CN112502730A - Steel arch frame for preventing collapse of roadway at underground rock crushing section and supporting method thereof - Google Patents
Steel arch frame for preventing collapse of roadway at underground rock crushing section and supporting method thereof Download PDFInfo
- Publication number
- CN112502730A CN112502730A CN202011246647.4A CN202011246647A CN112502730A CN 112502730 A CN112502730 A CN 112502730A CN 202011246647 A CN202011246647 A CN 202011246647A CN 112502730 A CN112502730 A CN 112502730A
- Authority
- CN
- China
- Prior art keywords
- arch
- steel
- support
- arch frame
- roadway
- 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.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 133
- 239000010959 steel Substances 0.000 title claims abstract description 133
- 239000011435 rock Substances 0.000 title claims abstract description 30
- 238000000034 method Methods 0.000 title claims abstract description 20
- 238000009434 installation Methods 0.000 claims description 10
- 238000003466 welding Methods 0.000 claims description 8
- 238000009412 basement excavation Methods 0.000 claims description 6
- 239000011378 shotcrete Substances 0.000 claims description 6
- 230000001681 protective effect Effects 0.000 claims description 4
- 238000004080 punching Methods 0.000 claims description 3
- 238000005507 spraying Methods 0.000 claims description 3
- 230000002265 prevention Effects 0.000 claims 1
- 238000010276 construction Methods 0.000 abstract description 25
- 230000005641 tunneling Effects 0.000 abstract description 7
- 238000005516 engineering process Methods 0.000 description 7
- 239000000463 material Substances 0.000 description 4
- 238000005553 drilling Methods 0.000 description 3
- 239000002893 slag Substances 0.000 description 3
- 238000005452 bending Methods 0.000 description 2
- 238000005422 blasting Methods 0.000 description 2
- 229910001294 Reinforcing steel Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 238000010079 rubber tapping Methods 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
- E21D11/006—Lining anchored in the rock
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D11/00—Lining tunnels, galleries or other underground cavities, e.g. large underground chambers; Linings therefor; Making such linings in situ, e.g. by assembling
- E21D11/14—Lining predominantly with metal
- E21D11/18—Arch members ; Network made of arch members ; Ring elements; Polygon elements; Polygon elements inside arches
Landscapes
- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Structural Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Excavating Of Shafts Or Tunnels (AREA)
- Lining And Supports For Tunnels (AREA)
Abstract
The invention relates to a steel arch frame for preventing tunnel collapse of an underground rock crushing section and a supporting method thereof. The method can effectively shorten the tunneling construction period of the collapsed section of the roadway or the surrounding rock crushing section, and timely carry out advanced steel pipe pre-support and steel arch combined support on the collapsed section of the roadway, thereby avoiding the risk of secondary collapse easily caused by insufficient strength when other support methods are used, and ensuring the construction safety.
Description
Technical Field
The invention relates to an underground rock roadway protection device, in particular to a steel arch frame for preventing roadway collapse of an underground rock crushing section and a supporting method thereof.
Background
A fault or a rock crushing section is often touched in the underground roadway construction process, and the roadway is tunneled under the condition that collapse is caused due to untimely roadway support or secondary collapse and the like are caused due to insufficient support strength. Meanwhile, permanent support of the collapsed section and the surrounding rock crushing section is always the key and difficult point of underground roadway construction. The traditional tunnel collapse section construction technology has the following defects: 1. the requirement of the advanced small conduit grouting on the rock mass is high; 2. when the steel arch frame, the net and the system anchor rod are supported, the stable collapse body of the collapse section needs to be disturbed and constructed, the potential safety hazard of excavation is large, secondary collapse is easy to occur, and the safety of site construction operators cannot be guaranteed; 3. the combined supporting technology is adopted, the construction progress of the secondary lining is slow in advance, the cost is high, and the safety is not ensured; 4. the grouting cost, the supporting cost, the delay penalty cost of the construction period and the like of the collapse construction technology are high.
