CN110094213A - The spaces union supporting construction and method for protecting support in a kind of rich water broken formation tunnel - Google Patents

Abstract

The invention discloses a space joint support structure and a support method for a tunnel in a water-rich broken stratum, relates to the technical field of tunnel construction, and solves the problem that the surrounding rock easily undergoes large deformation when the surrounding rock is supported by conventional spray anchors in the water-rich broken ground section. The surrounding rock pressure is relatively high, and water leakage is difficult to effectively prevent and control, which endangers the stability of the tunnel structure and construction safety. The key points of its technical plan are: including the first concrete layer, steel mesh and steel arches arranged at intervals; between the steel arches and the steel arches, there are longitudinal connecting steel beams staggered along the tunnel axis; the longitudinal connecting steel beams Anchor rods are connected; the surface of the steel mesh is sprayed with a steel fiber concrete layer covering the steel arch frame, steel mesh and longitudinally connected steel beams; the surface of the steel fiber concrete is laid with a waterproof and drainage structure layer; the surface of the waterproof and drainage structure layer is poured with a second lining concrete layer. It can not only effectively control the deformation of the surrounding rock in the tunnel, but also have excellent waterproof and drainage functions to ensure the stability of the tunnel structure and the safety of construction.

Description

Space combined support structure and support method for a water-rich fractured stratum tunnel

technical field

The invention relates to the technical field of tunnel construction, and more specifically relates to a space combined support structure and a support method for tunnels in water-rich and fractured strata.

Background technique

When excavating a large-section tunnel body in an unbiased water-rich stratum section, when the surrounding rock mass is weak, especially in a fully weathered stratum or a strongly weathered stratum, it is very easy to cause excessive convergence deformation in the tunnel, and even Causing landslide accidents, when the buried depth is not large, it is very easy to cause cracks on the surface of the mountain above the tunnel, and even landslides. When such topographic bias is encountered, and the geology is rich in water and the surrounding rock is broken, it is usually necessary to carry out tunnel support procedures to ensure the safety of tunnel construction.

At present, in the conventional shotcrete anchor support, shotcrete, steel support and anchor rods are mainly used for effective flexible support, so that the self-stabilizing bearing capacity of the surrounding rock can be exerted.

In the prior art, when the tunnel is excavated in the water-rich broken section, due to the abundant groundwater, the self-stabilization ability of the surrounding rock is poor, and the excavation disturbance is easy to cause the surrounding rock to loosen a lot, and the arching effect is poor. In this way, the support structure will bear a large pressure of the surrounding rock, and the surrounding rock often undergoes large deformation, and it is difficult to effectively prevent the leakage of water, which endangers the stability of the tunnel structure and the safety of the operators.

Contents of the invention

The object of the present invention is to provide a space combined support structure and support method for a water-rich fractured stratum tunnel, which can fully exert the spatial joint effect of support structure points, lines and surfaces, thereby greatly increasing the rigidity of the support system, Improve the bearing capacity and effectively control the deformation of the broken surrounding rock; at the same time, it can prevent the tunnel from leaking, thereby ensuring the stability of the tunnel structure and construction safety, and has high construction efficiency and good applicability.

The above-mentioned technical purpose of the present invention is achieved through the following technical solutions: a space combined support structure for a water-rich fractured ground tunnel, comprising a primary concrete layer with a thickness of 3-5cm sprayed on the surface of the surrounding rock in the tunnel, laying The reinforcement mesh on the surface of the first concrete layer and a plurality of steel arches arranged at intervals, the steel arches are in contact with the surface of the reinforcement mesh; longitudinal connecting steel beams are arranged circumferentially between the steel arches and the steel arches , the longitudinal connecting steel beams are staggered along the axis of the tunnel; the longitudinal connecting steel beams are connected with anchor rods whose anchoring section is located inside the surrounding rock of the tunnel; the surface of the steel mesh is sprayed with steel arches, steel mesh and longitudinal connection The steel fiber concrete layer covered by the steel beam, the thickness of the steel fiber concrete layer is 20-25cm; the surface of the steel fiber concrete is laid with a waterproof and drainage structure layer; the surface of the waterproof and drainage structure layer is poured with a second lining concrete layer.

By adopting the above-mentioned technical scheme, when the support construction is carried out in the water-rich and fractured strata of the tunnel, the surrounding rock in the tunnel can be easily sealed through the first layer of concrete layer, so as to facilitate the formation of primary flexible support for the tunnel; The arch frame is convenient to form a joint support structure in the tunnel, so that it is convenient to increase the contact degree between the steel mesh and the steel arch frame and the surrounding rock in the tunnel, so that the mechanical performance of the steel mesh and the steel arch frame is better; at the same time , which can transform the line contact between the steel arch and the surrounding rock in the tunnel into surface contact; by connecting the steel beams longitudinally, it is convenient to form an integral support structure with the supporting part of the steel arch; at the same time, by connecting with the steel arch The vertically connected steel beams facilitate the large increase of the supporting points of the steel arch, thereby significantly improving the bearing capacity of the steel arch and forming a rigid support structure on the second floor; through the anchor rods, it is convenient to increase the longitudinally connected steel beams and the tunnel The degree of contact with the surrounding rock; at the same time, through the anchor rod, the integrity between the longitudinally connected steel beams, steel arches, steel mesh and the surrounding rock in the tunnel can be enhanced, thereby enhancing the effect of joint support; through the steel fiber concrete layer , to facilitate the formation of a space joint support system with high stability, rigidity and bearing capacity among the steel arch frame, longitudinal connecting steel beams, anchor rods and steel mesh; at the same time, through the steel fiber concrete layer, the surrounding rock in the tunnel can be The pressure is distributed twice, so that the pressure is evenly distributed to the space joint support system composed of steel arches, steel mesh, longitudinally connected steel beams and anchor rods, so that the support performance of the space joint support system is stable; through Set up an efficient waterproof and drainage structure layer to facilitate the discharge of groundwater infiltrated into the support structure from the tunnel, thus preventing the tunnel structure from being endangered by tunnel leakage; The space joint support system structure composed of frame, steel mesh, longitudinally connected steel beams and anchor rods is closed to ensure the support performance of the space joint support system structure; through the steel arch frame, steel mesh, longitudinally connected steel The space combined support structure composed of beams and anchor rods can not only effectively control the deformation of the tunnel structure and surrounding rock, but also has good waterproof and drainage performance, ensuring the stability of the tunnel structure and construction safety.

The present invention is further set as: the grid size of the steel mesh is 25cm.

By adopting the above-mentioned technical scheme, the line contact between the steel arch frame and the surrounding rock in the tunnel can be easily transformed into surface contact through the steel mesh with a grid size of 25 cm.

The present invention is further set as: the distance between the steel arches is 50-70cm.

By adopting the above technical scheme, the distance between the steel arches is 50-70 cm, which facilitates the force balance of each steel arch, thereby making the supporting performance of the steel arches stable.

The present invention further provides that: the longitudinal connecting steel beam is a space lattice structure; the longitudinal connecting steel beam includes an upper web, a side edge plate connected to the upper web, and a lower web connected to the side edge plate; The upper web and the lower web are provided with reserved holes for bolting; the two ends of the upper web are provided with bolt holes.

By adopting the above-mentioned technical scheme, through the reserved holes, it is convenient to connect and fix the anchor rod and the longitudinal connecting steel beam; through the bolt holes, it is convenient to connect and fix between the longitudinal connecting steel beam and the steel arch frame through bolts.

The present invention is further set as: the length of the anchor rods is 3.0-3.5m; the distance between the staggered anchor rods is not greater than 1.2m.

By adopting the above-mentioned technical scheme, through the anchor rods with a length of 3-3.5m, and the distance between the staggered anchor rods is no more than 1.2m, it is convenient to increase the contact degree between the longitudinal connecting steel beam and the surrounding rock, and at the same time it can strengthen Longitudinally connect the integrity of steel beams, steel arches, steel mesh and tunnel surrounding rock, thereby enhancing the joint support effect.

The present invention is further configured as follows: the anchor rod located in the water-rich and weak surrounding rock section of the tunnel is provided with a multi-point displacement meter for detecting displacement changes in the surrounding rock body.

By adopting the above-mentioned technical scheme and multi-point displacement meter, it is convenient to monitor the change of displacement in the surrounding rock body of the tunnel, so as to facilitate the evaluation of the loosening range of the surrounding rock, and provide a basis for the improvement of the bolt support parameters of the subsequent similar surrounding rock sections.

The present invention is further configured as follows: the surface of the waterproof and drainage structure layer is provided with a plurality of convex structures and criss-cross diversion grooves; the bottom of the waterproof and drainage structure layer is connected with drainage pipes located at both ends of the bottom of the tunnel.

By adopting the above-mentioned technical scheme, by providing a plurality of convex structures and criss-cross diversion grooves on the surface of the waterproof and drainage structure layer, the tunnel has good waterproof and drainage performance, thereby preventing the tunnel from leaking and endangering the internal structure of the tunnel. Safety.

A support method for a space joint support structure of a water-rich fractured stratum tunnel, comprising the following steps:

1) Apply flexible support for the first layer, that is, spray concrete with a thickness of 3-5cm on the inner wall of the tunnel to seal the surrounding rock;

2) Laying steel mesh, erecting steel arch frame, laying steel mesh with a grid size of 25cm on the concrete surface described in step 1), and then erecting multiple steel meshes in contact with the surface of the steel mesh at intervals of 50-70cm Arch;

3) Build a two-story rigid support structure, and arrange longitudinally connecting steel beams staggered along the tunnel axis in the circumferential direction between every two steel arches according to the designed spacing, and then connect the longitudinally connecting steel beams to the steel arches through bolts Preliminary connection and fixation of the overlapping parts of the steel support part;

