CN108625882A - A kind of deformed bar skeleton spray concrete arch rib supporting construction and construction method - Google Patents
A kind of deformed bar skeleton spray concrete arch rib supporting construction and construction method Download PDFInfo
- Publication number
- CN108625882A CN108625882A CN201810748009.9A CN201810748009A CN108625882A CN 108625882 A CN108625882 A CN 108625882A CN 201810748009 A CN201810748009 A CN 201810748009A CN 108625882 A CN108625882 A CN 108625882A
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- China
- Prior art keywords
- deformed bar
- supporting construction
- concrete
- bar skeleton
- arch rib
- 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
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- 239000004567 concrete Substances 0.000 title claims abstract description 41
- 238000010276 construction Methods 0.000 title claims abstract description 37
- 239000007921 spray Substances 0.000 title claims abstract description 32
- 230000008093 supporting effect Effects 0.000 title claims abstract description 28
- 230000002787 reinforcement Effects 0.000 claims abstract description 33
- 239000011435 rock Substances 0.000 claims abstract description 25
- 210000003205 muscle Anatomy 0.000 claims abstract description 22
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 20
- 239000010959 steel Substances 0.000 claims abstract description 20
- 239000004568 cement Substances 0.000 claims abstract description 6
- 230000003014 reinforcing effect Effects 0.000 claims description 20
- 238000002347 injection Methods 0.000 claims description 4
- 239000007924 injection Substances 0.000 claims description 4
- 239000000835 fiber Substances 0.000 claims description 3
- 231100000241 scar Toxicity 0.000 claims description 3
- 238000009826 distribution Methods 0.000 abstract description 6
- 239000000463 material Substances 0.000 abstract description 6
- 238000010008 shearing Methods 0.000 abstract description 4
- 238000005507 spraying Methods 0.000 abstract description 2
- 238000009412 basement excavation Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000011378 shotcrete Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 235000013399 edible fruits Nutrition 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
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
- E21D11/04—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
-
- 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
- E21D11/15—Plate linings; Laggings, i.e. linings designed for holding back formation material or for transmitting the load to main supporting members
Landscapes
- Engineering & Computer Science (AREA)
- Structural Engineering (AREA)
- Mining & Mineral Resources (AREA)
- Architecture (AREA)
- Civil Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Lining And Supports For Tunnels (AREA)
Abstract
The invention discloses a kind of deformed bar skeleton spray concrete arch rib supporting construction and construction methods.The structure includes deformed bar skeleton and spray concrete.The skeleton is made of circumferential reinforcement and stirrup.The circumferential reinforcement includes conventional ring muscle and Z-shaped connector；According to supporting construction tensile stress distribution characteristics, the conventional ring muscle is laid in vault and country rock side at free face side at arch springing, haunch, and pass through stirrup banding fixed；The Z-shaped connector with it is vertical to angle ± 30 ° with ± 75 ° at connect with the conventional ring muscle by sleeve.The spray concrete is injected on country rock and framework of steel reinforcement.The construction method：1. making framework of steel reinforcement component；2. just spraying concrete toward country rock；3. laying deformed bar skeleton on spray concrete；4. jetting cement covers framework of steel reinforcement.The present invention is based on rib structure loading characteristic, construction and deformed bar skeleton is laid, improve supporting construction stress state, has many advantages, such as that shearing resistance limit splits that ability is strong, durability is good, material property performance is abundant.
Description
Technical field
The present invention relates to weak surrounding rock support technology fields, spray concrete arch rib supporting more particularly to a kind of deformed bar skeleton
Structure and construction method.
Background technology
Weak surrounding rock self-stable ability is poor, and excavation disturbance often causes tunnel surrounding large deformation occur, or even induces surrounding rock failure
Unstability jeopardizes safety for tunnel engineering and operation security, and claim for eot, construction investment is caused to sharply increase.To improve weak surrounding rock
The stability in tunnel, the supporting measure of invention economical rationality are simultaneously reinforced applied to weak surrounding rock, are always the heat of underground engineering circle
Point problem.
