Citation

Lamm R, Steffen H, Guenther AK. Transp. Res. Rec. 1994; 1445: 64-72.

Copyright

(Copyright © 1994, Transportation Research Board, National Research Council, National Academy of Sciences USA, Publisher SAGE Publishing)

DOI

unavailable

PMID

unavailable

Abstract

A procedure for evaluating the horizontal alinement of two-lane rural roads on the basis of three individual safety criteria is introduced. On the basis of these criteria, design practices are classified into three groups: good, fair, and poor. The procedure can be used to identify potential safety errors in new designs already in the planning stages as well as to detect safety deficiencies in existing roadways. To be effective, the safety evaluation process must be integrated into the modern highway design tools available to highway design engineers of today. These tools consist of computer-automated design (CAD) systems for highway geometric design and normally contain a component for the design of horizontal alinement. To incorporate the safety evaluation process into the horizontal alinement component of a commonly used CAD system, a subprogram for safety computations was developed on the basis of the three individual criteria. The safety evaluation process provides a future assessment of horizontal alinement on the basis of quantitative criteria. Consequently, safety impacts can be included along with the normally considered local, environmental, esthetic, and economic aspects in making decisions on a project. A case study of an existing two-lane rural roadway in southwestern Germany is included. On the basis of safety criteria, sections of the road have poor design. The safety evaluation procedure is applied to the identification of safer redesigns. In a first step for an economical redesign, still sections with fair design practices are included. In a second step for a redesign of an overall sound curvilinear alinement, only good design practices exist.

Language: en

Keywords

Accident prevention; Speed; Friction; Standards; Alignment; Curves (road); Engineers; Computer aided design; Reversible lanes; Geometry; Structural design; Error detection