Predictive Analysis of Settlement Risk in Tunnel Construction: A Bow-Tie-Bayesian Network Approach

Table 10

Analysis of event occurrence.

Symbol	Event
OE1	Excessive surface settlement
OE2	Grouted cutter head and shield, excessive surface settlement, and minor property damage
OE3	Minor surface collapse and property damage
OE4	Moderate surface collapse, major property damage, and minor casualties
OE5	Excessive surface settlement
OE6	Grouted cutter head and shield, moderate surface collapse, and minor property damage
OE7	Moderate surface collapse and major property damage
OE8	Severe surface collapse, major property damage, and major casualties