阅读说明：本技术 处理基桩顶部缩颈问题的护筒结构及施工方法 (Pile casing structure for treating necking problem at top of foundation pile and construction method ) 是由 穆保岗 杨彤薇 于 2019-09-10 设计创作，主要内容包括：本发明公开了一种处理基桩顶部缩颈问题的护筒结构及其施工方法,采用预制钢筋混凝土护筒结构现场进行装配的加固方法,护筒结构分为多层,每层由四片弧形环片组成加固圆环,弧形环片之间采用螺栓连接,护筒结构安装完成后通过预留注浆孔注浆使护筒结构与桩身连接成为一个整体。本发明具有装配难度低、施工速度快、加固效果显著等优点,本发明施工所需场地小,能够在竖向空间不足的条件下完成装配,可同时对多基桩进行加固施工。(The invention discloses a pile casing structure for treating the problem of necking down at the top of a foundation pile and a construction method thereof. The invention has the advantages of low assembly difficulty, high construction speed, obvious reinforcing effect and the like, requires a small construction field, can complete assembly under the condition of insufficient vertical space, and can simultaneously carry out reinforcing construction on multiple base piles.)

1. The utility model provides a handle a section of thick bamboo structure that protects of foundation pile top necking down problem, its characterized in that includes a plurality of arc reinforcement pieces, can dismantle the connection between the arc reinforcement piece, be provided with the slip casting hole on the arc reinforcement piece, be provided with elastic seal structure in the arc reinforcement piece, elastic seal structure is provided with the pre-grouting hole that runs through.

2. A casing structure for handling a problem of necking in the top of a foundation pile according to claim 1, wherein the arc-shaped reinforcing sheets are provided with a transverse connecting member and a longitudinal connecting member.

3. A casing structure for treating a necking problem at the top of a foundation pile according to claim 2, wherein the arc-shaped reinforcing strips are connected with each other by a transverse connecting member and a bolt to form reinforcing rings, and the reinforcing rings are connected with each other by a longitudinal connecting member and a bolt.

4. A casing structure for treating necking problem at top of foundation pile according to claim 1, wherein an adaptive grout stop plug is arranged in the grouting hole.

5. A pile casing structure for solving the problem of necking at the top of a foundation pile according to claim 1, wherein a reinforcing mesh is provided in the arc-shaped reinforcing sheet to improve the overall strength of the pile casing structure.

6. A construction method of a casing structure for handling a problem of necking in the top of a foundation pile according to claim 1, comprising the steps of:

(S1) determining the number and the positions of foundation piles to be reinforced, excavating and removing soil around the piles, honeycomb and hollow concrete, leveling the soil around the piles, and determining the size, the installation position and the number of the prefabricated reinforced concrete pile casing structures according to the size and the range of the foundation piles to be reinforced;

(S2) sequentially hanging the prefabricated reinforced concrete arc-shaped reinforcing ring pieces (1) at the bottom layer, aligning the transverse connecting members (3) of two adjacent arc-shaped reinforcing ring pieces (1), and installing bolts (12);

(S3) sequentially hanging the four next layers of arc-shaped reinforcing ring sheets (1) to align the longitudinal connecting members (4) of the upper layer and the lower layer, and installing bolts (12) until the top layer reinforcing ring is installed;

(S4) injecting cement slurry into the elastic sealing structure (9) on the inner side of each arc-shaped reinforcing ring piece (1) on the top and bottom layers through the pre-grouting hole (10), stopping grouting after the top and bottom ends of the pile casing structure are tightly attached to the pile body, and installing a grout stopping plug (5) to form a temporary sealing structure;

(S5) grouting layer by layer through the grouting holes (8) according to the sequence from bottom to top, stopping grouting when the gap between the pile casing structure and the foundation pile is completely filled with cement slurry, installing a grout stop plug (5), and backfilling the excavated soil body to finish construction.

Technical Field

The invention relates to a building foundation pile reinforcing structure and a construction method, in particular to a pile casing structure for solving the problem of necking at the top of a foundation pile and a construction method.

Background

Pile foundations play a very important role in civil engineering construction, where the quality of the foundation piles affects the safety of the entire structure. In actual work progress, because geological survey does not put in place, the design is unreasonable, reasons such as improper construction for quality problems such as pile shaft necking down frequently take place, if can not solve the quality problem of pile shaft in time, will bring very big potential safety hazard for superstructure. Therefore, the research work for processing the quality problem of the foundation pile has theoretical value and very wide engineering application prospect, and the research result can bring good economic and social benefits.

