Multiparameter Inversion Early Warning System of Tunnel Stress-Seepage Coupling Based on IA-BP Algorithm

Table 6

Residual calculation results.

Experimental factors	Residual
	Elastic modulus E (GPa)	Cohesion c (MPa)	Poisson’s ratio μ	Internal friction angle φ (°)
Test 1	−1.554	0.032	0.046	1.213
Test 2	0.723	−0.095	0.008	1.092
Test 3	0.703	−0.116	−0.004	−0.768
Test 4	−0.001	0.000	−0.001	−0.013
Test 5	−0.413	0.032	−0.005	0.314
Test 6	3.064	−0.002	0.003	0.187
Test 7	0.001	0.000	0.000	0.001
Test 8	−1.386	0.211	0.002	−1.894
Test 9	0.004	0.016	−0.048	2.019