THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

The American Society for Testing and Materials (ASTM) is an independent organization devoted to the development of standards.

American Society for Testing and Materials

Polymer modified asphalt binders

The urban heat island effect, its causes, and mitigation, with reference to the thermal properties of asphalt concrete.

Conventional impervious pavements have dark surface and large thermal inertia. During summertime they tend to absorb and store solar radiation but negate the evaporative cooling, contributing to the development of urban heat island (UHI). The idea of using cool pavements to mitigate the UHI has gained momentum recently. This review synthesizes the existing definition, physical mechanism, and typical cooling techniques of cool pavements, presenting the influence of cool pavements on the urban thermal environment. Benefits, penalties, costs and policies for the applications of cool pavements are presented with special emphasis on reflective pavements and evaporative pavements. The review suggests that the definition of cool pavements remain incomplete; that the influence of cool pavements on the air temperature in the urban canopy layer is unknown; and that the impact of cool pavements on the thermal conditions of adjacent buildings and pedestrians remains unknown. Many speculations of using cool pavements to battle the UHI effect need refinements and validations. Heat-harvesting pavements seem interesting because they not only stay cool but harness renewable energy. However, the results from the heat-harvesting pavement prototype require scrutiny on the power output, durability, and lifetime of the pavement system. Future studies are expected to understanding the impacts of cool pavements on pedestrian thermal stress, on adjacent building’s energy loads, and on the air temperature in the urban canopy layer.

A review on the development of cool pavements to mitigate urban heat island effect

An experimental study on the water-purification properties of porous concrete

The feasibility of using concrete containing recycled asphalt pavement (RAP) in concrete pavement applications was evaluated. Concrete containing 0%, 10%, 20%, and 40% of RAP were produced in the laboratory and evaluated for their properties that are relevant to performance of concrete pavements. Results of the laboratory testing program indicate that compressive strength, splitting tensile strength, flexural strength, and elastic modulus of the concrete decreased as the percentage of RAP increased. The coefficient of thermal expansion and drying shrinkage did not appear to be significantly affected by RAP content. When a finite element analysis was performed to determine the maximum stresses in typical concrete pavements in Florida under critical temperature and load conditions, the maximum stresses in the pavement were found to decrease as the RAP content of the concrete increased, due to a decrease in the elastic modulus of the concrete. Though the flexural strength of the concrete decreased as RAP was incorporated in the concrete, the resulting maximum stress to flexural strength ratio for the concrete was reduced as compared with that of a reference concrete with no RAP. This indicates that using a concrete containing RAP could possibly result in improvement in the performance of concrete pavements.

Concrete Containing RAP for Use in Concrete Pavement

An experimental and analytical study was conducted to develop an effective method for determining realistic thermal-load induced stresses in concrete pavements. Temperatures throughout the concrete slabs were measured over an extended time period. Resulting critical stresses were then analytically derived following the procedure developed in this study. To verify these analytical stresses, load-induced strains and deflections were recorded at numerous locations on the test slab at various time periods, using the falling weight deflectometer as a loading device. The findings confirmed the importance and the need to account for the thermal gradient in the design and analysis of concrete pavements. The temperature data indicated that the temperature distributions were mostly nonlinear and can be represented fairly well by a quadratic equation. In addition, theoretical analysis of the induced stresses suggests the consideration of the total temperature distribution throughout the concrete slab depth rather th...

Analysis and Verification of Thermal-Gradient Effects on Concrete Pavement

Specific objectives of this project were as follows: (1) Evaluate the measurement system for the existing Strategic Highway Research Program (SHRP) Indirect Tension Tester (IDT) to identify improvements that need to be made to make the test more practical and reliable; (2) Develop an improved measurement system based on the findings of this evaluation; (3) Evaluate existing data acquisition and data reduction software for the SHRP IDT to identify limitations and deficiencies associated with the determination of relevant asphalt mixture properties; (4) Develop and evaluate data acquisition and data reduction software as necessary to determine relevant asphalt mixture properties from the SHRP IDT; (5) Determine the minimum amount of mixture testing required to reliably determine the master creep compliance curve of asphalt mixtures by evaluating the use of empirical and theoretical relationships between properties of asphalt binders and asphalt mixtures, including the binder-to-mixture stiffness relationship developed for use in the Superpave mixture design and analysis system; (6) Develop and evaluate a method and data reduction software to generate the master creep compliance curve automatically from creep compliance test results at multiple test temperatures; (7) Use the SHRP IDT and the measurement and data analysis procedures developed to determine the properties of several typical asphalt mixtures used in Florida and use the data to illustrate how the data can be used to evaluate the performance of asphaltic mixtures; and (8) Establish recommendations for further development and implementation of the SHRP IDT to establish an implementable testing system that can be used to establish an asphalt mixture specification based on asphalt mixture properties and/or parameters that control the cracking mechanisms of asphalt pavements and overlays The results of this study are presented in the following chapters: (1) Introduction; (2) Evaluation of Existing SHRP IDT; (3) Evaluation of Binder-to-Mixture Stiffness Relationships; (4) Improvements to the SHRP IDT Testing and Analysis System; (5) Resilient Modulus from SHRP IDT; (6) Modulus and Failure Limits from SHRP IDT Strength Test; (7) Creep Compliance Curve and m-Value from SHRP IDT; (8) Asphalt Mixture Performance Evaluation Using the SHRP IDT; (9) Future Development and Implementation of the SHRP IDT; and (10) Closure (Summary)

Evaluation of shrp indirect tension tester to mitigate cracking in asphalt concrete pavements and overlays

The results are presented of an experimental and analytical study to determine the actual temperature distribution within typical concrete pavement slabs and to evaluate the effects of nonlinear thermal gradients on the behavior of concrete pavements. The temperature data obtained in this study indicated that the temperature variations within the pavement slabs were mostly nonlinear. The temperature distribution throughout the depth of a concrete pavement slab can be represented fairly well by a quadratic equation. When the distribution is nonlinear, the maximum computed tensile stresses in the slab tend to be lower for the daytime condition and higher for the nighttime condition as compared with the stresses computed with the consideration of a linear temperature distribution.

Mang Tia

Papers

An experimental study on the water-purification properties of porous concrete

Concrete Containing RAP for Use in Concrete Pavement

Analysis and Verification of Thermal-Gradient Effects on Concrete Pavement

Evaluation of shrp indirect tension tester to mitigate cracking in asphalt concrete pavements and overlays

Nonlinear temperature gradient effect on maximum warping stresses in rigid pavements