A support and reinforcement device and method for large deformation of soft rock in tunnels

Abstract

A tunnel soft rock large deformation support and reinforcement device and method, belonging to the technical field of tunnel construction. In the present invention, the tunnel soft rock large deformation support and reinforcement device includes four parts: an arch frame transverse connection device (1), an arch foot anchoring device (2), a steel arch frame (3), and a monitoring controller (4); the construction process includes: double-sided pilot tunnel excavation, installation of the arch foot anchoring device (2), installation and reinforcement of the steel arch frame (3), and other subsequent work. The steel arch frame (3) is installed in segments. After the soil in the corresponding two sides A areas in the tunnel is excavated step by step successively, the side wall steel arch frame (3.1) is installed; after the top B area is excavated, the arch crown steel arch frame (3.3) is installed, and after the corresponding C areas at the bottom and in the middle are excavated, the invert steel arch frame (3.2) is installed. All connections are made by welding.

Description

Technical Field

[0001] The present invention relates to a support and reinforcement device and method for large deformation of soft rock in tunnels, which is applicable to the construction of highway tunnels, railway tunnels and other tunnels in soft surrounding rock areas, and belongs to the technical field of tunnel construction. Background Art

[0002] Soft surrounding rock is surrounding rock with weak rock quality, low bearing capacity, serious weathering of rock mass and extrusion and fragmentation. Soft surrounding rock has the characteristics of low strength, poor stability, long continuous deformation time, short self-stabilization time and easy collapse.

[0003] Highway tunnels and railway tunnels are often built in mountainous areas, and the rock mass conditions in the mountainous areas where the tunnels pass through are difficult to determine. When encountering soft surrounding rock, mechanical excavation or blasting during tunnel construction may face the risk of collapse with a slight disturbance to the rock mass. In the construction of tunnels in soft surrounding rock areas, phenomena such as large deformation and collapse will occur, causing large deformation or even damage to the primary support structure of the tunnel.

[0004] Soft surrounding rock is easy to soften when encountering water, and the soil itself is relatively dense. It is difficult to construct and has a high engineering cost to reinforce soft surrounding rock by means of grouting. The construction method of grouting to reinforce surrounding rock is not applicable to the reinforcement excavation of soft surrounding rock.

[0005] After the arch support is used for tunnel excavation in soft surrounding rock areas, large deformations such as settlement and convergence will occur. The main reason is the lack of sufficient strength at the arch feet or insufficient stiffness of the arch. Therefore, anchoring the arch feet or strengthening the overall stiffness of the arch is an effective way to reduce the problem of large tunnel deformation. Summary of the Invention

[0006] The present invention relates to a support and reinforcement device and method for large deformation of soft rock in tunnels. The advantages of this method are that the construction process is simple and fast, it can effectively support the soft rock mass around the tunnel, and at the same time, it can conduct real-time dynamic monitoring on the stability support of the tunnel surrounding rock, timely discover unstable areas, and ensure the safety of personnel during the tunnel excavation process.

[0007] The support and reinforcement device for large deformation of soft rock in tunnels in the present invention includes four parts: an arch transverse connection device 1, an arch foot anchoring device 2, a steel arch 3, and a monitoring controller 4;

[0008] The steel arch 3 is divided into a side wall steel arch 3.1, an invert steel arch 3.2, a crown steel arch 3.3, and a waist steel arch 3.4; multiple invert steel arches 3.2 are arranged along the tunnel axis direction for support and reinforcement at the bottom of the tunnel, multiple side wall steel arches 3.1 are respectively arranged along the tunnel axis direction for support and reinforcement at the lower parts on both sides of the tunnel, multiple waist steel arches 3.4 are respectively arranged along the tunnel axis direction for support and reinforcement at the upper parts on both sides of the tunnel; multiple crown steel arches 3.3 are arranged along the tunnel axis direction for support and reinforcement at the top of the tunnel;

[0009] The arrangement of the sidewall steel arch frame 3.1, the arrangement of the invert steel arch frame 3.2, the arrangement of the crown steel arch frame 3.3, and the arrangement of the waist steel arch frame 3.4 are respectively fixedly connected by the arch frame transverse connection device 1; that is, the sidewall steel arch frame 3.1, the invert steel arch frame 3.2, the crown steel arch frame 3.3, and the waist steel arch frame 3.4 in the steel arch frame 3 are arranged in parallel along the tunnel axis direction, and the sidewall steel arch frame 3.1, the invert steel arch frame 3.2, the crown steel arch frame 3.3, or the waist steel arch frame 3.4 arranged in a row are fixedly connected by the arch frame transverse connection device 1;

[0010] Along the circumferential direction of the tunnel, the ends between the sidewall steel arch frame 3.1 and the waist steel arch frame 3.4 are connected by welding, and the ends between the arrangement of the crown steel arch frame 3.3 and the waist steel arch frame 3.4 are connected by welding; the sidewall steel arch frame 3.1 and the invert steel arch frame 3.2 are fixedly connected by the arch foot anchoring device 2;

[0011] The arch foot anchoring device 2 includes an H-shaped steel 2.1, a backing plate 2.2, and an anchoring pile 2.3; the length direction of the H-shaped steel 2.1 is along the tunnel axis direction; the lower end of the anchoring pile 2.3 is obliquely driven into the soil body, the length direction of the long strip-shaped backing plate 2.2 is along the tunnel axis direction, there are multiple anchoring piles 2.3 along the tunnel axis direction, and the long strip-shaped backing plate 2.2 is fixedly welded to the upper end surface of the anchoring pile 2.3; an H-shaped steel 2.1 following the length trend of the long strip-shaped backing plate 2.2 is fixedly welded on the long strip-shaped backing plate 2.2, the lower end notch of the H-shaped steel 2.1 is welded to the backing plate 2.2, the lower end of the sidewall steel arch frame 3.1 is inserted into the upper end notch of the H-shaped steel 2.1 for fixed welding, and the lower ends of the arch frame group composed of multiple sidewall steel arch frames 3.1 are fixedly welded in the upper end notch of the H-shaped steel 2.1; the outer side of one flange plate of the H-shaped steel 2.1 is fixedly welded to one end end face of the invert steel arch frame 3.2, and the end of one end of the arch frame group composed of multiple invert steel arch frames 3.2 is fixedly welded to the outer side of one flange plate of the H-shaped steel 2.1;

[0012] Among them, the arch frame transverse connection device 1 is a single-link structure, and the length direction of the single-link structure is along the tunnel axis direction and is used to firmly connect multiple sidewall steel arch frames 3.1, invert steel arch frames 3.2, crown steel arch frames 3.3, or waist steel arch frames 3.4 side by side to form a whole rigid structure; the arch frame transverse connection device 1 includes a long strip-shaped channel steel 1.1, an anchor 1.2, and an anchor rod 1.3;

[0013] Channel steel 1.1 Select the appropriate type of channel steel according to the softness of the surrounding rock and the cross-sectional size; Anchor 1.2 Use wedge-shaped anchors and select the appropriate type according to the need for applied pressure. It is used at the end of the anchor rod 1.3 to apply pressure from the anchor 1.2 to the channel steel 1.1; Anchor rod 1.3 Select the appropriate type and length according to the engineering design documents. When anchoring, it is inclined and driven into the soil body, and a certain pre-tension is applied, and it is anchored by the anchor 1.2. Apply pressure from the anchor 1.2 to the channel steel 1.1 to restrict the deformation of the channel steel 1.1 and the steel arch 3;

[0014] Channel steel 1.1 is the main body of the arch transverse connection device 1. The length direction of the channel steel 1.1 is consistent with the tunnel axis direction. At the position where the notch of the channel steel 1.1 corresponds to the connection of the steel arch 3, a bayonet 1.1.1 is provided. The size of the bayonet 1.1.1 is appropriately sized according to the type of the steel arch 3. The side of the steel arch 3 is embedded in the bayonet 1.1.1 and welded and fixed to facilitate restricting the deformation and displacement of the steel arch 3;

[0015] At the bottom surface of the groove of the channel steel 1.1, anchor holes 1.1.2 are provided at appropriate positions at intervals according to the designed arch spacing. The anchor holes 1.1.2 are opened with appropriate shapes and sizes according to the diameter of the anchor rod 1.3 and the size of the anchor 1.2. During construction, the anchor rod 1.3 passes through the anchor holes 1.1.2 and at the same time cooperates with the anchor 1.2 to extend into the soil body for construction to fix the channel steel 1.1 to the soil body.

