CN111365036A - I-steel-corrugated steel (GB) combined supporting structure for soft rock large-deformation tunnel - Google Patents
I-steel-corrugated steel (GB) combined supporting structure for soft rock large-deformation tunnel Download PDFInfo
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- CN111365036A CN111365036A CN202010263303.8A CN202010263303A CN111365036A CN 111365036 A CN111365036 A CN 111365036A CN 202010263303 A CN202010263303 A CN 202010263303A CN 111365036 A CN111365036 A CN 111365036A
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- corrugated steel
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- soft rock
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 78
- 239000010959 steel Substances 0.000 title claims abstract description 78
- 239000011435 rock Substances 0.000 title claims abstract description 43
- 239000011381 foam concrete Substances 0.000 claims abstract description 10
- 238000010276 construction Methods 0.000 claims abstract description 8
- 239000011378 shotcrete Substances 0.000 claims abstract description 6
- 238000009412 basement excavation Methods 0.000 claims abstract description 5
- 239000011150 reinforced concrete Substances 0.000 claims abstract description 4
- 239000004567 concrete Substances 0.000 claims description 11
- 238000005507 spraying Methods 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 2
- 238000005553 drilling Methods 0.000 claims 2
- 238000009434 installation Methods 0.000 claims 1
- 201000010099 disease Diseases 0.000 abstract description 5
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 abstract description 5
- 238000000034 method Methods 0.000 abstract description 4
- 238000005336 cracking Methods 0.000 abstract description 3
- 230000007547 defect Effects 0.000 abstract description 3
- 230000000694 effects Effects 0.000 abstract description 3
- 238000010521 absorption reaction Methods 0.000 abstract 1
- 230000009545 invasion Effects 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 27
- 238000001125 extrusion Methods 0.000 description 4
- 230000009172 bursting Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 1
- 241000576429 Forsythia suspensa Species 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000009365 direct transmission Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000011241 protective layer Substances 0.000 description 1
- 239000010454 slate Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
Images
Classifications
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- 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
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- 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
- E21D11/04—Lining with building materials
- E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
- E21D11/102—Removable shuttering; Bearing or supporting devices therefor
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- 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
- E21D11/04—Lining with building materials
- E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
- E21D11/105—Transport or application of concrete specially adapted for the lining of tunnels or galleries ; Backfilling the space between main building element and the surrounding rock, e.g. with concrete
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- 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
- E21D11/04—Lining with building materials
- E21D11/10—Lining with building materials with concrete cast in situ; Shuttering also lost shutterings, e.g. made of blocks, of metal plates or other equipment adapted therefor
- E21D11/107—Reinforcing elements therefor; Holders for the reinforcing elements
-
- 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
- E21D11/38—Waterproofing; Heat insulating; Soundproofing; Electric insulating
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D21/00—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection
- E21D21/0026—Anchoring-bolts for roof, floor in galleries or longwall working, or shaft-lining protection characterised by constructional features of the bolts
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Structural Engineering (AREA)
- Architecture (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Civil Engineering (AREA)
- Lining And Supports For Tunnels (AREA)
Abstract
The invention relates to the technical field of underground engineering, and discloses an I-shaped steel-corrugated steel (GB) combined supporting structure of a soft rock large-deformation tunnel, which comprises I-shaped steel, corrugated steel, a foam concrete layer, two lining reinforced concrete layers, an anchor rod and a waterproof plate. The corrugated steel is prefabricated into pieces, assembled on site, the pieces and the pieces are in annular lap joint to form an arch, the pieces and the pieces are radially arranged along the inner contour of tunnel excavation, and I-shaped steel is erected on the inner side of the corrugated steel every 0.9-2.4 m. The corrugated steel is closely attached to the surrounding rock and is backfilled by sprayed concrete. The invention greatly improves the supporting capability of the primary lining of the tunnel, greatly prevents soft rock collapse, forms a supporting system and plays a good role in preventing and treating diseases which are easy to occur due to soft rock deformation. Compared with the traditional primary tunnel support, the invention has the advantages of reduced thickness, increased strength, stronger toughness, simplified process, shortened operation time, reduced safety risk and reduced construction cost. In addition, the foam concrete buffer layer has a strong energy absorption effect, and the defects of deformation, limit invasion, cracking and the like of the secondary lining are effectively prevented.
Description
Technical Field
The invention relates to the technical field of underground engineering, in particular to a I-shaped steel-corrugated steel (GB) combined supporting structure of a soft rock large-deformation tunnel.
