Novel BNT carrier pile and construction equipment construction method thereof

Abstract

The invention relates to the field of civil engineering, in particular to a novel BNT carrier pile and a construction equipment construction method of the novel BNT carrier pile. A pile hammer, a diesel hammer or a vibration hammer is used for replacing a shaking or rotary device as power, and a dowel bar and a replacement standard pile hammer are strongly combined with the BNT technology to achieve construction of the carrier pile. The high-quality potential of high bearing capacity of the carrier pile and the advantages of high pile forming quality and high applicability of the BNT technology are fully explored; some problems existing in the original carrier pile forming concept and construction are solved; through diversification of construction forms and equipment and by taking the three-strike penetration requirement as a criterion, the design and the construction are enabled to be based on the evidence; and complexity is replaced by simplicity, the process is simplified, and finally the BNT carrier pile with high bearing capacity, good effect, high speed, low cost and wider application range is realized to meet the increasingly high different requirements of engineering construction on pile foundations.

Description

technical field [0001] The invention relates to the field of civil engineering, in particular to a novel BNT carrier pile and a construction method for construction equipment thereof. Background technique [0002] When the bearing capacity of the natural foundation cannot meet the requirements, it is necessary to carry out foundation treatment or use a pile foundation, and how to improve the bearing capacity of a single pile when using a pile foundation has become a common concern. Carrier piles are invented on the basis of rammed and expanded piles. However, the rammed pile is restricted by its concept and technology. The area of ​​the expanded head at the pile end and the area affected by the soil mass at the pile end are small, so the increase in bearing capacity is limited. The carrier pile is the product of the combination of the "dynamic ram replacement" technology and the ram expansion pile construction in the foundation treatment; it is a denser, higher bearing capa...

AI Technical Summary

Problems solved by technology

[0011] (1) When encountering a high groundwater level or pressurized water, the standard column hammer cannot be constructed due to water and mud entering the pipe; Under the double action of negative pressure and viscous force, it will also make it very difficult to pull up the standard column hammer, especially in saturated sandy soil, if it is forced to pull up, it will easily cause water ingress or sand gushing in the pipe, making it difficult to continue the construction; What is more serious is the influence of factors such as the gap between the true diameter of the standard column hammer and the inner diameter of the outer pipe. When the standard column hammer freely falls to tamp the filling material, the air resistance, water resistance, mud resistance, etc. generated will directly lead to the actual tamping. The force effect is distorted and not easy to be found, resulting in discrete pile bearing capacity and low reliability of construction quality

Therefore, the original carrier pile can only be constructed under dry conditions without groundwater;

[0012] (2) The potential of some soil layers has not been fully utilized: the pile foundation generally chooses a higher bearing capacity, thicker and continuous soil layer as the bearing layer, but for those without a better natural bearing layer or better natural bearing When the depth of the layer is deep and it is not easy to use, choosing a soil layer with a relatively good bearing capacity can also achieve a higher bearing capacity after reinforcement treatment is a major potential advantage of the carrier pile, which is ignored.

It is also one of the reasons for the limited applicability;

[0013] (3) The optional range of pile diameter and pile length is small, which is also the main cause of limited applicability: the diameter of the standard column hammer determines the diameter range of the pile; and the effective height of the pile frame limits the maximum length of the pile

Due to the constraints of technology and equipment, the general carrier pile can only be used for the construction of short piles with small diameters;

[0014] (4) Using standard column hammers to carry out carrier pile construction has low tamping frequency and low construction efficiency, and the work efficiency is even lower when the ground conditions are affected. The existing technology uses double hammers, pile hammers or vibratory hammers for construction to improve construction efficiency. , but the upper and lower arrangement of the double hammer occupies a large part of the effective height of the pile frame, so that the actual pile length is limited, and it can only be adapted to the construction of small pile diameters and short piles; due to the requirement that "the length of the inner pipe is greater than the length of the outer pipe", It is difficult to implement waterproof and silt prevention measures under high water level conditions, and the quality of piles is not easy to control; during the construction of double hammer operations, the total mass and height of the hammers pose a challenge to the stability of the pile driver and increase the difficulty of operation. , requires higher technical personnel;

[0015] (5) In the prior art, the three-strike penetration is the key index to determine the bearing capacity of the carrier. When the pile hammer or vibratory hammer is used as the power to carry out the construction of the carrier pile, because the models of the pile hammer or vibratory hammer used are not uniform , so that the actual hammering force is not the same, but it is not easy to keep consistent with the three-strike penetration requirements, resulting in no basis for design and construction, and difficult to control the construction quality;

[0016] (6) As a special construction equipment, not only the investment is large but also the function is single, and the utilization rate of the equipment is limited, resulting in waste of investment;

[0017] (7) Low construction efficiency: hydraulic shaking or rotary methods are used to form holes, regardless of the speed of sinking and pulling pipes; the grabbing bucket takes a small amount of soil each time and the frequency is low; the pile driver is time-consuming and laborious to move in place;

[0018] (8) High cost and few optional pile diameter specifications: due to the investment in equipment and steel casings, general construction units lack economic strength, and it is difficult to purchase casings of various diameters and specifications, so the pile diameters are limited to a certain extent; Due to the limitations of equipment and equipment, it cannot be applied to the construction of small piles;

[0019] (9) Huge equipment: a large construction site is required for construction, and the distance from the boundary of the construction site to the center of the side pile is also required to be relatively large. It is difficult to survive today when the construction land is very expensive.

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