[0016] The monitoring controller 4 includes an arch stress monitor 4.1, an anchor rod stress monitor 4.2, and an early warning device 4.3; The arch stress monitor 4.1 is installed on the channel steel 1.1; The anchor rod stress monitor 4.2 is installed between the anchor 1.2 and the channel steel 1.1; The arch stress monitor 4.1 and the anchor rod stress monitor 4.2 are respectively connected by circuit or signal to the early warning device 4.3.

[0017] The arch foot anchoring device 2 drives anchoring piles 2.3 on both sides of the arch foot and pins them with a backing plate 2.2, including an anchor H-shaped steel 2.1, a backing plate 2.2, and an anchoring pile 2.3; It mainly anchors the arch foot of the steel arch 3 and connects the arch foot positions of the steel arch 3 as a whole to jointly bear the force. At the same time, it also has the effect of strengthening the constraint strength of the arch foot and restricting the settlement and displacement of the steel arch 3.

[0018] The H-shaped steel 2.1 is used as an anchoring plate, and the appropriate size is selected according to the type of the steel arch 3 to ensure that the side wall steel arch 3.1 is placed in the groove of the H-shaped steel 2.1, and the cross-section of the invert steel arch 3.2 is in full contact with the flange plate of the H-shaped steel 2.1. The H-shaped steel 2.1 is connected to the steel arch 3 by welding to connect the arch foot positions of the entire steel arch 3 as a whole.

[0019] The backing plate 2.2 is made of a steel plate with a certain thickness, fixed at a suitable position on the H-shaped steel 2.1, and connected to the anchor pile 2.3 at the lower part. The connections between the backing plate 2.2 and the H-shaped steel 2.1 and the anchor pile 2.3 are both welded, which is used to anchor the corresponding positions between the H-shaped steel 2.1 and the anchor pile 2.3.

[0020] The anchor pile 2.3 is a steel pipe pile, the top of which is welded to the backing plate 2.2, and it is obliquely embedded in the soil at a certain inclination angle with the vertical direction, and interacts with the soil to generate a huge frictional force to prevent the settlement and displacement of the entire steel arch frame 3.

[0021] The main functions of the monitoring controller 4 are as follows: By monitoring the deformation and stress of the channel steel 1.1, the deformation of the steel arch frame 3 is monitored, and the deformation is controlled through reinforcement measures; by monitoring the pressure between the anchor 1.2 and the channel steel 1.1, the tension of the anchor bolt 1.3 is monitored. When the deformation of the steel arch frame 3 or the tension of the anchor bolt 1.3 exceeds the warning value, a warning is given in time to remind the workers to reinforce the dangerous area.

[0022] The arch frame stress monitor 4.1 is installed on the channel steel 1.1, and one arch frame stress monitor 4.1 is installed at intervals of a certain number of anchor bolts 1.3, which is used to monitor the stress exerted by the steel arch frame 3 on the channel steel 1.1, and at the same time, the deformation conditions of the steel arch frame 3 and the channel steel 1.1 can also be monitored. For the positions with larger deformation, a warning is given in time and reinforcement is carried out.

[0023] The anchor bolt stress monitor 4.2 is installed between the anchor 1.2 and the channel steel 1.1, and the monitoring and measurement of the anchor bolt stress is realized by detecting the pressure between the channel steel 1.1 and the anchor 1.2.

[0024] The warning device 4.3 is connected to the arch frame stress monitor 4.1 and the anchor bolt stress monitor 4.2 by wire or wirelessly. When the stress values detected by the arch frame stress monitor 4.1 and the anchor bolt stress monitor 4.2 exceed the warning value, the warning device 4.3 generates an alarm to remind to reinforce the dangerous area.

[0025] In the present invention, a stress arch frame stress monitoring device 4.1 and an anchor bolt stress monitoring device 4.1 are respectively installed on the channel steel 1.1 and the anchor bolt 1.3. The stress on the anchor bolt is collected and monitored in real time through the warning system, and a timely warning is given to the risk area, providing a reliable technical guarantee for the safe construction of the tunnel.

