CN216075211U

CN216075211U - Combined pile system for treating deep collapsible loess foundation

Info

Publication number: CN216075211U
Application number: CN202121218532.4U
Authority: CN
Inventors: 姚成龙; 严小宝; 柳丙军
Original assignee: China MCC17 Group Co Ltd
Current assignee: China MCC17 Group Co Ltd
Priority date: 2021-06-02
Filing date: 2021-06-02
Publication date: 2022-03-18
Anticipated expiration: 2031-06-02

Abstract

The utility model discloses a combined pile system for treating a deep collapsible loess foundation, and relates to the technical field of geotechnical engineering. This combination stake system to deep collapsible loess foundation is handled, including crowded close stake of lime soil, PTC tubular pile cap, 5% lime soil bed course and collapsible loess, 5% lime soil bed course is laid at collapsible loess foundation top surface, the bottom of 5% lime soil bed course is provided with multirow lime soil crowded close stake and PTC tubular pile in turn. The PTC tubular pile in the combined pile system for treating the deep collapsible loess foundation is implemented in a driving mode, the traditional single lime soil compaction pile arrangement mode is replaced at intervals, the transverse extrusion effect of the pile on soil among piles is fully exerted, the pile cap and the lime soil cushion layer are arranged through the pile top, the bearing capacity of the composite foundation is greatly improved, and a new treatment scheme is provided for the deep collapsible loess foundation of a special road section. The utility model not only reduces the engineering cost, but also ensures the treatment effect.

Description

Combined pile system for treating deep collapsible loess foundation

Technical Field

The utility model relates to the technical field of geotechnical engineering, in particular to a combined pile system for treating a deep collapsible loess foundation.

Background

Research on collapsible loess foundation treatment is always an important content in the field of geotechnical engineering, large-thickness collapsible loess is influenced by the accumulation environment, geographical position, geology and weather conditions of various regions, and the accumulation thickness and the engineering characteristics (such as collapsible property and the like) of the soil are obviously different. From the landform, the artificial foundation mainly distributes in loess sources, beams, mortises and river high-order areas, has the thickness of 10-40 m, strong collapsibility and self-weight collapsibility, and the collapsibility grade of the foundation is mostly III-IV grade, so that certain difficulty is brought to the treatment of the simulated building foundation.

The loess collapsibility phenomenon is a complicated physical and chemical change process. With the development of engineering construction in China, the construction of special structures on deep collapsible loess foundations is a normal state, and the structures have high requirements on foundation bearing capacity and settlement. The method is characterized in that the method is subject to the traditional collapsible loess foundation treatment mode, lime soil compaction piles are adopted for treatment, the soil among the piles is effectively compacted by controlling the distance between the piles, the loess collapsibility is eliminated, but the bearing capacity of the treated composite foundation does not meet the design requirement of the bearing capacity of the special structure foundation; the rigid piles with the same pile spacing are adopted for processing, and the construction cost is high.

Aiming at the deep collapsible loess foundation of a special road section, the utility model discloses a rigid and flexible combined treatment mode, which not only eliminates the collapsible loess, but also greatly improves the bearing capacity of the loess foundation.

SUMMERY OF THE UTILITY MODEL

Technical problem to be solved

Aiming at the defects of the prior art, the utility model provides a combined pile system for treating a deep collapsible loess foundation, which solves the problem of limitation of treating the deep collapsible loess foundation by a single pile type.

(II) technical scheme

In order to achieve the purpose, the utility model is realized by the following technical scheme: the utility model provides a combination pile system to deep collapsible loess foundation treatment, includes crowded close stake of grey soil, PTC tubular pile cap, 5% grey soil bed course and collapsible loess, 5% grey soil bed course is inlayed at collapsible loess top surface, the bottom of 5% grey soil bed course is provided with crowded close stake of multirow grey soil and PTC tubular pile in turn, through the horizontal extrusion of pore-forming in-process, the downthehole soil of stake is crowded to around, makes the stake soil can be crowded close, eliminates the collapsible nature of yellow soil, crowded close stake of grey soil and PTC tubular pile insert in collapsible loess, the top of PTC tubular pile is provided with PTC tubular pile cap, PTC tubular pile cap inlays the bottom at 5% grey soil bed course.