Disclosure of Invention
The invention aims to provide a steel arch frame for preventing the collapse of a tunnel at an underground rock crushing section and a supporting method thereof, wherein the steel arch frame has stable construction quality and high supporting strength, reduces the labor intensity of a construction site, accelerates the progress of engineering, and can effectively solve the problem that the collapse potential safety hazard exists in tunneling.
In order to achieve the purpose, the invention provides a steel arch center for preventing the collapse of a tunnel at an underground rock crushing section, which is characterized in that: the arch truss comprises an advanced steel pipe and a plurality of groups of arch truss bodies, wherein adjacent arch truss bodies are connected through a plurality of connecting and fixing ribs, each arch truss body comprises a left arch truss column leg, a right arch truss column leg and an arch truss arch crown for connecting the left arch truss column leg and the right arch truss column leg, and arch truss column leg supporting plates are arranged at the bottoms of the arch truss column legs; the supporting method comprises the following steps: (1) preparing a plurality of arch frames according to the section of the roadway and the length of the crushed section, splitting and transporting arch frame column legs, arch frame vaults and arch frame column leg supporting plates to a working surface, assembling the arch frames on the working surface on site, wherein the installation distance of the arch frame bodies adopts the distance of 500-1000 mm according to the actual geological excavation and collapse conditions on site; adjacent arch support bodies are welded into an integral steel arch support by adopting connecting and fixing ribs; (2) after the integral steel arch frame forms a support, pre-punching holes at the arch crown and the arch frame column leg side of a working face, embedding advanced steel pipes into the holes to form pre-supports, connecting the pre-supports with the working face to form a protective false roof, arranging the advanced steel pipes in an annular manner, welding the advanced steel pipes and the steel arch frame support into a whole at intervals of 500mm according to the rock crushing degree; (3) after the installation is finished, the thickness of the sprayed concrete with the spraying strength larger than C15 is larger than 150mm through the tissue guniting operation, so that the whole advance steel pipe pre-support and the steel arch support are combined to support to form a whole, and a permanent support is formed.
In the technical scheme of the steel arch frame for preventing the collapse of the tunnel at the underground rock crushing section and the supporting method thereof, the further preferred technical scheme is characterized in that:
1. the arch frame vault is an arc vault;
2. the arch frame column legs, the arch frame vault and the arch frame column leg supporting plates are all formed by processing I-steel.
Compared with the prior art, the invention has the following beneficial effects:
1. the advanced steel pipe pre-support and the steel arch combined support are combined with the sprayed concrete support, so that the support strength is greatly enhanced, the risk that secondary collapse is easily caused due to insufficient strength when other support modes are used is avoided, and the construction safety is ensured;
2. the advanced steel pipe pre-support and steel arch combined support technology is used for temporarily supporting a collapse section and a surrounding rock crushing section, so that the requirements on the conditions of surrounding rock stability, disturbance and the like are low;
3. the advance steel pipe pre-supporting and steel arch combined supporting technology is adopted, so that the tunneling construction period of a tunnel collapse section or a surrounding rock crushing section is shortened, and the overall construction period is shortened. The traditional over-collapse construction technology is used for advanced grouting, slag discharging and supporting, advanced grouting equipment is used, the process is complex, and the cycle time is long; and the construction of supporting by using the steel arch frame is relatively simple and convenient, and the cycle time is shortened.
Drawings
Fig. 1 is a schematic structural diagram of the steel arch of the invention.
Detailed Description
The following will clearly and completely describe the technical solutions 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 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.
A steel arch frame for preventing the collapse of a tunnel at an underground rock crushing section and a supporting method thereof comprise an advance steel pipe 4 and a plurality of groups of arch frame bodies, wherein the adjacent arch frame bodies are connected through a plurality of connecting and fixing ribs, each arch frame body comprises a left arch frame column leg 2, a right arch frame column leg 2 and an arch frame arch crown 3 for connecting the left arch frame column leg and the right arch frame column leg, and arch frame column leg supporting plates 1 are arranged at the bottoms of the arch frame column legs 2; the supporting method comprises the following steps: (1) preparing a plurality of arch frames according to the section of the roadway and the length of the crushed section, splitting and transporting arch frame column legs, arch frame vaults and arch frame column leg supporting plates to a working surface, assembling the arch frames on the working surface on site, wherein the installation distance of the arch frame bodies adopts the distance of 500-1000 mm according to the actual geological excavation and collapse conditions on site; adjacent arch support bodies are welded into an integral steel arch support by adopting connecting and fixing ribs; (2) after the integral steel arch frame forms a support, pre-punching holes at the arch crown and the arch frame column leg side of a working face, embedding advanced steel pipes into the holes to form pre-supports, connecting the pre-supports with the working face to form a protective false roof, arranging the advanced steel pipes in an annular manner, welding the advanced steel pipes and the steel arch frame support into a whole at intervals of 500mm according to the rock crushing degree; (3) after the installation is finished, the thickness of the sprayed concrete with the spraying strength larger than C15 is larger than 150mm through the tissue guniting operation, so that the whole advance steel pipe pre-support and the steel arch support are combined to support to form a whole, and a permanent support is formed. The steel arch frame is formed by processing I-shaped steel I12-I16 on site. And (5) slicing and processing the steel arch frame in sections. The arc vault is formed by one-step bending of a cold bending machine. The thickness delta =10mm is welded at the joint of the steel support end, and a 200 x 200 steel plate drilled bolt hole is connected with the steel support column leg by a phi 16 x 43 bolt. And if necessary, welding the two steel plates between the column legs and the arch part into a whole. The bottom of each column leg is welded with a steel plate with the thickness delta =10mm, the stress area is enlarged by 200 x 200, and a certain distance is ensured between two steel support arc-shaped arches to ensure that the advanced steel pipe can smoothly pass through.
The arch frame vault is an arc vault. The arch frame column legs, the arch frame vault and the arch frame column leg supporting plates are all formed by processing I-shaped steel, the steel arch frame can be optionally adjusted in I12-I16 through I-shaped steel and channel steel, the steel arch frame can be selected according to different conditions of a roadway, in order to ensure that the single steel frame of the steel arch frame does not topple, 500 mm-1000 mm longitudinal connecting ribs are adopted or the steel frame and the steel frame are welded into a whole through profile steel with the same material as the steel support, the steel arch frame distance can be adjusted according to surrounding rock conditions of the roadway, the maximum distance of the steel arch frame is 1000mm, when the roadway collapses and the height is larger than 3m, the supporting distance of the steel arch frame cannot be larger than 500 mm. The method is suitable for the construction of various underground broken section roadways, and can effectively prevent and control underground roadway geological disasters. The method can also be used when the tunnel excavation construction meets the broken surrounding rock section.
The invention relates to a pre-support of an advance steel pipe and a combined support technology of a steel arch, which welds an arch, a bottom beam and an advance steel pipe into a whole to form a complete stress structure. And drilling an advance hole by using a rock drill, inserting an advance steel pipe into the tunneling rock, welding the other end of the advance steel pipe to the steel arch frame, wherein the tunneling length is less than the length of the steel pipe each time, and forming a temporary support after blasting. The advanced steel pipe pre-support and the steel arch frame are jointly supported to form an annular closed stable whole body, so that the falling of slag stones at the collapse-prone section is prevented. The advanced steel pipe pre-support and the steel arch combined support have the arched stress characteristic, and the strong support formed by the steel arch can avoid secondary collapse of the unstable section of the roadway and ensure the construction safety. During tunnel construction, the size of a steel arch frame matched with the section of a tunnel is selected according to the field condition, and the length of an appropriate advanced steel pipe is selected according to the circulation footage and the geological condition. Firstly, processing a proper amount of steel arch frames according to the section of a roadway, supporting two steel arch frames on a tunneling surface, drilling an advance hole on the periphery of a tunnel face, wherein the hole depth is larger than that of a tunneling ruler in each cycle, then inserting one section of advance steel pipe, and welding and fixing the other end of the advance steel pipe on the steel arch frames. And performing rock drilling, blasting and slag tapping according to normal construction steps. After deslagging, anchor rod hanging net temporary support is quickly carried out, then steel arch frames are supported, integrity and supporting force can be enhanced by welding the steel arch frames through reinforcing steel bars, and after the steel arch frames are supported, sprayed concrete (with strength higher than C15) is supported to form permanent support.