Background
With the urgent need and rapid development of the infrastructure of China, the quantity, scale and speed of the engineering construction of roads, bridges, tunnels, municipal works and the like are all at the leading level in the world. Particularly, in the areas where the southwest part of China is vigorously developing traffic facilities, the road-bridge tunnel height is as high as 60-80%, and the construction of weak surrounding rock tunnels becomes a serious difficulty and bottleneck for road construction.
The soft rock large-deformation tunnel is a common geological disaster in the tunnel construction process, the lithology of the tunnel mainly comprises sandstone, slate, phyllite, carbon phyllite and the like, the rock is extremely low in strength, extremely poor in integrity and has certain expansibility, creep deformation is easy to occur under the influence of ground stress after excavation, and once the support is not timely, the rock is easy to disintegrate and collapse. The large deformation of the soft rock has the characteristics of high deformation speed, large deformation, wide influence range, long duration, deep surrounding rock damage range and the like, so that the large deformation of the soft rock becomes a world-level problem which puzzles the construction and operation of tunnels.
According to the analysis of the large deformation mechanism of the soft rock, the expansive soft rock, the high-stress soft rock, the jointed soft rock and the composite soft rock have the mechanical characteristics of plasticity, expansibility, disintegrability, rheological property and the like. The current commonly used support mode is a deep and long anchor bolt spray anchor support, i-steel (grid arch) primary support + secondary lining concrete or two-layer i-steel primary support + two-layer secondary lining concrete, the traditional support modes of the forced hard top do not fully consider the characteristics of strong rheological property, large structural stress, high deformation rate, large extrusion deformation and the like of the large deformation of soft rock, and the following problems often occur in the implementation process:
(1) the primary support of the steel-gram steel is difficult to resist the large extrusion deformation of surrounding rocks, and the diseases such as distortion, breakage, fracture and the like of the I-steel often occur;
(2) the I-shaped steel and the I-shaped steel are supported by sprayed concrete, and soft rock is easy to gush from a weak place of the sprayed concrete in a rheological state to form the defects of mud bursting, water bursting and the like;
(3) because the primary support is difficult to bear the extrusion damage of large deformation of soft rock, the secondary lining concrete is implemented after the surrounding rock is not converged and deformed stably, and the secondary lining concrete is easy to form diseases such as cracking, deformation, water leakage and the like.
Disclosure of Invention
The invention aims to provide a H-shaped steel-corrugated steel (GB) combined supporting structure of a soft rock large-deformation tunnel, which realizes 'soft-gram-steel' of the large deformation of soft rock by primary support through a rigid (H-shaped steel) and flexible (corrugated steel) combined supporting system, and effectively restrains the flow deformation and the extrusion large deformation of soft rock; meanwhile, a yielding support system is formed by arranging a buffer layer between the primary support and the two linings, so that the defects that the two linings crack, deform, invade limit and the like caused by direct transmission of load to the two linings are effectively prevented, and the safety of the tunnel support mechanism is greatly improved.
In order to achieve the purpose, the invention adopts the following technical scheme:
a I-steel-corrugated steel (GB) combined supporting structure for a soft rock large-deformation tunnel comprises the following three structural layers:
(1) primary support of a first-layer structure: the tunnel is characterized by being formed by combining I-shaped steel and corrugated steel, wherein the I-shaped steel and the corrugated steel are arranged along the inner contour line of tunnel excavation, the corrugated steel is arranged between I-shaped steel trusses, the I-shaped steel and the corrugated steel are both closely attached to surrounding rocks, and the wave trough positions of the corrugated steel are backfilled and compacted by sprayed concrete.
(2) Second layer structure buffer layer: the first layer of primary support layer is arranged on the inner side of the first layer of primary support layer, and wraps the inner sides of the I-shaped steel and the corrugated steel to form a yielding support system.
(3) The second lining layer of the third layer structure: the second buffer layer is arranged below the first buffer layer and is formed by pouring through a template lining trolley.
Furthermore, the I-shaped steel type in the structural layer is 20-25, the I-shaped steel interval is 1.2-2.4 m, the corrugated steel is processed by adopting a Q345 plate, the wavelength-wave crest-plate thickness is 300-5 or 380-5, a web plate of the corrugated steel is overlapped on the top of the I-shaped steel to form an integral structure with the I-shaped steel, and the I-shaped steel is arranged on the inner side of the web plate of the corrugated steel to form a rib beam.
