Traffic Index Calculator

Calculate Traffic Index



Formula

The formula to calculate the Traffic Index (TI) is:

\[ TI = 9.0 \left( \frac{ESAL \cdot LDF}{10^6} \right)^{0.119} \]

Where:

Traffic Index Definition

The Traffic Index (TI) is a measure used in pavement design to estimate the load-carrying capacity of a pavement structure. It is calculated based on the cumulative number of 18-kip equivalent single axel loads (ESAL) and the lane distribution factor (LDF). The TI helps in determining the appropriate thickness and materials for pavement layers to ensure durability and performance over the design life of the pavement.

Example Calculation

Let's assume the following values:

Using the formula to calculate the Traffic Index (TI):

\[ TI = 9.0 \left( \frac{5000000 \cdot 0.75}{10^6} \right)^{0.119} \approx 9.0 \left( 3.75 \right)^{0.119} \approx 10.53 \]

The Traffic Index (TI) is approximately 10.53.