Combined Application of Optical Fibers and CRLD Bolts to Monitor Deformation of a Pit-in-Pit Foundation

Table 1

Distribution and characteristics of soil layers at the foundation pit.

Categories	Density (kg·m^−3)	Elastic modulus (Mpa)	Poisson’s ratio	Cohesive force (kPa)	Internal friction angle (°)	Depth range (m)
Clay	1900	25	0.29	55	19.4	0 to −1.81
Silty clay	1920	30	0.3	53	20.5	−1.81 to −10.94
Silty clay mixed with sand	1980	40	0.3	22	19.8	−10.94 to −21.71