A grouting reinforcement device for a shield tunnel in a broken zone formation and its grouting reinforcement method

Abstract

The present invention relates to a shield tunnel broken zone stratum grouting reinforcement equipment and a grouting reinforcement method thereof, characterized in that the grouting reinforcement equipment comprises: a shield segment, a grouting pump, a slurry storage tank and a grouting tool; the shield segment is installed inside the tunnel, and the inner surface of the shield segment is provided with a pre-buried grouting hole; the grouting pump and the slurry storage tank are arranged on the inner side of the shield segment, and the grouting pump is connected with the slurry storage tank through a conveying pipeline; the slurry storage tank comprises an agitator and a slurry storage tank body; the grouting tool passes through the pre-buried grouting hole, the back area of ​​the shield segment and the deep grouting area in sequence, and the grouting tool comprises a grouting pipe, a pipe-valve connector, a thread and a gate valve; the grouting reinforcement method of the present invention is simple to operate, easy to implement, and can perform layered grouting reinforcement on the broken zone stratum in the tunnel, thereby improving the tunnel operation safety and the stratum stability and strength.

Description

Technical Field

[0001] The present invention relates to the technical field of tunnel construction, and more particularly, to a grouting reinforcement device for a shield tunnel in a broken zone stratum and a grouting reinforcement method therefor. Background Art

[0002] In recent years, with the rapid development of society, there has been an increasing amount of rail transit construction in cities. The shield method has been widely used in the construction of urban rail transit sections due to its fast construction speed and little impact on the ground. During the construction in some river cities, after the shield machine passes through, groundwater seeps along the broken zone stratum and soaks the moderately weathered argillaceous siltstone around the tunnel, resulting in the softening, disintegration and fragmentation of the rock stratum, which affects the operation safety of the tunnel.

[0003] The existing treatment method is to use the synchronous grouting system of the shield machine to fill the cavity behind the segment. Since the grouting volume behind the segment is limited, according to the relationship between the excavation diameter of the shield machine and the outer diameter of the segment, the thickness of the filled cavity is generally only 15 cm, and it is impossible to reinforce the stratum behind the segment in the broken zone area, and no effective safety guarantee and solution can be provided for the tunnel operation.

[0004] For example, the invention patent with the Chinese patent publication number CN110486049A discloses a comprehensive treatment method for a water-rich sandstone roadway passing through a fault broken zone. The comprehensive treatment method for the water-rich sandstone roadway passing through the fault broken zone includes the following steps: water diversion and pressure relief, wall breaking and grouting, advanced pre-grouting, and water exploration holes. By diverting water and relieving pressure and wall breaking and grouting, the scattered water and dripping water in the roadway are introduced into the drainage pipeline, effectively improving the appearance of the roadway; by constructing a "grout-stop rock cap", the slurry leakage from the cracks at the heading can be effectively prevented, making the grouting effect better; through advanced pre-grouting, the rock cracks can be effectively reinforced, and large water inrusions can be avoided during the tunneling process within the grouting control range, the rock mechanical properties of the roadway can be well reinforced, the surrounding rock strength can be increased, the safety during the construction process can be ensured, the surrounding rock of the roadway can be effectively reinforced, the cracks can be filled, the stability of the surrounding rock can be increased, the water inflow can be reduced, and the construction safety can be ensured.

[0005] Another example is the invention patent with Chinese patent publication number CN110259465A, which discloses a method for single shield dual-mode TBM pre-grouting reinforcement of fault fracture zone, including the steps of installing pre-drilling equipment on the rotating disk of the TBM assembly machine; pre-drilling through at least one of the eight horizontal holes and fourteen oblique holes of the TBM; pre-grouting according to the drilling conditions; and grouting reinforcement and hole sealing. Grouting reinforcement can be quickly performed on the face fracture zone, and grouting reinforcement can be performed on the previous hole when drilling the next hole, which greatly saves construction time, saves manpower, and has high construction efficiency. In mechanical construction, the use of matching grouting reinforcement equipment can greatly reduce the time for equipment cycle installation and commissioning, improve construction efficiency, and can achieve maximum reinforcement of the fault fracture zone soil under the reserved holes of the equipment, which is worthy of promotion in EPB and TBM tunnel excavation fault fracture zones. Summary of the invention

[0006] The purpose of the present invention is to provide a shield tunnel broken zone stratum grouting reinforcement equipment and a grouting reinforcement method thereof in view of the deficiencies of the prior art.

[0007] A shield tunnel broken zone stratum grouting reinforcement equipment, the grouting reinforcement equipment comprising: a shield segment, a grouting pump, a grouting tank and a grouting tool;

[0008] The shield segment is installed inside the tunnel, the inner surface of the shield segment is provided with a pre-buried grouting hole, and the outer side of the shield segment is provided with a shield segment back area and a deep grouting area in sequence;

[0009] The grouting pump and the slurry storage tank are arranged on the inner side of the shield segment, and the grouting pump is connected with the slurry storage tank through a conveying pipeline;

[0010] The slurry storage tank comprises a slurry storage tank body and a stirrer. The injection port of the slurry storage tank body is connected to the cement slurry delivery pipe and the water glass delivery pipe respectively through a Y-shaped pipe. The stirrer is arranged in the slurry storage tank body to stir the mixed slurry injected into the slurry storage tank body.

