Engineering in Practice

Events and Activities

Webinar on Sustainable Asphalt Pavement Construction (Jointly organized by HKIE CVD and PolyU)

Technical Seminar:
Upcycling of Sewage Sludge Ash into Foaming Warm Mix Asphalt Additive for Sustainable Asphalt Pavement Construction

Date, time & venue

7 December 2022 (Wednesday), 17:00-18:00, Seminar via Zoom Meeting


Organized by

HKIE Civil Division and The Hong Kong Polytechnic University

Programme Highlight

Waste recycling/upcycling has become an important topic in highway and pavement engineering, because of its significant economic and environmental benefits. This presentation will start with a brief introduction to the green technologies developed in Hong Kong to recycle various types of wastes, such as reclaimed asphalt pavement, waste tyre rubber, and waste plastics, into pavement. Then, a recent study on converting sewage sludge ash into zeolite-based foaming warm mix asphalt additive, which can reduce the construction temperature of asphalt pavement by at least 20 oC without compromising its mechanical performance, will be presented. In the end, some remarks and discussions on recycling wastes into pavement will be provided.

*Please complete the on-line registration at





Free of Charge.


Dr. Zhen Leng is an Associate Professor and the Associate Director of the Research Center for Resources Engineering towards Carbon Neutrality at The Hong Kong Polytechnic University. He received his PhD degree in Civil Engineering from University of Illinois at Urbana-Champaign. His research interests mainly include sustainable and smart pavement materials and technologies, and nondestructive evaluation of transportation infrastructure. He currently serves as the President of ASCE Greater China Section, Vice President of Academy of Pavement Science and Engineering, a Co-opted Council Member of Hong Kong Institution of Highways and Transportation, a Director of International Association of Chinese Infrastructure Professionals and the Chair of the Asphalt Pavement Discipline of World Transport Convention. He is also an Editor-in-Chief of Journal of Cleaner Materials, an Executive Editor of Journal of Cleaner Production, and an Associate Editor of ASCE Journal of Materials in Civil Engineering, and Journal of Transportation Engineering, Part B: Pavements.

Registration & Enquiries

Please complete the on-line registration at The number of participants is limited to 500 on a first-come-first served basis. Priority will be given to members of the Civil Division.

Email registration will not be accepted. Successful applicants will be informed by email and provided a link to the Zoom Meeting at the designated time slot. Participants need to sign in using the membership no. and name entered at the time of registration. A CPD certificate will be issued 3 weeks after the seminar based on this membership no. and name.

For enquiries, please contact Mr. Alan Yan via email: