CN112664205B - Tunnel excavation supporting method for cross intersection - Google Patents
Tunnel excavation supporting method for cross intersection Download PDFInfo
- Publication number
- CN112664205B CN112664205B CN202011584879.0A CN202011584879A CN112664205B CN 112664205 B CN112664205 B CN 112664205B CN 202011584879 A CN202011584879 A CN 202011584879A CN 112664205 B CN112664205 B CN 112664205B
- Authority
- CN
- China
- Prior art keywords
- steel arch
- hole
- supporting
- steel
- support
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
Landscapes
- Lining And Supports For Tunnels (AREA)
Abstract
The invention discloses a supporting method for tunnel excavation at a cross intersection. The invention firstly excavates the main hole and carries out steel arch centering and anchor spraying support. When the cross passes back, supporting the top steel arch for supporting the cross, then sequentially locking the steel arch for supporting holes on two sides of the cross, and excavating and supporting forward, wherein all the supporting closely follows the tunnel face. The cross intersection adopts to prop a steel arch frame and the two sides prop a hole fore shaft and adopt the closed loop fore shaft steel arch frame that three pin I-steel are connected side by side, prop a steel arch frame and provide the guarantee to the stability of hole top, the fore shaft steel arch frame once trades and prop in place, avoid the secondary support interference that subregion excavation brought, make the hole body once take shape excavation in place, and main hole and cross intersection both sides prop a hole and open the support order and clear, avoid cross construction influence, whole support is timely, stability and construction safety of the hole body have been ensured effectively, engineering investment has been reduced in the time of saving the time limit for a project.
Description
Technical Field
The invention relates to a tunnel excavation supporting method for a cross intersection in the field of buildings such as hydropower, highways and the like, in particular to a tunnel excavation supporting method for realizing safe construction of the cross intersection by replacing supporting through a steel arch in tunnel excavation constructed by a drilling and blasting method.
Background
With the continuous development of underground engineering in China, in the underground engineering construction of projects such as water conservancy and hydropower, traffic and the like, in order to meet engineering requirements, a fork structure becomes more and more complex, and even a cross is unavoidable. The large-section underground cavity plane cross intersection is complex in structure, large in excavation height and large in span, partition excavation is often needed to meet the traffic conditions and the thickness of the secondary lining structure in construction, and particularly the stability and safety problems of cavities in excavation supporting construction are particularly important under the condition that surrounding rock conditions are unfavorable. In the structure excavation supporting construction, the excavation working procedure and the supporting parameters are different, the unscientific excavation working procedure and the supporting parameters are easy to cause safety accidents such as settlement deformation, cracking and even collapse of the top arch, and the influence of the re-supporting tunnel on the structure construction safety, the construction period and the investment control is large.
Generally, the existing tunnel intersection excavation supporting relates to fewer tunnel excavation conditions of the intersection, the tunnel excavation supporting conditions of the intersection are complex, the tunnel openings are concentrated, the roof arch is easy to settle, and the construction cross influence is larger.
Disclosure of Invention
In order to solve the problems in the background, the invention provides a tunnel excavation supporting method for a large buried depth, a poor surrounding rock and a large-section cross intersection. On one hand, the risk of settlement deformation, cracking and collapse of the cavity is reduced, the construction safety is guaranteed, on the other hand, the construction is convenient, the construction progress is accelerated, and meanwhile, the engineering investment is saved.
In order to achieve the above purpose, the invention adopts the following technical scheme:
a tunnel excavation supporting method for a cross intersection comprises the following steps:
s1, designing 2 branch holes, namely a branch hole B and a branch hole C, in a position of a main hole A in the vertical direction of two sides, and chamfering and enlarging the intersection of the main hole A, the branch hole B and the branch hole C for facilitating traffic; excavating forwards along the main hole A to enter a cross intersection, and carrying out conventional supporting steel arch frames, system anchor rods, reinforcing steel bar meshes and concrete spraying supporting on the main hole A; the main hole A cross intersection is extended and dug to two sides for a certain distance, the supporting legs of the conventional supporting steel arch frame extend to the extended and dug sections at two sides correspondingly, and a space is reserved for facilitating the construction of the locking steel arch frames of the later-stage supporting holes B and C;
s2, returning to support the steel arch frame and the locking roof anchor rod of the cross intersection after the main hole A is excavated and passes through the cross intersection, so as to reduce roof arch settlement caused by the subsequent excavation of the support hole B and the support hole C;
s3, performing closed-loop locking steel arch construction on the support hole B;
s4, carrying out support changing welding connection on the closed-loop fore shaft steel arch of the support hole B and the conventional support steel arch of the prior main hole A, cutting off the conventional support steel arch part of the main hole A below the fore shaft steel arch top arch, and finally carrying out system anchor rod and shotcrete support on the fore shaft face of the support hole B;
s5, performing closed-loop fore shaft steel arch construction on the support hole C, performing support replacement welding connection on the fore shaft steel arch of the support hole C and the conventional support steel arch of the prior main hole A, cutting off the conventional support steel arch part of the main hole A below the fore shaft steel arch top arch, and finally performing system anchor rod and shotcrete support on the fore shaft tunnel face of the support hole C; and alternatively constructing each cycle of footage of the subsequent excavation sections of the main hole A, the branch hole B and the branch hole C.