At present, the treatment methods aiming at quality problems of pile body necking and the like mainly comprise a pile end grouting method, a pile filling method and a foundation rigidity increasing method. If the part of the foundation pile with quality problems appears in the depth range of 2-5m from the ground surface at the top of the foundation pile, the method for treating the foundation pile often has the problems of long construction period, large engineering quantity, difficult site conditions, unobvious reinforcing effect and the like.

Disclosure of Invention

The purpose of the invention is as follows: the invention aims to provide a pile casing structure for treating the problem of necking at the top of a foundation pile and a construction method, and solves the problems of poor reinforcing effect, complex construction and long period.

The technical scheme is as follows: the pile casing structure for treating the necking problem at the top of the foundation pile comprises a plurality of arc-shaped reinforcing plates, wherein the arc-shaped reinforcing plates are detachably connected, grouting holes are formed in the arc-shaped reinforcing plates, and transverse connecting members and longitudinal connecting members are arranged on the arc-shaped reinforcing plates.

The arc-shaped reinforcing plates are connected through transverse connecting members and bolts to form reinforcing rings, and the reinforcing rings are connected through longitudinal connecting members and bolts.

And a matched grout stopping plug is arranged in the grouting hole.

In order to improve the shearing strength of the pile casing structure and increase the integrity of the pile casing structure, a reinforcing mesh is arranged in the arc reinforcing sheet.

The construction method of the pile casing structure for treating the necking problem at the top of the foundation pile comprises the following steps of:

(S1) determining the number and the positions of foundation piles to be reinforced, excavating and removing soil around the piles, honeycomb and hollow concrete, leveling the soil around the piles, and determining the size, the installation position and the number of the prefabricated reinforced concrete pile casing structures according to the size and the range of the foundation piles to be reinforced;

(S2) sequentially hanging the prefabricated reinforced concrete arc-shaped reinforcing ring pieces on the bottom layer, aligning the transverse connecting members of two adjacent arc-shaped reinforcing ring pieces, and installing bolts;

(S3) sequentially hanging the four arc-shaped reinforcing ring pieces of the next layer, aligning the longitudinal connecting members of the upper layer and the lower layer, and installing bolts until the top layer reinforcing ring is installed;

(S4) injecting cement slurry into the elastic sealing structure on the inner side of each arc-shaped reinforcing ring piece on the top and bottom layers through the pre-grouting hole, stopping grouting after the top and bottom ends of the pile casing structure are tightly attached to the pile body, and installing a grout stopping plug to form a temporary sealing structure;

(S5) grouting layer by layer through the grouting holes in the sequence from bottom to top, stopping grouting when the gap between the pile casing structure and the foundation pile is completely filled with cement slurry, installing a grout stop plug, and backfilling the excavated soil body to complete construction.

Has the advantages that: the pile casing structure consists of a plurality of small-volume ring sheets, can be produced in batches with multiple specifications, is convenient to transport and simple and quick to install, does not need large-scale mechanical equipment and complex construction, and is suitable for reinforcing and repairing the top of a foundation pile; the pile casing structure does not affect the foundation and the upper structure during construction, can be installed and reinforced by using a limited vertical construction space, can also be used for reinforcing multiple foundation piles simultaneously, and shortens the construction period; the construction method can lead the pile casing structure and the pile body to be tightly combined together through cement paste, and can effectively solve the quality problems of necking, honeycombing, insufficient bearing capacity and the like of the foundation pile.

Drawings

Fig. 1 is a schematic cross-sectional view of a casing structure according to the present invention;

FIG. 2 is a schematic perspective view of a top layer arc-shaped reinforcing ring plate in the casing structure according to the present invention;

FIG. 3 is a schematic perspective view of an intermediate layer arc-shaped reinforcing ring plate in the casing structure according to the present invention;

FIG. 4 is a schematic perspective view of a bottom arc-shaped reinforcing ring plate in the casing structure according to the present invention;

FIG. 5 is a schematic perspective view of a reinforcing ring in the casing structure according to the present invention;

fig. 6 is a schematic diagram of reinforcement of an arc-shaped reinforcing ring plate in the pile casing structure according to the present invention.