According to the steel arch support stress principle, the steel arch adopts an arch structure, so that the stress is uniform, the structure is stable, and the steel arch is not easy to deform; the stand is adopted and is extended the column leg to below the bottom plate to add a bottom supporting beam, can effectively resist the horizontal thrust to the column leg side direction that produces because of the convergence of surrounding rock change, the anchor net spouts can increase the lifting surface area, the dispersion stress point makes adjacent two sets of steel bow member link into a whole, then make all steel bow members link into a whole, reinforcing antidumping nature, the stability of increase structure, advance steel pipe prestretching and steel bow member joint support can avoid broken rock to collapse effectively, play the guard action to constructor in the tunnel, construction progress has been accelerated because of the safety guarantee.
The construction steps of the invention are as follows: 1. and (3) installing a steel arch, wherein the installation distance of the steel supports is 500-1000 mm according to the actual geological excavation and collapse conditions on site, and the installation distance of the steel supports can be reduced according to the actual conditions on site when necessary. The steel support is installed on site, the processed arch centering is transported to a working surface in a split mode, and the processed arch centering is assembled into a whole in a split mode according to design requirements. And (3) inspecting the installation quality of the steel support, mainly inspecting the installation verticality of the steel support, and ensuring that the stress structure meets the design requirement after the steel support is installed. Two steel supports are vertically installed and welded by section steel made of the same material to form an integral steel arch, and a certain distance is ensured between the two steel support arches to ensure that the advanced steel pipe smoothly passes through the integral steel arch. The bolt connection can be realized by screwing the nut by an operator with a common wrench by means of own strength, so that the connected contact surface can be ensured to be closely attached without obvious gaps. In order to ensure that the stress of the bolts in the connecting joint is uniform, the fastening sequence of the bolts is carried out symmetrically; and re-screwing, namely a two-time fastening method, is adopted to ensure that all bolts in the joint can be uniformly stressed. The bolt connection fastening test adopts a hammering method. Namely, a small hammer of 3 kilograms is used, one hand holds the head of the bolt (or the nut), and the other hand is knocked by the hammer, so that the bolt head (the nut) is required not to deviate and shake; the hammer is not loosened and is dry and crisp. Otherwise, the bolt fastening quality is poor, and the bolt needs to be fastened again for construction. The two adjacent steel arches are longitudinally connected by welding profile steels made of the same material, and the circumferential distance is 0.5-0.8 m, so that the stable whole is welded, the condition that a single steel support overturns is prevented, and the construction safety is ensured. 2. And the steel pipe is advanced, the advance support is made of the same material, the arch crown and the side wall of the working face are pre-perforated after being supported by the steel arch frame, and the steel pipe is embedded into the hole to form the pre-support. And is connected with the working surface to form a protective false roof. The advanced steel pipes are annularly arranged, the distance is 500mm according to the rock breaking degree, and the advanced steel pipes and the steel arch support are welded into a whole. The advanced steel pipes are tightly and annularly arranged to form a whole, and the stability of the advanced steel pipes is kept by using the pre-support provided by the steel pipes and the steel arch frame, so that the collapse is prevented, and the safety of a supporting structure is ensured. 3. And (3) performing guniting operation, wherein after the mounting is finished, the thickness of the shotcrete with the guniting strength larger than C15 is larger than 150mm, so that the whole advanced steel pipe pre-support and the steel arch combined support form a whole, the strength and the stability of the support are enhanced, and the permanent support is formed.
