Since 2000, our Long Term Pavement Performance programme (LTPP) has been helping us to understand how our state highway surfaces perform. And we're building a picture of how pavements will perform in future through the use of the Deighton's Total Infrastructure Management System (DTIMS).
Covering 139 sites (71 on state highways, 68 on local roads), the LTPP survey data collection project provides detailed pavement performance information on roads with various characteristics. We collect this information – including on traffic, construction, climatic environment, age and condition – by accurately measuring carefully selected sections of road each year.
These survey results provide accurate, repeatable measures of rutting, roughness, texture and surface condition. We feed this data into the DTIMS deterioration models to improve their accuracy in predicting the future performance of the pavement. We also use the LTPP data to ensure the SCRIM+ vehicle provides reliable network-wide data of pavement condition, mainly on state highways.
To enable us to better understand the way our roads will perform in the future, we use the DTIMS to predict how much surfacing is going to need renewing, how much pavement length needs strengthening we will need to do over the next 10 years and the funding implications, for our state highway plans.
Principal Pavements Engineer
NZ Transport Agency
Private Bag 6995
Ph: +64 4 894 6256