How many types of piles are there? There are several types of piles for pile foundation engineering

Foundation piles are classified according to regulations: 1. According to the classification of bearing characteristics: friction piles, end-bearing piles; 2. Classification according to pile forming method:

non-extruded piles, partially extruded piles, extruded piles; 3. Classification according to pile diameter: small diameter pile d 250mm, medium diameter pile 250mm d 80mm, large diameter pile d 800mm.

Concrete mixing piles Concrete cast-in-place piles.

Both.

If it is divided according to the principle of foundation force, there are two kinds, one is friction pile.

There is also a type of bearing pile. If it is divided according to the way of construction, it can also be divided into two kinds, one is prefabricated piles, which drive the reinforced concrete piles that have been poured directly into the ground, and the other is poured on site. If it is divided according to size, it can be roughly divided into three types, respectively, small piles.

Medium piles and large piles, when the diameter of the pile foundation exceeds 80 cm, it belongs to large piles.

Precautions for pile foundation construction.

Be sure to wear a hat and take appropriate precautions. At the same time, a comprehensive inspection should be carried out for the equipment that needs to be used, and if a fault is found, it should be repaired in time to ensure that the product is not a problem before use.

Pay attention to the guardrails around the four sides of the pile hole. And also to set up obvious signs, so that can play the role of prompt and warning, in addition, during construction, if you encounter the condition of water seepage on the well wall, you must discharge the water as soon as possible, during the construction, keep a certain distance between the various pile foundations, after the construction, clean up the garbage in time.

There are two kinds of piles for pile foundation engineering, prefabricated piles and cast-in-place piles.

1. Prefabricated piles.

Precast piles refer to prefabrication on the spot at or near the piling site, and shorter piles can also be produced in the prefabrication plant. It is characterized by being able to withstand large loads, strong and durable, fast construction speed, and has a great impact on the surrounding environment. The construction procedures are prefabrication, transportation, stacking, and pile sinking.

The pile is driven into, pressed into or vibrated into the soil with pile sinking equipment, and the prefabricated piles that use more are mainly concrete prefabricated piles and steel piles.

2. Cast-in-place pile.

Cast-in-place piles are first drilled on the construction site, and when the required depth is reached, the rebar is placed into the poured concrete. The advantage is that the construction difficulty is low, especially the manual digging pile, which can not be limited by the number of machinery, and all pile foundations are constructed at the same time, which greatly saves time. The disadvantage is that the bearing capacity is low and the material is expensive.

Matters needing attention in pile foundation engineering:

1. When designing pile foundation engineering, we must first choose a reasonable one to ensure the safety of the whole building, and at the same time take into account its functionality, and make full use of the underground space in combination with geological conditions.

2. At the same time, when choosing the type of piling, it is also necessary to consider whether the building will have the problem of settlement and whether it can meet a certain bearing capacity.

3. Regarding the horizontal bearing capacity of the pile foundation, it will be affected by various factors. For some high-rise buildings, the foundation must have the ability to resist horizontal loads.

The classification methods of piles include bearing, pile forming method, construction method, and formation method. When classifying by bearing, piles can be divided into friction piles and end-bearing piles, which are mainly determined according to the different parts of the bearing force. According to the classification of pile formation methods, it can be divided into two categories: driven piles and cast-in-place piles, when the friction is relatively high and the surrounding roughness needs to be maintained.

Piles can be classified according to their bearing capacity, which can be divided into friction piles and end-bearing piles. Friction piles are the main loads that are borne by the lateral resistance of the piles when the bearing capacity reaches the ultimate state. End-bearing piles are the top of the pile that carries the main load when the load capacity reaches its limit.

According to the method of piling, it can be divided into three types: non-extruded piles, partially extruded piles, and extruded piles. In the process of forming piles when non-extruded piles, the same soil volume as the pile is dug out, and when some squeezed piles are in the process of forming piles, the squeezing effect is slightly caused, and the squeezing piles are formed in the process of forming piles, and all the soil is squeezed out to form.

According to the construction method, it can be divided into bored shrub pile, immersed pipe cast-in-place pile, manual digging cast-in-place pile, and mechanical digging cast-in-place pile. Among them, the methods include positive circulation rotation method, reverse circulation rotation method, auger drilling rig hole forming method, etc., the density of wooden piles is larger, and it can be tightly gathered in the soil layer to consolidate the entire foundation.

