Foundation pile stabilizing construction method for super-soft foundation

Abstract

The invention discloses a foundation pile stabilizing construction method for an ultra-soft foundation, which relates to the technical field of foundation treatment and comprises the following steps: constructing a continuous pile stabilizing plate in an ultra-soft soil foundation in advance: constructing the continuous pile stabilizing plate in a building foundation; and piling is conducted in the foundation, specifically, the pile foundations are driven in the foundation, and the tops of the pile foundations are fixedly embedded in the continuous pile stabilizing plate. According to the construction method, the continuous pile stabilizing plate is constructed in advance, so that the tops of all the pile foundations are fixedly embedded and then cannot move, all the pile foundations and the continuous pile stabilizing plate are connected into a whole, and an imaginary solid deep foundation defined by the pile foundations and the continuous pile stabilizing plate system is formed, so that the stability of the pile foundations and the foundation is improved; the pile foundation center is prevented from systematically deviating from the axis, and the foundation bearing capacity is greatly improved. In addition, the continuous pile stabilizing plate can greatly improve the counterforce of the foundation, the bearing capacity of the original foundation is fully exerted, and then the safety and stability of buildings on the foundation are improved.

Description

Technical Field

[0001] The invention relates to the technical field of foundation treatment, and in particular to a method for constructing ultra-soft foundation stabilizing piles. Background Art

[0002] There are a lot of ultra-soft soil geological phenomena in soft soil foundation areas (Guangdong coastal areas, Shanghai, Jiangsu, Zhejiang, Shandong, etc.). Building houses on ultra-soft soil (high water content, high porosity, large deformation) requires pile foundation or pile-soil composite foundation to be treated, so piles are a necessary structural form of the foundation. However, since the original foundation is extremely soft and has almost no bearing capacity, heavy construction machinery cannot operate on the foundation. Therefore, the following technical measures are often required: (1) In order to prevent large pile driving equipment from sinking into the foundation and being unable to move, measures are taken to backfill and compact construction waste along the perimeter of the site in advance, and then super-thick steel plates are laid on the compacted construction waste. Then, the pile driving machinery is placed on the steel plates for walking construction. This process not only causes a huge waste of construction costs, but also seriously delays the construction period, especially the high labor intensity and poor working environment of the workers; (2) After the pile foundation construction is completed, the previously laid construction waste must be excavated and transported out. In most cases, the excavated waste residue has a high water content and cannot be smoothly transported out due to environmental protection issues. It needs to be dried on site or stored on site, resulting in cost waste and extended construction period; (3) When the site is excavated, since the original foundation is super soft soil, the foundation has no bearing capacity and no shear resistance, resulting in the pile foundation constructed previously seriously tilted to one side, not only wasting a lot of pile foundation correction costs, but even many pile foundation projects are scrapped due to a large amount of tilt.

[0003] Based on this, a new solution is urgently needed to solve the above problems. Summary of the invention

[0004] The purpose of the present invention is to provide a method for stabilizing piles in ultra-soft foundation to solve the problems existing in the above-mentioned prior art. It can not only save a lot of construction costs and speed up the construction period, but also the pile foundation project can meet the design axis requirements and meet the stability and bearing capacity requirements of the foundation.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a method for constructing ultra-soft foundation piles, comprising:

[0007] Establishing a continuous pile stabilization board: using a floating excavator to drive a powder spraying or shotcrete mixer to construct the continuous pile stabilization board under the raft or pile foundation cap specified in the design of the super-soft soil site, and the thickness of the continuous pile stabilization board is determined by the design;

[0008] Piling: According to the requirements of pile foundation design, construction machinery is placed on the pile stabilizing plate to drive piles into the foundation, and the top of each pile is embedded in the continuous pile stabilizing plate, so that the pile foundation and the continuous pile stabilizing plate are connected as a whole.

[0009] Preferably, a floating excavator is used to drive a powder spraying or shotcrete mixer to construct a continuous pile stabilization board on an ultra-soft soil foundation. Subsequently, after the continuous pile stabilization board solidifies, a pile foundation is immediately constructed using a pile driving machine. The top of the pile is embedded in the continuous pile stabilization board and is closely integrated with the continuous pile stabilization board.

[0010] Preferably, the continuous pile stabilization board is established by extending downward from the bottom elevation of the building foundation.

[0011] Preferably, the silt or loose soil on the upper part of the continuous pile stabilization plate is removed when the foundation trench is excavated.

[0012] Preferably, in the step of establishing the continuous pile stabilization board, the target stratum is reinforced by spraying curing agent slurry or powder into the target stratum while the stirring head of the construction machinery is rotated, and the curing agent slurry or powder is sprayed into the target stratum while stirring.

[0013] Preferably, the construction machinery mixing head is a double-head mixing head for up and down mixing, or a single-head mixing head for left and right rotation mixing; the construction machinery mixing head is one or more.

[0014] Preferably, the continuous pile stabilizing plate is a continuous plate body.

[0015] Preferably, the thickness of the continuous pile stabilization board is 2.5 to 3.5 m.

