Fig 1.
Relationship between the existing building and foundation pit.
(a) Foundation pit adjacent to NG. (b) Foundation pit adjacent to the CFRLP.
Fig 2.
Schematic diagram of the rotation of the retaining structure.
Fig 3.
Annotated photos of the model box.
(a) Front of the model box. (b) Back of the model box.
Fig 4.
Particle-size distribution curve of the backfill.
Fig 5.
Direct shear test results of the sand.
Fig 6.
Triaxial test results of the sand.
Table 1.
Basic properties of the backfill.
Fig 7.
Direct shear test results from the interface of the rigid pile-soil.
Fig 8.
Direct shear test results from the interface of the flexible pile-soil.
Fig 9.
Photographs of the model pile.
(a) Rigid pile. (b) Flexible pile.
Fig 10.
Diagram of the CFRLP and sensors (unit: mm).
(a) Planform. (b) Side view.
Fig 11.
The photograph of the calibration devices.
Fig 12.
Photograph of installing the piles.
Fig 13.
Photograph of the layout of the loading plate and lifting jack.
Fig 14.
Schematic diagram of the pile-soil load-sharing principle of composite foundation.
Fig 15.
Displacement gauge for measuring the displacement of the movable rigid retaining structure.
(a) Displacement gauge for measuring the top displacement of the retaining structure. (b) Displacement gauge for measuring the displacement of the bottom of the retaining structure.
Fig 16.
Load-settlement curves for the NG and CFRLP.
Table 2.
The surcharge load acting on the loading plate of the NG and CFRLP.
Fig 17.
Pile-soil stress ratio and load-sharing ratio of the CFRLP due to applying surcharge.
(a) Pile-soil stress ratio for different surcharge loads. (b) Load-sharing ratio for different surcharge loads.
Fig 18.
The additional lateral earth pressure acting on the retaining structure adjacent to the CFRLP for different surcharge loads.
Fig 19.
Additional lateral earth pressure for a surcharge load of 89 kPa acting on the soil.
Fig 20.
The normalized height of the application of the lateral earth pressure for different surcharge loads.
Fig 21.
Pile-soil stress ratio and load-sharing ratio of the CFRLP due to the rotation of the retaining structure.
(a) Pile-soil stress ratio for different displacements of the top of the retaining structure. (b) Load-sharing ratio for different displacements of the top of the retaining structure.
Fig 22.
The additional lateral earth pressure adjacent to the CFRLP for different displacements of the top of the retaining structure.
Fig 23.
The lateral earth pressure at different depths for different displacements of the retaining structure.
Fig 24.
Schematic diagram of the rupture surface.
Fig 25.
The additional lateral earth pressure values for different displacements of the top of the retaining structure.
(a) 2 mm. (b) 6 mm. (c) 10 mm.
Fig 26.
The normalized height of application of the lateral earth pressure for different displacements of the top of the retaining structure.
Fig 27.
Arrangement of the numerical model.
Table 3.
Material properties used in the FEM analysis.
Fig 28.
Comparison of the load-sharing ratio for different surcharge loads.
Fig 29.
Comparison of the load-sharing ratio for different displacements of the retaining structure.
Fig 30.
Comparison of the lateral earth pressure when the surcharge load is 135 kPa.
Fig 31.
Comparison of the lateral earth pressure when the displacement of the retaining structure is 10 mm.
Fig 32.
Comparison of the lateral earth pressure for different elastic modulus values for flexible piles.
Fig 33.
Comparison of the lateral earth pressure for different lengths of flexible piles.
Fig 34.
Comparison of the lateral earth pressure for different wall-soil friction angles.