The beneficial effects of the invention are as follows:
1) The method comprises the steps of firstly digging and supporting a main hole of a cross intersection, supporting a top steel arch frame of the cross intersection, then digging forward after the supporting and supporting of the locking steel arch frame of the supporting hole, strictly controlling the digging footage, and enabling the supporting to follow the face of the tunnel. Besides the conventional support of steel arches, system anchor rods, reinforcing steel bar meshes, sprayed concrete and the like, the cross intersection is additionally provided with a top steel arch, a top locking anchor rod and a supporting hole locking steel arch for support replacement connection, and the whole support is timely, so that the stability of a cavity and the safety of construction are ensured.
2) The cross intersection excavation supporting process is clear, the influence of cross construction is avoided, the locking steel arch frame is replaced in place once, secondary supporting interference caused by partition excavation is avoided, the hole body is formed and excavated in place once, the main hole A, the branch hole B and the branch hole C can be constructed alternately at each cycle of footage, the construction period is saved, and the engineering investment is reduced.
Drawings
FIG. 1 is a flow chart of the present invention;
FIG. 2 is a tunnel floor plan;
FIG. 3 is a sectional view A-A of FIG. 2;
FIG. 4 is a cross-sectional view B-B of FIG. 2;
FIG. 5 is a block diagram of a cross brace roof steel arch;
FIG. 6 is a detail view of FIG. 5, namely a detail view of the top connection of the cross brace roof arch;
FIG. 7 is a block diagram of a steel arch with a locked mouth for support B and support C;
FIG. 8 is a cross-sectional view C-C of FIG. 7, showing a detail view of the welded attachment of three joists of the arch steel;
fig. 9 is a detail view of fig. 7, namely, a detail view of the replacement and support connection of the steel arch of the support hole locking notch and the conventional support steel arch of the main hole A.
In the figure: 1-a cross supporting structure; 11-a conventional supporting steel arch; supporting a steel arch at a 12-cross intersection; 13-locking a steel arch; 14-spraying concrete; 15-locking the roof bolt; 16-system anchor rods; 17-a reinforcing mesh; 18-I-steel corbels; 2-tunnel; 21-main hole A; 22-branch hole B; 23-branch hole C;12 a-supporting the I-steel of the steel arch; 12 b-supporting a steel arch frame connecting steel plate; 12 c-supporting a steel arch frame erection steel plate; 12 d-welding backing plates; 12 e-connecting steel plates; 12 f-high-strength connecting bolts; 13 a-the I-steel of the locking notch steel arch of three side-by-side truss; 13 b-locking steel arch frame connecting steel plates; 13 c-locking a steel arch frame erection steel plate; 13d-Q235B is attached to the panel.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
The invention relates to a method for excavating and supporting tunnels at a cross intersection, which comprises the following specific steps of:
s1, as shown in FIG. 2, a cross intersection supporting structure 1 of a tunnel 2 consists of a main hole A21, two side vertical supporting holes B22 and a supporting hole C23, and chamfering and expanding digging are carried out on the intersection of the main hole A21, the supporting holes B22 and the supporting holes C23 for facilitating traffic; as shown in fig. 3 to 4, a conventional supporting steel arch 11, a system anchor rod 16, a reinforcing mesh 17 and a sprayed concrete 14 are excavated and constructed along a main hole a 21;
s2, when the main hole A21 excavates and supports and passes through the cross, returning to support the cross supporting steel arch 12 and implement the locking roof bolt 15; as shown in fig. 5, the supporting steel arch 12 of the cross intersection is formed by welding and connecting supporting steel arch I-steel 12a with supporting steel arch connecting steel plates 12b and supporting steel arch erecting steel plates 12 c; the top connection detail diagram of the propping steel arch 12 is shown in fig. 6, and two cross propping steel arches 12 are firmly connected through a welding backing plate 12d, a connecting steel plate 12e and a high-strength connecting bolt 12 f;
s3, supporting the support hole B22 by using the locking steel arch 13; as shown in fig. 7, the fore shaft steel arch 13 is composed of fore shaft steel arch i-steel 13a, fore shaft steel arch connecting steel plate 13B, fore shaft steel arch erecting steel plate 13c and Q235B connecting lacing plates 13d of three side by side, wherein the fore shaft steel arch i-steel 13a of the three side by side is welded with the fore shaft steel arch connecting steel plate 13B and the fore shaft steel arch erecting steel plate 13 c; as shown in fig. 8, the sides of the I-steel 13a and the Q235B of the fore shaft steel arch of the three side-by-side truss are welded and fixed;
