Rehabilitation and Maintenance System District Time Optimization (RAMS- DTO-1)

The formulation and solution of the multi-year District Rehabilitation And Maintenance problem is presented. The problem is formulated as a 0-1 integer nonlinear programming problem (INLP) and the solution methodology uses the concepts of relaxation, decomposition, and network formulation to convert the 0-1 INLP problem into 0-1 integer linear programming problems (ILP). A highway maintenance problem is formulated using real data from District 17 and is solved by the computer program based on the proposed solution methodology. The sample problem had 15 highway segments, 6 distress types, 9 rehabilitation and maintenance strategies and a 10 year planning period. The INLP had 1350 0-1 variables and the problem was solved in approximately 35 seconds of CPU time on the AMDAHL 470V/6 computer at the Texas A&M University Campus. It was concluded that the proposed mathematical model and the algorithm is a good tool for solving the time optimization problems involved in the rehabilitation and maintenance of highway segments at the District level.