Preferably, the pile body reinforcing steel bar of PTC tubular pile anchors into PTC tubular pile cap and welds with the main muscle of PTC tubular pile cap, the anchor depth of penetration is not less than 5cm, makes the tubular pile bear main upper portion load, improves foundation bearing capacity by a wide margin. And a 50cm lime soil cushion layer is arranged at the top of the combined pile, so that the pile and the soil between the piles act together.

Preferably, the thickness of the 5% lime soil pad layer is 0.5 m.

Preferably, the collapsible loess has a thickness of not less than 25 m.

Preferably, the pile body diameter of the lime-soil compaction pile and the PTC tubular pile is 0.4m, and the distance between the lime-soil compaction pile and the PTC tubular pile is 1.2 m.

Preferably, the size of the PTC tubular pile cap is 1.5m by 0.2 m.

(III) advantageous effects

The utility model provides a combined pile system for treating a deep collapsible loess foundation. The method has the following beneficial effects:

this combination pile system PTC tubular pile to deep collapsible loess foundation treatment adopts the mode of driving into to implement to the interval replaces traditional single lime soil compaction stake arrangement mode, full play stake to the horizontal extrusion effect of soil between the stake, set up pile cap, lime soil bed course through the pile bolck, increased substantially composite foundation bearing capacity, provide a new processing scheme for special highway section deep collapsible loess foundation. The utility model not only reduces the engineering cost, but also ensures the treatment effect.

Drawings

FIG. 1 is a perspective view of the structure of the present invention;

FIG. 2 is a schematic structural view of the present invention;

fig. 3 is a bottom view of the structure of the present invention.

In the figure: 1. compacting the piles by using lime soil; 2. PTC tubular piles; 3. a PTC tubular pile cap; 4. 5% lime soil cushion layer; 5. collapsible loess.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the 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.

Example (b):

as shown in fig. 1, 2 and 3, the present invention provides a combined pile system for deep collapsible loess foundation treatment, which comprises a lime soil compaction pile (1), a PTC tubular pile (2), a PTC tubular pile cap (3), a 5% lime soil cushion layer (4) and collapsible loess (5), wherein the 5% lime soil cushion layer (4) is laid on the top surface of the collapsible loess (5), and the combined pile system is characterized in that: the bottom of the 5% lime soil cushion layer (4) is alternately provided with a plurality of rows of lime soil compaction piles (1) and PTC tubular piles (2), the lime soil compaction pile (1) and the PTC tubular pile (2) are inserted into collapsible loess (5), the top of the PTC pipe pile (2) is provided with a PTC pipe pile cap (3), the PTC tubular pile cap (3) is embedded at the bottom of the 5% lime soil cushion layer (4), the pile body steel bar of the PTC pipe pile (2) is anchored into the PTC pipe pile cap (3) and is welded with the main bar of the PTC pipe pile cap (3), the anchoring depth is not less than 5cm, the thickness of the 5% lime soil cushion layer (4) is 0.5m, the thickness of the collapsible loess (5) is not less than 25m, the diameters of the lime soil compaction pile (1) and the pile body of the PTC tubular pile (2) are 0.4m, the interval between the lime-soil compaction pile (1) and the PTC tubular pile (2) is 1.2m, and the size of the PTC tubular pile cap (3) is 1.5m by 0.2 m.

In this embodiment, the collapsible loess 5 field is leveled first.

In the embodiment, the field is measured and set out, a control axis and a field side line are determined, hole sites of the lime soil compaction piles 1 and the PTC tubular piles 2 are arranged at intervals in a plum blossom shape and are marked, and the distance between the combined piles is 1.2 m.

