A Case Study of Thaumasite Sulfate Attack in Tunnel Engineering

Table 4

Test results of marlstone [26].

No.	Drilling number	Locations	Free expansion rate Fs (%)	Expansion force Pp (kPa)	Saturated water absorption rate ωsr (%)	Natural compressive strength (MPa)	Saturated compressive strength (MPa)	Softening coefficient, δ
1	ZK5	K34 + 953	—	1.5	5.2	26.9	22.0	0.818
2	ZK19	K35 + 370	0.001	4.13	6.00	20.4	16.2	0.794
3	ZK4	K34 + 822	0.006	0.99	4.60	12.0	9.0	0.75
4	ZK15	K35 + 155	0.094	20.6	2.90	29.6	21.5	0.726