Predicting Field Permeability from Testing Hot-Mix Asphalt Specimens Produced by Superpave Gyratory Compactor

2005 ◽  
Vol 1929 (1) ◽  
pp. 52-58 ◽  
Author(s):  
Kunnawee Kanitpong ◽  
Hussain Bahia ◽  
Jeffery Russell ◽  
Robert Schmitt
Keyword(s):  
Hot Mix Asphalt ◽  
Place Field ◽  
Simple Method ◽  
Air Voids ◽  
Good Relationship ◽  
Testing Procedures ◽  
Superpave Gyratory Compactor ◽  
Current Alternative ◽  
The Relationship ◽  
Better Than

This study was conducted to develop laboratory and field permeability testing procedures for design and quality control of Superpave® mixtures in Wisconsin. Sixteen mixes including fine-graded and coarse-graded mixes were evaluated. The in-place field permeability was measured by using the National Center for Asphalt Technology (NCAT) device, field cores were taken for measuring permeability in the laboratory by using the ASTM D5084 method, and laboratory compaction was used to prepare and test samples from loose mixtures recovered from the field. Two compaction procedures called Method A and Method B were used in this study to produce Superpave gyratory compacted (SGC) specimens that have thickness, air voids, and aggregate orientation similar to the field cores. Result indicates that Method B, based on the use of Ndesign gyrations for different sample sizes, can be used to produce samples that give permeability values similar to values measured for field cores. Results of this study also indicate a good relationship between field permeability (using the NCAT device) and lab permeability measured on field cores of fine-graded mixes with the amount passing No. 8 sieve (P8) higher than 45%. However, the relationship between field permeability and lab permeability measured on field cores of coarse-graded mix (P8 lower than 40%) is poor. It is concluded that the NCAT permeability device could possibly be used in the field for fine-graded mix (with P8 higher than 45%). However, to measure the field permeability of coarse-graded mix (P8 lower than 40%), there appears to be no current alternative better than taking field cores and testing them in the laboratory. For estimating permeability during mixture design, a simple method for preparing and testing permeability of SGC specimens and interpolating based on expected field density is introduced.

Evaluation of Superpave Gyratory Compaction of Hot-Mix Asphalt

1996 ◽  
Vol 1543 (1) ◽  
pp. 145-150
Author(s):  
E. R. Brown ◽  
D. I. Hanson ◽  
Rajib B. Mallick
Keyword(s):  
Hot Mix Asphalt ◽  
Current Data ◽  
Average Difference ◽  
Density Data ◽  
Air Voids ◽  
Superpave Gyratory Compactor ◽  
Gyratory Compaction ◽  
Pavement Temperature

To achieve 4.0 percent air voids in laboratory-compacted hot-mix asphalt with the Superpave gyratory compactor, different gyration levels are currently specified in the Superpave manual, each applicable to a particular combination of traffic and maximum pavement temperature. Two 1-year-old and four 2-year-old in-place densities were compared to those obtained from Superpave compaction of laboratory-prepared specimens and from compaction of reheated plant-produced mixtures. The gyration numbers corresponding to in-place density fell below 100 for all the mixes. At similar gyration levels, density of compacted, reheated, and laboratory-prepared specimens indicated an average difference of about 1 percent. Current data show that the Ndesign, Ninitial, and Nmax gyration levels may be too high, at least for lower traffic. Evaluation of the currently specified Ndesign values will be refined when the 3-year in-place density data become available.

Discrete Element Method (DEM) Analyses of Hot-Mix Asphalt (HMA) Mixtures Compaction and Internal Structure

2013 ◽  
Vol 639-640 ◽  
pp. 1287-1294 ◽  
Author(s):  
Jing Song Chen ◽  
Lei Zeng ◽  
Jian Yin
Keyword(s):  
Discrete Element Method ◽  
Hot Mix Asphalt ◽  
Coarse Aggregate ◽  
Asphalt Pavement ◽  
Asphalt Mixture ◽  
Point Of View ◽  
Compaction Process ◽  
Dem Simulation ◽  
Air Voids ◽  
Superpave Gyratory Compactor

Asphalt mixture compaction is an important procedure of asphalt mixture construction and can significantly affect the performance of asphalt pavement. In this paper, an open source DEM code was applied to simulate the compaction of hot-mix asphalt (HMA) with the Superpave gyratory compactor. The asphalt mixture compaction process, air voids distribution, internal coarse aggregate structure, and the effect of CA ratio were investigated from a microscopic point of view. The analysis results show that DEM simulation is an economical and effective approach to the research of asphalt mixture compaction, and has tremendous potential for asphalt mixture design.