Furthermore, radial anchor rods are arranged at the top of the protective arch in the supporting layer at the initial stage of the structure, and foot locking anchor rods are arranged at the arch foot and arch bottom positions.
Furthermore, I-shaped steel and corrugated steel in the structural buffer layer are arranged in a staggered and occluded mode, foam concrete of the buffer layer is formed by spraying or molding, and the I-shaped steel protective layer is ensured to be more than 2 cm.
Furthermore, a waterproof plate is laid between the buffer layer and the secondary lining layer, and the waterproof plate is closely attached to the inner side of the buffer layer.
Furthermore, double-layer steel bars are laid on the secondary lining layer reinforced concrete, and the thickness of the concrete is 35-50 cm.
In summary, compared with the prior art, the invention has the following beneficial effects:
(1) the I-steel and corrugated steel (GB) combination is adopted in the supporting structure, the I-steel has strong rigidity, the corrugated steel has strong toughness, the I-steel can form rigid restraint on soft rock at the initial stage of large deformation of the soft rock, the toughness of the corrugated steel can be fully utilized to form a yielding device along with the increase of the deformation amount, the deformation of the soft rock is effectively restricted, a supporting system of firstly rigid and then flexible and then rigid is realized, and 'strong support and hard top' is avoided. The support capability of the primary support is greatly improved, and a good support effect is achieved for preventing soft rock collapse;
(2) after corrugated steel is adopted for overlapping among the longitudinal I-shaped steel trusses in the supporting structure, a supporting system similar to a golden bell jar can be formed, the problem that the traditional supporting structure is easy to cause mud-bursting and water-bursting between the I-shaped steel and the I-shaped steel is avoided, and particularly, the supporting structure has a good prevention and treatment effect on piping diseases which are easy to cause joint type soft rock deformation;
(3) compared with the traditional primary support, the primary support structure of the first layer in the support structure has the advantages of reduced thickness, increased strength, stronger toughness, full play of the strength of the support material, simplified working procedures, reduced quantity of sprayed concrete, greatly shortened primary support operation time and reduced primary support manufacturing cost;
(4) the foam concrete buffer layer is arranged in the middle of the supporting structure, so that the supporting structure has strong capacity of absorbing soft rock and primary supporting deformation, reduces the deformation pressure of the secondary lining concrete, enables the stress of the secondary lining to be uniformly distributed, and effectively prevents the secondary lining from deforming, invading limit, cracking and other diseases.
Drawings
FIG. 1 is a three-dimensional schematic diagram of a combined supporting structure of I-steel and corrugated steel (GB)
FIG. 2 is a typical cross-sectional schematic diagram of a joist steel-corrugated steel (GB) combined supporting structure
FIG. 3 is a schematic longitudinal sectional view of a combined supporting structure of I-steel and corrugated steel (GB)
Fig. 4 is a large drawing of a first layer of an I-steel-corrugated steel (GB) combined supporting structure.
Claims (4)
1. The utility model provides a big deformation tunnel I-steel-corrugated steel (GB) combination supporting construction of soft rock which characterized in that includes following three layer construction:
(1) i-steel-corrugated steel (GB) combination primary support structural layer, its characterized in that: the anchor rod comprises corrugated steel 10, I-steel 9, sprayed concrete 8, a radial anchor rod 4 and a foot locking anchor rod 5;
(2) the foam concrete buffer structure layer is characterized in that: comprises a foam concrete buffer layer 2 and a waterproof board 12;
(3) secondary lining concrete structure layer, its characterized in that: comprising two liners of reinforced concrete 3.
2. The I-steel-corrugated steel (GB) combined supporting structure for the soft rock large-deformation tunnel according to claim 1, wherein the GB combined supporting structure comprises: firstly, excavating an upper half step of a tunnel, controlling the excavation depth to be about 60-76 cm every cycle, after excavation, timely primarily spraying concrete 7 to seal surrounding rocks, then annularly installing corrugated steel 10, enabling each piece of corrugated steel 10 to be 60-76 cm wide and 3.2-3.6 m long, solidifying the corrugated steel by using a connecting bolt 11 in an annular lap joint mode, reserving grouting holes or spraying holes in a corrugated steel web plate, and grouting from the grouting holes or spraying concrete 8 and the surrounding rocks 6 to backfill tightly after installation; after two cycles are carried out, I-shaped steel 9 is arranged on the inner side of the corrugated steel to form a rib beam, the I-shaped steel 9 is as close as possible to the surrounding rock 6, and the lap joint width of the I-shaped steel and the corrugated steel is 2-3 cm; after the I-shaped steel 9 and the corrugated steel 10 are implemented, two radial anchor rods 4 are arranged on the arch crown in a drilling mode, two foot-locking anchor rods 5 are arranged on two sides of the arch foot in a drilling mode respectively, and the lengths of the radial anchor rods and the foot-locking anchor rods are set to be 3.5-6 m according to the surrounding rock conditions; after the upper half section is implemented, excavating a lower half section and an inverted arch, wherein the implementing sequence of the lower half section and the inverted arch support is consistent with that of the upper half section; and forming a complete primary support structure layer after the supports are closed into a ring.
