The feasibility is investigated of various acoustic (sonic), nuclear, and electrical techniques for nondestructive measurement of Portland cement and bituminous concrete pavement thickness both during and after construction. Recommendations are made for equipment development and field testing of three specific methods that could potentially result in such measurements with the desired degree of speed and accuracy.

Issues for 1963- include section: Urban transportation research digest.

The objective of this study was the development of criteria and design procedures for the use of aggregate riprap linings, which consists of a layer of discrete fragments of rock of sufficient size to resist the erosive forces of the flow. The design of such riprap-lined drainage channels involves the interrelationship between the discharge, the longitudinal slope, the size and shape of the channel, and the size distribution of the riprap lining. This report describes these interrelationships and develops design criteria by which a riprap-lined drainage channel can be proportioned and the riprap lining can be specified for a given discharge and longitudinal slope. The relationships so developed have been reduced to design charts, the use of which permits rapid and simple establishment of channel shape and size as well as of the properties of the riprap lining.

This report will be of primary interest to highway administrators and traffic planners who are concerned about the present and future service demands on the Interstate Highway System. This study compares the availability and the demand for (a) emergency services which are those normally supplied by police, tow vehicles and ambulances; (b) normal services which are routine services such as gasoline, food and lodging, and (c) supplemental services which include rest areas, signing for directions and services and a choice of service types, brands, prices, etc. Recommendations are presented which should remove some of the deficiencies found by the researchers.

The current state of knowledge with both studded tire performance and methods of assessing pavement wear is reported. An annotated bibliography is presented of all known research on this subject from the U.S. and European sources, a review and evaluation of the data and results of completed studies and recommendations for future research. The objectives of the study were confined to the following tests: (1) correlation of data on the frictional characteristics of studded tires on ice, packed snow, and on bare pavements, and (2) development of a method, or methods, of quantitative assessment of the difference in wearing and abrasive effects of studded versus unstudded tires on different types of surfaces. A stud-resistance coefficient for operation on ice was derived and all U.S. data are correlated with this parameter and ice temperature.