Fig 1.
Punching shear failure mode.
Fig 2.
Double logarithmic spiral failure mode (The cave shifts to the right).
Fig 3.
Double logarithmic spiral failure mode (The cave shifts to the left).
Fig 4.
Prandtl destruction mode.
Fig 5.
Schematic diagram of double logarithmic spiral failure mode.
Table 1.
Geophysical param.
Fig 6.
Schematic diagram of pile group foundation layout.
Fig 7.
Monitoring diagram.
Table 2.
Monitoring results of AZK03 pile group foundation/mm.
Table 3.
Monitoring results of AZK08 pile group foundation/mm.
Table 4.
Monitoring results of AZK10 pile group foundation/mm.
Table 5.
Monitoring results of AZK11 pile group foundation/mm.
Table 6.
Monitoring results of AZK14 pile group foundation/mm.
Fig 8.
Model size diagram.
Fig 9.
Model diagram.
Fig 10.
Working condition diagram of karst cave no-offset.
Fig 11.
Working condition diagram of cave offset 4 m.
Fig 12.
Working condition diagram of cave offset 8 m.
Table 7.
Relevant mechanical param of piles and surrounding rock and soil.
Table 8.
AZK03 settlement data/mm.
Table 9.
AZK08 settlement data table/mm.
Table 10.
Mesh count and calculation results.
Fig 13.
Load–settlement curves of pile group foundations with different mesh element numbers.
Fig 14.
Load-settlement curve.
Fig 15.
Pile number arrangement diagram.
Fig 16.
Pile side friction curve under working condition I.
Fig 17.
Pile side friction curve under working condition II.
Fig 18.
Pile side friction curve under working condition III.
Fig 19.
Axial force curve under working condition I.
Fig 20.
Axial force curve under working condition II.
Fig 21.
Axial force curve under working condition III.
Fig 22.
Displacement cloud map of pile group condition III under uniformly distributed load of 600 kPa.
Fig 23.
Comparison of ultimate bearing capacity of pile groups under the condition of underlying offset cave.
Fig 24.
The cave with a 6 m offset from the pile end.
Fig 25.
The cave with 10 m offset from the pile end.
Fig 26.
Load-settlement curves for different distances between cave and pile end.
Table 11.
Analysis of calculation methods for the pile group effect.
Table 12.
Reference parameter table.
Table 13.
Parameter variables and pile end resistance QP.
Fig 27.
b-QP fitting plot.
Fig 28.
h/b-QP fitting plot.
Fig 29.
s/b-QP fitting plot.
Fig 30.
φ-QP fitting plot.
Fig 31.
c-QP fitting plot.
Table 14.
Sensitivity function and sensitivity factor.