Dr Greg Arnold (CV click here) is the Director of Pavespec Ltd which started in 2003 with the first project to complete the Mass Limits Study at CAPTIF for Transit New Zealand.  This report has since been published on the Land Transport NZ website, titled Effect On Pavement Wear Of An Increase In Mass Limits – Concluding Report. 

Hot of the press! - Now operating in Australia go to the contacts page for information. Check out some typical Repeated Load Triaxial results for a TNZ M4 Basecourse and a GAP40 with and without cement - click here - ; Article in Quarry and Mining provides some background on Repeated Load Triaxial testing - click here - Pavespec Ltd was successful in obtaining 2007/08 Land Transport NZ research funding - click here for more details.

New Test! - Flexural Beam Fatigue and Breakage Tests - obtain flexural modulus and estimate of fatigue life - for an example - click here.  Great test for pavement design to ensure cracking does not occur.

Recent developments of Pavespec Ltd include the purchase of a Repeated Load Triaxial (RLT) apparatus which has tested a significant number of pavement aggregates for various quarry owners and Transit New Zealand.  Pavespec Ltd RLT apparatus is currently placed in Client laboratories to take advantage of a ready supply of aggregates, client staff to assist in material development and to use the other necessary laboratory equipment needed for the RLT testing. 

Dr Greg Arnold completed a 4 year doctorate at the University of Nottingham in England on developing a RLT test to predict rutting in granular materials.  Based on this experience he assists with the RLT testing and undertakes rut depth predictions using Finite Element modelling using the RLT data.  This experience has enabled Dr Arnold to refine and validate the rut depth prediction method and build up a database of RLT test results of aggregates throughout New Zealand. 

Repeated Load Triaxial Testing (RLTT) applies repetitive loading on cylindrical pavement materials for a range of specified stress conditions, the output is deformation (shortening of the cylindrical sample) versus number of load cycles (usually 50,000) for a particular set of stress conditions.  Multi-stage RLT tests are used to obtain deformation curves for a range of stress conditions to develop models for predicting pavement rutting.

Effectively RLTT is an on road test but in the laboratory and enables the proof testing/rut depth prediction of any new and existing pavement materials such as: granular; basecourse; waste materials; alternative materials; modified aggregates; stabilised aggregates; modified quarry overburden materials; recycled materials.  Pavespec Ltd is currently working with Transit NZ to introduce the RLTT into their specifications for Basecourse (TNZ M/4).