The cost is defined in Eq. (5), where pi are unit prices andmi aremeasurements.
The cost function includes the materials (concrete, active
prestressing steel, passive reinforcement steel) and all the elements to
evaluate the entire cost of the bridge construction. Unit prices were obtained
from a survey of Spanish contractors and subcontractors of precast
structures and adapted to current prices. The values are given in
Tables 1, 3 and 4 [42].