UK highways agency deflection method

The procedure for determination of the asphalt overlay consists of the following steps  

Relevant information about PANDEF or HAPMS can be found in Highways Agency (2008b). 

Highways Agency (2008a) recommends strengthening by overlay or partial reconstruction to be designed to extend the pavement life for a further 20 years. This procedure is known as pavement strengthening/upgrading. 

Highways Agency (2008a) also recommends that asphalt overlay design should not be based on deflection data alone, since deflectograph analysis does not take into account all factors related to pavement performance. 

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