The Environmental factors that affect the pavement materials

The Environmental factors that affect the pavement materials

Environmental  factors  affect  the  performance  of  the  pavement  materials  and  cause various damages.  Environ-mental  factors  that  affect  pavement  are  of  two  types,        temperature and precipitation and they are discussed below:

Temperature

The effect of temperature on asphalt pavements is different from that of concrete pavements.

Temperature affects the resilient modulus of asphalt layers, while it induces curling of concrete slab. In rigid pavements, due to difference in temperatures of top and bottom of slab, temperature stresses  or  frictional  stresses  are  developed.  While  in  flexible  pavement,  dynamic  modulus  of asphaltic  concrete  varies  with  temperature.  Frost  heave  causes  differential  settlements  and pavement roughness. Most detrimental effect of frost penetration occurs during the spring break up period when the ice melts and subgrade is a saturated condition.

Precipitation

 The precipitation from rain and snow affects  the quantity of surface water in filtrating into the subgrade and the depth of ground water table. Poor drainage may bring lack of shear strength,pumping, loss of support, etc.