The above description is only for the preferred embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can substitute or change the technical solution of the present invention and the inventive concept thereof within the scope of the present invention.
Claims (3)
1. The utility model provides a steel bow member of prevention underground rock crushing section tunnel collapse which characterized in that: the arch truss comprises an advanced steel pipe and a plurality of groups of arch truss bodies, wherein adjacent arch truss bodies are connected through a plurality of connecting and fixing ribs, each arch truss body comprises a left arch truss column leg, a right arch truss column leg and an arch truss arch crown for connecting the left arch truss column leg and the right arch truss column leg, and arch truss column leg supporting plates are arranged at the bottoms of the arch truss column legs;
the supporting method comprises the following steps:
(1) preparing a plurality of arch frames according to the section of the roadway and the length of the crushed section, splitting and transporting arch frame column legs, arch frame vaults and arch frame column leg supporting plates to a working surface, assembling the arch frames on the working surface on site, wherein the installation distance of the arch frame bodies adopts the distance of 500-1000 mm according to the actual geological excavation and collapse conditions on site; adjacent arch support bodies are welded into an integral steel arch support by adopting connecting and fixing ribs;
(2) after the integral steel arch frame forms a support, pre-punching holes at the arch crown and the arch frame column leg side of a working face, embedding advanced steel pipes into the holes to form pre-supports, connecting the pre-supports with the working face to form a protective false roof, arranging the advanced steel pipes in an annular manner, welding the advanced steel pipes and the steel arch frame support into a whole at intervals of 500mm according to the rock crushing degree;
(3) after the installation is finished, the thickness of the sprayed concrete with the spraying strength larger than C15 is larger than 150mm through the tissue guniting operation, so that the whole advance steel pipe pre-support and the steel arch support are combined to support to form a whole, and a permanent support is formed.
2. The steel arch centering and the supporting method thereof for preventing the collapse of the roadway at the underground rock crushing section according to the claim 1, wherein: the arch frame vault is an arc vault.
3. The steel arch centering and the supporting method thereof for preventing the collapse of the roadway at the underground rock crushing section according to the claim 1, wherein: the arch frame column legs, the arch frame vault and the arch frame column leg supporting plates are all formed by processing I-steel.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011246647.4A CN112502730A (en) | 2020-11-10 | 2020-11-10 | Steel arch frame for preventing collapse of roadway at underground rock crushing section and supporting method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011246647.4A CN112502730A (en) | 2020-11-10 | 2020-11-10 | Steel arch frame for preventing collapse of roadway at underground rock crushing section and supporting method thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112502730A true CN112502730A (en) | 2021-03-16 |
Family
ID=74957450
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202011246647.4A Pending CN112502730A (en) | 2020-11-10 | 2020-11-10 | Steel arch frame for preventing collapse of roadway at underground rock crushing section and supporting method thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112502730A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114046157A (en) * | 2022-01-12 | 2022-02-15 | 北京科技大学 | Large-span false roof structure adopting downward horizontal access filling method and construction method |
| CN116575945A (en) * | 2023-07-14 | 2023-08-11 | 长春黄金研究院有限公司 | High-strength yielding support structure for underground mine support and use method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103016027A (en) * | 2013-01-21 | 2013-04-03 | 中南大学 | Tunnel or roadway excavating method under weak and broken complicated geological conditions |
| CN104989434A (en) * | 2015-07-17 | 2015-10-21 | 山东科技大学 | Method for treating landslide of tunneling working face with pipe penetration combined lagging jacks |
