What is pile foundation engineering?

My opinion:

The full name of pile foundation is called pile foundation, which is one of the foundations (in the direction of civil construction, foundations are generally divided into: independent foundation, strip foundation, raft foundation, phase foundation, pile foundation, etc. In the direction of road and bridge, it can be generally divided into: U-shaped enlarged foundation, pile foundation, etc.), and the main function of pile foundation is to transfer the load to the bearing layer.

The following is the concept of

:

consists of a foundation pile and a cap connected to the top of the pile. If the pile body is completely buried in the soil, and the bottom of the pile cap is in contact with the soil, it is called low pile cap pile foundation; If the upper part of the pile body is exposed to the ground and the bottom of the cap is above the ground, it is called high cap pile foundation. Building pile foundation is usually a low cap pile foundation. Pile foundation is widely used in high-rise buildings.

Features:

(1) Piles are supported on hard (bedrock, dense gravel layer) or hard (hard plastic cohesive soil, medium dense sand, etc.) bearing layers, and have high vertical single pile bearing capacity or pile group bearing capacity, which is enough to bear all vertical loads (including eccentric loads) of high-rise buildings.

(2) The pile foundation has great vertical stiffness of single pile (end-bearing pile) or group stiffness (friction pile), which will not cause excessive uneven settlement under the influence of self-weight or adjacent loads, and ensure that the inclination of the building does not exceed the allowable range.

(3) With the huge lateral stiffness of single pile (large-diameter pile) or pile group foundation and its overall overturning resistance, it can resist the horizontal load and moment load caused by wind and earthquake and ensure the overturning stability of high-rise buildings.

(4) The pile passes through the liquefiable soil layer and is supported on the stable solid soil layer or embedded in the bedrock. Under the condition that the shallow soil layer is liquefied and subsidence is caused by the earthquake, the pile foundation still has enough compressive and uplift bearing capacity against the deep solid soil layer, thus ensuring the stability of the high-rise building without excessive subsidence and inclination. Commonly used pile types mainly include precast reinforced concrete piles, prestressed reinforced concrete piles, bored piles, hand-dug piles, steel pipe piles, etc., and their applicable conditions and requirements are stipulated in the Technical Specification for Building Pile Foundation.