According to the formation method of pile, it can be divided into driven pile and cast-in-place pile. Driving piles is the use of machinery to drive wooden stakes into the soil, and the friction is relatively high, so it is necessary to make the perimeter of the wooden stakes more rough. Cast-in-place piles mainly play the role of fixing the foundation through the method of casting.

The common classification of pile foundation is mainly to describe and evaluate the quality of pile foundation.

Class I: The pile body is complete.

Class II: The pile has slight defects, which does not affect the normal play of the bearing capacity of the pile structure.

Category III: The pile has obvious defects, which have an impact on the bearing capacity of the pile structure.

Category IV: Serious defects in the pile.

Integrity is the dimensional variation of the pile, the compactness and continuity of the material.

Pile defects refer to pile fractures, cracks, mud inclusions, cavities, honeycombs, looseness, etc.

Class IV piles should be treated with engineering.

1. According to the principle of force on the foundation, it can be roughly divided into friction pile and bearing pile.

1. Friction pile:

It uses the friction between the stratum and the foundation pile to carry the structure, and can be divided into pressure pile and tensile pile, which is generally used for the formation without a hard bearing layer or a deep bearing layer.

2. End bearing pile:

The foundation pile is located on the bearing layer (rock plate) so that the structure can be loaded.

Second, according to the construction method, it can be divided into prefabricated piles and cast-in-place piles.

1. Prefabricated piles.

The prefabricated reinforced concrete piles are driven into the ground by means of a piling machine. The advantage is that the material is saving, the strength is high, and it is suitable for buildings with higher requirements, and the disadvantage is that the construction difficulty is high, and the construction time is long due to the limitation of the number of machinery.

2. Cast-in-place pile.

Holes are first drilled in the construction site, and when the required depth is reached, the rebar is placed into the poured concrete. The advantage is that the construction difficulty is low, especially the manual digging pile, which can not be limited by the number of machinery, and all pile foundations are constructed at the same time, which greatly saves time, and the disadvantage is that the bearing capacity is low and the cost of materials.

Detection technology of pile foundation:

1) Static load test:

The static load testing technology of pile foundation is developed with the increasing use of pile foundation in architectural design. After the founding of the People's Republic of China, the static load testing technology of pile foundation has been gradually developed. After the 80s of the 20th century, with the pace of reform and opening up, the scale of capital construction has increased year by year, especially the wide application of cast-in-place piles in engineering, and China's pile foundation static load testing technology has also entered a new period of development.

2) Low strain treatment:

In the 80s of the 20th century, the low-strain method based on the wave equation entered a period of rapid development, and various low-strain methods have achieved many valuable results in basic theory, mechanism, instrument research and development, field testing and signal processing technology, engineering pile and model pile verification research, and practical experience accumulation.

3) High strain applications:

China's high strain dynamic pile test method research is from the mid-to-late 80s of the 20th century, to the early 90s there are related software and hardware, the practical application effect has not been weaker than foreign countries, in the cast-in-place pile detection pile foundation dynamic measurement, domestic instruments and software have reached the international advanced level, some aspects show Chinese characteristics.

4) Acoustic Transmission Method:

The acoustic transmission method of concrete cast-in-place piles is developed on the basis of acoustic detection technology of structural concrete. By the 70s of the 20th century, acoustic transmission methods began to be used to test the integrity of concrete cast-in-place piles.

5) Drilling and coring method:

In the 80s of the 20th century, the borehole coring method was mainly used for the detection of bored piles, and it was also used to detect the construction quality of underground diaphragm walls in areas with mature technical conditions. The core drilling method is a detection method for micro damage or local damage, which has the characteristics of science, intuitiveness and practicality.

The above content refers to the encyclopedia pile foundation.

1. Friction pile:

1) Friction pile: In the ultimate state of bearing capacity, the vertical load of the pile top is borne by the resistance of the pile side, and the resistance of the pile end is negligible.

2) End-bearing friction pile: In the ultimate state of bearing capacity, the vertical load on the top of the pile is mainly borne by the resistance of the pile side.

2. End-bearing pile:

Wang Yuan 1) End-bearing pile: In the ultimate state of bearing capacity, the vertical load on the top of the pile is all borne by the resistance of the pile end, and the resistance on the side of the pile is negligible.

2) Friction end bearing pile: In the ultimate state of bearing capacity, most of the vertical load on the pile top is borne by the resistance of the pile end.