[0026] The present invention is applicable to various excavation methods of tunnels in soft surrounding rock areas. In the present invention, only the double-side drift method is used to introduce the application of the present invention in tunnel construction in combination with the specific content of the present invention.

[0027] The excavation section of the present invention is divided into four parts and excavated in four steps. The construction process includes: excavation of the double-sided pilot tunnels, installation of the arch-foot anchoring device 2, installation and reinforcement of the steel arch 3, and other subsequent works. The steel arch 3 is installed in segments. After the excavation of the soil masses in the corresponding two sides A1 and A2 areas in the tunnel, the side-wall steel arch 3.1 and the arch-waist steel arch 3.4 are installed respectively; after the excavation of the top B area is completed, the crown steel arch 3.3 is installed, and after the excavation of the corresponding C area at the bottom and in the middle is completed, the invert steel arch 3.2 is installed. All connections are made by welding.

[0028] The arch-frame transverse connection device 1 is applicable to the reinforcement connection of the steel arch 3 at various positions such as the crown, arch waist, side wall, and invert. For the crown steel arch 3.3 and the invert steel arch 3.2 in the areas where the rock mass is weak and prone to large deformation, the arch-frame transverse connection device 1 can be appropriately used for multiple reinforcements. For the surrounding rock area with large deformation after the construction is completed, the arch-frame transverse connection device 1 can still be used for secondary reinforcement.

[0029] Beneficial effects

[0030] The beneficial effects of the present invention are as follows:

[0031] (1) The arch-frame transverse connection device 1 can effectively reinforce the steel arch 3 in the tunnel in the weak surrounding rock area, ensuring the normal construction of the tunnel.

[0032] (2) The arch-foot anchoring device 2 adopts the anchoring pile 2.3. Through the friction between the anchoring pile 2.3 and the soil mass, the settlement and displacement of the arch feet of the steel arch 3 are effectively restricted. The H-shaped steel 2.1 is used to connect the arch feet of the steel arch 3 into a whole, improving the stiffness of the steel arch 3 and the overall mechanical properties of the support structure.

[0033] (3) The monitoring controller 4 monitors and gives early warnings in real time of the deformation of the weak surrounding rock of the tunnel. The deformation and stress of the channel steel 1.1 are monitored through the arch-frame stress monitor 4.1, so as to monitor the deformation of the steel arch 3; the pressure between the anchor fitting 1.2 and the channel steel 1.1 is monitored through the anchor rod stress monitor 4.2 to monitor the pressure of the anchor rod 1.3. When the deformation of the steel arch 3 or the tension of the anchor rod 1.3 exceeds the warning value, an early warning is given in time to remind to reinforce the dangerous area. Description of the drawings

[0034] Figure 1 Schematic diagram of the overall reinforcement of the steel arch;

[0035] Figure 2 Schematic diagram of the overall reinforcement of the tunnel section;

[0036] Figure 3 Schematic diagram of the arch-frame transverse reinforcement device;

[0037] Figure 4 Schematic diagram of the arch-frame bayonet connection;

[0038] Figure 5 Schematic diagram of the connection in the arch frame anchorage area;

[0039] Figure 6 Schematic diagram of the channel steel bayonet;

[0040] Figure 7 Schematic diagram of the anchor hole of the channel steel;

[0041] Figure 8 Schematic diagram of the arch foot reinforcement device;

[0042] Figure 9 Schematic diagram of the monitoring controller;

[0043] Figure 10 Schematic diagram of the excavation of the double-sided drift method for the tunnel.

[0044] Annotation of the attached drawings:

[0045] 1. Transverse connection device of the arch frame; 2. Arch foot anchorage device; 3. Steel arch frame; 4. Monitoring controller.

[0046] The transverse connection device 1 of the arch frame includes: 1.1 Channel steel; 1.2 Anchor; 1.3 Anchor rod.

[0047] The arch foot anchorage device 2 includes: 2.1 H-shaped steel; 2.2 Base plate; 2.3 Anchorage pile.