4) As bolts, bolts are staggeredly distributed on the longitudinal connecting steel beams, the anchoring section of the bolts goes deep into the surrounding rock of the tunnel, the length of the bolts is 3.0-3.5m, and the distance between the bolts is not Greater than 1.2m. At the same time, a multi-point displacement meter can be placed on the bolt of a typical section of the water-rich and broken stratum of the tunnel to detect the change of the displacement in the surrounding rock body and evaluate the loosening range of the surrounding rock. Provide a basis for the improvement of maintenance parameters;

5) Spray steel fiber concrete to form a stable space joint support system among the steel arch frame, longitudinal connecting steel beams, anchor rods and steel mesh, improve the stiffness and bearing capacity of the space joint support system, and spray steel fiber concrete The thickness is not less than 20-25cm;

6) laying on the surface of the steel fiber concrete described in step 5) the waterproof and drainage structure layer for the groundwater infiltrated into the primary support to be discharged to the drainage side ditch on both sides of the tunnel;

7) Performing secondary lining, pouring secondary lining concrete on the surface of the waterproof and drainage structure layer described in step 6), and pouring inverted arches to form a closed support structure.

By adopting the above-mentioned technical scheme, in the process of constructing the space joint support structure for the water-rich fractured stratum tunnel, the first layer of flexible support is applied in step 1), which is convenient to seal the surrounding rock and prevent the deterioration of the surrounding rock, thereby facilitating The follow-up construction process is carried out smoothly; through the reinforcement mesh laid in step 2) and the steel arch frame erected, it is convenient to increase the contact degree between the reinforcement mesh, the steel arch frame and the surrounding rock in the tunnel, so that the steel arch frame and The line contact between the surrounding rocks in the tunnel is transformed into surface contact; through the two-story rigid support structure implemented in step 3), the vertically connected steel beams connect the steel arch frame into a whole, which facilitates the stress of the steel arch frame. The support points are greatly increased, so that the bearing capacity of the steel arch can be significantly improved; the anchor rods made in step 4) are convenient to increase the contact degree between the longitudinal connecting steel beams and the surrounding rock of the tunnel, thereby strengthening the longitudinal connecting steel beams and steel arches. , steel mesh and the integrity of the surrounding rock of the tunnel, thereby enhancing the joint support effect; through the multi-point displacement meter in step 4), the change of displacement in the surrounding rock of the tunnel can be detected, which is beneficial to the loosening range of the surrounding rock evaluation, so as to provide a basis for the perfection of bolting parameters in the construction of subsequent similar surrounding rock sections; through the steel fiber concrete sprayed in step 5), the surrounding rock pressure in the tunnel can be redistributed, and Evenly distribute the surrounding rock pressure in the tunnel to the space combined support system composed of steel arch frame, steel mesh, longitudinally connected steel beams and anchor rods, so that the support performance of the space combined support system is stable; through step 6 The waterproof and drainage structure layer laid in ) makes the tunnel have good waterproof performance, and the groundwater infiltrated into the support structure can be quickly discharged from the tunnel; through the pouring of the second lining and inverted arch concrete in step 7), the steel arch frame, steel mesh, The space joint support system structure composed of vertically connected steel beams and anchor rods is closed, thereby helping to ensure the support performance of the space joint support system structure; the support method of the space joint support structure through the water-rich fractured stratum tunnel , can give full play to the spatial joint effect of points, lines and surfaces of the support structure, greatly increase the stiffness and bearing capacity of the support system, effectively control the deformation of the broken surrounding rock, and have good waterproof and drainage performance, prevent the tunnel from leaking, and ensure The stability and construction safety of the structure in the tunnel; at the same time, the construction efficiency is high and the applicability is good.

The present invention is further set as: the longitudinal connecting steel girder described in step 3) is a space lattice structure; the longitudinal connecting steel girder includes an upper web, a lower web and a side edge plate, and the upper web and the lower web are Reserved holes are reserved for bolt installation; bolt holes are reserved on both sides of the upper web close to the steel arch.

By adopting the above-mentioned technical scheme and by reserving the holes, it is convenient for subsequent installation of anchor rods, thereby facilitating the connection and fixing operation between the anchor rods and the longitudinally connected steel beams; through the bolt holes, it is convenient to connect the longitudinal bolts through bolts during the construction process. The operation of connecting and fixing the connection between the steel beam and the steel arch.

The present invention is further provided that: the surface of the waterproof and drainage structure layer described in step 6) is provided with a convex structure and criss-cross diversion grooves.

By adopting the above technical solution, the multiple convex structures and criss-cross diversion grooves provided can quickly discharge the groundwater seeped into the supporting structure out of the tunnel, thereby preventing the tunnel from leaking and endangering the safety of the tunnel structure.