3. The I-shaped steel-corrugated steel (GB) combined supporting structure for the soft rock large-deformation tunnel according to claim 1, wherein the foam concrete buffer structure layer (2) with the second layer structure is made of foam concrete and is formed by pouring through mould building, the compressibility of the foam concrete is 55% -70%, the thickness of the foam concrete is 7-25 cm, and the yielding supporting resistance is 1.5-2.0 MP; the implementation can be implemented after the upper half-section support is formed, and the lower half-section can be implemented after the side wall support is formed.
4. The I-shaped steel-corrugated steel (GB) combined supporting structure for the soft rock large-deformation tunnel according to claim 1, wherein a waterproof plate 12 is laid along the inner side of the buffer layer 2 before the secondary lining structure layer 3 is implemented on a third-layer structure secondary lining structure layer 3, the waterproof plate 12 is laid to be as close to the buffer layer 2 as possible, the secondary lining structure layer 3 is made of reinforced concrete materials, double layers of steel bars are laid, the concrete is waterproof concrete, the seepage-proofing grade must reach P12, the strength is C30, the thickness is 35-50 cm, and the structure is formed by one-step pouring through a lining trolley.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010263303.8A CN111365036A (en) | 2020-04-07 | 2020-04-07 | I-steel-corrugated steel (GB) combined supporting structure for soft rock large-deformation tunnel |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010263303.8A CN111365036A (en) | 2020-04-07 | 2020-04-07 | I-steel-corrugated steel (GB) combined supporting structure for soft rock large-deformation tunnel |
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| Publication Number | Publication Date |
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| CN111365036A true CN111365036A (en) | 2020-07-03 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010263303.8A Pending CN111365036A (en) | 2020-04-07 | 2020-04-07 | I-steel-corrugated steel (GB) combined supporting structure for soft rock large-deformation tunnel |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111963213A (en) * | 2020-07-13 | 2020-11-20 | 北京鸿锐嘉科技发展有限公司 | Tunnel corrugated steel plate reinforcing device and method |
| CN116291603A (en) * | 2023-03-10 | 2023-06-23 | 云南省交通规划设计研究院有限公司 | Retractable corrugated plate structure suitable for soft rock tunnel and design method |
| CN116378677A (en) * | 2023-05-29 | 2023-07-04 | 湖南省交通规划勘察设计院有限公司 | Tunnel construction method and tunnel structure of full-span filling karst cave section |
-
2020
- 2020-04-07 CN CN202010263303.8A patent/CN111365036A/en active Pending
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111963213A (en) * | 2020-07-13 | 2020-11-20 | 北京鸿锐嘉科技发展有限公司 | Tunnel corrugated steel plate reinforcing device and method |
| CN111963213B (en) * | 2020-07-13 | 2022-12-20 | 北京鸿锐嘉科技发展有限公司 | Tunnel corrugated steel plate reinforcing device and method |
| CN116291603A (en) * | 2023-03-10 | 2023-06-23 | 云南省交通规划设计研究院有限公司 | Retractable corrugated plate structure suitable for soft rock tunnel and design method |
| CN116291603B (en) * | 2023-03-10 | 2023-11-28 | 云南省交通规划设计研究院有限公司 | Retractable corrugated plate structure suitable for soft rock tunnel and design method |
| CN116378677A (en) * | 2023-05-29 | 2023-07-04 | 湖南省交通规划勘察设计院有限公司 | Tunnel construction method and tunnel structure of full-span filling karst cave section |
| CN116378677B (en) * | 2023-05-29 | 2023-08-29 | 湖南省交通规划勘察设计院有限公司 | Tunnel construction method and tunnel structure of full-span filling karst cave section |
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Application publication date: 20200703 |
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