SYNOPSIS

The Central Interceptor main tunnel is a 14.7-km-long, 4.5-m-diameter sewer tunnel currently under construction in Central Auckland. Upon its completion, it will provide additional capacity in the network to meet the planned population growth and development, ensure a more resilient wastewater system, and mitigate wet weather overflows. It will be New Zealand’s largest and longest bored wastewater tunnel. The single-pass tunnel lining is designed for a 100-year design life, consisting of 324.5-mm-thick concrete lining with an inner 3-mm-thick high-density polyethylene (HDPE) corrosion protection layer. The thickness of concrete lining includes a sacrificial concrete layer as per the Client’s Specification. This webminar will present the challenges, lessons learned and detailed considerations in designing the tunnel segmental lining from structural, geotechnical  and constructability perspectives. In addition, some recommendations based on observations and lessons learned from segmental lining production and installation will also be discussed for the improvement to similar future projects.


BIODATA OF SPEAKER

Dr. Sofren Leo Suhaendi

Dr Sofren Leo Suhaendi is an Associate | Deputy Tunnel Leader for Arup Singapore Pte Ltd. He has been involved in major infrastructure projects in Singapore, Southeast Asia and Australasia region. He has over 15 years professional experience encompassing analysis, design management, research & development and tender/procurement. His expertise is in Fibre Reinforced Concrete. He is one of the Working Group members contributing to the launching of SS674: 2021, Singapore Standard on Fibre Concrete – Design of Fibre Concrete Structures.