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

Table 4

Membership frequency of 23 mm/min belonging to the “normal excavation speed.”

Description	Number and membership
Number of rings	50	100	150	200	250	300	350
Membership counts	28	51	60	97	128	153	178
Membership frequency	0.56	0.51	0.4	0.49	0.51	0.51	0.51
Number of rings	400	450	500	550	600	650	715
Membership count	202	252	302	342	382	427	470
Membership frequency	0.51	0.56	0.61	0.62	0.64	0.66	0.66