s4, as shown in FIG. 9, the fore shaft steel arch 13 needs to be in support changing connection with the conventional supporting steel arch 11 of the main hole A21 at the adjacent position, the fore shaft steel arch 13 and the conventional supporting steel arch 11 are subjected to overlap joint gap welding with the I-shaped steel corbel 18, and then the conventional supporting steel arch 11 part of the main hole A21 below the vault of the fore shaft steel arch 13 of the supporting hole B22 is cut off; finally locking the tunnel B22 to form the tunnel face supporting system anchor rod 16 and the sprayed concrete 14;
s5, supporting the fore shaft steel arch 13 of the support hole C23, wherein the fore shaft steel arch 13 is required to be in support changing connection with the conventional support steel arch 11 of the main hole A21 at the adjacent position, welding the I-shaped steel corbel 18 at the lap joint gap of the fore shaft steel arch 13 and the conventional support steel arch 11, and then cutting off the conventional support steel arch 11 of the main hole A21 below the vault of the fore shaft steel arch 13 of the support hole C23; finally locking the tunnel C23, the tunnel face supporting system anchor rod 16 and the sprayed concrete 14; and alternatively constructing each cycle of the subsequent excavation sections of the main hole A21, the branch hole B22 and the branch hole C23.
Claims (5)
1. The tunnel excavation supporting method for the cross intersection is characterized by comprising the following steps of: it comprises the following steps:
s1, designing 2 branch holes, namely a branch hole B and a branch hole C, in a position of a main hole A in the vertical direction of two sides, and chamfering and enlarging the intersection of the main hole A, the branch hole B and the branch hole C for facilitating traffic; excavating forwards along the main hole A to enter a cross intersection, and carrying out conventional supporting steel arch frames, system anchor rods, reinforcing steel bar meshes and concrete spraying supporting on the main hole A; the main hole A cross intersection is extended and dug to two sides for a certain distance, the supporting legs of the conventional supporting steel arch frame extend to the extended and dug sections at two sides correspondingly, and a space is reserved for facilitating the construction of the locking steel arch frames of the later-stage supporting holes B and C;
s2, returning to support the steel arch frame and the locking roof anchor rod of the cross intersection after the main hole A is excavated and passes through the cross intersection, so as to reduce roof arch settlement caused by the subsequent excavation of the support hole B and the support hole C;
s3, performing closed-loop locking steel arch construction on the support hole B;
s4, carrying out support changing welding connection on the closed-loop fore shaft steel arch of the support hole B and the conventional support steel arch of the prior main hole A, cutting off the conventional support steel arch part of the main hole A below the fore shaft steel arch top arch, and finally carrying out system anchor rod and shotcrete support on the fore shaft face of the support hole B;
s5, performing closed-loop fore shaft steel arch construction on the support hole C, performing support replacement welding connection on the fore shaft steel arch of the support hole C and the conventional support steel arch of the prior main hole A, cutting off the conventional support steel arch part of the main hole A below the fore shaft steel arch top arch, and finally performing system anchor rod and shotcrete support on the fore shaft tunnel face of the support hole C.
2. The tunnel excavation supporting method for a crossroad of claim 1, wherein: and S5, alternately constructing each cycle of footage of the subsequent excavation sections of the main hole A, the branch hole B and the branch hole C.
3. The tunnel excavation supporting method for a crossroad of claim 1, wherein: in the step S2, the supporting steel arch of the cross intersection is formed by welding and connecting supporting steel arch connecting steel plates and supporting steel arch erecting steel plates through supporting steel arch I-beams; the supporting steel arch frame is two roof trusses, and the crossing points of the two roof supporting steel arch frames are fixedly connected through a welding backing plate, a connecting steel plate and a high-strength connecting bolt.
4. The tunnel excavation supporting method for a crossroad of claim 1, wherein: the fore shaft steel arch consists of fore shaft steel arch I-steel of three side-by-side frames, fore shaft steel arch connecting steel plates, fore shaft steel arch frame standing steel plates and connecting batten plates, wherein the fore shaft steel arch I-steel of the three side-by-side frames is welded with the fore shaft steel arch connecting steel plates and the fore shaft steel arch frame standing steel plates; the I-steel of the fore shaft steel arch of the three side by side is welded and fixed with the periphery of the connecting batten plate.