In summary, the present invention has the following beneficial effects: through the initial concrete layer, it is convenient to seal the surrounding rock in the tunnel to prevent the deterioration of the surrounding rock; through the steel mesh and steel arch frame, it is convenient to form a joint support structure in the tunnel , so that it is convenient to increase the contact degree between the steel mesh and the steel arch and the surrounding rock in the tunnel, so that the mechanical performance of the steel mesh and the steel arch is better; at the same time, it can make the relationship between the steel arch and the tunnel surrounding rock The line contact between them is converted into surface contact; through the longitudinal connection of steel beams, it is convenient to form an integral support structure with the support part of the steel arch; at the same time, through the longitudinal connection of steel beams connected with the steel arch, it is convenient for the steel arch The force support points are greatly increased, which can significantly improve the bearing capacity of the steel arch frame and form a rigid support structure on the second floor; through the anchor rod, it is convenient to increase the contact degree between the longitudinally connected steel beam and the surrounding rock in the tunnel; at the same time, through the anchor rod , can enhance the integrity between the longitudinally connected steel beams, steel arches, steel mesh and surrounding rock in the tunnel, thereby enhancing the effect of joint support; through the steel fiber concrete layer, it is convenient to make the steel arches, longitudinally connected steel beams, A space joint support system with high stability, rigidity and bearing capacity is formed between the anchor rod and the steel mesh; at the same time, through the steel fiber concrete layer, the surrounding rock pressure in the tunnel can be redistributed, so that the pressure is evenly distributed Provide a space joint support system composed of steel arches, steel mesh, longitudinally connected steel beams and anchor rods, so that the support performance of the space joint support system is stable; through the waterproof and drainage structure layer, it is easy to seep into the support structure The underground water in the tunnel can be quickly discharged from the tunnel, so as to prevent the tunnel structure from being endangered due to the leakage of the tunnel; through the secondary lining and the inverted arch concrete layer, it is convenient to support the joint space composed of steel arch frame, steel mesh, longitudinal connecting steel beams and anchor rods. The structure of the space joint support system is closed, so as to ensure the support performance of the space joint support system structure; through the space joint support structure composed of steel arches, steel mesh, longitudinally connected steel beams and anchor rods, it is possible to effectively control The tunnel structure and surrounding rock are deformed, and it has good waterproof and drainage performance, which ensures the stability of the tunnel structure and construction safety.

Description of drawings

Fig. 1 is the structural representation among the embodiment 1 of the present invention;

Fig. 2 is a schematic cross-sectional view of the combined support structure in Embodiment 1 of the present invention;

3 is a schematic structural view of the waterproof and drainage structure layer in Example 1 of the present invention;

4 is a schematic plan view of the waterproof and drainage structure layer in Embodiment 1 of the present invention;

Fig. 5 is a schematic structural view of longitudinally connected steel beams in Embodiment 1 of the present invention;

Fig. 6 is a schematic structural view of the upper web in Embodiment 1 of the present invention;

Fig. 7 is a construction flowchart in Embodiment 2 of the present invention.

In the figure: 1. Primary concrete layer; 2. Reinforcing mesh; 3. Steel arch frame; 4. Longitudinal connecting steel beam; Lining concrete layer; 9. Upper web; 10. Lower web; 11. Side edge plate; 12. Reserved hole; 13. Bolt hole; 14. Multi-point displacement meter; 15. Convex structure; 16. Diversion groove ; 17, drainage pipe.

Detailed ways

The present invention will be described in further detail below in conjunction with accompanying drawings 1-7.

Embodiment 1: A space combined support structure of a water-rich fractured formation tunnel, as shown in Figure 1, Figure 2, Figure 3, Figure 4, Figure 5 and Figure 6, including the thickness of the surrounding rock surface sprayed on the tunnel. The primary concrete layer 1 of 3-5 cm, the reinforcement mesh 2 laid on the surface of the primary concrete layer 1 and a plurality of steel arches 3 arranged at intervals, the steel arches 3 contact with the surface of the reinforcement mesh 2 . Between the steel arch 3 and the steel arch 3, longitudinal connecting steel beams 4 are circumferentially installed, and the longitudinal connecting steel beams 4 are staggered along the axis of the tunnel. The longitudinal connecting steel beam 4 is connected with an anchor rod 5 whose anchoring section is located inside the surrounding rock of the tunnel. The surface of the steel mesh 2 is sprayed with a steel fiber concrete layer 6 covering the steel arch 3, the steel mesh 2 and the longitudinal connecting steel beams 4, and the thickness of the steel fiber concrete layer 6 is 20-25cm. The surface of the steel fiber concrete is paved with a waterproof and drainage structure layer 7 . The surface of the waterproof and drainage structure layer 7 is poured with a second lining concrete layer 8 .

