Test: Flexible Pavement Design Method

There are three types of methods to design a flexible pavement they are empirical, semi empirical and theoretical method.

The strength of the soil sub grade is used to design the flexible pavement, because the sub base and base are more stronger than the sub grade, so design depends on sub grade only.

The design of pavement using stress strain approach is used in semi empirical method, which depends both on theory and graph.

CBR is a method of designing the flexible pavement by using the soil characteristics.

 The design charts are prepared based on the past experience hence they are not reliable, as it changes according to location.

 The minimum sample size of axle load considered in India is 20%.

The HCV are used to study the pavement design if their weight exceeds 3 tonnes.

 The maximum life span of an overlay design is 10 years, it may be also 5 years for small roads.

The most commonly used overlay is flexible over flexible, rigid over flexible and rigid over rigid are also used but flexible is the most preferred and used pavement.

The commercial vehicles per day are considered as 150 to 1500 for pavement design studies.