Application of mathmatical programming in the optimization of hazard mitigation of debris flow along expressway

Optimal analysis in the mitigation of debris flow hazard was generally conducted with expert judgments or by simply scheme option, which would get inadequate and uneconomic decision sometimes. Set of feasible scheme in the mitigation of debris flow hazard along expressway was proposed with constraints according to the mathematical programming methods. The full set of mitigation modes was served as initial condition, which help to reduce the inadequate of decision. The order of priority of each kind of mitigation mode was suggested, as well as the analysis procedure in the proposing of feasible schemes, which proposed a theoretical rule, not empirical, to guide the analysis of mitigation scheme. Gradual constraint method was employed to assign the influencing factors of decision-making to constraint analysis in each grade, which resulted in a reduced amount of factors to be considered in each grade and help to enhance the analysis efficiency and reduce the difficulty at the meantime.