CN116025364A - Large-section tunnel lining block construction supporting method - Google Patents
Large-section tunnel lining block construction supporting method Download PDFInfo
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- CN116025364A CN116025364A CN202310058551.2A CN202310058551A CN116025364A CN 116025364 A CN116025364 A CN 116025364A CN 202310058551 A CN202310058551 A CN 202310058551A CN 116025364 A CN116025364 A CN 116025364A
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- 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
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Abstract
The invention aims to provide a large-section tunnel lining block construction support method, which belongs to the technical field of tunnel support systems, and combines lining block construction structure support on the basis of double-side-wall pilot pit method 9 part excavation of tunnel excavation construction, and the support state of supporting surrounding rocks of a tunnel is ensured all the time in the excavation process through multiple support changes in the construction process. Under complex or weak geological conditions, all construction procedures are carried out under the condition of supporting or changing supports, the disturbance to surrounding rock is small, and the stress release of the surrounding rock is small; the excavation supporting and the second lining construction process of the construction method can be connected, meanwhile, a construction channel is reserved in a space through a bracket door opening mode, continuity of tunnel face excavation construction is guaranteed, construction time is short, and safety is high.
Description
Technical Field
The invention belongs to the technical field of tunnel supporting systems, and particularly relates to a large-section tunnel lining block construction supporting method.
Background
The tunnel construction technology in the world is developed at a high speed, gradually develops to the directions of high speed, automation and intelligence, and can overcome various difficult and bad geological capabilities, the technology is continuously improved, and the tunnel construction speed is also continuously improved. The mechanical level of tunnel construction in China is continuously improved, and the method is a development trend of tunnel construction, especially long and large tunnel construction. However, the more advanced, the better, the higher and the better the configuration of the mechanical equipment of the tunnel construction is not. Different modes should be used depending on the length and cross-sectional area of the tunnel. The economic aspect of the equipment and the rationality of the matched technology must be considered on the whole, and the influences of factors such as the process time, the working efficiency and the construction period requirement of the mechanical equipment, the mutual matching between functions and performances, the energy consumption, the universality, the easy operability, the flexibility, the durability, the maintenance difficulty, the labor resource and the like are fully considered; meanwhile, attention should be paid to the function of adapting to geological changes to a great extent when the equipment is configured and safe and rapid construction is realized. Construction technology research for reinforcing tunnel construction under poor geological conditions is imperative.
Disclosure of Invention
The invention aims to provide a large-section tunnel lining block construction support method which is high in construction safety, small in surrounding rock deformation and high in construction speed.
In order to achieve the above purpose, the invention provides a method for constructing a supporting structure by lining and blocking a large-section tunnel, which is mainly used for combining supporting of the lining and blocking construction structure on the basis of 9 parts of excavation of double side wall pilot pit method of tunnel excavation construction, and ensuring the supporting state of surrounding rocks of the tunnel all the time in the excavation process through multiple support changing in the construction process, thereby reducing the deformation of the surrounding rocks and ensuring the persistence of tunnel excavation.