Currently, the supporting construction for being related to Support System in Soft Rock Tunnels mainly has following a few classes.1. combined bolting and shotcrete.It is laid in rock mass
Anchor pole, to excavation face jetting cement, spray concrete fits closely country rock surface and provides support, jetting cement and anchor pole in time to be formed altogether with country rock
Same supporting body, but combined bolting and shotcrete does not adapt to and limits country rock large deformation because rigidity is smaller.2. section-steel support.It is disconnected according to country rock
Face shape makes Steel section member, reinforces country rock with whole Pin installations or rod piece erection method, often forms composite supporting construction with spray concrete,
The rigidity of structure and intensity are larger, but require height to excavating section configuration.3. reinforcing bar sprays concrete arch rib.Reinforcing bar is laid on country rock surface
Then skeleton sprays concrete and covers to form arch rib, construction is convenient, has good adaptability to excavating section configuration, is a kind of reinforcing effect
The good weak surrounding rock ruggedized construction of fruit, but the full face framework of steel reinforcement form of the supporting construction is consistent and is laid in spray concrete identical bits
It sets, does not account for rib structure tensile stress distribution characteristics, compression-side reinforcing bar is caused to fail to play examining tensile behavior, arch rib crown and arch
Foot's position spray concrete easily cracks, and seriously affects supporting effect and structure durability.
Invention content
For Support System in Soft Rock Tunnels supporting construction, the present invention is based on arch rib supporting construction tensile stresses point
Cloth feature, construction and lays deformed bar skeleton, improves supporting construction stress state, it is proposed that a kind of shearing resistance limit splits ability
By force, durability is good, material property plays sufficient deformed bar skeleton spray concrete arch rib supporting construction and construction method.
To achieve the above object, the technical solution adopted in the present invention is：
A kind of deformed bar skeleton spray concrete arch rib supporting construction, the structure include deformed bar skeleton and spray concrete.The reinforcing bar
Skeleton is made of circumferential reinforcement and stirrup.The circumferential reinforcement includes conventional ring muscle and Z-shaped connector；It is drawn according to supporting construction
The conventional ring muscle is laid in vault and country rock side at free face side at arch springing, haunch, and passes through stirrup by stress distribution feature
Banding fixed；The Z-shaped connector is passing through sleeve and the conventional ring muscle company with vertical to angle ± 30 ° and ± 75 ° of places
It connects.The spray concrete is injected on country rock and framework of steel reinforcement.
Further, the circumferential reinforcement includes at least two in same rib structure.So that structure is more stablized.
Further, the reinforcing bar of different-diameter can be used in the conventional ring muscle at vault, haunch and arch springing, and diameter is desirable
12~32mm.The reinforcing bar that diameter differs can be used according to stress characteristic, material property is made to give full play to.
Further, the Z-shaped connector is one section of Z-shaped reinforcing bar, is divided into three sections, the folder of both ends part and interlude
Angle is 135 °, and the length of both ends part takes 10d or so, intermediate segment length to take 1.414 (dh- 70), the diameter d of Z-shaped reinforcing bar
Take 16 ~ 20mm, arch rib overall thickness dhTake 300 ~ 700mm.Improve structure shear resistance.
Further, the sleeve is using both sides screw hole deformed bar sleeve not of uniform size.Meet left and right sides reinforcing bar
The requirement that skeleton component diameter may differ.
Further, the minimum stirrup ratio of the stirrup need to be more than or equal to 0.15%.
Further, the spray concrete uses steel fibre concrete, and 1000 ~ 2000mm of width, overall thickness is arch rib thickness, has been needed
All standing framework of steel reinforcement, and cover to reinforcement reaches 35mm.Structure fast erosion is avoided, durability is improved.
Further, the construction method includes the following steps：1. making the normal of various pieces according to actual engineering design
Advise ring muscle, Z-shaped connector and sleeve；2. preparing concrete and to the flushed scar injection at least 35mm thickness in high pressure geomantic omen, so
Afterwards vault with it is vertical at the range of angle ± 30 ° and arch springing with 0 ~ 15 ° of horizontal direction angle within the scope of be sprayed onto again it is few
200mm is thick；3. scene laying circumferential reinforcement, and with stirrup firm welding；4. jetting cement is until being completely covered framework of steel reinforcement and expiring
Sufficient cover to reinforcement reaches 35mm.
Compared with the prior art, beneficial effects of the present invention are embodied in：
1, it is strong to split ability for shearing resistance limit.On the one hand, according to arch rib supporting construction at vault and the arch springing free face side, country rock at haunch
Conventional ring muscle is laid in structure tension position and enhances arch rib and limit and splits ability by the characteristics of side tension.On the other hand, connection is conventional
The Z-shaped connector of ring muscle plays the role of bent-up bar, enhances arch rib shear resistance.
2, durability is good.On the one hand, by constructing and lay deformed bar skeleton, increasing framework of steel reinforcement and spraying the knot of concrete
It closes, enhances arch rib shearing resistance limit and split ability, improve inside configuration stress distribution, bearing capacity is more preferable.On the other hand, concrete
Face is less prone to crack, reduces air and moisture into inside configuration, slows down the corrosion failure of framework of steel reinforcement.