Detailed Description

The invention is further described below with reference to the accompanying drawings.

As shown in fig. 1-5, the pile casing structure for solving the problem of necking down at the top of a foundation pile comprises an arc-shaped reinforcing ring sheet 1, a connecting member and an elastic sealing structure 9, wherein the arc-shaped reinforcing ring sheet 1 is a prefabricated reinforced concrete arc-shaped member and is in the shape of a quarter of an arc, the concrete strength grade is C30, the height of the arc-shaped reinforcing ring sheet 1 is 800mm, the thickness of the arc-shaped reinforcing ring sheet is 150mm, two rows of reinforcing meshes 13 are arranged in the arc-shaped reinforcing ring sheet 1, the connecting member 2 comprises a transverse connecting member 3 and a longitudinal connecting member 4 which are both arranged at the outer edge of the arc-shaped reinforcing sheet, and a grouting hole 8 and a grout stop plug 5 are arranged at the center of the arc-shaped reinforcing ring sheet 1 and are; the arc-shaped reinforcing ring pieces 1 positioned at the two ends of the top and the bottom are also provided with an elastic sealing structure 9 and a pre-grouting hole 10, the elastic sealing structure 9 is an arc-shaped hollow rubber bag, one side of the elastic sealing structure is tightly attached to the inner wall of the arc-shaped reinforcing ring piece, a round opening with the same size and shape is arranged at the position, corresponding to the pre-grouting hole 10, of the connecting side, after the installation of the pile casing structure is completed, cement slurry is injected into the rubber bag through the pre-grouting hole 10, the pile casing structure is tightly connected with the pile body to form temporary sealing, the diameters of the grouting hole 8 and the pre-grouting hole 10 are both 40-60mm, and the cement slurry is quick; the 4 arc-shaped reinforcing ring pieces 1 are connected pairwise through the transverse connecting members 3 to form a complete reinforcing ring, the upper reinforcing ring and the lower reinforcing ring are connected through the longitudinal connecting members 4 to form a reinforcing pile casing structure, the pile casing structure can be prefabricated into different specifications, the inner diameter of the selected pile casing structure needs to be slightly larger than the diameter of the pile body 9, and the number and the specification of the reinforcing rings needed by the selected pile casing structure are determined according to the size of a region with necking of the foundation pile; each connecting member comprises a connecting seat 6, bolt holes 7 and bolts 12, the connecting seat 6 is 200mm long, 150mm wide and 50mm thick, the diameters of the bolt holes 7 are 26mm, the number of the bolt holes is 4, and the bolts 12 are M24 type bolts; two rows of reinforcing mesh 13 are arranged in the arc-shaped reinforcing ring piece 1, the reinforcing mesh 13 adopts reinforcing steel bars with the diameter of 12.6mm, the interval is 100mm, the reinforcing mesh at the two sides and the upper edge and the lower edge is encrypted, the interval is 50mm, and the part connected with the connecting member 2 is additionally provided with reinforcing steel bars which extend into the connecting member 2.

When the method is used, the number and the positions of foundation piles to be reinforced are determined, soil around the piles, honeycomb and hollow concrete are excavated and removed, the soil around the piles is leveled, and the size, the installation position and the number of the prefabricated reinforced concrete pile casing structures are determined according to the size and the range of the foundation piles to be reinforced; sequentially hoisting four prefabricated reinforced concrete arc-shaped reinforcing ring sheets 1 at the bottom layer, aligning the horizontal connecting members 3 of two adjacent arc-shaped reinforcing ring sheets 1, and installing bolts 12; sequentially hanging the four arc-shaped reinforcing ring pieces 1 of the next layer to align the longitudinal connecting members 4 of the upper layer and the lower layer, and installing bolts 12; repeating the step 3 until the top layer reinforcing circular ring is installed; injecting cement slurry into the elastic sealing structure 9 on the inner side of each arc-shaped reinforcing ring piece 1 on the top and bottom layers through the pre-grouting hole 10, stopping grouting after the top and bottom ends of the pile casing structure are tightly attached to the pile body, and installing a grout stop plug 5 to form a temporary sealing structure; grouting layer by layer through the grouting holes 8 in the sequence from bottom to top, stopping grouting when the gap between the pile casing structure and the foundation pile is completely filled with cement slurry, and installing a grout stop plug 5; backfilling the excavated soil body.