阅读说明：本技术 深基坑钻孔围护结构非咬合型止水桩综合施工方法 (Comprehensive construction method for non-occluded water stop pile of deep foundation pit drilling support structure ) 是由 桂林 于 2020-05-29 设计创作，主要内容包括：本发明公开了深基坑钻孔围护结构非咬合型止水桩综合施工方法,涉及深基坑钻孔领域,为达到上述目的,本发明的技术方案包括如下步骤：1)围护结构第1批跳桩施工；2)围护结构第2批止水桩钻孔；3)基坑开挖；4)桩头拆离；5)深基坑开挖。减少了咬合桩施工需采用错管机或旋挖钻机等大型设备使用或采用高压旋喷外侧止水施工方法,机械设备费用以及人工辅助等大大降低,成本降低。(The invention discloses a comprehensive construction method of a non-occluded water stop pile of a deep foundation pit drilling support structure, which relates to the field of deep foundation pit drilling and aims to achieve the purpose, and the technical scheme of the invention comprises the following steps: 1) constructing the 1 st batch of jumping piles of the enclosure structure; 2) drilling a water stop pile in the 2 nd batch of the enclosure structure; 3) excavating a foundation pit; 4) detaching the pile head; 5) and (5) excavating the deep foundation pit. The construction of the secant pile needs to adopt large equipment such as a pipe staggering machine or a rotary drilling rig or adopt a high-pressure rotary spraying outer side water stopping construction method, the cost of mechanical equipment, manual assistance and the like are greatly reduced, and the cost is reduced.)

1. The comprehensive construction method of the deep foundation pit drilling enclosure structure non-occluded water stop pile is characterized by comprising the following steps of:

1) constructing the 1 st batch of jumping piles of the enclosure structure;

2) drilling a water stop pile in the 2 nd batch of the enclosure structure;

3) excavating a foundation pit;

4) detaching the pile head;

5) and (5) excavating the deep foundation pit.

2. The comprehensive construction method of the deep foundation pit drilling envelope non-occluded water stop pile according to claim 1, characterized in that: the construction of the 1 st batch of jumping piles of the enclosure structure comprises the following steps:

A. measuring and positioning and arranging pile holes: the cast-in-place bored piles are arranged around the foundation pit in a circle according to the enclosure structure, the cast-in-place bored piles are firstly constructed by jumping at least 1 pile at intervals, and then cast-in-place piles in the interval area are constructed;

B. investigating geological conditions and selecting a drilling machine;

C. embedding the steel casing;

D. drilling by a drilling machine;

E. checking and cleaning the formed holes;

F. processing in a reinforcement cage field;

G. processing the pile head in a reinforcing cage site with a broken protective sleeve;

H. and (5) secondary hole cleaning and pouring.

3. The comprehensive construction method of the deep foundation pit drilling envelope non-occluded water stop pile according to claim 2, characterized in that: the drilling of the 2 nd batch of water stop piles of the building envelope comprises the following steps: the cast-in-place bored piles are arranged around the foundation pit in a circle according to the building enclosure, the cast-in-place bored piles are firstly constructed by jumping at least 1 pile at intervals, and then cast-in-place bored piles in the interval area are constructed.

4. The comprehensive construction method of the deep foundation pit drilling envelope non-occluded water stop pile according to claim 1, characterized in that: excavation of a foundation pit: firstly, constructing a top crown beam, and gradually excavating under working conditions after the strength of the top crown beam meets the design requirement. And (5) stopping excavating when the excavation is 0.5m below each supporting position, hoisting the supporting system, applying a jacking force, and continuing excavating downwards.

5. The comprehensive construction method of the deep foundation pit drilling envelope non-occluded water stop pile according to claim 1, characterized in that: pile head detaching: the pile head is detached, firstly, lines are drawn at the cutting position of the pile head and cut by adopting a circular cutting technology, 1-2 cm above the cutting line, hole sites are uniformly and symmetrically arranged on each pile along the periphery of the pile head, a pneumatic pick is used for punching, and the punching depth is the diameter of the pile so as to insert a steel chisel. The driving is carried out symmetrically and horizontally as much as possible so as to ensure that the fracture surface is kept at the same horizontal plane. After drilling is completed, inserting wedge-shaped steel rods, drilling and jacking the broken pile heads, enabling the steel rods to be horizontal or slightly upward, and then knocking the steel rods repeatedly by adopting a sledge hammer to knock back and forth so as to break the concrete at the annular broken pile holes. Each steel chisel is provided with two clamping pieces, and the steel chisel can be taken out conveniently after the pile head is broken. If the wedge-shaped steel rod does not support the concrete, the hoisting rope is lifted by the pre-buried U-shaped lifting hook and the crane. .

6. The comprehensive construction method of the deep foundation pit drilling envelope non-occluded water stop pile according to claim 1, characterized in that: and (3) excavating the deep foundation pit, namely excavating the foundation pit to a position 100cm below the first layer of waist beam by using a long-arm excavator, constructing the first layer of waist beam and the inclined support, excavating the foundation pit to a position 100cm below the second layer of waist beam by using the long-arm excavator. And constructing a waist beam and an inclined support at the position of the second inner support, excavating a foundation pit by using a long-arm excavator until the height of the bottom of the bearing platform is 50cm, arranging a water collecting pit at the inner side of the foundation pit, pumping water and constructing a broken stone cushion layer. And (5) checking and accepting the foundation pit, and entering the next procedure after the foundation pit is qualified.

