5. Life cycle economic and environmental impact assessment analysis

#### 5.1 Life cycle cost analysis

RealCost, an LCCA software developed by the US federal highway administration, has been recognized and used in a number of states in the United States, becoming a widely recognized LCCA evaluation software. RealCost's LCCA method divides the life cycle cost into two parts, owner cost and user cost [31].

#### 5.1.1 Owner cost

The owner cost is the cost borne by the operator of the pavement. In the range of life cycle, it includes the initial construction cost, maintenance cost, and pavement management cost. The economic costs associated with these processes are attributed to the owner's costs, which can be calculated by the budget method. It must be noted that the calculation range is the life cycle of the road, so it is necessary not only to calculate the economic cost of the whole process of construction acceptance but also to estimate the economic cost of daily maintenance, rehabilitation, and recycling after the road is put into use as well as the economic value in the end of the road life cycle. Here is a simple example of how this economic value is calculated:

Suppose that the life cycle economic cost of two different road schemes needs to be evaluated and the time range of evaluation is 30 years. If one of the roads just reaches its service life in the 30th year, then the second kind of residual value is 0. If one of the highways is reconstructed in year 28 and will remain in use until year 35 to reach its useful life, the size of the second type of remnant is.

$$(\text{35-30})/(\text{35-28}) \times \text{the cost of the road rehabilitation} \tag{1}$$