Selection and Evaluation of Field Permeability Device for Asphalt Pavements

2000 ◽  
Vol 1723 (1) ◽  
pp. 73-82 ◽  
Author(s):  
L. Allen Cooley ◽  
E. Ray Brown
Keyword(s):  
Construction Projects ◽  
Hot Mix Asphalt ◽  
Ease Of Use ◽  
Asphalt Pavements ◽  
Air Voids ◽  
Additional Testing ◽  
The Relationship

Results of a study conducted to select, standardize, and evaluate a device to estimate the in-place permeability of hot-mix asphalt (HMA) pavements are presented. The study consisted of evaluating four different field permeameters in order to select and standardize a device that was correlated with laboratory permeability results, would provide repeatable results, and was easy to use. Additional testing on five HMA pavements was conducted with the selected device in order to evaluate the relationship between in-place pavement density and field permeability. The study entailed visiting three ongoing construction projects and conducting field permeability tests on newly compacted HMA pavements with each device. Also at each project, cores were obtained from which the laboratory permeability was determined. The data from each project were analyzed to determine which field permeameter correlated best with laboratory permeability, provided the most repeatable results, and was easy to use. Results of this study indicated that two permeameters did not show significant differences in results when compared with laboratory permeability results and had approximately the same amount of repeatability. For this reason, a field permeameter was selected on the basis of ease of use. This selected device was then taken to five additional HMA construction projects. At each project, field permeability testing was conducted, and the in-place density of pavements was obtained from cores. Relationships between in-place air voids and field permeability for all five projects were good: R2-evalues ranged from 0.63 to 0.82.

Effects of Testing Time and Confining Pressure on Falling-Head Permeability Tests of Hot-Mix Asphalt Concrete

2000 ◽  
Vol 1723 (1) ◽  
pp. 92-96 ◽  
Author(s):  
Kevin D. Hall ◽  
Josue Cruz ◽  
Hooi Ng
Keyword(s):  
Asphalt Concrete ◽  
Hot Mix Asphalt ◽  
Confining Pressure ◽  
Water Infiltration ◽  
Time Interval ◽  
Testing Time ◽  
Test Results ◽  
Testing Procedures ◽  
Superpave Gyratory Compactor ◽  
Flexible Wall

Superpave implementation has resulted in increased interest in the permeability of hot-mix asphalt concrete. Relatively open-graded Superpave mixes have given rise to concern about premature pavement failures due to increased water infiltration from the surface. Arkansas is investigating the use of a falling-head permeability test to evaluate Superpave mixes with respect to potential performance problems caused by increased permeability. The initial phase of the project concerns the development of laboratory testing procedures and equipment. Superpave field mixes from projects in Arkansas were sampled to investigate permeability testing parameters. In addition, compacted test specimens from a round-robin study of permeability were included in the testing matrix. For the Arkansas mixes, loose mix sampled at the hot-mix plant was compacted using the Superpave gyratory compactor. Field cores were also taken from completed pavement sections. Permeability tests were conducted on all samples to investigate the effect of testing time (15, 30, 45, and 60 min) and confining pressure (69 and 96.5 kPa) on the measured permeability values. Results of the testing suggest that neither the time interval used in measuring the head drop in a falling-head test nor the confining pressure used in the flexible wall testing apparatus significantly affects test results. These findings will greatly simplify testing methods and setup, making the test more attractive as a relatively routine tool for the mix design laboratory.

scholarly journals An Alternative Approach to Measure Co-Movement between Two Time Series

Mathematics ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 261 ◽  
Author(s):  
José Pedro Ramos-Requena ◽  
Juan Evangelista Trinidad-Segovia ◽  
Miguel Ángel Sánchez-Granero
Keyword(s):  
Time Series ◽  
Portfolio Management ◽  
Correlation Method ◽  
Simple Method ◽  
Derivatives Pricing ◽  
Statistical Arbitrage ◽  
Alternative Approach ◽  
Complex Relationships ◽  
The Relationship ◽  
Better Than

The study of the dependences between different assets is a classic topic in financial literature. To understand how the movements of one asset affect to others is critical for derivatives pricing, portfolio management, risk control, or trading strategies. Over time, different methodologies were proposed by researchers. ARCH, GARCH or EGARCH models, among others, are very popular to model volatility autocorrelation. In this paper, a new simple method called HP is introduced to measure the co-movement between two time series. This method, based on the Hurst exponent of the product series, is designed to detect correlation, even if the relationship is weak, but it also works fine with cointegration as well as non linear correlations or more complex relationships given by a copula. This method and different variations thereaof are tested in statistical arbitrage. Results show that HP is able to detect the relationship between assets better than the traditional correlation method.