[0048] The steel arch frame 3 includes: 3.1 Side wall steel arch frame; 3.2 Inverted arch steel arch frame, 3.3 Crown steel arch frame, 3.4 Waist arch steel arch frame.

[0049] The monitoring controller 4 includes: 4.1 Arch frame stress monitor; 4.2 Anchor rod stress monitor; 4.3 Early warning device.

[0050] There are on the channel steel 1.1: 1.1.1 Bayonet and 1.1.2 Anchor hole.

[0051] A1, A2, B, and C at the tunnel section are all four different excavation areas. Specific implementation manner

[0052] The present invention can ensure the normal construction of the tunnel passing through the soft surrounding rock area, reduce the deformation and displacement of the steel arch frame 3 of the tunnel in the soft surrounding rock area, and provide a more stable support method for the tunnel construction in the soft surrounding rock area. The present invention installs the monitoring controller 4 and adopts the corresponding early warning system 4.3. When the soft surrounding rock of the tunnel becomes unstable and causes large deformation of the steel arch frame 3, the early warning system 4.3 alarms in time to remind the workers to reinforce the surrounding rock. The specific implementation manner of the present invention is introduced below in combination with the main inventive content of the device. Since the construction procedures of each cycle of tunnel excavation are the same, the specific implementation manner is introduced with the first construction cycle.

[0053] When the surrounding rock in front of the tunnel face is detected as soft rock through advanced geological prediction during tunnel construction, the construction shall be stopped. Select the appropriate device specifications of the present invention according to the geological conditions detected by the advanced prediction and the scale of the construction tunnel. The main items to be selected include: channel steel 1.1 of appropriate size, appropriate type and length of anchor rod 1.3, specifications of wedge-shaped anchor 1.2, size of H-shaped steel 2.1, size of backing plate 2.2, and diameter and length of anchor pile 2.3. At the same time, the angles of the anchor rod 1.3 and the anchor pile 2.3 should be reasonably designed.

[0054] 1. Excavation of double-sided pilot tunnels

[0055] First, excavate the pilot tunnels in areas A1 and A2 on the left and right sides respectively, and carry out step-by-step excavation with a certain distance staggered front and back. During excavation, it should be noted that the height of the excavation area of the pilot tunnels on both sides of the tunnel should not exceed the height of the arch waist (h), and select an appropriate cyclic excavation length L according to the surrounding rock conditions and the size of the tunnel section.

[0056] 2. Installation of the arch-foot anchoring device 2

[0057] The anchor pile 2.3 uses a steel pipe pile, which is embedded in the soil to generate sufficient friction with the soil. When the soil in area A is excavated to the appropriate position respectively, the position of the anchor pile 2.3 can be lofted and marked.

[0058] Using an appropriate pile-driving machine, embed the anchor pile 2.3 into the soil according to the previously designed angle of the anchor pile 2.3. For anchor piles 2.3 with a greater depth, they can be embedded in sections, and sufficient welding strength must be ensured between each section.

[0059] After the anchor pile 2.3 is embedded to the appropriate depth determined by calculation, weld the backing plate 2.2 to the top of the anchor pile 2.3, and then continue to use the machine to completely embed the anchor pile 2.3 into the soil, and control the backing plate 2.2 to the appropriate horizontal position to keep the arch feet on the same horizontal line.

[0060] After installing an appropriate number of anchor piles 2.3, place the H-shaped steel 2.1 on the backing plate 2.2, and connect the H-shaped steel 2.1 and the backing plate 2.2 by welding. Install the remaining anchor piles 2.1, backing plates 2.2 and H-shaped steels 2.1 in this cycle. The H-shaped steels 2.1 must be connected by welding and must have sufficient welding strength.

[0061] 3. Installation and reinforcement of the steel arch 3

[0062] Step 1: After the installation of the springing anchorage device 2 is completed, install the sidewall steel arch 3.1. When installing the sidewall steel arch 3.1, install the bottom of the sidewall steel arch 3.1 in the groove of the H-shaped steel 2.1. Constrained by the flange plate of the H-shaped steel 2.1, it can resist the horizontal pressure from the surrounding rock on the sidewall steel arch 3.1. The sidewall steel arch 3.1 and the web of the H-shaped steel 2.1 are connected by welding, and ensure the firmness of the welding during connection.