The invention adopts the following technical scheme:
a large-section tunnel lining block construction supporting method comprises the following steps:
dividing the section of the station into a left excavation unit, a middle excavation unit and a right excavation unit, wherein the left excavation unit is respectively provided with 1, 3 and 5 guide pits from top to bottom, the right excavation unit is respectively provided with 2, 4 and 6 guide pits from top to bottom, and the middle excavation unit is respectively provided with 7, 8 and 9 guide pits from top to bottom;
secondly, performing advanced support on the guide pits of the upper steps 1 and 2, then performing excavation operation, and timely performing closed loop support;
thirdly, excavating guide pits at the 3 part and the 4 part of the centering step and timely sealing and supporting the guide pits into a ring;
fourthly, excavating the pilot pits of the lower steps 5 and 6 and timely performing closed loop supporting, and avoiding the condition of over-excavation when the pilot pits of the lower steps 5 and 6 are excavated to the arch springing position;
fifthly, after the primary support of the 5 and 6 guide pits is completed, the construction of the secondary lining structure and the inverted arch backfilling is started, and the secondary lining part of the inverted arch is respectively propped against the primary supports of the middle rock column and the side wall;
step six, after the construction of the inverted arch of the pilot pit and the side wall of the 5 part and the 6 part is completed, the second temporary inverted arch is replaced and propped against the completed concrete side wall and the middle rock column, and then the second temporary inverted arch is removed;
seventh, constructing a secondary lining structure of 3 and 4 guide pit side walls by adopting a full-hall type bracket, wherein the lining construction height is 1m below the first temporary inverted arch;
eighth, constructing 1, 2 guide pit lining structures, wherein in the middle step and lower step construction process, lattice columns are adopted vertically to continuously heighten, and finally, arch part concrete of 1, 2 guide pit secondary lining is jacked;
ninth, excavating the pilot pit at the 7 part of the upper step and timely sealing and supporting the pilot pit into a ring;
tenth, dismantling the vertical support of the middle partition wall, and constructing a 7-part pilot pit secondary lining structure;
eleventh step, 8 guide pits of the unit in excavation are removed, vertical lattice column supports on two sides are removed, and when the unit is excavated to a position below the elevation of the middle plate, temporary support is carried out on the two liners on the left side and the right side by adopting the supports;
twelfth, continuing to excavate 9 guide pits downwards, sealing the guide pits into rings in time, and constructing the rest inverted arch secondary lining;
and thirteenth step, removing the temporary support and constructing other internal structures of the tunnel.
Further, when 1, 2 portions of the pilot pit are constructed, the distance between the front and rear sides is not less than 12m.
Further, the radial grouting steel flowtube is adopted to perform grouting reinforcement on the middle rock column in the process of excavating and supporting the left and right side units, so that the stability of the middle rock column is ensured.
Further, the lining construction heights of the 5-part pilot pit side wall and the 6-part pilot pit side wall are 3 and 4-part pilot pit temporary inverted arches are 1m below.
Further, the middle partition wall vertical supports are removed, and the length of each removal is not more than 6m.
Further, the vertical lattice column cross section is the rectangle, including angle steel and a plurality of lacing plate, the quantity of angle steel is four, and the right angle end of angle steel is located four apex angles of rectangle respectively, and the right angle limit of angle steel is connected through the lacing plate, and the lateral wall of angle steel is equipped with the stiffening plate.
Further, the batten plates are equally spaced.
Further, the vertical lattice column is connected with the primary support middle partition through a secondary lining horizontal support and a steel waist beam, one end of the steel waist beam is connected with the primary support middle partition, the other end of the steel waist beam is connected with the secondary lining horizontal support through a bolt, and the secondary lining horizontal support is positioned at the top end of the stiffening plate.
Further, a top anchor plate is arranged at the top end of the vertical lattice column, and the top anchor plate is connected with the secondary lining/inverted arch backfill layer through a plurality of anchor bars.
The beneficial effects of the invention are as follows:
1. the surrounding rock is small in deformation. Under complex or weak geological conditions, all construction procedures are carried out under the condition of supporting or changing supports, the disturbance to surrounding rock is small, the stress release of the surrounding rock is small, and the deformation is extremely small;
2. the safety performance is high: compared with the current popular construction method of the large-section lining trolley, when the temporary middle rock pillar is removed, the tunnel large section is formed as the least adverse working condition of tunnel construction, larger vault subsidence and primary support convergence tend to occur, the construction method avoids the occurrence of the least adverse working condition, and when the tunnel large section is formed, the second lining of the tunnel structure is also immediately excavated, thus greatly reducing the safety risk in construction;
3. the material can be recycled: the temporary vertical lattice column, the temporary transverse support and the 609 steel pipe used in the construction method can be erected according to the mobility of the site construction progress, the one-time investment is low, the materials can be recycled, and the cost is reduced to a certain extent;
4. can be operated continuously. The excavation supporting and the secondary lining construction process of the construction method can be connected, meanwhile, in space, a construction channel is reserved in a bracket door opening mode, continuity of tunnel face excavation construction is guaranteed, and the construction period can be shortened to a certain extent.
