A program for cost estimation of forest road construction using engineer's method

摘要

Modeling the cost of road construction is a prerequisite for evaluation and planning of different alternatives for low-volume road networks included in a forest management plan. In this paper, a model for cost estimation of forest roads is presented, based on the standard engineering properties of cross sections and the location-specific parameters of terrain slope and vegetation information. The model assumes six main cost elements of clearing operations, embankment, pavement, grading, culverts and ditch for total construction cost calculation. To validate the performance, the outputs of the model were compared with the experts’ prediction for an existing forest road project in a mountain condition. The final result of the research showed that the model could estimate total cost of road construction in an accuracy range of ±6.5%. The results of the validation process showed a 66.51% underestimate for clearing operation, 3.56% underestimate for embankment, 3.85% underestimate for surfacing, 3.32% underestimate for culverts, 20.54% underestimate for ditch excavation, and 22.33% overestimate for grading of the cut slope and travel way. According to the reasonable estimation for total cost, the model could be applied as an evaluation function in finding the optimized layout of a forest road network.