[0011] The grouting tool sequentially passes through the embedded grouting holes, the back region of the shield segment, and the deep grouting region. The grouting tool includes a grouting pipe, a pipe valve connector, a screw thread, and a gate valve. The pipe valve connector is located inside the shield segment and is connected to the shield segment through the screw thread. Limiting grooves and positioning protrusions are respectively arranged at both ends of the pipe valve connector. The grouting pipe is composed of a first grouting pipe and a second grouting pipe. The first grouting pipe is sequentially arranged through the shield segment and the back region of the shield segment. A fixed groove is arranged on the left side of the first grouting pipe. The left side of the first grouting pipe and the right side of the pipe valve connector are inserted and fixed through the positioning protrusion and the fixed groove. The second grouting pipe penetrates through the deep grouting region. The gate valve is arranged in the limiting groove on the left side of the pipe valve connector.

[0012] Further, 16 of the embedded grouting holes are provided on the shield segment.

[0013] Further, one gate valve is correspondingly installed for each of the embedded grouting holes.

[0014] Further, plum blossom-shaped holes are arranged on the side surface of the second grouting pipe, and the distance between the plum blossom-shaped holes is 200 mm.

[0015] The present invention further provides a method for grouting and reinforcing a broken zone formation in a shield tunnel. The grouting and reinforcing method includes the following steps:

[0016] Step 1, use a shield segment crane to lift 6 shield segments into the tunnel and assemble the shield segments in the tunnel:

[0017] Step 1.1, assemble 6 shield segments by using the staggered joint assembly method, and then symmetrically install the remaining 1 shield segment from bottom to top and left to right. Connect and fix each shield segment through circumferential bolts and longitudinal bolts.

[0018] Step 1.2, after installing the entire ring of shield segments, use a pneumatic wrench to fix all bolts and plug the lifting holes.

[0019] Step 2, open embedded grouting holes on the shield segments and install the grouting tool in the embedded grouting holes:

[0020] Step 2.1, the embedded grouting holes are evenly arranged on each ring of shield segments. Drill through the drill to the cavity part in the back region of the shield segment, and clean the slag water in the cavity part.

[0021] Step 2.2, sequentially install the grouting pipe and the pipe valve connector into the embedded grouting holes, then install the gate valve in the limiting groove, and expose the gate valve on the surface of the shield segment.

[0022] Step 3, prepare the slurry to be injected into the embedded grouting holes in the mixing plant:

[0023] Step 3.1, in the mixing plant, prepare single slurry according to the water-cement weight ratio of 1:1 for the cement slurry, and prepare the cement slurry and water glass mixed slurry according to the volume ratio of 1:1 between the cement slurry and water glass;

[0024] Step 3.2, transport the single slurry to the slurry storage tank through the grouting pipeline. After the single slurry is transported to the slurry storage tank body, start the agitator to uniformly stir the single slurry for 5 - 10 minutes to prevent the slurry of the single slurry from coagulating or segregating;

[0025] Step 3.3, connect the grouting pipeline with the gate valve, and open the gate valve. Inject the single slurry into the area on the back of the shield segment around the embedded grouting hole through the grouting pump to form a water-stop curtain;

[0026] Step 3.4, during the process of filling the single slurry into the cavity part, control the injection speed and injection volume of the single slurry through the gate valve. The injection flow rate of the single slurry is 2m 3 / min;

[0027] Step 3.5, through the pressure sensor set on the grouting pipeline, monitor the grouting volume and grouting pressure of each ring of shield segment, and control the grouting pressure of the grouting pump at 0.2 - 1 MPa;

[0028] Step 3.6, after the single slurry fills the cavity part and forms a water-stop curtain, remove the grouting tool and use an acoustic wave monitor to detect the grouting density of the cavity part;

[0029] Step 3.7, detect the grouting density of the cavity part through the acoustic wave monitor, so that the grouting density is not less than 1220 kg / m 3 , if the specified grouting density is not reached, return to Step 3.3 and continue to execute the following steps;

[0030] Step 4, after the slurry in the area on the back of the shield segment solidifies, continue to open the embedded grouting hole deeper:

[0031] Step 4.1, use a drill to open the embedded grouting hole, with the opening depth of drilling 3 m in the direction of the outside of the shield segment, and install the grouting tool in the embedded grouting hole;

[0032] Step 4.2, during the process of installing the grouting tool in the embedded grouting hole, ensure that the second grouting pipe is inserted to the bottom of the embedded grouting hole, and connect the grouting pump with the grouting tool through the grouting pipeline;

[0033] Step 5, inject the mixed slurry into the deep grouting area:

[0034] Step 5.1, start the double-fluid grouting machine and the gate valve to inject the mixed slurry into the deep grouting area;

