Measured Analysis on Surface Deformation and Influence of Cutter Torque for Twin Shield Tunnelling in Silty Sand

Table 3

Distribution of loss rate in soft soil region in Hangzhou Metro Line 2.

Soil loss rate	0.2∼0.5		0.5∼0.8		0.8∼1.2		Average value
Range (%)	Number	Proportion (%)	Number	Proportion (%)	Number	Proportion (%)
Former line	7	58.33	4	33.33	1	8.33	0.49
Latter line	6	42.86	6	42.86	2	14.28	0.61
Total	13	50.00	10	38.46	3	11.54	0.55