Pine piles, piles made of pine, are mainly used to treat soft foundations, river embankments, etc. The soft soil foundation reinforced by pine piles is a composite foundation. The composite foundation is composed of natural foundation soil and pile body. The pine pile composite foundation is similar to other composite foundations. Compared with other trees, except for the different materials of the piles, they are similar. Pine trees are rich in turpentine, which can prevent groundwater and bacteria from corroding it, so it is called "flooded evergreen pine". Therefore, pine piles are suitable for groundwater levels. The following river slope protection projects. However, in areas where the groundwater level changes greatly or the groundwater is highly corrosive, pine piles should not be used.

Pine pile reinforced soft soil foundation is a composite foundation. The composite foundation is composed of natural foundation soil and pile body. Compared with other composite foundations, pine pile composite foundation has similarities except that the pile materials are different. Its reinforcement mechanism is as follows :

1. Supporting role of piles: The pine pile composite foundation replaces low-modulus, low-strength soil with the same volume as the piles. When subjected to external loads, the stress in the foundation is redistributed according to the pile-soil stress ratio. When the stress gradually concentrates on the piles At this time, the stress of the soil around the piles is reduced accordingly, and most of the load is borne by the pine piles. Since the strength and deformation resistance of the piles are better than those of the soil, the bearing capacity and modulus of the composite foundation formed are also better than those of the original soil, thus achieving reduction Small deformation and improved bearing capacity effect.

2. Condensation: During the construction process of pine piles, the original soil at the pile hole is forced to be squeezed laterally, which increases the density of the soil layer within a certain range around the pile and plays a squeezing effect. The pine pile composite foundation is under construction The squeezing effect on the soil between the piles makes the soil between the piles dense, thereby increasing the bearing capacity of the soil between the piles and reducing the compressibility.