Drawings
FIG. 1 is a schematic illustration of a double sidewall pilot pit method 9 section excavation;
FIG. 2 is a left and right unit excavation supporting step diagram;
FIG. 3 is a diagram of a left and right unit two-lining construction sequence;
FIG. 4 is a step diagram of medium cell excavation and two liner construction;
FIG. 5 is a working chart of the remaining 9 parts and other secondary lining construction of the tunnel;
FIG. 6 is a sequential elevation view of a tunnel Shi Gongbu;
FIG. 7 is a plan view of a tunnel construction procedure;
FIG. 8 is a schematic structural view of a vertical lattice column;
FIG. 9 is a cross-sectional view taken along A-A of FIG. 8;
FIG. 10 is a schematic illustration of the connection of the vertical lattice column to the primary support partition;
FIG. 11 is a schematic illustration of a vertical lattice construction in connection with a secondary liner/inverted arch backfill layer;
in the figure: 1-a first temporary invert; 2-a second temporary invert; 3-primary support inverted arch; 4-inverted arch; 5-inverted arch backfilling; 6-a second side wall lining; 7-temporary vertical support; 8-horizontally changing the support; 9-1 part two lining; 10-7 parts of second lining; 11-609 steel tube support replacement; 12-angle steel; 13-a lacing plate; 14-stiffening plates; 15-primary support of a septum; 16-horizontal support of the second lining; 17-a steel waist beam; 18-top anchor plate; 19-anchor bars.
Detailed Description
The invention will be further described with reference to the accompanying drawings.
The invention provides a method for constructing a supporting structure by lining and blocking a large-section tunnel, which is mainly used for combining supporting of the lining and blocking the construction structure on the basis of 9 parts of excavation of double side wall pilot pit method of tunnel excavation construction, and the supporting of the lining and blocking the construction structure is realized through multiple supporting changes in the construction process, so that the state of supporting primary supporting of surrounding rocks of the tunnel in the excavation process is ensured all the time, the deformation of the surrounding rocks is reduced, and the continuity of tunnel excavation is ensured.
Firstly, dividing the section of a station into a left excavation unit, a middle excavation unit and a right excavation unit, wherein the left excavation unit comprises 1 part, 3 parts and 5 parts from top to bottom, the right excavation unit comprises 2 parts, 4 parts and 6 parts from top to bottom, and the middle excavation unit comprises 7 parts, 8 parts and 9 parts from top to bottom; the subsection principle can be adjusted by combining the condition of construction machinery, and the shape of the pilot pit is close to an elliptic section; the step on the core rock pillar is preferably controlled to be 1.5m, so that operators can conveniently connect the left side arch and the right side arch of the middle part.
Further, the upper step 1 and the upper step 2 are subjected to advanced support and then are subjected to excavation operation, and the closed loop support is timely carried out, and when the upper step 1 and the upper step 2 are subjected to construction, the front-back pulling distance is not suitable to be smaller than 12m.
Further, when the guide pits of the 3 part and the 4 part of the centering step are excavated and closed and looped and supported in time, the protection of the temporary inverted arch of the 1 part and the 2 part should be paid attention to on site during construction of the guide pits of the 3 part and the 4 part, so that the mechanical collision is avoided.
Further, excavating the pilot pits of the lower steps 5 and 6 and timely sealing and supporting the pilot pits in a ring, wherein the condition of over-excavation should be avoided when the pilot pits of the lower steps 5 and 6 are excavated to the arch springing position; grouting reinforcement is carried out on the middle rock column by adopting a radial grouting steel flowtube in the process of excavating and supporting the left and right side units, so that the stability of the middle rock column is ensured;
further, after the primary support of the 5 part and the 6 part is completed, the construction of the secondary lining structure and the inverted arch backfilling is started, the primary supports of the middle rock column and the side wall are respectively propped up by the two substrate parts of the inverted arch, the joint is reserved by the main ribs of the joint part, the waterproof treatment of the longitudinal construction joint is finished, and the lining construction height of the side wall of the 5 part and the 6 part is 3m and the temporary inverted arch of the 4 part is 1m.
