Muuga PHAJ heakskiidetud KSH programm - Energiasalv

1. PREGROUTING
• Grouting holes 10-20 m are
drilled into water bearing zones
(fracture zone)
• Cement grout is pumped into
the zone to prevent water
leakage
• Grouting decision
• Water loss test -> Lugeon
value L/min.m.P
2. DRILLING
• Drilling holes are done for
excavation (length 3-6 m)
• The rock is removed by
blasting
• Different drilling patterns are
used depending on the tunnel
profile and rock quality
3-6 m
3