CN215483067U

CN215483067U - Pillar foundation structure of contact net

Info

Publication number: CN215483067U
Application number: CN202120693122.9U
Authority: CN
Inventors: 胡健; 沈磊; 向福稳; 吴亮; 孙阊禹
Original assignee: China Railway Siyuan Survey and Design Group Co Ltd
Current assignee: China Railway Siyuan Survey and Design Group Co Ltd
Priority date: 2021-04-06
Filing date: 2021-04-06
Publication date: 2022-01-11
Anticipated expiration: 2031-04-06

Abstract

The application discloses pillar foundation structure of contact net includes: the upper end of the supporting part is used for mounting a strut of the overhead line system; a pile foundation part, the upper end of which is connected to the lower end of the support part; and the waterproof curtain is connected with the lower part of the supporting part and surrounds the pile foundation part. The utility model provides a pillar foundation structure of contact net, the excavation depth is shallower, and the excavation area is less, has improved the vertical bearing capacity and the antidumping ability of the pillar foundation structure of railway contact net, has reduced the influence of construction contact net pillar foundation structure to surrounding environment, has especially reduced to the existing line operation risk of railway and has had a risk and safe risk.

Description

Pillar foundation structure of contact net

Technical Field

The application relates to the technical field of railway roadbed engineering, in particular to a strut foundation structure of a contact net.

Background

The high-speed railway contact net is a transmission line which is erected along the railway line and supplies power to an electric locomotive. It is composed of contact suspension, supporting device, positioning device, supporting column and supporting column base. The structure and the construction quality of the strut foundation of the contact network directly influence the transportation capacity of the electrified railway of the contact network. The contact net support foundation can be divided into an expanded foundation and a pile foundation, and the construction of the expanded foundation is large in excavation surface and shallow in excavation depth; the pile foundation construction has small excavation surface and deep excavation depth. Under the general condition, the newly-built railway can be based on different geological conditions, the reasonable pillar basis of selecting. Under the condition of a hard crossing contact net structure foundation newly built along the adjacent existing railway, the existing railway subgrade and the cable trench can be directly influenced by adopting the two types of strut foundation construction, and railway operation interruption can be caused. Therefore, the existing structural form has a great risk when the strut foundation of the overhead line system is constructed under the condition that the existing line operation is not influenced.

SUMMERY OF THE UTILITY MODEL

In view of this, the application provides a contact net pillar foundation structure to reduce the influence of construction to the surrounding environment.

In order to achieve the above object, an aspect of the embodiments of the present application provides a strut foundation structure of a catenary, including:

the upper end of the supporting part is used for mounting a strut of the overhead line system;

a pile foundation part, the upper end of which is connected to the lower end of the support part; and

and the waterproof curtain is positioned below the supporting part and surrounds the pile foundation part.

Further, the support portion includes:

the upper end of the supporting column is used for mounting the supporting column; and

the upper end of the expansion column is connected to the lower end of the support column, the cross-sectional area of the expansion column is gradually increased from the support column downwards, and the upper end of the pile foundation part is connected to the lower end of the expansion column.

Further, the waterproof curtain includes:

and the supporting piles are meshed or continuously annularly arranged to surround the pile foundation part.

Further, the upper end of the support pile is connected with the lower end of the support part, and the lower end of the support pile extends along the direction gradually far away from the pile foundation part.

Further, the pile foundation portion includes:

the upper end of the hole digging pile is connected with the lower end of the supporting part; and

and the protecting wall is positioned on the inner side of the waterproof curtain and surrounds the hole digging pile.

Further, the hole digging pile comprises a straight hole section positioned above and an expanding hole section connected below, and the cross-sectional area of the expanding hole section is larger than that of the straight hole section.

The application provides a pair of contact net pillar foundation structure, owing to synthesize the structure that adopts supporting part and pile foundation portion, the excavation area of supporting part is less, the excavation depth of pile foundation portion is more shallow, adopt the stagnant water curtain simultaneously, strengthen the soil body on every side, reduce because of groundwater flows in to the disturbance of existing road bed or excavation in-process collapse, the influence of construction pillar foundation structure to the surrounding environment has been reduced, especially, the existing line operation risk and the safety risk to the railway have been reduced, the vertical bearing capacity and the antidumping ability of the pillar foundation structure of railway contact net have been improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a schematic longitudinal section of a catenary strut substructure according to an embodiment of the present disclosure;

FIG. 2 is a schematic top view of FIG. 1;

FIG. 3 is a cross-sectional view in the direction A-A of the embodiment shown in FIG. 1;

FIG. 4 is a cross-sectional view in the direction A-A of another embodiment shown in FIG. 1; and

fig. 5 is a schematic view of a construction method of a contact net support foundation structure according to an embodiment of the present application.

