Design

Pavement Utility Cuts

Appendix A. Sample Degradatation Fee Calculation

This appendix contains a sample method of computing the pavement degradation fee for the effect of utility cuts on the pavement structure. This calculation is comprised of four steps, calculating an appropriate degradation fee per unit area:

• Calculate the future cost of rehabilitation.
• Calculate the equivalent uniform annual cost (EUAC) of future rehabilitation for new design life.
• Calculate the value of the EUAC for remainder of original design period.
• Calculate the present value of the future EUAC.

Step 1: Calculate the future cost of rehabilitation

F_repair = P_repair(1 + i)^{N RL} (1)

where:

F_repair = future cost of P_repair

P_repair = present day pavement repair cost

i = discount rate

N_RL = number of years to end of service life, after cut is made

Step 2: Calculate the equivalent uniform annual cost (EUAC) of future rehabilitation for new design life.

where:

A = Annual cost of rehabilitation (over its design life) performed at end of current (adjusted) service life

N_d = Design life of new rehabilitation

Part 3: Calculate the value of the EUAC for remainder of original design period.

where:

P_rehab = cost of portion of rehabilitation that will carry the pavement section to the end of the original design life

L_L = lost life due to utility cut

Part 4: Calculate the present value of the future EUAC.

where:

P_rehab = Cost of rehabilitation earlier than expected

PLRC = Present value of future rehabilitation (P_rehab) to carry pavement to end of original design life.