Investigation of the Permanent Deformation Behaviour of Hot Mix Asphalt under Controlled Confining Pressure Utilising the Modified Wheel Tracker by ABHIRUP Basu Roy Chowdhury, M.Sc. under the supervision of Prof. Mofreh Saleh, Department of Civil and Natural Resources Engineering & Dr. Miguel Moyers-Gonzalez, School of Mathematics and Statistics A dissertation submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy in Civil Engineering Department of Civil and Natural Resources Engineering University of Canterbury Christchurch, New Zealand March 2022 UNIVERSITY OF CANTERBURY