High-speed texture measurement of pavements.
This study was conducted to validate high-speed texture measuring equipment for use in highway applications. The evaluation included two high-speed systems and a new static referencing device. Tests were conducted on 22 runway and taxiway test sections from the National Aeronautics and Space Administration's Wallops Flight Facility and 7 surfaces from Virginia's Smart Road. Texture estimates recorded with the high-speed (dynamic) equipment correlated extremely well with estimates made with static referencing methods. The system developed by International Cybernetics Corporation was very functional for most conventional highway surfaces. However, a better correlation may be achieved with the referencing methods by using a system (such as the MGPS surface system developed by the Federal Highway Administration) that produces the American Society for Testing and Materials' standard mean profile depth. Finally, an analysis conducted using the CTMeter (circular track meter, a laser-based but static system) demonstrated an important advantage of combining indices produced from high-definition surface profiles. By comparing the mean profile depth with the root mean square data for a particular surface, it is possible to characterize more fully the shapes that contribute to a pavement's macrotexture.
Pavement Friction and Skid Resistance Measurement Methods: A Literature Review
Driving safety is of significance in the automobile industry and transportation systems. Pavement skid resistance has long been recognized as the most important parameter in reducing traffic accidents especially in wet conditions. The knowledge of the friction coefficient and skid resistance is very valuable information for safety enhancement of roads. Thus, it is important to find proper methods for measuring skid resistance and frictional properties of the pavement surface. There is a wide range of measurement methods and devices for measuring skid resistance. This paper presents a review on the research studies that have been done on characterization of the frictional properties of the pavement surface and discussed methods used for measurement and evaluation of texture characteristics and the strengths and weaknesses of these methods. Finally, some ideas have been suggested to develop new methods for better and proper measurement of skid resistance.
Investigation of International Standard, International Electrotechnical Commission, IEC 62305 and Indian Standard IS 2309 in positioning the Air Terminals (ATs)
From 18th Century onwards, many scientists and researchers across the globe have conducted experiments and researches related to the subject called Lightning and as a result they have acquired success in protecting the structures against lightning strokes to a great extent. However, the science behind lightning has not been completely discovered and therefore any design of lightning protection scheme can’t be certified as cent percent safe. Here in this paper, a cuboid equivalent to a rectangular industrial building has been taken into consideration. Lightning Protection Scheme for the same has been designed in two ways: i) based on the Protective Angle Method and Rolling Sphere Method as per International Standard IEC 62305 and ii) based on the Protective Angle Method as per Indian Standard IS 2309. This paper mainly focuses on the comparison of those two designs which ultimately discloses the difference in safety level that we are having by adopting a particular standard.