method of analysis used.
A Journal Bearing Test Rig With Reduced Uncertainty: Some Design Considerations
Authors: Wale D. , Mba D. 
Published: March 2009

Abstract
This paper presents results from a design study for a new journal bearing test rig intended to set new standards of accuracy. The paper summarizes a review of previous rigs and experimental techniques, with consideration and selection of the general design features most likely to give high accuracy in a new rig. Certain sources of error are identified and described, including those associated with the measurement system and build errors. A numerical assessment of the sensitivity to errors in selected experimental configurations is presented. In addition, methods of controlling uncertainties are discussed. This paper would be of interest to practicing engineers and researchers, either already involved, or new, to experimental journal bearing testing.
Influence of the Calibration Points on theSpb Parameter Behavior
Authors: Wainstein JE , Cocco RG , de Vedia LA , Cassanelli AN 
Published: March 2009

AbstractThe present work studies the separability parameter Spb behavior to estimate crack lengths when two or three calibration points are used. A set of precracked and blunt notched specimens with three-point bend ASTM-SE(B) geometry were prepared from three materials: AA 6061-T6 aluminum alloy with different side groove ratio, high-strength low-alloy welded steel, and 2.25Cr-1Mo steel. For each precracked specimen, initial and final crack length were measured on the crack surface. Intermediate crack lengths were determined by two methodologies: the standard elastic unloading and the Spb parameter method using two and three calibration points. The Spb crack lengths were very close to those estimated using the standard methodology; differences between them were less than 15 % Δa, suggested as a difference limit value in ASTM E 1820-99 to alternative methods for measuring crack extension. The performance of Spb parameter was evaluated using two and three calibration points. J-R curves were constructed. The JIQ values obtained by the standard methodology and the Spb method were similar.
Stress Evaluation of Railroad Forged Wheels by Ultrasonic Testing
Authors: José Minicuci D , dos Santos Júnior AA , Andrino MH , de Carvalho Santos F 
Published: March 2009

Abstract
Many railroads and research institutes have developed nodestructive testing methods in order to prevent accidents and remove the wheels from service before they fail. One of the most promising alternative means of performing this type of inspection is the evaluation of the stress on the forged wheel rim by ultrasonic testing. The main purpose of this test is to detect the wheel rim stress variations. MWL Brasil, with UNICAMP (State University of Campinas)'s support, applied a stress analysis method by ultrasonic test, using longitudinal critically refracted waves (Lcr). The magnitude of stress found was compared with simulation in infinite elements presenting consistent results.
Anisotropy of Field-Compacted Asphalt Concrete Material
Authors: Motola Y , Uzan J 
Published: March 2009

Abstract
This note presents a study to quantify the degree of anisotropy induced in situ by the compaction equipment. Large asphalt concrete samples were cut from the field and sawed in the laboratory to give prismatic specimens 200 × 80 × 80 mm3. The specimens were tested in all directions, at 40°C, using low sinusoidal load. The dynamic modulus obtained at different frequencies was used as the indicator of anisotropy in the three principal directions. Analyses of variance were conducted. They indicated that the material is not isotropic, but rather cross-anisotropic.
Testing and Evaluation of Quality Changes of Treated Fresh-Cut Tropical Fruits Packaged in Thermoformed Plastic Containers
Authors: Singh S. Paul , Chonhenchob V. , Chantarasomboon Y. , Singh J. 
Published: March 2009

Abstract
Fresh-cut fruit accounted for nearly $300 at retail in the U.S. in 2004, with projected sales ranging between $1 and $2 billion by 2008. The choice of packaging materials and the atmospheric conditions both inside and outside the package contribute significantly to the shelf-life of these products. This study evaluated quality changes such as firmness, color, total soluble solids (TSS), titratable acidity (TA), sensory quality, and microbial safety of fresh-cut mangoes, pineapples, melons, and mixes of these fruits. Chemical treatments to reduce browning, firmness loss, and decay for these fruits were also investigated. The most effective treatments for fresh-cut mangoes, pineapples, and melons were 0.1 M ascorbic acid, 0.2 M ascorbic acid, and 0.2 M ascorbic acid plus 0.2 M calcium chloride, respectively. These fresh-cut tropical fruits were packaged in three semi-rigid containers made of polyethylene terephthalate (PET), oriented polystyrene (OPS), and oriented poly(lactide) (OPLA). Gas composition in the package headspace and the time to reach steady-state conditions were observed to vary among fresh-cut packaging systems and affected their quality and shelf-life. The effects of package permeability, with regards to O2 and CO2, on quality and shelf-life of the fresh-cut products are discussed in this paper. Extended shelf-life was observed in fresh-cut mangoes, pineapples, and mixes packaged in PET due to reduced O2 and elevated CO2 atmosphere. Modified atmosphere of 6% O2 and 14% CO2 achieved in PET extended the shelf-life of fresh-cut pineapples from 6 to 13 days. The results suggest that shelf-life of fresh-cut fruit could be extended using appropriate semi-rigid containers.
Quality Assurance of Manufactures by Means of Intelligent Tomographic Processing
Authors: Barbuzza RG , Vénere MJ , Clausse A 
Published: March 2009

