Experimental Investigation on the Influence of Regional Concrete Spalling on Shield Tunnel Segments

Table 1

Statistical results of the length, width, and depth of spallings.

Characteristic value	Length (mm)	Spalling angle (°)	Width (mm)	Depth (mm)
Maximum value	3190	66.46	230	118
Minimum value	60	1.25	50	12
Average value	1443	30.06	183	94