SYNOPSIS

The MTR West Island Line is an extension of the existing MTR Island Line (ISL) of Hong Kong Island. The project involved the demolition and backfilling of 132 m of an existing Overrun Tunnel through complex geology beneath a densely-populated urban area in order to enable the subsequent excavation of the new running tunnel. The underground demolition works were completed using a bespoke tunnel dismantling machine (TDM). The TDM was assembled inside the existing tunnel and worked backwards to remove each ring of lining segments under 2.8 bar compressed air pressure, placing a sprayed concrete lining for temporary support and backfill of the remaining void left underground. This presentation will explain the TDM’s design, development, assembly and operation to complete the works and allow the realigned running tunnel to be completed successfully.


BIODATA OF SPEAKER

Mr SALISBURY Christopher David (B.Eng., FHKIE, RPE)

36 years post qualification experience in tunnel and heavy civil engineering design, construction and project management. Other experience includes design and construction of heavy civil infrastructure including stations, industrial buildings, deep basements, caverns, earth retaining structures and airport Infrastructure; Experience in the field of tunnel boring machine (TBM) design and manufacture and business administration. David is familiar with all international forms of contract and has specialised throughout his career in Target Cost and more recently NEC4 forms of contract. Certified NEC Professional a Fellow of the Hong Kong Institution of Engineers. He is currently an independent consultant specialising in consulting and risk management for tunnelling and major infrastructure works.

David is the secretary of the Hong Kong Tunnelling Society organizing meetings and lectures for over 15 years, he also helped organise two highly successful IMMM Tunnelling Conferences in Hong Kong in 2009 and 2015. He has sat on a number of committees and professional bodies related to the construction industry in Asia. He was the key author of the Hong Kong Geotechnical Engineering Office Report 298 “Ground Control for EPB TBM Tunnelling” published in 2014 and has been the author or co-author of over 20 technical publications.