Because the strength and deformation resistance of piles are better than that of soil, the bearing capacity and modulus of composite foundation are also better than that of original soil, thus reducing deformation and improving bearing capacity.
During the construction of loose wooden piles, the original soil at the pile hole is forced to squeeze laterally by hammering, which improves the soil density in a certain range around the pile and plays a role in compaction. The compaction effect of pine wood pile composite foundation on the soil between piles in construction makes the soil between piles compact, thus improving the bearing capacity and reducing the compressibility of the soil between piles.
Extended data:
The composite foundation of granular pile replaces the low modulus and low strength soil with the same volume as the pile. When subjected to external load, the stress in the foundation is redistributed according to the pile-soil stress ratio. The stress gradually concentrates on the pile, and the stress of the soil around the pile decreases accordingly, and most of the load is borne by the pine pile.
The horizontal resistance of foundation soil in silt area is very small, and the upper end of loose pile group is prone to overall horizontal displacement, which damages ground facilities; Therefore, even if the horizontal load of earthquake is not considered, a layer of stone should be laid between loose piles to improve the horizontal stiffness of pile groups as much as possible. Stone layers can only be laid manually, and pine stakes should be squeezed as tightly as possible.
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