[0063] Step 2: After a certain number of sidewall steel arches 3.1 are installed, use machinery to cooperate to clamp the sidewall steel arch 3.1 with the bayonet 1.1.1 of the channel steel 1.1. The size and position requirements of the bayonet 1.1.1 of the channel steel 1.1 match the steel arch 3. After the bayonet 1.1.1 of the channel steel 1.1 corresponds to the sidewall steel arch 3.1, weld the sidewall steel arch 3.1 at the bayonet 1.1.1 to the bayonet 1.1.1 of the channel steel 1.1. On the one hand, it is required to fix the position of the channel steel 1.1 on the sidewall steel arch 3.1, and at the same time, ensure the connection strength between the channel steel 1.1 and the steel arch 3.

[0064] Step 3: After the channel steel 1.1 is fixed, apply stress to the bolt 1.3 in time to anchor the structure. Pass through the anchor hole 1.1.2 of the channel steel 1.1, and drill a hole in the tunnel surrounding rock at a certain angle α. Insert the bolt 1.3 into the tunnel surrounding rock through the anchor hole 1.1.2, and fill the pores with cement mortar. After the bolt 1.3 is applied and the cement mortar reaches a certain strength, use the anchor 1.2 to tightly anchor the channel steel 1.1, and apply a certain pre-tension to the bolt 1.2. Apply the arch stress monitor 4.1 at a suitable position on the channel steel 1.1, and connect it to the early warning system 4.3 with a wire. When the pressure on the steel arch 3 increases due to the weakness of the rock mass, the deformation of the channel steel 1.1 increases accordingly. When the deformation of the channel steel 1.1 reaches a certain degree, the arch stress monitor 4.1 triggers the early warning system 4.3 to remind to reinforce the deformed area in time.

[0065] Install the waist steel arch 3.4 and the steel arch transverse reinforcement device 1 in the same way.

[0066] Step 4: After the installation of the sidewall steel arch 3.1 for one cycle is completed, excavate the soil in area B. When excavating the soil in area B, when the upper soil is excavated to an appropriate distance, use machinery to cooperate to install the waist steel arch 3.4. When installing the waist steel arch 3.4, use relevant machinery to lift and fix the arch to the predetermined position, and complete the connection between the sidewall steel arch 3.1 and the waist steel arch 3.4 by welding at the joint, and ensure the welding strength. After connection, connect and anchor the waist steel arch 3.4 in the same way with the arch transverse connection device 1. Follow the excavation of the soil in area B to complete the installation of the waist steel arch 3.4 in sequence.

[0067] Step 5: After a certain number of the waist arch steel frames 3.4 are installed, the mechanical equipment is used to install the crown arch steel frame 3.3. The connection between the crown arch steel frame 3.3 and the waist arch steel frame 3.4 is completed by welding at the joints on both sides, and the welding strength is ensured. After the connection, the arch frame transverse connection device 1 is used to connect and anchor the crown arch steel frame 3.3 in the same way.

[0068] Step 6: After the installation of the side wall arch steel frames 3.1, the waist arch steel frames 3.4 and the crown arch steel frames 3.3 in one cycle are completed, the soil body in area C of the tunnel can be excavated. After excavating an appropriate length of the soil body in area C, the invert arch steel frame 3.2 can be installed. The two sides of the invert arch steel frame 3.2 are connected to the flange plates of the H-shaped steel 3.1, and the two sides of the invert arch steel frame 3.2 are connected to the rigid hinge 2 by welding, and the welding strength is ensured during the connection.

[0069] Step 7: After a certain number of the invert arch steel frames 3.2 are installed, the mechanical equipment is used to install the arch frame transverse reinforcement device 1, and the invert arch steel frame 3.2 is connected and anchored in the same way.

[0070] The spacing of the arch frame transverse reinforcement device 1 is appropriately reduced at the welded parts between the steel frames 3.

[0071] The above construction sequence is arranged as follows: After the completion of the third step of the installation and reinforcement of the steel frame 3 in the previous cycle, the double-side drift excavation of the next cycle can be carried out.