Abstract
Quality standards in industry require highly rapid and reliable inspection tools to optimize the production. In this article, a tomographic technique for defect inspection of manufactures is presented. Previous knowledge of the geometry of the inspected objects is used to shorten the inspection time. The location and dimension of internal defects can be determined rapidly from a few projections, providing valuable data for quality control.
Characterization of Thermal Degradation of Liquid Amine Anti-Strip Additives in Asphalt Binders Due to RTFO and PAV-Aging
Authors: Wasiuddin Nazimuddin M. , Fogle Chris M. , Zaman Musharraf M. , O’Rear Edgar A. 
Published: March 2009

Abstract
In this study, thermal degradation of amine-based liquid anti-strip additives was evaluated due to RTFO-aging and PAV-aging according to AASHTO T 240 and AASHTO R 28 test methods, respectively. The surface free energy (SFE) characteristics of asphalt binders before and after aging were used as a tool for this evaluation. Two asphalt binders, namely PG 64-22 and PG 70-28, and two anti-strip additives, namely AD-Here HP Plus and Redicote E-6, were evaluated. It was observed for 0.75 % AD-Here HP Plus in PG 64-22, mixing at 163°C is more effective than mixing at 145°C with respect to increase in SFE. Also, both RTFO and PAV-aging decrease the total SFE of asphalt binders; both the aging processes are more effective in PG 64-22. In addition, the beneficial effect of anti-strip additives in acid-base characteristics of asphalt binders is severely reduced by RTFO and PAV-aging. Finally, the chemical model of asphalt binder, proposed by Wasiuddin et al., was expanded to include the SFE characteristics of asphalt binders due to aging.
Medical Image Semi-fragile Watermarking in the Frequential Field
Authors: Kallel Imen Fourati , Lapayre Jean-Christophe , Bouhlel Mohamed Salim 
Published: March 2009

Abstract
Medical imaging requires great integrity of content since any change in the image even in a slight amount might affect the diagnosis. Semi-fragile watermarking could be the best technique to provide an efficient image authentication tool for medical images. In this paper, we propose a semi-fragile watermarking technique for the tamper proofing of still images that can tolerate JPEG lossy compression to a predetermined lowest quality factor and rejects any replacement process. We also present comparison performance for the proposed algorithm to eight other common techniques.
High Performance Stucco to Optimize Moisture Management in Wood-Frame Stucco Walls
Authors: Mukhopadhyaya Phalguni , Kumaran Kumar , Plescia Silvio , Lackey John , Normandin Nicole , van Reenen David 
Published: March 2009

Abstract
Stucco or portland cement plaster is widely used in North America as an exterior cladding material for the wood-frame walls. Recent computer-based numerical simulation studies at the National Research Council (NRC) Canada, Institute for Research in Construction (IRC) have indicated that low liquid diffusivity and high water vapor permeability of the stucco material can positively influence the overall moisture management capacity of wood-frame stucco walls. This paper presents the results from experimental and numerical modeling studies carried out at the NRC-IRC on the development of high performance stucco materials and its effect on the overall moisture management capability of wood-frame stucco walls. Liquid water and water vapor transmission properties of several commercial/conventional stucco materials and some newly formulated compositions were measured and compared under laboratory conditions. The experimental results suggest that by appropriate choice of the mix composition, addition of a proper hydrophobic admixture, and using aggregates with a hydrophobic coating, stucco material with lower liquid water diffusivity can be produced without reducing the water vapor permeability. The results from the numerical modeling study show newly developed high performance stucco materials can significantly improve the moisture management capability of wood-frame stucco walls.
Analysis of Major, Minor Constituents and Various Phases in Carbon Brush by Classical Gravimetry, Titremetry, and by Instrumental Method
Authors: Singh Nahar , Rashmi  , Singh Niranjan , Gupta Prabhat K. 
Published: March 2009