In this embodiment, when the tunnel is constructed in the water-rich fractured stratum, the primary concrete layer 1 is used to seal the surrounding rock in the tunnel, thereby facilitating the formation of primary flexible support for the tunnel and preventing the deterioration of the surrounding rock. Through the reinforcement mesh 2 and the steel arch 3, it is convenient to form a joint support structure in the tunnel, so as to increase the contact degree between the reinforcement mesh 2 and the steel arch 3 and the surrounding rock in the tunnel, so that the reinforcement mesh 2 and the steel The mechanical performance of the arch frame 3 is better. At the same time, the line contact between the steel arch 3 and surrounding rock in the tunnel can be transformed into surface contact. By connecting the steel beams 4 longitudinally, it is convenient to form an integral supporting structure with the supporting part of the steel arch 3 . At the same time, through the vertically connected steel beams 4 connected to the steel arch 3, the supporting points of the steel arch 3 are greatly increased, thereby significantly improving the bearing capacity of the steel arch 3 and forming a rigid support structure on the second floor. Through the anchor rod 5, it is convenient to increase the contact degree between the longitudinal connecting steel beam 4 and the surrounding rock in the tunnel. At the same time, through the anchor rod 5, the integrity among the longitudinally connected steel beam 4, the steel arch frame 3, the steel mesh 2 and the surrounding rock in the tunnel can be enhanced, thereby enhancing the effect of joint support. Through the steel fiber concrete layer 6, it is convenient to form a space joint support system with high stability, rigidity and bearing capacity among the steel arch frame 3, the longitudinal connecting steel beam 4, the anchor rod 5 and the steel mesh 2. At the same time, through the steel fiber concrete layer 6, the surrounding rock pressure in the tunnel can be redistributed, so that the pressure can be evenly distributed to the steel arch frame 3, steel mesh 2, longitudinal connecting steel beam 4 and anchor rod 5. The space joint support system makes the support performance of the space joint support system stable. Through the waterproof and drainage structure layer 7, the underground water infiltrated into the support structure can be quickly drained out of the tunnel, so that the safety of the tunnel structure can be prevented from being endangered due to the leakage of the tunnel. Through the second lining and inverted arch concrete layer 8, it is convenient to close the space joint support system structure composed of steel arch frame 3, steel mesh 2, longitudinal connecting steel beam 4 and anchor rod 5, so as to ensure the space joint support system Structural support performance. Through the space combined support structure composed of steel arch frame 3, steel mesh 2, longitudinally connected steel beam 4 and anchor rod 5, it can not only effectively control the deformation of the tunnel structure and surrounding rock, but also quickly remove the infiltrated groundwater, ensuring that the tunnel Structural stability and construction safety.

The mesh size of the reinforcement mesh 2 is 25cm.

In this embodiment, the line contact between the steel arch 3 and the surrounding rock in the tunnel can be transformed into surface contact through the reinforcement mesh 2 with a grid size of 25 cm.

The spacing between the steel arches 3 is 50-70cm.

In this embodiment, the distance between the steel arches 3 is 50-70 cm, so that the force of each steel arch 3 is balanced, so that the supporting performance of the steel arches 3 is stable.

The longitudinal connecting steel beam 4 is a spatial lattice structure. The longitudinal connecting steel beam 4 includes an upper web 9 , a side edge plate 11 connected to the upper web 9 and a lower web 10 connected to the side edge plate 11 . The upper web 9 and the lower web 10 are provided with reserved holes 12 for anchor rods 5 to be applied. Both ends of the upper web 9 are provided with bolt holes 13 .

In this embodiment, the holes 12 are reserved to facilitate the connection and fixation between the anchor rod 5 and the longitudinal connecting steel beam 4 . Through the bolt holes 13, it is convenient to connect and fix the longitudinal connecting steel beam 4 and the steel arch 3 through bolts.

The length of the anchor rod 5 is 3.0-3.5m. The distance between the staggered anchor rods 5 is not greater than 1.2m.

In this embodiment, the passing length is 3.0-3.5m. anchor rods 5, and the distance between the staggered anchor rods 5 is no more than 1.2m, which is convenient to increase the contact degree between the longitudinal connecting steel beam 4 and the surrounding rock, and can also strengthen the longitudinal connecting steel beam 4 and steel arch 3 , The integrity between the steel mesh 2 and the surrounding rock of the tunnel, thereby enhancing the joint support effect.

The anchor rod 5 located in the water-rich and weak surrounding rock section of the tunnel is equipped with a multi-point displacement meter 14 for detecting displacement changes in the surrounding rock body.

In this embodiment, through the multi-point displacement meter 14, it is convenient to monitor the change of displacement in the surrounding rock body of the tunnel, so as to facilitate the evaluation of the loosening range of the surrounding rock, and provide a basis for improving the supporting parameters of the bolt 14 in subsequent similar surrounding rock sections.

A plurality of convex structures 15 and criss-cross diversion grooves 16 are installed on the surface of the waterproof and drainage structure layer 7 . The bottom end of the waterproof and drainage structure layer 7 is connected with drainage pipes 17 located at both ends of the bottom of the tunnel.

In this embodiment, by installing a plurality of convex structures 15 and criss-cross diversion grooves 16 on the surface of the waterproof and drainage structure layer 7, it is convenient to make the tunnel have good waterproof and drainage performance, thereby preventing the tunnel from leaking and endangering The safety of the inner structure of the tunnel.