5. The tunnel excavation supporting method for a crossroad of claim 1, wherein: the support-changing welding connection is to weld the I-shaped steel corbel at the lap joint gap of the fore shaft steel arch and the conventional support steel arch.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011584879.0A CN112664205B (en) | 2020-12-28 | 2020-12-28 | Tunnel excavation supporting method for cross intersection |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011584879.0A CN112664205B (en) | 2020-12-28 | 2020-12-28 | Tunnel excavation supporting method for cross intersection |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112664205A CN112664205A (en) | 2021-04-16 |
| CN112664205B true CN112664205B (en) | 2023-04-21 |
Family
ID=75411327
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011584879.0A Active CN112664205B (en) | 2020-12-28 | 2020-12-28 | Tunnel excavation supporting method for cross intersection |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112664205B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115045667A (en) * | 2022-06-17 | 2022-09-13 | 中建八局第三建设有限公司 | Safe construction method for T-shaped intersection of tunnel with super-large section |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107387131A (en) * | 2017-08-30 | 2017-11-24 | 中国电建集团中南勘测设计研究院有限公司 | A kind of asymmetric trouble hole supporting construction and its construction method |
| CN107762529B (en) * | 2017-12-09 | 2019-03-05 | 中铁二十局集团第二工程有限公司 | Lateral Hole and tunnel main tunnel infall construction method based on gib system |
| CN208763672U (en) * | 2018-07-30 | 2019-04-19 | 中国电建集团华东勘测设计研究院有限公司 | A kind of arch frame structure for tunnel intersection under complex geological condition |
-
2020
- 2020-12-28 CN CN202011584879.0A patent/CN112664205B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN112664205A (en) | 2021-04-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106337686B (en) | Three layers of subway station canopy structure of rocky stratum tunneling and construction method | |
| CN111188629B (en) | Construction method for sudden change of tunnel bifurcation section and expanding excavation | |
| CN109372518B (en) | Reverse excavation construction method for tunnel abrupt-change section | |
| CN104653187B (en) | Method for excavating geological large-section tunnel with water-rich sand layer | |
| CN204729099U (en) | Rock quality layer tunneling three layers of subway station canopy structure | |
| CN203879506U (en) | Supporting structure system for large-section deep vertical shaft in rock stratum | |
| CN108868834B (en) | Temporary support device for tunnel arch wall primary support intrusion limit arch changing construction | |
| CN112780286A (en) | Construction method for rapid expanding excavation conversion when tunnel section suddenly changes into large-span section | |
| CN113586068B (en) | Equal-height tunnel intersection excavation supporting construction method | |
| CN112664205B (en) | Tunnel excavation supporting method for cross intersection | |
| CN112302686B (en) | Vertical jacking construction method for entering tunnel inclined shaft into main tunnel | |
| CN112682048B (en) | Replacement reinforcement construction method for small clear distance up-span existing tunnel of newly-built tunnel | |
| CN112814686B (en) | Construction method for transverse expansion and excavation conversion during abrupt change of large-span section of tunnel section | |
| CN213898991U (en) | Combined supporting structure system for realizing large-span and small-clear-distance tunnel | |
| CN112253176A (en) | Combined supporting structure system for realizing large-span and small-clear-distance tunnel and construction method thereof | |
| CN115977696A (en) | Soft rock tunnel intersection supporting construction method | |
| CN215057408U (en) | Reinforcing device for intersection of inclined shaft and main tunnel of highway tunnel | |
| CN115467690A (en) | Shallow-buried large-span underground excavation subway station new structure system and construction method thereof | |
| CN113294178B (en) | Combined support system for extremely-broken surrounding rock tunnel and construction method thereof | |
| CN111236961B (en) | Construction method of expandable mudstone orthogonal inclined shaft detachable portal frame | |
| CN211058800U (en) | Water-rich weak surrounding rock tunnel excavation construction structure passing through fault fracture zone | |
| CN114320317A (en) | Construction method for weak surrounding rock section of short-step super-large section tunnel | |
| CN108843339B (en) | The auxiliary slip casting platform and construction method of large-scale solution cavity are passed through when existing tunnel digs | |
| CN112302687A (en) | Support-changing and jacking construction method for entering main tunnel of tunnel inclined shaft | |
| CN111075453A (en) | Excavation method for reducing tunnel deformation and mud inrush and water inrush |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: 310002, No. 66, Funing lane, Shangcheng District, Zhejiang, Hangzhou Applicant after: Zhejiang water resources and Hydropower Survey and Design Institute Co.,Ltd. Address before: 310002, No. 66, Funing lane, Shangcheng District, Zhejiang, Hangzhou Applicant before: ZHEJIANG DESIGN INSTITUTE OF WATER CONSERVANCY & HYDROELECTRIC POWER |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |