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Flexible Pavement Thickness Calculator

Compute the required flexible pavement structural number using the AASHTO 1993 empirical design method. Used by pavement engineers to size asphalt road sections for a given traffic load, subgrade strength, and reliability level.

Design ESALs (applications)

Reliability Level

Subgrade CBR (%)

Serviceability Loss

Fill in the required fields to see your result.

Civil

Flexible Pavement Design Calculator

Calculate the required asphalt pavement layer thickness based on traffic loading (ESALs), subgrade strength (CBR), design reliability, and climate zone using the AASHTO flexible pavement method. Used by highway and airport pavement engineers.

Design ESAL (millions) (million)

Subgrade CBR (%)

Design Reliability

Climate Zone

Terminal Serviceability Index

Fill in the required fields to see your result.

Key differences

	Flexible Pavement Thickness Calculator	Flexible Pavement Design Calculator
Category	Civil	Civil
Inputs required	4	5
Result	Structural Number Required (SN)	Total Pavement Thickness (mm)
What it does	Compute the required flexible pavement structural number using the AASHTO 1993 empirical design method. Used by pavement engineers to size asphalt road sections for a given traffic load, subgrade strength, and reliability level.	Calculate the required asphalt pavement layer thickness based on traffic loading (ESALs), subgrade strength (CBR), design reliability, and climate zone using the AASHTO flexible pavement method. Used by highway and airport pavement engineers.