Description of reference numerals:

1. a support portion; 2. a pile foundation portion; 3. a waterproof curtain; 4. a support layer; 11. a support pillar; 12. an extension column; 21. protecting the wall; 22. digging a hole pile; 31. supporting piles; 111. a pedestal bolt; 112. a column shoe bottom plate; 311. a guniting hole; 221. a straight hole section; 222. and (4) a hole expanding section.

Detailed Description

It should be noted that the various embodiments/implementations provided in this application can be combined with each other without contradiction. The detailed description in the specific embodiments should be understood as an illustration of the spirit of the application and not as an undue limitation of the application.

In the description of the present application, the "up", "down", "top" and "bottom" orientation or positional relationship is the description of the strut foundation structure of the catenary in the normal use state, and based on the orientation or positional relationship shown in fig. 1, "horizontal" is the left-right direction of fig. 1, and "vertical" is the up-down direction of fig. 1. It is to be understood that such directional terms are merely for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the present application. The term "first/second" merely distinguishes between different objects and does not denote the same or a relationship between the two.

As part of the inventive concept of the present application, before describing the embodiments of the present application, a concrete analysis is performed by taking the construction situation of the strut foundation structure of the railway contact network in the prior art as an example, and the strut foundation structure of the newly-built railway contact network in the prior art can be constructed by adopting an extended foundation or a pile foundation.

When an extended foundation is adopted, a larger excavation surface is required in order to meet the requirement of overturning resistance of the railway contact network structure. If the newly-built expansion support foundation is close to the existing railway facility, the existing railway roadbed and the cable trench can be directly damaged by large-area construction and excavation, railway operation interruption can be caused, and safety risks are caused to the existing line operation.

When the pile foundation is adopted, construction conditions are limited, the pile driving equipment is difficult to construct near the existing line, in order to meet the requirement of overturning resistance of a railway contact network structure, only manual hole digging piles can be adopted for digging, the depth of the manually dug pile foundation is deep, the risk of collapse exists, the personal safety of workers in the hole is seriously threatened, meanwhile, the permeable water caused by high underground water level can cause the subgrade settlement to threaten the operation of the existing line, and therefore, the implementation conditions are not met under the conditions of poor geological conditions and high underground water level.

In view of the above, an aspect of the embodiments of the present application provides a strut foundation structure of a catenary, as shown in fig. 1, including a support portion 1, a pile foundation portion 2, and a waterproof curtain 3. The upper end of supporting part 1 is used for installing the pillar of contact net, and the upper end of pile foundation portion 2 is connected to the lower extreme of supporting part 1, and waterproof curtain 3 is located the below of supporting part 1, and waterproof curtain 3 encloses and establishes pile foundation portion 2 for prevent or reduce foundation ditch lateral wall groundwater and flow in, reduce the disturbance to existing road bed, guarantee simultaneously that pile foundation portion 2 can safe construction down. Specifically, the waterproof curtain 3 may be connected to the lower end of the support part 1 to form an integral structure with the support part 1, so as to improve the bearing capacity and the anti-overturning capacity of the pillar base structure. In other embodiments, the waterproof curtain 3 may not be connected to the support part 1.

In an embodiment of the present application, referring to fig. 1 and 2, the supporting portion 1 includes a supporting column 11 and an expansion column 12, an upper end of the expansion column 12 is connected to a lower end of the supporting column 11, and a cross-sectional area of the expansion column 12 is gradually increased from top to bottom, so that an anti-overturning capability of the pillar foundation structure is improved.

In order to facilitate the construction of the contact net support, the upper end of the support column 11 is further provided with a column base bottom plate 112 and a column base bolt 111, the lower end of the column base bolt 111 is embedded in the support portion 1, a plurality of bolt holes are formed in the column base bottom plate 112, and the column base bottom plate 112 penetrates through the bolt holes in the column base bottom plate 112 through the column base bolt 111 and is fixed on the support column 11.

In an embodiment of the present application, referring to fig. 1, 3 to 4, the waterproof curtain 3 includes a support pile 31, and the support pile 31 is located below the support part 1. Specifically, the upper end of the support pile 31 may be connected to the bottom surface of the lower end of the extension column 12, and the plurality of support piles 31 are enclosed outside the pile foundation portion 2 and extend in a direction gradually away from the pile foundation portion 2, so as to further improve the bearing capacity and the anti-overturning capacity of the pillar foundation structure.