Embodiment 2: A support method for a space joint support structure of a water-rich fractured stratum tunnel, as shown in FIG. 7 , comprising the following steps:

1) Implement flexible support for the first layer, that is, spray concrete with a thickness of 3-5cm on the inner wall of the tunnel to seal the surrounding rock.

2) Laying steel mesh 2, erecting steel arch 3, laying steel mesh 2 with a grid size of 25cm on the concrete surface in step 1), and then erecting multiple meshes in contact with the surface of steel mesh 2 at intervals of 50-70cm. A steel arch 3.

3) A two-story rigid support structure is constructed, and longitudinal connecting steel beams 4 are arranged in a circular direction along the tunnel axis at a designed interval between every two steel arches 3, and then the longitudinal connecting steel beams 4 are connected to the tunnel by bolts. The overlapping parts of the steel support parts of the steel arch 3 are initially connected and fixed.

4) Apply anchor rods 5, and apply anchor rods 5 in a staggered distribution on the longitudinal connecting steel beam 4. The anchoring section of the anchor rods 5 goes deep into the surrounding rock in the tunnel. The length of the anchor rods 5 is 3.0-3.5m. The distance between 5 is not greater than 1.2m. At the same time, a multi-point displacement meter 14 is placed on the anchor rod 5 of the typical section of the water-rich and broken stratum of the tunnel to detect the change of the displacement in the surrounding rock body and evaluate the loosening range of the surrounding rock, so as to prepare for the subsequent construction of similar surrounding rock sections. 5 provides a basis for the perfection of support parameters.

5) Spray steel fiber concrete to form a stable space joint support system among the steel arch frame 3, longitudinal connecting steel beam 4, anchor rod 5 and steel mesh 2, and improve the stiffness and bearing capacity of the space joint support system, and The thickness of sprayed steel fiber concrete is not less than 20-25cm.

6) On the surface of the steel fiber concrete in step 5), the waterproof and drainage structure layer 7 for draining the groundwater infiltrated into the primary support to the side drains on both sides of the tunnel is laid.

7) Performing secondary lining, pouring secondary lining concrete on the surface of the waterproof and drainage structure layer 7 in step 6), and pouring inverted arches to form a closed support structure.

In this embodiment, the anchor rod 5 applied in step 4) is a full-length mortar or hollow grouted anchor rod 5 . In the process of constructing space combined support structure for tunnels in water-rich and fractured strata, the first layer of flexible support is applied in step 1), which is convenient to close the surrounding rock and prevent the deterioration of the surrounding rock, thereby facilitating the smooth subsequent construction process conduct. Through the steel mesh 2 laid in step 2) and the steel arch 3 erected, it is convenient to increase the contact degree between the steel mesh 2 and the steel arch 3 and the surrounding rock in the tunnel, so that the steel arch 3 and the tunnel inner wall The line contact between rocks is transformed into surface contact. Through the two-story rigid support structure implemented in step 3), the longitudinal connecting steel beam 4 connects the steel arch 3 into a whole, which is convenient for greatly increasing the supporting points of the steel arch 3, thereby significantly improving the steel arch The carrying capacity of frame 3. Through the anchor rod 5 applied in step 4), it is convenient to increase the contact degree between the longitudinal connecting steel beam 4 and the surrounding rock of the tunnel, thereby enhancing the integrity of the longitudinal connecting steel beam 4, the steel arch frame 3, the steel mesh 2 and the surrounding rock of the tunnel, Thereby enhancing the combined support effect. Through the multi-point displacement meter 14 in step 4), the variation of the displacement in the surrounding rock body of the tunnel can be detected, thereby facilitating the evaluation of the loosening range of the surrounding rock, thereby facilitating the bolting in the construction of subsequent similar surrounding rock sections. 5 provides a basis for the perfection of support parameters. Through the steel fiber concrete sprayed in step 5), the surrounding rock pressure in the tunnel can be redistributed, and the surrounding rock pressure in the tunnel can be evenly distributed to the steel arch frame 3, steel mesh 2, and longitudinally connected steel beams. 4 and the anchor rod 5 constitute the space joint support system, which makes the support performance of the space joint support system stable. Through the waterproof and drainage structure layer 7 laid in step 6), the tunnel has good waterproof performance, and the groundwater infiltrated into the support structure can be quickly discharged from the tunnel. By pouring the second lining and inverted arch concrete in step 7), the space joint support system structure composed of steel arch frame 3, steel mesh 2, longitudinal connecting steel beam 4 and anchor rod 5 will be closed, so as to ensure the space joint support Supporting performance of the protection system. Through the support method of the space joint support structure of the water-rich fractured stratum tunnel, the space joint effect of the point, line and surface of the support structure can be fully utilized, the stiffness and bearing capacity of the support system can be greatly increased, and the broken surrounding rock can be effectively controlled. Deformation, but also has good waterproof and drainage performance, prevents leakage in the tunnel, and ensures the stability of the tunnel structure and construction safety. At the same time, the construction efficiency is high and the applicability is good.