[0016] Compared with the prior art, the present invention has achieved the following technical effects:

[0017] The present invention connects the tops of all pile foundations into a whole by establishing a continuous pile stabilizing plate, thereby improving the stability of the top of the pile foundation and preventing the center of the top of the pile foundation from systematically deviating from the axis, causing engineering quality accidents. In addition, the continuous pile stabilizing plate can also increase the foundation reaction force, thereby improving the stability of the building on the foundation and enhancing the seismic stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A schematic diagram of a foundation structure after using the ultra-soft foundation stabilizing pile construction method provided by an embodiment of the present invention;

[0020] In the figure: 1- continuous pile stabilization board; 2- pile foundation; 3- foundation bearing layer; 4- bottom elevation of building foundation; 5- natural ground. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] The present invention provides a method for constructing ultra-soft foundation piles. Figure 1 As shown, including:

[0024] Establish continuous pile stabilization board 1: Use floating excavator to drive powder spraying or shotcrete mixer to construct continuous pile stabilization board 1 under the raft or pile foundation 2 cap specified in the design of super soft soil site. The thickness of continuous pile stabilization board 1 is determined by design; the thickness of continuous pile stabilization board 1 is generally 2.5 to 3.5m.

[0025] Piling: Piles are driven into the foundation according to the design requirements of the pile foundation 2, and the tops of the piles are embedded in the continuous pile stabilization plate 1, so that the pile foundation 2 and the continuous pile stabilization plate 1 are connected as a whole.

[0026] The present invention connects the tops of all pile foundations 2 into a whole by establishing a continuous pile stabilizing plate 1, thereby improving the stability of the pile foundation 2 and preventing the center of the pile foundation 2 from systematically deviating from the axis. In addition, the continuous pile stabilizing plate 1 can also increase the foundation reaction force, thereby improving the stability of the building on the foundation.

[0027] In some embodiments, a floating excavator is used to drive a powder spraying or shotcrete mixer to construct a continuous pile stabilization board 1 on an ultra-soft soil foundation. Subsequently, after the continuous pile stabilization board 1 solidifies, a pile foundation 2 is immediately constructed using a pile driving machine, and the top of the pile is embedded in the continuous pile stabilization board 1 and is closely integrated with the continuous pile stabilization board 1.

[0028] In some embodiments, the continuous pile stabilization board 1 is extended downward from the building foundation bottom elevation 4. That is, the top surface height of the continuous pile stabilization board 1 is the building foundation bottom elevation 4, and the raft or cap of the subsequent building is directly built on the continuous pile stabilization board 1.

[0029] In some embodiments, the silt or loose soil on the continuous pile stabilization plate 1 is removed when the foundation trench is excavated.

[0030] This embodiment is suitable for construction conditions where silt is difficult to remove. The use of this embodiment can improve construction efficiency. Specifically, since it is necessary to wait for a solidification period after the continuous pile stabilization board 1 is established to allow the continuous pile stabilization board 1 to solidify, silt can be excavated during this period, which avoids the construction window period and thus improves construction efficiency.

[0031] In some embodiments, in the step of establishing the continuous pile stabilization board 1, the target stratum is reinforced by spraying the curing agent slurry or powder into the target stratum while the stirring head of the construction machine rotates and stirs at the same time.

[0032] In some embodiments, the construction machinery mixing head is a double-head mixing head for up and down mixing, or a single-head mixing head for left and right rotation mixing; the construction machinery mixing head is one or more.

[0033] In some embodiments, the continuous pile stabilizing plate 1 is a continuous plate body.

[0034] In some embodiments, during the piling step, the bottom of the pile foundation 2 is driven into the foundation bearing layer 3 .

[0035] This embodiment connects the bottom of the pile foundation 2 into a whole, which can further stabilize the pile foundation 2 so that all the pile foundations 2 form an integral structure.

[0036] In some embodiments, when excavating the foundation pit in the above embodiments, if in some areas with high silt mobility such as river beaches, it is necessary to first enclose a foundation pit area and then excavate the silt therein to prevent the surrounding silt from flowing into the foundation pit.

[0037] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A method for stabilizing piles in ultra-soft foundation, characterized by: include: Establishing a continuous pile stabilization board: using a floating excavator to drive a powder spraying or shotcrete mixer to construct the continuous pile stabilization board at the raft or pile foundation cap elevation specified in the design of the super-soft soil site, and the thickness of the continuous pile stabilization board is determined by the design; Piling: Piles are driven into the foundation according to the pile foundation design requirements, and the tops of the piles are embedded in the continuous pile stabilization board, so that the pile foundation and the continuous pile stabilization board are connected as a whole.

2. The ultra-soft foundation stabilization pile construction method according to claim 1 is characterized by: A floating excavator is used to drive a powder spraying or shotcrete mixer to construct a continuous pile stabilization board on an ultra-soft soil foundation. Subsequently, after the continuous pile stabilization board solidifies, a pile foundation is immediately constructed using a pile driving machine. The top of the pile is embedded in the continuous pile stabilization board and is closely integrated with the continuous pile stabilization board.

3. The ultra-soft foundation stabilization pile construction method according to claim 1 is characterized by: The continuous pile stabilization plate is extended downward from the bottom elevation of the building foundation.

4. The ultra-soft foundation stabilization pile construction method according to claim 1 is characterized by: The silt or loose soil on the continuous pile stabilizing plate is removed when the foundation trench is excavated.

5. The ultra-soft foundation stabilization pile construction method according to claim 1 is characterized by: In the step of establishing the continuous pile stabilization board, the target stratum is reinforced by spraying curing agent slurry or powder into the target stratum while the construction machinery stirring head is rotating, and the target stratum is stirred while being injected.

6. The method for stabilizing piles in ultra-soft foundation according to claim 5 is characterized by: The construction machinery mixing head is a double-head mixing head for up and down mixing, or a single-head mixing head for left and right rotation mixing; the construction machinery mixing head is one or more.

7. The method for stabilizing piles in ultra-soft foundation according to claim 1 is characterized by: The continuous pile stabilizing plate is a continuous plate body.

8. The method for stabilizing piles in ultra-soft foundation according to claim 1 is characterized by: The thickness of the continuous pile stabilization board is 2.5 to 3.5 m.

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