His research interests include 3D printing of concrete, low carbon concretes, geopolymer concretes, use of phase change materials in construction and monitoring the performance of geopolymer concrete in the field. He is also involved in several consulting projects related to concrete technology and structural design.

He was Associate Professor of Civil Engineering at Monash University (1988-2009), commencing at Swinburne University of Technology in 2010.

Jay Sanjayan chaired the editorial board of Concrete in Australia and was a member of the editorial board of Construction Materials Journal, and Materials and Structures. He was Honorary President of RILEM (International Union of Laboratories and Experts in Construction Materials, Systems and Structures), and Chair of Concrete 2015, the 27th Biennial Conference of the Concrete Institute of Australia.

He has extensively published in the areas of geopolymer concrete, fire resistance of concrete, concrete materials technology and design, and his publications have received over 3,600 citations.