Tunnel Support Failure: Arching Stress Simulator (2D)

Ground & Support

Overburden depth 14 rows

Rock mass quality (RMR) 50

Support spacing every 4

Support capacity 55

Live Readouts

State · Static

Props intact

6 / 6

Abutment factor

1.0×

Sim time

0.0 s

Crown stress

How it works

This is a companion build to the 3D "Tunnel Collapse Simulator", modelling the same real mechanism — progressive tunnel-roof failure under overburden load — with a different technique: instead of a triggered rigid-body panel/debris animation, this is a cellular stress-redistribution (arching) model. Each column of rock carries its own weight downward; where the tunnel opening removes material, that column's load cannot go straight down, so it diffuses sideways into neighbouring rock and concentrates on the nearest solid path — the classic geotechnical arching effect.

Overburden depth sets how much rock weight bears down on the opening before it ever reaches the roof line.
Rock mass quality (RMR) controls how well the rock can transfer shear sideways — better rock forms a tighter, more efficient arch that keeps load off the supports; poor rock barely diffuses load at all, dumping nearly all of it straight onto the nearest prop or pillar.
Support spacing sets how many roof props share the opening's width — denser spacing means each prop carries less.
The abutment factor readout shows how many times the natural overburden weight is now concentrated on the rock pillar beside the opening — a direct, real stress-concentration number engineers watch for.
Running the loading test slowly degrades effective support capacity (representing blast vibration or time-dependent creep); once a prop's load exceeds its capacity it fails, dumping its share onto its neighbours — which can cascade past the collapse threshold into a full roof fall.

stress heatmap · not to scale

Low stress Elevated Overloaded Failed / debris