The longitudinal connecting steel beam 4 in step 3) is a spatial lattice structure. The longitudinal connecting steel beam 4 includes an upper web 9 , a lower web 10 and a side edge plate 11 , and the upper web 9 and the lower web 10 are reserved with reserved holes 12 for anchor rods 5 . Bolt holes 13 are reserved on both sides of the upper web 9 close to the steel arch 3 .

In this embodiment, the hole 12 is reserved to facilitate subsequent installation of the anchor rod 5 , thereby facilitating the connection and fixing operation between the anchor rod 5 and the longitudinal connecting steel beam 4 . Through the bolt holes 13, it is convenient to connect and fix the longitudinally connected steel beam 4 and the steel arch 3 through bolts during the construction process.

The surface of the waterproof and drainage structure layer 7 in step 6) is provided with a convex structure 15 and criss-cross diversion grooves 16 .

In this embodiment, the plurality of convex structures 15 and the criss-cross diversion grooves 16 can efficiently and quickly discharge the groundwater infiltrated into the support structure out of the tunnel, thereby preventing the tunnel from leaking and endangering the safety of the tunnel structure.

Working principle: When the support process is carried out in the water-rich and broken stratum of the tunnel, the surrounding rock in the tunnel can be easily sealed through the primary concrete layer 1, so as to facilitate the formation of primary flexible support for the tunnel and prevent the deterioration of the surrounding rock. Through the reinforcement mesh 2 and the steel arch 3, it is convenient to form a joint support structure in the tunnel, so as to increase the contact degree between the reinforcement mesh 2 and the steel arch 3 and the surrounding rock in the tunnel, so that the reinforcement mesh 2 and the steel The mechanical performance of the arch frame 3 is better. At the same time, the line contact between the steel arch 3 and surrounding rock in the tunnel can be transformed into surface contact. By connecting the steel beams 4 longitudinally, it is convenient to form an integral supporting structure with the supporting part of the steel arch 3 . At the same time, through the vertically connected steel beams 4 connected to the steel arch 3, the supporting points of the steel arch 3 are greatly increased, thereby significantly improving the bearing capacity of the steel arch 3 and forming a rigid support structure on the second floor. Through the anchor rod 5, it is convenient to increase the contact degree between the longitudinal connecting steel beam 4 and the surrounding rock in the tunnel. At the same time, through the anchor rod 5, the integrity among the longitudinally connected steel beam 4, the steel arch frame 3, the steel mesh 2 and the surrounding rock in the tunnel can be enhanced, thereby enhancing the effect of joint support. Through the steel fiber concrete layer 6, it is convenient to form a space joint support system with high stability, rigidity and bearing capacity among the steel arch frame 3, the longitudinal connecting steel beam 4, the anchor rod 5 and the steel mesh 2. At the same time, through the steel fiber concrete layer 6, the surrounding rock pressure in the tunnel can be redistributed, so that the pressure can be evenly distributed to the steel arch frame 3, steel mesh 2, longitudinal connecting steel beam 4 and anchor rod 5. The space joint support system makes the support performance of the space joint support system stable. Through the waterproof and drainage structure layer 7, the underground water infiltrated into the support structure can be quickly drained out of the tunnel, so that the safety of the tunnel structure can be prevented from being endangered due to the leakage of the tunnel. Through the second lining and inverted arch concrete layer 8, it is convenient to close the space joint support system structure composed of steel arch frame 3, steel mesh 2, longitudinal connecting steel beam 4 and anchor rod 5, so as to ensure the space joint support system Structural support performance. Through the space combined support structure composed of steel arch frame 3, steel mesh 2, longitudinal connecting steel beam 4 and anchor rod 5, it can not only effectively control the deformation of surrounding rock in the tunnel, but also have good waterproof and drainage performance, ensuring the tunnel structure Stability and construction safety.

This specific embodiment is only an explanation of the present invention, and it is not a limitation of the present invention. Those skilled in the art can make modifications to this embodiment without creative contribution as required after reading this specification, but as long as they are within the rights of the present invention All claims are protected by patent law.

Claims (10)

1. the spaces union supporting construction in a kind of rich water broken formation tunnel, it is characterized in that: including injection in country rock table in tunnel Face with a thickness of 3-5cm bonding layer concrete layer (1), be layed in the steel mesh (2) on bonding layer concrete layer (1) surface and interval is set The multiple steel arch-shelfs (3) set, the steel arch-shelf (3) touch with steel mesh (2) surface；The steel arch-shelf (3) and steel arch-shelf (3) it Between be arranged circumferentially longitudinally connected girder steel (4), axis of the longitudinally connected girder steel (4) along tunnel is staggered；The longitudinal direction Connection girder steel (4) is connected with the anchor pole (5) that anchoring section is located inside tunnel surrounding；Steel mesh (2) surface is injected with steel The steel fiber concrete layer (6) of arch (3), steel mesh (2) and longitudinally connected girder steel (4) covering, the steel fiber concrete layer (6) with a thickness of 20-25cm；The surface of the steel fiber reinforced concrete is equipped with waterproof/drainage structure layer (7)；The waterproof/drainage structure Layer (7) surface has poured two lining concrete layers (8).

