A TBM advances by thrusting against the built segments through an array of cylinders around the circumference. This thrust is a design...

Tunnel is a place where size matters. As a tunnel gets bigger in diameter comes a raft of challenges, some construction related, some...

This blogpost shares a few tips about modelling from personal experience

What is slurry used in TBM tunnelling? The slurry used in TBM tunnelling is basically a water-based suspension fluid with added solids...

Why slurry can support tunnel face? The reason why slurry can be used as an effective medium of face support, is because of the ‘filter...

Once the TBM gets started, it usually stops from time to time for a procedure called ‘face intervention’

For tunnelling operations in self-standing ground, three arch-types of TBMs can be used: open, single shield and double shield

Annulus grouting (also called back grouting or tail-skin grouting) is the grouting around the tunnel annulus – the backfilling of the gap...

main consideration factors around the segment thickness, radial length and longitudinal length

pros and cons between EPB TBMs and slurry TBMs under specific scenarios of consideration

This blog will complete this series by discussing some practical uses of the Convergence-Confinement theory

the in-situ stress of the ground will be shared between the ground itself and the supporting structure once the tunnel is done

What convergence and what confinement? Convergence-Confinement is a well-known theory in tunnelling, and widely applicable regardless of...

Selecting the ‘right’ TBM is all about maximising efficiency and minimising risk

Instrumentation and monitoring is an essential link of risk management in the cycle of design and construction

groundwater is a thorny problem for almost all underground constructions

This post is a study note based on various sources rather than professional advice, and may not be reflective of the most up-to-date...

In the underground world, being apparently accurate in the calculation process is usually meaningless.

This blog post outlines the overall fire engineering approach and touches on some basic principles.

the membrane is a delicate thing and requires a lot of careful detailing and handling.