The various factors to be considered for pavement design are given bellow

  •  Design wheel load

  •  Subgrade soil

  •  Climate factors

  •  Pavement components material

  •  Environmental factors

  •  Special factors in the design of different types of pavements

Design wheel load

The thickness design of pavement primarily depends upon the design wheel load. Higher wheel loads need thicker pavement, Provided other design factors are the same. While considering the design wheel load, The effect of total static wheel load, Multiple wheel load assembly, Contact pressure, Load repetition and the dynamic effect of loads are taken into consideration.

Subgrade

The properties of the soil subgrade are important in deciding the thickness requirements of pavements. A subgrade with lower stability requires thicker pavement to protect it from traffic load.

Climatic factor

Rainfall affects the moisture conditions in the subgrade and the pavement layers. The daily and seasonal variation In the temperature has a role in the design and performance of the rigid and bituminous pavements.

Pavement component material

The stress distribution of the payment component layers depends on the characteristics of the material used. The fatigue behaviour of these materials and their durability under bad weather conditions also keep in consideration.

Environmental factors

Environmental factors like height of embankment, Its foundation details, Depth of cutting, Depth of subsurface water table also affect the performance of the pavement.

Special factor

In the case of semi-rigid pavement materials, the formation of shrinkage cracks, The cracks patterns and their mode of propagation and the fatigue behaviour of hair cracks under adverse conditions are studied before arriving at a rational method of design the semi-rigid pavement.