TAC BC Talk: “Old School” Tunneling: Open-Face Shield Tunneling to Overcome Challenging Ground Conditions
Event Details:
Date: April 28, 2026, 5:30 PM
Location:
Steamworks Brewpub – Uber Room
375 Water St., Vancouver, BC
Registration Cost:
$5 for members, $10 for non-members
About the Talk:
Open-face shield tunneling has been used to construct underground infrastructure since the late 1800s. While equipment and materials have advanced significantly, the fundamental design and construction methodology remains largely unchanged. After a long hiatus, open-face shield tunneling that utilized hand mining and mechanical excavation has seen renewed application on select projects, where a combination of unique challenges make other methodologies impractical.
This presentation provides an overview of shield tunneling and conventional shaft sinking; discusses how open-face shield tunneling can be applied in challenging geology; and summarizes lessons learned from projects that used shield tunneling to construct sewer force mains, gravity sewers, fish passage tunnels, and raw-water supply pipelines. Topics include ground depressurization, launch thrust reaction, tooling durability, boulder removal capability, muck handling issues, and productivity expectations (including learning-curve effects).
Biography:
Mr. Havekost is a Principal with Delve Underground, specializing in underground design and geotechnical engineering for a broad range of infrastructure projects. He earned an MS in Geotechnical Engineering from the University of California, Berkeley, and a BS in Civil Engineering from California Polytechnic State University, San Luis Obispo. His experience includes the evaluation, design, and construction of tunnels and shafts under challenging geotechnical and seismic conditions, with an emphasis on constructability. His project background includes direct support to contractors, providing construction engineering design services for open-face shield tunneling.