RELATIONSHIP ANALYSIS OF WORK MOTIVATION AND PARTICIPATIVE LEADERSHIP TO UNDERSTAND FUNCTIONAL EMPLOYMENT BEHAVIOR

2020 ◽  
Vol 7 (2) ◽  
pp. 40-49
Author(s):  
Abdul Rivai
Keyword(s):  
Positive Relationship ◽  
Work Motivation ◽  
Work Behavior ◽  
Participative Leadership ◽  
Structural Position ◽  
Good Relationship ◽  
Relationship Analysis ◽  
Participatory Leadership ◽  
Study Population ◽  
The Relationship

This study aims to determine and understand the relationship between work motivation and participatory leadership with the work behavior of the Functional Staff of the Education and Culture Office of East Nusa Tenggara Province because the Province of East Nusa Tenggara is one of the provinces whose development and growth is relatively slower compared to other provinces in Indonesia. The study population was the functional staff who did not have a structural position of 94 people. Samples were taken as many as 75 people. Data collection using a questionnaire instrument.Based on hypothesis testing, this study found: (1) there was a relationship between work motivation and work behavior in which work motivation contributed 49.29% to work behavior, (2) there was a positive relationship between participative leadership and work behavior in which participative leadership contributed 51.49% of work behavior, and there is a positive relationship between work motivation and participatory leadership together with work behavior. Where work motivation and participatory leadership together contribute 67.01% to work behavior. From the three findings, the conclusions of this study are stated that: (a) Work behavior provides a good relationship to increase work motivation, (b) Work behavior can be improved by considering participatory leadership, by involving employees in every decision making, respecting opinions and proposals employees, and enhance collaboration.

scholarly journals Advertising Media Impact in Consumer Buying Behavior

2019 ◽  
Vol 8 ◽  
pp. 54-56
Author(s):  
Ashmita Dahal Chhetri
Keyword(s):  
Consumer Behavior ◽  
Young Male ◽  
Electronic Media ◽  
Buying Behavior ◽  
Media Impact ◽  
High Degree ◽  
The Impact ◽  
Buying Behaviors ◽  
The Relationship ◽  
Better Than

Advertisements have been used for many years to influence the buying behaviors of the consumers. Advertisements are helpful in creating the awareness and perception among the customers of a product. This particular research was conducted on the 100 young male and female who use different brands of product to check the influence of advertisement on their buying behavior while creating the awareness and building the perceptions. Correlation, regression and other statistical tools were used to identify the relationship between these variables. The results revealed that the relationship between media and consumer behavior is positive. The adve1tising impact on sales and there is positive and high degree relationship between advertising and consumer behavior. The impact on advertising of a product of electronic media is better than non-electronic media.

scholarly journals Comparative Study on Relative Fossil Energy Carrying Capacity in China and the United States

Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2972
Author(s):  
Zhili Zuo ◽  
Jinhua Cheng ◽  
Haixiang Guo ◽  
Yonglin Li
Keyword(s):  
United States ◽  
Carrying Capacity ◽  
The United States ◽  
Reference Area ◽  
Energy Sustainability ◽  
Fossil Energy ◽  
The Relationship ◽  
Population And Environment ◽  
Better Than ◽  
Innovative Concept

Based on resource carrying capacity, this study used the revised theory of relative resource carrying capacity (RRCC) and introduced an innovative concept of relative fossil energy carrying capacity (RFECC), which evaluates the degree of fossil energy sustainability based on the relationship between economy, population, and environment. This study took China and the United States as the study objects, took the whole country as the reference area, and calculated the RFECC of population, economic, and environmental resources from 2000 to 2018. Therefore, based on the comparative analysis, the following conclusions were drawn: (i) there is a big difference in the RFECC between China and the United States, which is manifested in the inverted U-shaped trend in China and the U-shaped trend in the United States; (ii) the relative fossil energy carrying states in China and the United States are different, mainly reflected in the economy and environment; (iii) the gap in RFECC between China and the United States has gradually widened; in general, China’s economic RFECC is better than that of the United States, while environmental RFECC and population RFECC in the United States is better than that of China; and (iv) coal and oil should be used as a breakthrough point for the sustainable fossil energy and sustainable development for China and the United States, respectively.

scholarly journals Fish bone-derived interconnected carbon nanofibers for efficient and lightweight microwave absorption

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Yangyang Gu ◽  
Peng Dai ◽  
Wen Zhang ◽  
Zhanwen Su
Keyword(s):  
Microwave Absorption ◽  
Carbon Nanofibers ◽  
Three Dimensional ◽  
Fish Bone ◽  
Absorption Properties ◽  
Simple Method ◽  
Microwave Absorption Properties ◽  
Absorption Performance ◽  
Microwave Absorption Performance ◽  
Better Than

AbstractIn this work, we demonstrated a simple method for preparing three-dimensional interconnected carbon nanofibers (ICNF) derived from fish bone as an efficient and lightweight microwave absorber. The as-obtained ICNF exhibits excellent microwave absorption performance with a maximum reflection loss of –59.2 dB at the filler content of 15 wt%. In addition, the effective absorption bandwidth can reach 4.96 GHz at the thickness of 2 mm. The outstanding microwave absorption properties can be mainly ascribed to its well-defined interconnected nanofibers architecture and the doping of nitrogen atoms, which are also better than most of the reported carbon-based absorbents. This work paves an attractive way for the design and fabrication of highly efficient and lightweight electromagnetic wave absorbers.

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