[0072] The present invention can connect the steel frames 3 of the soft surrounding rock tunnel, enhance the overall stiffness and anti-deformation ability, and ensure the safety of tunnel construction. The arch frame transverse connection device 1 connects the steel frames 3 to form a whole to bear force, effectively increasing the ability of the steel frame 3 to resist external forces. The arch foot anchoring device 2 strengthens the constraint strength at the arch feet of the steel frame 3, and sufficiently controls the settlement and displacement of the steel frame 3. During the construction process, the monitoring controller 4 can realize the real-time monitoring of the deformation of the soft surrounding rock of the tunnel and the tension of the anchor bolt 1.3. When the strength of the soft surrounding rock during tunnel construction decreases and a collapse is about to occur, causing the deformation of the channel steel 1.1, the monitoring controller 4 can realize risk prediction and remind to reinforce the risk area in time to prevent accidents.

[0073] The present invention includes but is not limited to the above content.

Claims

1. Support and reinforcement device for large deformation of soft rock in tunnels, characterized in that, It includes four parts: the transverse connection device of the steel arch, the arch foot anchoring device, the steel arch, and the monitoring controller; The steel arch is divided into sidewall steel arches, invert steel arches, crown steel arches, and waist steel arches; multiple invert steel arches are arranged along the tunnel length direction for support and reinforcement at the bottom of the tunnel, multiple sidewall steel arches are respectively arranged along the tunnel length direction for support and reinforcement at the lower parts on both sides of the tunnel, multiple waist steel arches are respectively arranged along the tunnel length direction for support and reinforcement at the upper parts on both sides of the tunnel; multiple crown steel arches are arranged along the tunnel length direction for support and reinforcement at the top of the tunnel; The arrangements of sidewall steel arches, invert steel arches, crown steel arches, and waist steel arches are all fixedly connected by the transverse connection device of the steel arch; that is, the sidewall steel arches, invert steel arches, crown steel arches, and waist steel arches in the steel arch are arranged in parallel along the tunnel length direction, and the sidewall steel arches, invert steel arches, crown steel arches, and waist steel arches arranged in a row are all fixedly connected by the transverse connection device of the steel arch; Along the circumferential direction of the tunnel, the ends between the sidewall steel arches and the waist steel arches are connected by welding, and the ends between the crown steel arches and the waist steel arches are connected by welding; the sidewall steel arches and the invert steel arches are fixedly connected by the arch foot anchoring device; The arch foot anchoring device includes an H-shaped steel, a long strip-shaped backing plate, and an anchoring pile; the length direction of the H-shaped steel is along the tunnel length direction; the lower end of the anchoring pile is obliquely inserted into the soil, the length direction of the long strip-shaped backing plate is along the tunnel length direction, multiple anchoring piles are arranged along the tunnel length direction, and the long strip-shaped backing plate is fixedly welded to the upper end face of the anchoring pile; an H-shaped steel following the length trend of the long strip-shaped backing plate is fixedly welded on the long strip-shaped backing plate, the lower end notch of the H-shaped steel is welded to the long strip-shaped backing plate, the lower end of the sidewall steel arch is inserted into the upper end notch of the H-shaped steel for fixed welding, and the lower ends of the arrangements composed of multiple sidewall steel arches are all fixedly welded in the upper end notch of the H-shaped steel; the outer side flange of the H-shaped steel is fixedly welded to one end face of the invert steel arch, and the end of one end of the arrangement composed of multiple invert steel arches is fixedly welded to the outer side flange of the H-shaped steel; Among them, the transverse connection device of the steel arch is a single-link structure, and the length direction of the single-link structure is along the tunnel length direction, which is used to firmly connect multiple sidewall steel arches, invert steel arches, crown steel arches, and waist steel arches side by side to form a whole rigid structure; The transverse connection device of the steel arch includes a long strip-shaped channel steel, an anchor, and a bolt; The anchor is a wedge anchor, which is used at the end of the bolt to apply pressure from the anchor to the channel steel; the channel steel is the main body of the transverse connection device of the steel arch, and the length direction of the channel steel is consistent with the tunnel length direction. A clamping notch is set at the position corresponding to the connection of the channel steel notch and the steel arch, and the side of the steel arch is embedded into the clamping notch and welded for fixation to facilitate restricting the deformation and position of the steel arch; At the bottom of the channel steel groove, anchor holes are set at intervals according to the designed steel arch spacing. The anchor holes are opened in shapes and sizes according to the diameter of the bolt and the size of the anchor. During construction, the bolt passes through the anchor hole and cooperates with the anchor to extend into the soil for construction to fix the channel steel to the soil; The monitoring controller includes an arch stress monitor, a bolt stress monitor, and a warning device. The arch stress monitor is installed on the channel steel; the bolt stress monitor is installed between the anchor and the channel steel; for detecting the distribution of the arch stress monitor and the bolt stress monitor and connecting to the warning device. The H-shaped steel is used as an anchor plate, and the size is selected according to the model of the steel arch frame to ensure that the side wall steel arch frame is placed in the groove of the H-shaped steel, and the cross-section of the invert steel arch frame is in full contact with the flange plate of the H-shaped steel; the H-shaped steel and the steel arch frame are connected by welding, which is used to connect the arch feet of the entire steel arch frame into a whole. The long strip-shaped cushion plate is made of steel plate with a certain thickness, fixed on the H-shaped steel, and connected to the anchor pile at the lower part. The connections between the long strip-shaped cushion plate and the H-shaped steel and the anchor pile are both welded, which is used to anchor the relative positions of the H-shaped steel and the anchor pile to realize their fixation and connection.