The surface of the pile hole of the supporting pile 31 is also provided with a guniting hole 311, after the supporting pile 31 is grouted, concrete grout can be injected into the soil body around the supporting pile 31 through the guniting hole 311, and the concrete grout in the soil body around the supporting pile can be condensed to form a reinforced soil body after reaching the design strength, so that the reinforced soil body can be used as the waterproof curtain 3 of the pile foundation part 2. The reinforced soil body formed by the waterproof curtain 3 can prevent or reduce the inflow of underground water on the side wall of the foundation pit, and meanwhile, the reinforced soil body has certain structural strength, so that the disturbance to the existing roadbed is reduced, and especially, the safety construction of the subsequent pile foundation part 2 of the stratum with higher underground water level and poorer geological conditions is guaranteed.

In an embodiment of the present application, referring to fig. 3, the supporting piles 31 forming the waterproof curtain 3 may be configured as snap piles and annularly arranged outside the pile foundation portion 2, and the number of layers of the snap piles may be increased or decreased according to geological conditions.

In another embodiment of the present application, referring to fig. 4, the supporting piles 31 forming the waterproof curtain 3 may be provided as continuous piles annularly arranged outside the pile foundation 2, and the number of the continuous piles may be increased or decreased according to geological conditions.

In an embodiment of the present application, referring to fig. 1, the pile foundation 2 includes a bored pile 22 and a retaining wall 21, and an upper end of the bored pile 22 is connected to a lower end of the extension column 12 in the support 1; the dug pile 22 further comprises a straight hole section 221 positioned above and an expanded hole section 222 connected below, wherein the cross-sectional area of the expanded hole section 222 is larger than that of the straight hole section 221. By reaming the underside of the bored pile 22 to form a reamed section 222, the vertical load bearing capacity and the resistance to overturning of the column substructure may be further improved.

The retaining wall 21 is arranged on the inner side of the support pile 31 forming the waterproof curtain 3 and on the outer side of the straight hole section 221, the retaining wall 21 is constructed while the hole digging pile 22 is dug, and the retaining wall 21 can play a role in protecting the hole digging pile 22 and preventing the collapse of the surrounding soil body.

In the strut foundation structure of the contact network implemented by the embodiment of the application, the supporting part 1 is constructed by adopting an expanded foundation with a larger excavation surface than a single supporting part, and the excavation surface is smaller; the pile foundation part 2 has a shallower pile foundation depth compared with the pile foundation construction which independently adopts a deep pile foundation depth; set up simultaneously waterproof curtain 3 and further promote the construction security and the structural reliability of pillar basis, under the condition of guaranteeing safe construction, can adjust excavation face and excavation degree of depth simultaneously according to actual engineering needs, reduce the influence to the surrounding environment comprehensively, for example to the influence of existing line operation, have stronger economic nature and practicality, especially provide a good solution for closing on the difficult problem of constructing of contact net pillar basis.

In another aspect of the embodiments of the present application, referring to fig. 5, there is provided a method for constructing a foundation structure of a pillar, including:

s1: excavating a soil body to a preset first depth to form a first pit bottom;

s2: constructing supporting pile holes at the bottom of the first pit, wherein the supporting pile holes are distributed in an annular shape;

s3: grouting into the support pile hole to form a waterproof curtain;

s4: excavating downwards along the first pit bottom in the waterproof curtain to a second depth to form a second pit bottom;

s5: placing the steel bars of the pile foundation part in the second depth, and grouting to form the pile foundation part;

s6: and placing the steel bars of the supporting part in the first depth, and grouting to form the supporting part.

The following is a detailed description of the steps of the construction method of the column foundation structure according to the embodiment of the present application.

S1: and excavating the soil body to a preset first depth to form a first pit bottom.

Referring to fig. 1, in the position where the pillar foundation structure needs to be set, a proper excavation surface can be set according to actual working conditions, soil excavation is performed in the forms of manual excavation or mechanical excavation and the like reasonably, the soil excavation is performed to a preset first depth, a first pit bottom is formed, and a supporting pile 31 of a supporting part 1 and a waterproof curtain 3 is conveniently and subsequently arranged. Specifically, when construction is performed near existing lines of a railway, manual excavation of earth can be adopted.

S2: and constructing supporting pile holes at the bottom of the first pit, wherein the supporting pile holes are distributed in a ring shape.

