How to calculate the pile cutting height, pile feeding depth and foundation bottom elevation of pref

The depth of the pile in the lower chamber is 500 from the design pile top to the outdoor floor height. Your basement is relatively deep, and it should be excavated first and then piled, so the pile feeding depth is designed to be as high as the top of the pile to the parking surface (raft.

Cushion bottom elevation) plus 500.

Pile cutting heads, prefabricated piles are generally calculated by the number, such as the AB type high-strength prestressed pipe pile.

If the fixed length is 12 meters, and the piling record is 20 meters, then it will be counted as a pile cutting head, and if the piling record is 24 meters, it will not be counted as a pile cutting head.

For example, the pile is 12 meters, and the piling record is 20 meters, two piles should be used, 12 * 2-20 = 4, then 4 meters should be intercepted, but when the quota is set, the prefabricated pile head is calculated according to the number, not by volume, but the part that is cut off should be calculated according to the volume, and the steel bars in the prefabricated piles should also be truncated according to the number of reinforcements.

There are many methods of pipe pile sinking, and the methods that have been constructed in China are: hammering method, static pressure method, vibration method, water injection method, pre-drilling method and middle excavation method, etc., and the static pressure method is used a lot.

Due to the violent vibration and loud noise of diesel hammer piling, in order to meet the needs of urban construction, in recent years, various parts of China have developed the process of pressurizing prestressed pipe piles with large-tonnage static pile drivers, and the static pile drivers can be divided into top pressure type and holding pressure type, and the pressure holding type is the clamping plate of the pile driver clamping the pile body, relying on the friction of the holding plate.

The principle of greater than the resistance to enter the soil works, and the static pile driver has a large pile pressing force of 5000-6000kn, and the diameter of the prestressed pipe pile can be pressed to the bearing layer required by the design.

Thus greatly promoting the application and development of prestressed pipe piles.

The depth of pile feeding without basement is the design pile top to the outdoor floor height plus 500. Your basement is relatively deep, and it should be excavated first and then piled, so the pile depth is designed to be the top of the pile to the stop surface (the bottom elevation of the raft cushion) plus 500.

Pile cutting head, prefabricated piles are generally calculated by the number, for example, the AB type high-strength prestressed pipe pile you use, the fixed length is 12 meters, and the piling record is 20 meters, then you have to count a pile cutting head, if the piling record is 24 meters, it is not considered the pile cutting head.

The elevation of the top of the pile is the elevation of the bottom of the cap.

The effective pile length is the elevation of the top of the pile minus the elevation of the bottom of the pile, and the settlement of the pile length is also calculated if it is a list valuation method, but the actual pile length should be considered when bidding. The original ground elevation to the elevation of the pile bottom, which is the settlement pile length.

It should be the elevation of the top of the pile. Look at the elevation of the Yellow Sea in the general plan, look at the plan of the pile foundation of the single building, look at the sample drawing of the pile foundation, and look at the foundation cap drawing, and you will know how to calculate the elevation of the pile top if you understand it.

The elevation of the top of the pile is known on the drawings.

What is the elevation of the Yellow Sea. Such as: the elevation of the Yellow Sea at the top of the pile.

As for the elevation of the pile bottom, it is indicated by the drawings or the drawings indicate that the pile length is several meters. After determining the elevation of the Yellow Sea, how much is the depth of foundation embedding, the top of the pile is 5 cm higher than the cushion, that is, the elevation of the pile top, and the length of the pile is the elevation of the bottom of the pile. Just take a closer look at the drawings and pile diagrams, and it's likely that your problem is already above.

Is there a record of pile testing? The design, construction, and supervision have all been signed and recorded very clearly.

The elevation of the pile top is lower than the design requirements, which can be divided into three situations: one is less than 2 times the pile diameter, and the pile is welded with other piles with intact pile heads; The second is within 2 times the pile diameter, the earthwork can be excavated around the pile, and the reinforcement cage under the secondary vertical mold is connected to the design elevation, and the third is that the cushion cap can be lowered if it is not much lower than the design elevation.

"How much is the pipe pile below the cap elevation allowed to be welded? Are you taking the pile? Generally not used.

How to deal with the elevation below the bearing cap, there is no clarity in the specification, so if it is generally not more than 10-20cm, it can be directly done "pot bottom" treatment, that is, the foundation cushion is made concave at the pile head position. If it is much lower, it will be reported to the design unit for processing, and the treatment method of deepening the foundation after deep excavation is generally adopted.

JGJ94-2008 "Technical Code for Building Pile Foundation" stipulates that the pile top should be embedded in the bottom of the cushion cap 50 100mm, (large pile 100 small pile 50). This is in every worker.