2. the spaces union supporting construction in a kind of rich water broken formation tunnel according to claim 1, it is characterized in that: described The size of mesh opening of steel mesh (2) is 25cm.

3. the spaces union supporting construction in a kind of rich water broken formation tunnel according to claim 1, it is characterized in that: described The spacing of steel arch-shelf (3) is 50-70cm.

4. the spaces union supporting construction in a kind of rich water broken formation tunnel according to claim 1, it is characterized in that: described Longitudinally connected girder steel (4) is space lattice structure；The longitudinally connected girder steel (4) includes that epiplastron (9) and epiplastron (9) connect The lateral margin plate (11) connect and the bottom web (10) being connect with lateral margin plate (11)；The epiplastron (9) and bottom web (10), which are equipped with, to be used In the preformed hole (12) that anchor pole (5) performs；Two ends of the epiplastron (9) are equipped with bolt hole (13).

5. the spaces union supporting construction in a kind of rich water broken formation tunnel according to claim 1, it is characterized in that: described The length of anchor pole (5) is 3.0-3.5m；Spacing between the anchor pole (5) of the interlaced arrangement is not more than 1.2m.

6. the spaces union supporting construction in a kind of rich water broken formation tunnel according to claim 1, it is characterized in that: being located at The anchor pole of tunnel plenty water weak surrounding rock section is equipped with the multipoint displacement meter for detecting change in displacement in country rock body.

7. the spaces union supporting construction in a kind of rich water broken formation tunnel according to claim 1, it is characterized in that: described Waterproof/drainage structure layer (7) surface is equipped with multiple convex structures (15) and criss-cross diversion trench (16)；The waterproof/drainage structure The bottom end of layer (7) is connected with the drainpipe (17) positioned at tunnel bottom both ends.

8. a kind of method for protecting support of the spaces union supporting construction in rich water broken formation tunnel, it is characterized in that: the following steps are included:

1) bonding layer flexible support is performed, i.e., is the concrete that 3-5cm closes country rock in tunnel inner wall jet thickness；

2) steel mesh (2) are laid with, set up steel arch-shelf (3), size of mesh opening is layed in institute in step 1) for the steel mesh (2) of 25cm Then the concrete surface stated sets up the multiple steel arch-shelfs (3) touched with steel mesh (2) surface according to the spacing of 50-70cm；

3) two layers of rigid protection structure are performed, are arranged circumferentially by the spacing of design along tunnel axis between every two product steel arch-shelf (3) Then the longitudinally connected girder steel (4) that line is interspersed passes through bolt for the bracing members of longitudinally connected girder steel (4) and steel arch-shelf (3) Portion is overlapped position and is tentatively connected and fixed；

4) anchor pole (5) are performed, the anchor pole (5) being interspersed is performed on longitudinally connected girder steel (4), the anchoring section of anchor pole (5) is deep Entering in tunnel in country rock, the length of anchor pole (5) is 3.0-3.5m, and the spacing between anchor pole (5) is not more than 1.2m, meanwhile, it can be Multipoint displacement meter (14) are disposed on the anchor pole (5) of the typical paragraph of tunnel rich water broken formation, are displaced in country rock body with detecting Situation of change evaluates the loose range of country rock, for the perfect offer of anchor pole (5) supporting parameter in subsequent similar country rock paragraph construction Foundation；

5) steel fiber shotcrete makes to be formed between steel arch-shelf (3), longitudinally connected girder steel (4), anchor pole (5) and steel mesh (2) Stable spaces union support system improves the rigidity and bearing capacity of spaces union support system, and sprays steel fibre coagulation Soil thickness is not less than 20-25cm；

6) it is laid on the surface of the steel fiber reinforced concrete described in step 5) for the underground water for penetrating into bonding layer supporting to be discharged to The waterproof/drainage structure layer (7) of tunnel two sides gutter；

7) secondary lining is performed, the surface of the waterproof/drainage structure layer (7) described in step 6) pours two lining concrete, and pours Inverted arch forms closed supporting construction.

9. a kind of method for protecting support of the spaces union supporting construction in rich water broken formation tunnel according to claim 8, Be characterized in: longitudinally connected girder steel (4) described in step 3) is space lattice structure；The longitudinally connected girder steel (4) includes upper Web (9), bottom web (10) and lateral margin plate (11), the epiplastron (9) and bottom web (10) are reserved with and perform for anchor pole (5) Preformed hole (12)；The epiplastron (9) is reserved with bolt hole (13) close to the two sides of steel arch-shelf (3).

10. a kind of method for protecting support of the spaces union supporting construction in rich water broken formation tunnel according to claim 8, Be characterized in: waterproof/drainage structure layer (7) surface described in step 6) is equipped with convex structure (15) and criss-cross diversion trench (16)。