Referring to fig. 1, the support pile hole is formed at the bottom of the expansion column 12 in the support part 1, and the construction of the support pile hole can be reasonably performed by adopting, but not limited to, drilling modes including rotary drilling, percussion drilling and rotary drilling according to actual working conditions. The drilling direction can set up to extend to the outside along pile foundation portion 2 and to the direction of keeping away from pile foundation portion 2 gradually, and a plurality of support piles 31 that set up through this kind of mode can make waterproof curtain 3 have great stagnant water scope, have further improved the anti-overturning ability of the vertical bearing capacity of contact net pillar foundation structure.

Referring to fig. 3 and 4, the supporting pile holes are distributed in a ring shape, and the diameter of the surrounding ring is larger than that of the pile foundation part 2, so as to form the waterproof curtain 3 for protecting the pile foundation part 2, and the holes can be drilled in any combination of, but not limited to, snap piles, continuous piles, single-layer piles or multiple-layer piles according to actual working conditions.

S3: grouting into the support pile hole to form a waterproof curtain.

Referring to fig. 1, a support pile 31 is formed by grouting into a support pile hole, the support pile 31 annularly surrounds a pile foundation 2, a guniting hole 311 is further formed in the surface of the support pile 31, after grouting of the support pile 31, concrete grout can be injected into soil around the support pile 31 through the guniting hole 311, and the reinforced soil formed after the concrete grout in the surrounding soil is condensed to reach the designed strength is combined with a support pile 31 enclosing structure, so that the waterproof curtain 3 of the pile foundation 2 can be formed.

S4: and excavating downwards along the first pit bottom in the waterproof curtain to a second depth to form a second pit bottom.

Referring to fig. 1, according to actual working conditions, soil excavation in forms of manual excavation or mechanical excavation and the like can be reasonably selected, and when the manual excavation is adopted, a protective wall 21 can be arranged for protection to prevent soil around a hole wall from collapsing. And excavating the soil body to a preset second depth to form a second pit bottom. In order to ensure that the pile foundation has better vertical bearing capacity, the preset second depth can be excavated to the depth range shown by the bearing layer 4, for example, the excavation is preset to the depth range of one meter or more from the bearing layer 4, so that the pile foundation part 2 can be conveniently and subsequently arranged. Specifically, when construction is performed near existing lines of a railway, manual excavation of earth can be adopted.

S5: and placing the steel bars of the pile foundation part in the second depth, and grouting to form the pile foundation part.

Referring to fig. 1, the steel bars of the pile foundation portion 2 are placed in the second depth, grouting is performed to form the pile foundation portion 2, the extending end of the steel bars of the pile foundation portion 2 is anchored in the expansion column 12, the lower end of the pile foundation portion 2 can be provided with a reaming section 222 with a larger cross-sectional area, the cross-sectional area of the reaming section 222 is larger than that of the straight hole section 221, and the reaming section 222 can further improve the vertical bearing capacity and the anti-overturning capacity of the pillar foundation structure.

Referring to fig. 1 and 2, the support portion 1 includes a support column 11 and an expansion column 12, and a bottom surface of the expansion column 12 is higher than a slope starting point. Placing the reinforcing bar of extension post 12 earlier and then placing the reinforcing bar of support column 11, the reinforcing bar setting of support column 11 is in the reinforcing bar top of extension post 12, and from lower up slip casting forms extension post 12 and support column 11 to form whole supporting part 1.

The support column 11 upper end still is equipped with column base bottom plate 112 and column base bolt 111, is formed with a plurality of bolt holes on the column base bottom plate 112, penetrates bolt hole and the reinforcement on the supporting part 1 through column base bolt 111, fixes column base bottom plate 112 on support column 11, forms holistic support column 11 after the slip casting. Through the mode of fixing earlier, integral casting again, support column 11 structural wholeness is high, has reduced follow-up step to support column 11 drilling fixed column foot bottom plate 112, has avoided leading to support column 11 structural cracking, drilling to hit a series of problems such as reinforcing bar because of the drilling, has the pillar basis of foot bottom plate 112 simultaneously, the construction of the contact net pillar of being convenient for.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A strut substructure for an overhead line system, comprising:

2. The strut foundation structure of claim 1, wherein the support portion comprises:

3. The column substructure of claim 1, wherein the waterproof curtain comprises:

4. The column foundation structure of claim 3, wherein the upper ends of the support piles are connected to the lower ends of the support parts, and the lower ends of the support piles extend in a direction gradually away from the pile foundation part.

5. The column substructure of claim 1, wherein the pile foundation section comprises:

6. The column substructure of claim 5, wherein said dug pile comprises a straight section above and an expanded section connected below, said expanded section having a cross-sectional area greater than the cross-sectional area of said straight section.