Concrete Spalling Detection for Metro Tunnel from Point Cloud Based on Roughness Descriptor

Table 2

Basic information of concrete spalling patches.

No.	Mileage [m]	Spalling patches	Images	Spalling area [m^2]	Spalling depth [m]
J1	176			0.0191	0.112
J2	176			0.0276	0.126
J3	177			0.0377	0.195
J4	178			0.0340	0.099
J5	177			0.0384	0.129
J6	177			0.0681	0.083
J7	193			0.0249	0.091