Gray Evaluation Method of Concrete Pavement Comprehensive Condition

Evaluation of pavement condition is important in a pavement management system. In the existing evaluation methods, systematic analysis and regression modeling analysis are often used. But the former relies more on experienced judgment and the latter is restrained to use by the territory condition. For pavement evaluation, some data or properties relating to the environment and structure may not be very clear, and so the pavement system is gray in its nature. By applying the gray sole characteristic principle of the gray system theory, a comprehensive condition evaluation can be completed under partial data circumstances. In this paper, the principles used in the evaluation and selection of indexes are presented. In view of the gray characteristics of the pavement system, a set of comprehensive evaluating methods for concrete pavement organically combining the single indexes and a comprehensive index is presented. Dimensionless treatment is used to deal with the data, types of gray weight functions and their thresholds are determined, the gray weight function of each index when it belongs to a different gray class is introduced and deduced, and a general algorithm of the comprehensive condition evaluation is presented. Evaluations of various sections in a highway are carried out and compared.