3, material property plays abundant.On the one hand, it conventional ring muscle is laid in arch rib tension side has given full play to reinforcing bar and resist
Performance is drawn, waste of material of the reinforcing bar when compression-side is arranged is avoided.It on the other hand, can be according to arch rib different parts tensile stress
Characteristic distributions select the reinforcing bar of respective diameters or intensity as skeleton, ensure that bar material performance makes full use of.
Description of the drawings
Fig. 1 is the cross section structure schematic diagram of the present invention.
Fig. 2 is the close-up schematic view of the present invention.
Fig. 3 is the A-A cross-sectional views of the present invention.
Fig. 4 is the B-B cross-sectional views of the present invention.
1-conventional ring muscle, 2-Z-shaped connectors, 3-sleeves, 4-stirrups, 5-spray concretes in the figure.
Specific implementation mode
The present invention will be further described below in conjunction with the accompanying drawings.
Embodiment 1
A kind of deformed bar skeleton spray concrete arch rib supporting construction, the structure include deformed bar skeleton and spray concrete 5.The reinforcing bar
Skeleton is made of circumferential reinforcement and stirrup 4.The circumferential reinforcement is divided into conventional ring muscle 1 and Z-shaped connector 2；According to supporting knot
The conventional ring muscle 1 is laid in vault and country rock side at free face side at arch springing, haunch, and led to by structure tensile stress distribution characteristics
Cross 4 banding fixed of stirrup；The Z-shaped connector 2 with it is vertical to angle ± 30 ° with ± 75 ° at connect by sleeve 3 and institute
Conventional ring muscle 1 is stated to connect.The spray concrete 5 is injected on country rock and framework of steel reinforcement.
Further, the circumferential reinforcement includes at least two in same rib structure.
Further, the reinforcing bar of different-diameter can be used in the conventional ring muscle 1 at vault, haunch and arch springing, and diameter can
Take 12 ~ 32mm.
Further, the Z-shaped connector 2 is one section of Z-shaped reinforcing bar, is divided into three sections, both ends part and interlude
Angle is 135 °, and the length of both ends part takes 10d or so, intermediate segment length to take 1.414 (dh- 70), the diameter of Z-shaped reinforcing bar
D takes 16 ~ 20mm, arch rib overall thickness dhTake 300 ~ 700mm.
Further, the sleeve 3 is using both sides screw hole deformed bar sleeve not of uniform size.
Further, the minimum stirrup ratio of the stirrup 4 need to be more than or equal to 0.15%.
Further, the spray concrete 5 uses steel fibre concrete, and 1000 ~ 2000mm of width, overall thickness is arch rib thickness, needs
Framework of steel reinforcement is completely covered, and cover to reinforcement reaches 35mm.
Embodiment 2
The present invention provides the construction methods that a kind of deformed bar skeleton sprays concrete arch rib supporting construction.It is as follows：1. root
Conventional ring muscle 1, Z-shaped connector 2 and the sleeve 3 of various pieces are made according to actual engineering design；2. preparing concrete and to high pressure
The flushed scar injection at least 35mm in geomantic omen is thick, then vault with it is vertical at the range of angle ± 30 ° and arch springing with
It is thick that few 200mm is sprayed onto within the scope of 0 ~ 15 ° of horizontal direction angle again；3. scene laying circumferential reinforcement, and with 4 firm welding of stirrup；④
Jetting cement reaches 35mm up to framework of steel reinforcement is completely covered and meets cover to reinforcement.
Part that the present invention does not relate to is the same as those in the prior art or can be realized by using the prior art.
Claims (6)
1. a kind of deformed bar skeleton sprays concrete arch rib supporting construction, which is characterized in that the structure include deformed bar skeleton and
Spray concrete；The framework of steel reinforcement is made of circumferential reinforcement and stirrup；The circumferential reinforcement includes conventional ring muscle and Z-shaped connector；
The routine ring muscle is laid in free face side at vault and arch springing, country rock side at haunch, and passes through stirrup banding fixed；The Z
Shaped connecting piece with it is vertical to angle ± 30 ° with ± 75 ° at connect with the conventional ring muscle by sleeve；The spray concrete injection
On country rock and framework of steel reinforcement.
2. a kind of deformed bar skeleton sprays concrete arch rib supporting construction according to claim 1, it is characterised in that the routine ring
Different-diameter or the reinforcing bar of intensity can be used in muscle at vault, haunch and arch springing, and diameter can use 12 ~ 32mm.