The description of the process or the pile will be clear on the sample.

When there is not much shortage, it can be solved by thickening the cushion cap, such as the inscription is 10cm---20cm lower, and the designer should be asked to deal with it on site.

How to do the pile top and bottom 280mm on the cushion cap.

The design pile length is the length from the top of the pile to the bottom of the pile according to the drawings, and this length is still in the design, or in theory, and has not been verified in practice, which is the design pile length.

The effective pile length is the length from the bottom of the pile to the top of the pile when the pile pressure force designed by the drawings is reached, such as the design of 20 meters, the actual 18 meters will meet the requirements, then the design pile length of 20 meters, the effective pile length of 18 meters, no matter how you match the pile, as long as it exceeds 18 meters, then the effective pile length is only counted to 18 meters.

The pile length refers to the distance from the natural level to the elevation of the pile top. It is to send the pile down from the natural level, generally the hammer machine is not more than 6 meters, and the static press is not more than 8 meters.

When making materials in construction, it is calculated according to the elevation of the top of the casing to the elevation of the bottom of the pile. However, when the contract is calculated, it is calculated according to the elevation of the ground surface to the elevation of the pile bottom given by the measurement.

How is the drilling depth of bored piles calculated? Is it a natural ground elevation or a casing mouth elevation? The drilling depth is the actual depth to be drilled.

Tell the worker and write it on the sign. The elevation of the casing - the elevation of the bottom of the pile + the margin of about 10cm. Why not natural ground.

Natural Ground** can be made to natural ground. The design of the pile depth, the position is fixed. It is not possible to control the drilling depth with natural ground.

So use the casing elevation.

The depth of the pile in the lower chamber is 500 from the design pile top to the outdoor floor height. Your basement is relatively deep, and it should be excavated first and then piled, so the pile depth is designed to be the top of the pile to the stop surface (the bottom elevation of the raft cushion) plus 500.

Pile cutting head, prefabricated piles are generally calculated by the number, such as the AB type high-strength prestressed pipe pile, the fixed length is 12 meters, and the piling record is 20 meters, then it is a pile cutting head, such as Peisheng Mengguo piling record Xiaohan is 24 meters, then it is not considered a pile cutting head.

For example, the pile is 12 meters, and the piling record is 20 meters, two piles should be used, 12 * 2-20 = 4, then 4 meters should be intercepted, but when the quota is set, the prefabricated pile head is calculated according to the number, not by volume, but the part that is cut off should be calculated according to the volume, and the steel bars in the prefabricated piles should also be truncated according to the number of reinforcements.

There are many methods of pipe pile sinking, and the methods that have been constructed in China are: hammering method, static pressure method, vibration method, water injection method, pre-drilling method and middle excavation method with bridge, etc., and the static pressure method is used a lot.

Due to the violent vibration and loud noise of diesel hammer piling, in order to meet the needs of urban construction, in recent years, various parts of our country have developed the process of pressing the prestressed pipe pile of the static pile driver of large tonnage, the static pile driver can be divided into the top pressure type and the pressure holding type, the pressure holding type is the clamping plate of the pile driver, relying on the principle that the friction force of the holding plate is greater than the resistance to the soil, the static pile driver has a large pile pressing force of 5000-6000kn, and the diameter of the prestressed pipe pile can be pressed to the bearing layer required by the design, Thus greatly promoting the application and development of prestressed pipe piles.

The formula for calculating the elevation of the pile bottom: v = cross-sectional area of the outer diameter of the pipe (design pile length + early length of irrigation and dust cleaning). The elevation of the top of the pile is the elevation of the top of the pile after the pile head is broken, and the part of the pile above this elevation belongs to the super brother high irrigation part (usually the loose answer layer).

How to deal with the elevation of the top of the prefabricated pipe pile lower than the design elevation of the cushion cap? What are the specification requirements? What are the on-site routines?

Dear, hello, I am happy to serve you, the answer is as follows how to deal with the elevation below Chengchun Li Tai, there is no clarity in the specification, so generally low is not more than 10-20cm, you can directly do the "pot bottom" treatment, that is, the foundation cushion is made concave at the pile head position. If it is much lower, it will be reported to the design unit for processing, and the method of deepening the foundation after deep excavation is generally used to make a late judgment. 1. Lengthen the anchor reinforcement by 500mm, support the formwork on the top of the pile, and pour 500mm concrete, so that the design elevation is reached.

Second, the cushion cap is heightened by 500mm, and the thickness of the cushion cap remains unchanged, and the wall on the cushion cap is heightened by 500mm