Further, after the construction of the 5 and 6 inverted arches and the side wall secondary lining is completed, the second temporary inverted arch is replaced and propped against the completed concrete side wall and the middle rock column, and then the second temporary inverted arch is removed;
further, constructing a 3-part side wall and 4-part side wall two-lining structure by adopting a full-hall type bracket, reserving personnel and vehicle channels by adopting a portal frame below the bracket, so as to facilitate the front face excavation supporting operation, and lining construction height reaches 1m below a first temporary inverted arch;
further, in the construction process of the lining structures of 1 part and 2 parts, the vertical lattice columns are adopted to be continuously heightened, and finally the arch concrete of the lining structures of 1 part and 2 parts is propped up, so that the deformation of the concrete at the cantilever end of the arch part after the bracket is dismantled is prevented, and meanwhile, a support changing condition is provided for the rock columns in the excavation;
further, the surrounding rock at the 7 parts of the upper step is subjected to advanced support, the pilot pit is excavated and timely closed into a ring for support, the upper step of the core rock column is preferably controlled to be 1.5m, and the middle part of the upper step is convenient for operators to connect the left side arch and the right side arch. The core rock pillar arch part is excavated to not more than 2 arch frames, and the total excavation height is not more than 4m, so that the construction of the second lining is facilitated;
further, the vertical support of the middle partition wall is removed, the length of the vertical support is not more than 6m each time, and 7 secondary lining structures are constructed by adopting a full framing;
further, 8 parts of the unit in excavation are excavated, and the length of each cycle of the middle and lower parts of the core is controlled within 3 m. Removing the vertical lattice column supports on the two sides, and supporting the two liners on the left side and the right side by adopting 609 steel pipes when the vertical lattice column supports on the two sides are excavated to a position below the elevation of the middle plate;
further, the 9 parts are continuously excavated downwards and timely sealed to form a ring, the rest inverted arch secondary lining is constructed, and the construction of the 9 parts secondary lining can be constructed by adopting a skip method;
further, the 609 steel pipe support in the middle of the tunnel is removed, and other internal structures of the tunnel are constructed.
The temporary inverted arch used for tunnel excavation support takes the steel arch frame and the steel bar net sheet as a framework, and concrete is sprayed to strengthen the integrity.
The temporary vertical support is a rigid lattice column formed by processing angle steel, so that stability of the lattice column is enhanced, and simultaneously, a scissor support in an angle steel form and a longitudinal I-steel beam are added on the lattice column for drawknot.
The temporary support is erected on the longitudinal steel cross beam, and the side of the middle rock column is tightly propped up through the reserved steel plate.
After the temporary vertical support is installed, concrete of the 1 part and the 2 parts can be poured, so that the vertical support can be stressed in time, and cantilever conditions of the left unit and the right unit are avoided.
When the middle unit is excavated, the vertical supports on the two sides and the middle rock column support form a support replacement, so that the stress of the vertical rock mass is ensured, and the second lining is constructed immediately after the excavation is completed, so that the primary support and the inverted arch are basically completed into a ring.
And finally, before 9 parts are excavated, a 609 steel pipe is adopted, so that the upper structure is temporarily closed to form a ring, a support is formed for the lower structure, and when 9 parts are excavated by an inverted arch and two lining construction are carried out, the construction of a jump bin is carried out.
Claims (9)
1. A large-section tunnel lining block construction supporting method is characterized by comprising the following steps of: the method comprises the following steps:
dividing the section of the station into a left excavation unit, a middle excavation unit and a right excavation unit, wherein the left excavation unit is respectively provided with 1, 3 and 5 guide pits from top to bottom, the right excavation unit is respectively provided with 2, 4 and 6 guide pits from top to bottom, and the middle excavation unit is respectively provided with 7, 8 and 9 guide pits from top to bottom;
secondly, performing advanced support on the guide pits of the upper steps 1 and 2, then performing excavation operation, and timely performing closed loop support;
thirdly, excavating guide pits at the 3 part and the 4 part of the centering step and timely sealing and supporting the guide pits into a ring;
fourthly, excavating the pilot pits of the lower steps 5 and 6 and timely performing closed loop supporting, and avoiding the condition of over-excavation when the pilot pits of the lower steps 5 and 6 are excavated to the arch springing position;
fifthly, after the primary support of the 5 and 6 guide pits is completed, the construction of the secondary lining structure and the inverted arch backfilling is started, and the secondary lining part of the inverted arch is respectively propped against the primary supports of the middle rock column and the side wall;
step six, after the construction of the inverted arch of the pilot pit and the side wall of the 5 part and the 6 part is completed, the second temporary inverted arch is replaced and propped against the completed concrete side wall and the middle rock column, and then the second temporary inverted arch is removed;
seventh, constructing a secondary lining structure of 3 and 4 guide pit side walls by adopting a full-hall type bracket, wherein the lining construction height is 1m below the first temporary inverted arch;
eighth, constructing 1, 2 guide pit lining structures, wherein in the middle step and lower step construction process, lattice columns are adopted vertically to continuously heighten, and finally, arch part concrete of 1, 2 guide pit secondary lining is jacked;
ninth, excavating the pilot pit at the 7 part of the upper step and timely sealing and supporting the pilot pit into a ring;
tenth, dismantling the vertical support of the middle partition wall, and constructing a 7-part pilot pit secondary lining structure;
eleventh step, 8 guide pits of the unit in excavation are removed, vertical lattice column supports on two sides are removed, and when the unit is excavated to a position below the elevation of the middle plate, temporary support is carried out on the two liners on the left side and the right side by adopting the supports;
twelfth, continuing to excavate 9 guide pits downwards, sealing the guide pits into rings in time, and constructing the rest inverted arch secondary lining;
and thirteenth step, removing the temporary support and constructing other internal structures of the tunnel.
