Road roughness is gaining increasing importance as an indicator of road condition, both in terms of pavement performance, and as a major determinant of road user costs. This paper defines roughness measurement systems hierachically into four groups, ranging from profilometric methods (2 groups), through response type road roughness measuring systems (RTRRMS's), and, subjective evaluation. The International Roughness Index (IRI) is defined, and the programs for it's calculation are provided. The IRI is based on simulation of the roughness response of a car travelling at 80 km/h. The report explains how all roughness measurements can be related to this scale, also when travelling at lower speeds than 80 km/h. The IRI emerges as a scale that can be used both for calibration and for comparative purposes.

Developing countries in the tropics have different natural conditions and different institutional and financial situations to industrialized countries. However, most textbooks on highway engineering are based on experience from industrialized countries with temperate climates, and deal only with specific problems. Road Engineering for Development (published as Highway and Traffic Engineering in Developing Countries in its first edition) provides a comprehensive description of the planning, design, construction and maintenance of roads in developing countries. It covers a wide range of technical and non-technical problems that may confront road engineers working in this area. The technical content of the book has been fully updated and current development issues are focused on. Designed as a fundamental text for civil engineering students this book also offers a broad, practical view of the subject for practising engineers. It has been written with the assistance of a number of world-renowned specialist professional engineers with many years experience in Africa, the Middle East, Asia and Central America.

Volume I: Experimental Investigation, documents an extensive series of measurements of the performance of a commercial inertial road profiling system (IRPS) and a commercial response-type road roughness measurement (RTRRM) system. Based upon the results of these measurements and upon an analysis of the operation of such equipment, calibration and testing guides, given in the Volume II were developed to assist users in assessment of IRPS and RTRRM functionality and operating performance.

This fully revised fourth edition of Max Lay’s well-established reference work covers all aspects of the technology of roads and road transport, and urban and rural road technology. It forms a comprehensive but accessible reference for all professionals and students interested in roads, road transport and the wide range of disciplines involved with roads. International in scope, it begins with the preliminary construction procedures; from road planning policies and design considerations to the selection of materials and the building of roads and bridges. It then explores road operating environments that include driver behaviour, traffic flow, lighting and maintenance, and assesses the cost, economics, transport implications and environmental impact of road use. It draws on Max Lay’s unparalleled consulting and operational experience in the financing, planning, design, construction, operation and management of roads in various countries. It forms an indispensable resource for transport planning, engineering, operations and economics.

This book contains the proceedings of the 4th International Conference on Sustainability in Civil Engineering, ICSCE 2022, held on November 25–27, 2022, in Hanoi, Vietnam. It presents the expertise of scientists and engineers in academia and industry in the field of bridge and highway engineering, construction materials, environmental engineering, engineering in Industry 4.0, geotechnical engineering, structural damage detection and health monitoring, structural engineering, geographic information system engineering, traffic, transportation and logistics engineering, and water resources, estuary, and coastal engineering.