3. a kind of deformed bar skeleton sprays concrete arch rib supporting construction according to claim 1, it is characterised in that the Z-shaped connects
Fitting is one section of Z-shaped reinforcing bar, is divided into three sections, and the angle of both ends part and interlude is 135 °, and the length of both ends part takes
10d or so, intermediate segment length take 1.414 (dh- 70), the diameter d of Z-shaped reinforcing bar takes 12 ~ 32mm, arch rib overall thickness dhTake 300 ~
700mm。
4. a kind of deformed bar skeleton sprays concrete arch rib supporting construction according to claim 1, it is characterised in that the stirrup
Minimum stirrup ratio need to be more than or equal to 0.15%.
5. a kind of deformed bar skeleton sprays concrete arch rib supporting construction according to claim 1, it is characterised in that the spray concrete is adopted
With steel fibre concrete, 1000 ~ 2000mm of width.
6. the construction method of the supporting construction according to any claim in claim 1-5, which is characterized in that including with
Lower step：1. making conventional ring muscle, Z-shaped connector and the sleeve of various pieces according to actual engineering design；2. preparing concrete
And it is thick to the flushed scar injection at least 35mm in high pressure geomantic omen, then in vault and the vertical range to angle ± 30 °, and
It is thick that few 200mm is sprayed onto at arch springing and within the scope of 0 ~ 15 ° of horizontal direction angle again；3. scene laying circumferential reinforcement, and welded with stirrup
Securely；4. jetting cement reaches 35mm up to framework of steel reinforcement is completely covered and meets cover to reinforcement.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810748009.9A CN108625882A (en) | 2018-07-10 | 2018-07-10 | A kind of deformed bar skeleton spray concrete arch rib supporting construction and construction method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810748009.9A CN108625882A (en) | 2018-07-10 | 2018-07-10 | A kind of deformed bar skeleton spray concrete arch rib supporting construction and construction method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN108625882A true CN108625882A (en) | 2018-10-09 |
Family
ID=63688780
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810748009.9A Pending CN108625882A (en) | 2018-07-10 | 2018-07-10 | A kind of deformed bar skeleton spray concrete arch rib supporting construction and construction method |
Country Status (1)
| Country | Link |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109469221A (en) * | 2018-10-27 | 2019-03-15 | 张荐 | Connector and preparation method thereof |
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| US4112694A (en) * | 1976-05-07 | 1978-09-12 | Gd Anker Gebirgs-Dubel-Anker Gmbh & Co. Kg | Tunnel-lagging element and system |
| GB2036829A (en) * | 1978-12-27 | 1980-07-02 | Evg Entwicklung Verwert Ges | Arches for Galleries, Tunnels or the Like |
| DE59009832D1 (en) * | 1989-07-27 | 1995-12-07 | Bucher Franz | Reinforcement element to form expansion frames in tunnel construction. |
| CN101493011A (en) * | 2008-12-30 | 2009-07-29 | 中国科学院武汉岩土力学研究所 | Soft expansion type wall rock tunnel support method |
| CN201521305U (en) * | 2009-10-27 | 2010-07-07 | 华东宜兴抽水蓄能有限公司 | Reinforcement arch rib structure for timbering weak surrounding rocks |
| JP2011157755A (en) * | 2010-02-02 | 2011-08-18 | Nippon Steel Corp | Steel segment and composite segment |
| CN203822325U (en) * | 2014-02-17 | 2014-09-10 | 山东大学 | Steel grating steel arch frame combined support for initial stage of expansibility soil layer tunnel |
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-
2018
- 2018-07-10 CN CN201810748009.9A patent/CN108625882A/en active Pending
Patent Citations (10)
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| GB2036829A (en) * | 1978-12-27 | 1980-07-02 | Evg Entwicklung Verwert Ges | Arches for Galleries, Tunnels or the Like |
| DE59009832D1 (en) * | 1989-07-27 | 1995-12-07 | Bucher Franz | Reinforcement element to form expansion frames in tunnel construction. |
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| JP2011157755A (en) * | 2010-02-02 | 2011-08-18 | Nippon Steel Corp | Steel segment and composite segment |
| CN203822325U (en) * | 2014-02-17 | 2014-09-10 | 山东大学 | Steel grating steel arch frame combined support for initial stage of expansibility soil layer tunnel |
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| Title |
|---|
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109469221A (en) * | 2018-10-27 | 2019-03-15 | 张荐 | Connector and preparation method thereof |
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Application publication date: 20181009 |