2. The tunnel soft rock large deformation support and reinforcement device according to claim 1, characterized in that, The anchor pile is a steel pipe pile, welded to the long strip-shaped cushion plate at the top, embedded in the soil at an inclined angle with the vertical direction, and generates a huge frictional force with the soil to prevent the settlement and displacement of the entire steel arch frame.

3. The tunnel soft rock large deformation support and reinforcement device according to claim 1, characterized in that, The main functions of the monitoring controller are: by monitoring the deformation and stress of the channel steel, the deformation of the steel arch frame is monitored, and the deformation is controlled through reinforcement measures; by monitoring the pressure between the anchor and the channel steel, the tension of the bolt is monitored. When the deformation of the steel arch frame or the tension of the bolt exceeds the warning value, a warning is given in time to remind the workers to reinforce the dangerous area.

4. The tunnel soft rock large deformation support and reinforcement device according to claim 1, characterized in that, The arch stress monitor is installed on the channel steel, and an arch stress monitor is installed at intervals of a certain number of bolts, which is used to monitor the stress exerted by the steel arch frame on the channel steel, and at the same time can also monitor the deformation of the steel arch frame and the channel steel; timely warning and reinforcement are given to the positions with large deformation.

5. The tunnel soft rock large deformation support and reinforcement device according to claim 1, characterized in that, The bolt stress monitor is installed between the anchor and the channel steel, and the stress of the bolt is monitored and measured by detecting the pressure between the channel steel and the anchor.

6. The tunnel soft rock large deformation support and reinforcement device according to claim 1, wherein The warning device is connected to the arch stress monitor and the bolt stress monitor by wire or wirelessly. When the stress values detected by the arch stress monitor and the bolt stress monitor exceed the warning value, the warning device generates an alarm to remind to reinforce the dangerous area. The arch stress monitor and the bolt stress monitor are respectively installed on the channel steel and the bolt. The stress received by the bolt is collected and monitored in real time through the warning system, and the risk area is warned in time to provide a reliable technical guarantee for the safe construction of the tunnel.

7. The tunnel soft rock large deformation support and reinforcement device according to claim 1, characterized in that, The tunnel excavation section is divided into 4 parts and excavated in 4 steps; the construction process includes: excavation of the double-sided pilot tunnels, installation of the arch foot anchoring device, installation and reinforcement of the steel arch frame; the steel arch frame is installed in segments, and the side wall steel arch frame and the arch waist steel arch frame are installed after the excavation of the corresponding two sides A1 and A2 areas in the tunnel; the arch crown steel arch frame is installed after the excavation of the top B area, and the invert steel arch frame is installed after the excavation of the corresponding C area at the bottom and in the middle.

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