| CN108005675A (en) * | 2017-11-16 | 2018-05-08 | 中国电建集团昆明勘测设计研究院有限公司 | Dynamic superposition coupling supporting method and supporting structure for fault fracture zone roadway |
| CN211549726U (en) * | 2019-11-05 | 2020-09-22 | 中十冶集团城建工程有限公司 | Three-core arch steel arch frame combined supporting system |
| CN211851855U (en) * | 2020-01-17 | 2020-11-03 | 河北钢铁集团矿业有限公司 | Roadway supporting structure through argillaceous broken zone |
-
2020
- 2020-11-10 CN CN202011246647.4A patent/CN112502730A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103016027A (en) * | 2013-01-21 | 2013-04-03 | 中南大学 | Tunnel or roadway excavating method under weak and broken complicated geological conditions |
| CN104989434A (en) * | 2015-07-17 | 2015-10-21 | 山东科技大学 | Method for treating landslide of tunneling working face with pipe penetration combined lagging jacks |
| CN108005675A (en) * | 2017-11-16 | 2018-05-08 | 中国电建集团昆明勘测设计研究院有限公司 | Dynamic superposition coupling supporting method and supporting structure for fault fracture zone roadway |
| CN211549726U (en) * | 2019-11-05 | 2020-09-22 | 中十冶集团城建工程有限公司 | Three-core arch steel arch frame combined supporting system |
| CN211851855U (en) * | 2020-01-17 | 2020-11-03 | 河北钢铁集团矿业有限公司 | Roadway supporting structure through argillaceous broken zone |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114046157A (en) * | 2022-01-12 | 2022-02-15 | 北京科技大学 | Large-span false roof structure adopting downward horizontal access filling method and construction method |
| CN116575945A (en) * | 2023-07-14 | 2023-08-11 | 长春黄金研究院有限公司 | High-strength yielding support structure for underground mine support and use method thereof |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN109209392B (en) | Full-ring excavation method suitable for IV-V-grade surrounding rock of large-section tunnel | |
| CN110409461A (en) | A kind of base pit stand construction based on assembled large-diameter tubular pile | |
| CN102140924B (en) | Double-shell coupling supporting method of deep soft rock tunnel | |
| CN108868834B (en) | Temporary support device for tunnel arch wall primary support intrusion limit arch changing construction | |
| CN110904867B (en) | Construction method for dismantling upper-span existing line arch bridge | |
| CN112502730A (en) | Steel arch frame for preventing collapse of roadway at underground rock crushing section and supporting method thereof | |
| CN102305091B (en) | Support structure for hard rock large-section tunnel construction, and construction method for support structure | |
| CN110566236B (en) | Combined supporting device and supporting method for pipe shed and steel support | |
| CN206707726U (en) | A kind of gob side entry retaining roadside support system | |
| CN113944479B (en) | Poor geological tunnel three-fork construction method | |
| CN112727470B (en) | Construction reinforcing method for shield tunnel at overlapped section | |
| CN210829267U (en) | Shield constructs interval back construction air shaft structure | |
| CN210622819U (en) | Pipe shed and steel support combined supporting device | |
| KR100505301B1 (en) | The structure for underground tunnel formation | |
| CN116464453A (en) | Construction method for quick turning of hard rock tunnel through one-time roof picking | |
| CN113982639B (en) | Tunnel lining full-ring dismantling and replacing construction method in unfavorable geological region | |
| CN111946351B (en) | Rapid excavation method for contact channel of hard rock stratum of rail transit | |
| CN114109416A (en) | Method for replacing TBM main bearing in tunnel | |
| CN211498542U (en) | Static crushing and dismantling construction structure of upper-span existing line arch bridge | |
| CN111236961B (en) | Construction method of expandable mudstone orthogonal inclined shaft detachable portal frame | |
| CN210622821U (en) | Bias tunnel bow member and bias tunnel bow member top-raising structure | |
| CN210195776U (en) | Drill rod retention steel frame supporting mechanism in easy-collapse area | |
| CN114135315A (en) | Advanced stress release construction method for severe large-deformation tunnel | |
| CN221546976U (en) | Broken rock mass tunnel cover encircles supporting construction | |
| CN110714765A (en) | Construction method for post-construction air shaft of shield interval |
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 | ||
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210316 |