Abstract
A new precise chemical method has been developed for the compositional analysis of carbon brush. The major chemical constituents of carbon brush are carbon (C), copper (Cu), lead (Pb), and tin (Sn), while the minor constituents are silica (SiO2), iron (Fe), and molybdenum (Mo). The analytical techniques employed for graphitic carbon, Pb, Sn, and SiO2 analysis were gravimetry (Loss in ignition, as PbSO4, as metastannic acid, and as SiO2, respectively) and titremetry for copper (Iodimetry). Trace impurities of Fe and Mo were determined by flame atomic absorption spectrometry (FAAS). On the same sample, gravimetric methods as above have been compared for Cu (as cuprous thiocyanate) by gravimetry and for Pb and Sn by normal titremetry (EDTA with xylenol orange as indicator). XRD confirmed the presence of graphitic carbon in carbon brush. The major constituents (w/w %) of carbon brush for Cu, C, Pb, Sn, and SiO2 were found to be 40.5±0.3, 39.5±0.25, 9.5±0.10, 10.2±0.13, and 0.45±0.07, respectively, and minor constituents Fe and Mo were found to be 4.2±0.21 and 1.6±0.2 mg kg−1, respectively. The titremetry Cu results obtained are comparable by gravimetry, which were 40.8±0.5. The gravimetric results obtained for Pb and Sn are comparable by titremetry and FAAS results of SiO2, which were 9.3±0.30, 10.1±0.2, and 0.25±0.09 (w/w %), respectively. The comparability of the above gravimetric and titremetry methods for various constituents are in good agreement with the methods presented in this paper for carbon brush and have been found to be reproducible within an uncertainty of 1.5 % RSD.
Forensic Investigation of Mechanically Stabilized Earth (MSE) Approaches
Authors: Chen Dar Hao 
Published: March 2009

Abstract
A forensic study was performed to determine: (1) the extent of voids in the retaining wall backfill in the first 1 m behind the wall panels; (2) the extent of moisture in the suspected wet areas where the District is planning to add turnarounds under the bridges; (3) severity of bridge approach settlement and its ride quality; and (4) whether or not there is global stability concern for FM (Farm to Market) 310, FM 1304, and Chatt Rd. mechanically stabilized earth (MSE) walls. Ground penetration radar (GPR), dynamic cone penetration (DCP), drilling, elevation surveys, and instrumentation was performed in this study. Although voids and soft layers were found under the concrete slab, they are all near the MSE wall. Periodic survey results from April 2006 to March 2007 indicate that there is no significant settlement (&lt;10 mm). The piezometer measurements in the MSE walls indicate that the water table was low. The safety factor was found to be 1.4, which is above the minimum requirement of 1.3. Therefore, it was concluded that there is no global stability issue. Longitudinal profiles collected in June 2006 and July 2007 indicated that the maximum settlement in one year was found to be 6 mm for the Chatt Rd. overpass. Although there are some settlements on other overpasses, they are all less than 5 mm. There are no criteria on annual allowable settlement for bridge approaches. Thus, it was decided to continue to monitor the approach slabs without any immediate rehabilitation.
Adhesive-Bonded Anchorage Pullout Test to Estimate In-Place Concrete Compressive Strength
Authors: Cui Shiqi , Wang Jinshan , Kong Xuwen , Liu Yan , Jiang Liping 
Published: March 2009

Abstract
A new method called the adhesive-bonded anchorage pullout test is proposed in the paper to estimate the in-place concrete compressive strength. In this method, a threaded metal insert is anchored into the concrete by means of a high strength adhesive. To estimate the concrete compressive strength, the pullout force when the anchorage system fails is measured. The embedded depth and the diameter of the reaction ring are determined by theoretical and experimental analysis. The empirical correlation relationships between the pullout forces of this new method and the compressive strengths of concrete cubes are presented for concrete specimens with varying concrete mixes in the 10–80 MPa strength range. In order to assess the accuracy of this method on site, verification tests are undertaken on a number of concrete structures. The experimental and analytical studies show that the newly proposed method is accurate in estimating the in-place concrete compressive strength.
Comparisons of Five Computational Methods for Transverse Profiles
Authors: Chen Dar Hao , Li Zheng 
Published: March 2009

Abstract
Pavement funding allocation and rehabilitation/maintenance decisions are often based on the degree of rutting. Thus it is critical to have accurate rut measurement. In this study, five different sensor setups and computation algorithms were investigated which include: (1) 5-sensor stringline, (2) 3-sensor average, (3) 5-sensor maximum, (4) 7-sensor stringline, and (5) 7-sensor maximum. The 94 transverse profiles utilized in this study included six profiles from the standard 3.7-m wide pavement (with a well-defined rut basin) and 88 profiles from narrow pavements with a possible edge drop off. It was found that the 5-sensor maximum method yielded the best accuracy for both standard 3.7-m wide and narrow pavements. It is surprising to find that the 3-sensor average yielded better results than the 5-sensor stringline method. Also, regardless of the number of sensors (either 5 or 7) or pavement width (standard or narrow), the stringline method always underestimated the rutting. Based on the available data and analyses performed, it is concluded that, without altering the existing sensor configuration, the accuracy would improve significantly by changing the computation algorithm from 5-sensor stringline to 5-sensor maximum.
Evaluating the Shear Resistance of Hot Mix Asphalt by the Direct Shear Test
Authors: Wang Hai-nian , Liu Xi-jun , Hao Pei-wen 
Published: March 2009

Abstract
The shear strength of hot mix asphalt (HMA) was evaluated with a direct shear device in this research. The indirect unconfined compression test was adopted to calculate the cohesion and the angle of friction of HMA mixtures. The influence of asphalt content, loading rate, and testing temperature on the shear strength of HMA mixtures was also investigated. The shear resistance properties of asphalt mixtures were investigated by a direct shear device using five gradations (i.e., two intermediate-graded and three large-stone mixtures). The results show that the shear strength is highly related to rutting resistance of the HMA mixture at a high temperature. Testing parameters have great influences on the cohesion component and low influences on the angle of friction. The shear strength of asphalt mixtures has good correlations with the dynamic stability through wheel-tracking tests. The angle of friction is susceptible to the mixture gradations and their design methods. The well-interlocked gap-graded mixtures have greater friction angles than the continuously dense-graded mixtures.
Novel Method of Evaluating Dynamic Repeated Measurement Uncertainty
Authors: Zhongyu Wang , Leyi Ge 
Published: March 2009

Abstract
Uncertainty evaluation of dynamic repeated measurement is usually a difficult problem. Different from conventional methods, we used a novel method to evaluate the dynamic repeated measurement uncertainty in this paper: (1) When calculating an expectation function, we use a high order Legendre orthogonal polynomial fitting instead of the least squares method, so as to eliminate morbidity phenomenon that sometimes appeared in the application of the conventional method. (2) Using the measurement data and the accurate expectation function, we analyze some statistical characteristics of the dynamic repeated measurement random errors, according to these, we use a random number generator to generate lots of random numbers simulating the random errors in all discrete sampling points and acquire a large size of dynamic repeated measurement simulation data. (3) We get the dynamic repeated measurement uncertainty of all discrete sampling points in terms of calculating standard deviation. Finally, using a special example, we derived some evaluation results from this novel method, the conventional Bessel method and the conventional Grey System method, respectively. This novel evaluation method is proved by the identical results of the three methods.
On-Site Environmental Conditions—Do They Really Affect the Measuring Accuracy?
Authors: Geršak G. , Bojkovski J. , Batagelj V. , Hudoklin D. , Begeš G. , Pušnik I. , Drnovšek J. 
Published: March 2009

Abstract
According to requirements of the ISO/IEC 17025:2005 standard, environmental conditions while calibrating are monitored and stated in the calibration certificate. In this paper we present an experiment for evaluation of the behavior of our on-site measuring equipment regarding its specifications and the suitability of these specifications for our typical on-site work. We built a measuring setup for determining the temperature and relative humidity dependence of our on-site equipment. Main units of the equipment were placed in a climatic chamber, while temperature sensors and humidity sensors were placed into an ice bath and humidity generator, respectively. The temperature and relative humidity conditions in the climatic chamber were changed incrementally from 5°C to 45° and from 80 % to 20 %. Results are presented and evaluated. The built measuring setup was proven to be a useful tool for determining the temperature and relative humidity dependence of our on-site equipment. By observing the dynamic transitions of the instrumentation between changes of conditions possible dynamic effects could be evaluated also.
Flexural Creep Apparatus and Testing for Structural Composite Lumber
Authors: Leichti Robert , Clauson Milo , Cheney Daniel 
Published: March 2009

Abstract
A specification to test and evaluate the flexural creep and duration of load effects for structural wood-based products was finalized as ASTM D 6815-02. The test method requires relatively large forces be sustained for at least 90 days. Further, the test is conducted in an environment that is moisture and temperature controlled. The typical apparatus for this test uses weights and ratio pulleys, but the heavy loads make loading and unloading difficult and potentially dangerous and the footprint must be large enough to provide space for lifting. This paper describes an apparatus that requires a minimum of floor space and uses hydraulic loading so that it is safer to load and unload. Operation and typical data for the test are used to demonstrate the specification and the apparatus.