In this embodiment, the lime-soil compaction pile 1 is formed by hammering a steel pipe into soil to laterally compact a soil body to form a pile hole, tamping the bottom of the hole after forming the hole, and then backfilling the pile hole in layers 3: 7, tamping the lime soil, wherein the pile top is higher than the designed elevation by 15cm, and the higher part is removed before the cushion layer is laid.

In this embodiment, the PTC tubular pile 2 is a prestressed concrete thin-wall tubular pile, and the pile is sunk by static pressure of the pile pressing machine, and the verticality control of the tubular pile is the key to ensure the pile sinking quality, so that a specially-assigned person can be arranged to monitor by using a total station.

In the embodiment, after the PTC tubular pile 2 is driven to the designed position and is qualified through inspection, the soil mould excavation of the PTC tubular pile cap 3 can be carried out, the pile body steel bar of the PTC tubular pile 2 is anchored into the pile cap and is welded with the main steel bar of the PTC tubular pile cap 3, the plate appearance size of the PTC tubular pile cap 3 is 1.5m, the thickness is 0.2m, and the length of the PTC tubular pile 2 extending into the PTC tubular pile is more than or equal to 5 cm.

In the embodiment, after the PTC tubular pile cap 3 is maintained to meet the strength requirement, the field is leveled again, and then a 5% lime soil cushion layer 4 with the thickness of 0.5m is laid on the whole field.

In conclusion, the PTC tubular pile of the combined pile system for treating the deep collapsible loess foundation is implemented in a driving mode, the traditional single lime soil compaction pile arrangement mode is replaced at intervals, the transverse extrusion effect of piles on soil among piles is fully exerted, the pile caps and the lime soil cushion layers are arranged on the pile tops, the bearing capacity of the composite foundation is greatly improved, and a new treatment scheme is provided for the deep collapsible loess foundation of a special road section. The utility model not only reduces the engineering cost, but also ensures the treatment effect.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides a combination stake system to deep collapsible loess foundation is handled, includes lime soil compaction stake (1), PTC tubular pile (2), PTC tubular pile cap (3), 5% lime soil bed course (4) and collapsible loess (5), 5% lime soil bed course (4) are laid at collapsible loess (5) top surface, its characterized in that: the bottom of 5% lime soil bed course (4) is provided with multirow lime soil compaction stake (1) and PTC tubular pile (2) in turn, the lime soil compaction stake (1) and PTC tubular pile (2) are inserted in collapsible loess (5), the top of PTC tubular pile (2) is provided with PTC tubular pile cap (3), inlay the bottom in 5% lime soil bed course (4) in PTC tubular pile cap (3).

2. The composite pile system for the deep collapsible loess foundation treatment according to claim 1, wherein: pile body reinforcing steel bar anchor of PTC tubular pile (2) goes into PTC tubular pile cap (3) and welds with the main muscle of PTC tubular pile cap (3), the degree of depth that the pile body reinforcing steel bar anchor of PTC tubular pile (2) goes into PTC tubular pile cap (3) is not less than 5 cm.

3. The composite pile system for the deep collapsible loess foundation treatment according to claim 1, wherein: the thickness of the 5% lime soil cushion layer (4) is 0.5 m.

4. The composite pile system for the deep collapsible loess foundation treatment according to claim 1, wherein: the collapsible loess (5) has a thickness of not less than 25 m.

5. The composite pile system for the deep collapsible loess foundation treatment according to claim 1, wherein: the pile body diameter of the lime-soil compaction pile (1) and the PTC tubular pile (2) is 0.4m, and the distance between the lime-soil compaction pile (1) and the PTC tubular pile (2) is 1.2 m.

6. The composite pile system for the deep collapsible loess foundation treatment according to claim 1, wherein: the size of the PTC tubular pile cap (3) is 1.5m 0.2 m.