Temperature

The temperatures at different depths of the pavement structure, over the simulation period, are first calculated. The temperature at the surface is read from the EICM database (with 30 years of data) and the temperatures at different depths are  calculated using the surface temperature, a constant deep soil temperature and the previous temperatures. It is done using a 1-D Galerkin Finite Element formulation with a finite difference time step. Calculation over the full 30 years is used to initialize the system.

Surface temperatures have been pre-calculated for each hour of a 30 year period for all climate zones and different pavement structures in California.  The values are stored in a database. Calculation over 30 years is used to initialize the system. More details of the model for temperature calculation can be found in the subsection on Hear Transfer.

If the temperature database is not available, CalME can calculate the temperature from the yearly mean, yearly range and daily range temperatures using the following equations:

where tYearMean is the mean yearly surface temperature, degree Celsius,

 YearRange is the yearly range in surface temperature, degree Celsius,

 DayRange is the daily range in surface temperature, degree Celsius,

 z is the depth in mm, and

 h is the hour counted from the start of the year.