The total cost (C_T) of maintaining or rehabilitation of a pavement is determined by (Yang & Al-Qadi, 2005):

where C_M&R represents the agency cost. This typically consists of fees for engineering, contract administration, construction, maintenance and rehabilitation, etc... C_U is the user cost which includes queue delay cost, moving delay costs, fuel costs, and work zone accident costs. The Life-Cycle-Cost Analysis (LCCA) should be used as an analysis technique to asssess the over all long-term economic efficiency of different design alternatives.

This calculator, however, only determines the installed material cost for different flexible pavement cross-sections that meet the same target structural number. Structural Number (SN) is used to quantify the structural strength of a pavement required for a given combination of soil support, total traffic, reliability, and serviceability level. The required SN is converted to actual thicknes of surfacing, base and subbase, by means of appropriate layer coefficients, and drainage modifiers representing the relative strength and drainage quality of the construction materials. The design equiations used are as follows:

where

Case 1	Case 2	Case 3	Case 4
Images not necessarily drawn to scale.