Technical Field

The invention relates to a comprehensive construction method of a non-occluded water stop pile of a deep foundation pit drilling support structure, and mainly relates to the field of deep foundation pit drilling.

Background

With the continuous and rapid advance of the construction of basic facilities in China, the construction technology of basic engineering is changed day by day, and the construction of deep foundation pits is more, including underground continuous walls, steel sheet pile supports, cast-in-situ bored piles supports, SMW construction method piles, steel pipe piles supports, anchor cable piles supports and the like, and different support modes are selected according to different geological conditions and surrounding environments. Deep foundation pit construction is carried out in geology such as a sandy gravel stratum or a compact sand layer, steel sheet pile supporting is difficult to insert and beat, and the construction cost of the underground continuous wall is high.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a comprehensive construction method of a non-occluded water stop pile of a deep foundation pit drilling enclosure structure, which reduces the need of using large-scale equipment such as a pipe staggering machine or a rotary drilling rig or using a high-pressure rotary spraying outer side water stop construction method in occluded pile construction, greatly reduces the cost of mechanical equipment, manual assistance and the like, and reduces the cost.

In order to achieve the purpose, the technical scheme of the invention is as follows: the method comprises the following steps: 1) constructing the 1 st batch of jumping piles of the enclosure structure; 2) drilling a water stop pile in the 2 nd batch of the enclosure structure; 3) excavating a foundation pit; 4) detaching the pile head; 5) and (5) excavating the deep foundation pit.

Preferably, the 1 st batch of pile skipping construction of the building enclosure comprises the following steps: A. measuring and positioning and arranging pile holes: the cast-in-place bored piles are arranged around the foundation pit in a circle according to the enclosure structure, the cast-in-place bored piles are firstly constructed by jumping at least 1 pile at intervals, and then cast-in-place piles in the interval area are constructed; B. investigating geological conditions and selecting a drilling machine; C. embedding the steel casing; D. drilling by a drilling machine; E. checking and cleaning the formed holes; F. processing in a reinforcement cage field; G. processing the pile head in a reinforcing cage site with a broken protective sleeve; H. and (5) secondary hole cleaning and pouring.

Preferably, the 2 nd batch of water stop pile drilling of the building envelope comprises the following steps: the cast-in-place bored piles are arranged around the foundation pit in a circle according to the building enclosure, the cast-in-place bored piles are firstly constructed by jumping at least 1 pile at intervals, and then cast-in-place bored piles in the interval area are constructed.

Preferably, excavation of the foundation pit: firstly, constructing a top crown beam, and gradually excavating under working conditions after the strength of the top crown beam meets the design requirement. And (5) stopping excavating when the excavation is 0.5m below each supporting position, hoisting the supporting system, applying a jacking force, and continuing excavating downwards.

Preferably, the pile head is detached: the pile head is detached, firstly, lines are drawn at the cutting position of the pile head and cut by adopting a circular cutting technology, 1-2 cm above the cutting line, hole sites are uniformly and symmetrically arranged on each pile along the periphery of the pile head, a pneumatic pick is used for punching, and the punching depth is the diameter of the pile so as to insert a steel chisel. The driving is carried out symmetrically and horizontally as much as possible so as to ensure that the fracture surface is kept at the same horizontal plane. After drilling is completed, inserting wedge-shaped steel rods, drilling and jacking the broken pile heads, enabling the steel rods to be horizontal or slightly upward, and then knocking the steel rods repeatedly by adopting a sledge hammer to knock back and forth so as to break the concrete at the annular broken pile holes. Each steel chisel is provided with two clamping pieces, and the steel chisel can be taken out conveniently after the pile head is broken. If the wedge-shaped steel rod does not support the concrete, the hoisting rope is lifted by the pre-buried U-shaped lifting hook and the crane. .

Preferably, the deep foundation pit is excavated, namely, a long-arm excavator is used for excavating the foundation pit to a position 100cm below the first layer of waist beam, the first layer of waist beam and the inclined support are constructed, the long-arm excavator is used for excavating the foundation pit to a position 100cm below the second layer of waist beam. And constructing a waist beam and an inclined support at the position of the second inner support, excavating a foundation pit by using a long-arm excavator until the height of the bottom of the bearing platform is 50cm, arranging a water collecting pit at the inner side of the foundation pit, pumping water and constructing a broken stone cushion layer. And (5) checking and accepting the foundation pit, and entering the next procedure after the foundation pit is qualified.

The technical principle and the beneficial effects of the invention are as follows:

the method has the advantages of avoiding the need of a pipe staggering machine or a large rotary drilling rig for the secant pile construction, having low work efficiency and the like, having remarkable treatment effect, improving the construction work efficiency, reducing the labor intensity of workers, providing reference for solving similar engineering construction, having good popularization and application values, reducing the need of using large equipment such as the pipe staggering machine or the rotary drilling rig for the secant pile construction or adopting a high-pressure rotary spraying outer side water stopping construction method, greatly reducing the cost of mechanical equipment, manual assistance and the like, and reducing the cost.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments will be briefly introduced below, it is obvious that the drawings in the following description are only two of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic plan view of a batch-wise bored pile position arrangement according to an embodiment of the present invention;

FIG. 2 is a schematic side view of a pile cleaned by high pressure injection water before construction of pile batch 2 according to an embodiment of the present invention;

fig. 3 is a schematic view of the pile head according to the embodiment of the present invention.

Detailed Description

The technical solutions in the present invention will be described clearly and completely with reference to the accompanying drawings, and it is to be understood that the described embodiments are merely preferred embodiments of the present invention, rather than all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.