2. The large-section tunnel lining block construction support method according to claim 1, wherein the large-section tunnel lining block construction support method comprises the following steps: 1. when the 2-part pilot pit is constructed, the front-back pulling distance is not less than 12m.
3. The large-section tunnel lining block construction support method according to claim 1, wherein the large-section tunnel lining block construction support method comprises the following steps: and the radial grouting steel flowtube is adopted to perform grouting reinforcement on the middle rock column in the process of excavating and supporting the left and right side units, so that the stability of the middle rock column is ensured.
4. The large-section tunnel lining block construction support method according to claim 1, wherein the large-section tunnel lining block construction support method comprises the following steps: 5. 6 portions of pilot pit side walls are lined and constructed to be 3 and 4 portions of pilot pit temporary inverted arches to be 1m below.
5. The large-section tunnel lining block construction support method according to claim 1, wherein the large-section tunnel lining block construction support method comprises the following steps: and (3) dismantling the middle partition wall vertical support, wherein the dismantling length is not more than 6m each time.
6. The large-section tunnel lining block construction support method according to claim 1, wherein the large-section tunnel lining block construction support method comprises the following steps: the vertical lattice column section is the rectangle, including angle steel and a plurality of batten board, the quantity of angle steel is four, and the right angle end of angle steel is located four apex angles of rectangle respectively, and the right angle limit of angle steel is connected through the batten board, and the lateral wall of angle steel is equipped with the stiffening plate.
7. The large-section tunnel lining block construction support method according to claim 6, wherein the large-section tunnel lining block construction support method comprises the following steps: the lacing plates are arranged at equal intervals.
8. The large-section tunnel lining block construction support method according to claim 7, wherein the large-section tunnel lining block construction support method comprises the following steps: the vertical lattice column is connected with the primary support middle partition wall through a secondary lining horizontal support and a steel waist beam, one end of the steel waist beam is connected with the primary support middle partition wall, the other end of the steel waist beam is connected with the secondary lining horizontal support through a bolt, and the secondary lining horizontal support is positioned at the top end of the stiffening plate.
9. The large-section tunnel lining block construction support method according to claim 8, wherein the large-section tunnel lining block construction support method comprises the following steps: and the top end of the vertical lattice column is provided with a top anchor plate, and the top anchor plate is connected with the secondary lining/inverted arch backfill layer through a plurality of anchor bars.
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| CN202310058551.2A CN116025364A (en) | 2023-01-16 | 2023-01-16 | Large-section tunnel lining block construction supporting method |
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| CN202310058551.2A CN116025364A (en) | 2023-01-16 | 2023-01-16 | Large-section tunnel lining block construction supporting method |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109958451A (en) * | 2017-12-22 | 2019-07-02 | 中铁上海工程局集团有限公司 | Mountain area underpass of freeways roadbed combined supporting settlement Control device and construction technology |
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- 2023-01-16 CN CN202310058551.2A patent/CN116025364A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109958451A (en) * | 2017-12-22 | 2019-07-02 | 中铁上海工程局集团有限公司 | Mountain area underpass of freeways roadbed combined supporting settlement Control device and construction technology |
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