[0035] In Step 5.2, during the process of filling the mixed slurry into the deep grouting area, the injection speed and injection volume of the mixed slurry are controlled by a gate valve. The injection flow rate of the mixed slurry is 1.5 m 3 / min;

[0036] In Step 5.3, monitor the grouting volume and grouting pressure of each ring of shield segments, and control the grouting pressure of the grouting pump at 0.2 - 0.4 Mpa;

[0037] In Step 5.4, add an appropriate amount of bentonite to the mixed slurry to promote the flow of the mixed slurry and adjust the grouting pressure;

[0038] In Step 6, use an acoustic monitor to check the grouting effect, and use cement to seal the pre-buried grouting holes to complete the reinforcement operation of the formation by grouting.

[0039] Furthermore, in Step 3.2, the cement in the single-component slurry uses Portland cement above grade 42.5, and the water-cement ratio is 1.5:1, 1:1, 0.75:1.

[0040] Furthermore, in Step 3.3, connect the grouting pipeline to the gate valve 4.4, open the gate valve 4.4, and inject the single-component slurry into the area on the back of the shield segments around the pre-buried grouting holes 1.1 through the grouting pump 2. Specifically, it includes:

[0041] In Step 3.3.1, first pump a predetermined amount of thick cement slurry with a water-cement ratio of 0.75:1 into the area on the back of the shield segments around the pre-buried grouting holes. After the cement slurry is initially stable, conduct secondary grouting;

[0042] In Step 3.3.2, then pump a predetermined amount of standard cement slurry with a water-cement ratio of 1:1 into the area on the back of the shield segments around the pre-buried grouting holes. After the cement slurry is stable, conduct tertiary grouting;

[0043] In Step 3.3.3, finally pump a predetermined amount of thin cement slurry with a water-cement ratio of 1.5:1 into the area on the back of the shield segments around the pre-buried grouting holes. After the cement slurry is stable, seal the holes.

[0044] Furthermore, during the process of injecting the single-component slurry into the area on the back of the shield segments around the pre-buried grouting holes in Step 3.3, add an early strength agent to improve the early strength of the slurry. The early strength agent is composed of lithium sulfate, polycarboxylate water reducer, and air-entraining agent. Among them, the weight percentages of each component are: lithium sulfate 65%, polycarboxylate water reducer 30%, and sodium dodecylbenzenesulfonate 5%.

[0045] Furthermore, in Step 5, the water glass in the mixed slurry has a modulus of 2.4 - 2.8 and a concentration of 30 - 45°Be.

[0046] Further, before step 5 of starting the double-fluid grouting machine and the gate valve to inject the mixed grout into the deep grouting area, it includes: secondary stirring of the mixed grout in the slurry storage tank to prevent precipitation and segregation of the mixed grout and avoid pipe blockage in the pipeline.

[0047] Compared with the prior art, the present invention has the following remarkable advantages:

[0048] 1. In the grouting reinforcement equipment of the present invention, the grouting pipe and the pipe valve connector are fixedly connected by screw threads, the pipe valve connector and the shield segment are connected by screw threads, and the gate valve is installed on one side of the pipe valve connector, which is convenient for disassembly and reuse and prevents affecting the tunnel clearance.

[0049] 2. In the grouting reinforcement method of the present invention, through the process combination of single-fluid grouting in the area behind the segment around the pre-embedded grouting hole and mixed grouting in the deep grouting area, it effectively prevents the deep grouting slurry from running or leaking along the back of the segment and strengthens the construction quality of deep grouting.

[0050] 3. The grouting reinforcement method of the present invention is simple to operate, easy to implement, grouts the broken zone formation in the tunnel, improves the operation safety of the tunnel, and enhances the formation stability and strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] Figure 1 is a schematic structural diagram of the grouting reinforcement equipment of the present invention;

[0052] Figure 2 is Figure 1 a schematic diagram of grouting in the area behind the shield segment in

[0053] Figure 3 is a schematic structural diagram of the grouting tool in the grouting reinforcement equipment of the present invention;

[0054] Figure 4 is Figure 3 a partial enlarged schematic diagram of part A in

[0055] Figure 5 is a flowchart of the grouting reinforcement method of the present invention.

[0056] DESCRIPTION OF THE REFERENCE NUMERALS:

[0057] 1 - shield segment, 1.1 - pre-embedded grouting hole; 2 - grouting pump; 3 - slurry storage tank, 3.1 - slurry storage tank body, 3.2 - stirrer; 4 - grouting tool, 4.1 - grouting pipe, 4.2 - pipe valve connector, 4.3 - screw thread, 4.4 - gate valve, 4.1.1 - first grouting pipe, 4.1.2 - second grouting pipe, 4.2.1 - limit groove, 4.2.2 - positioning protrusion, 4.1.2.1 - plum blossom-shaped hole; 5 - area behind the shield segment; 6 - deep grouting area. DETAILED DESCRIPTION

[0058] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0059] The present invention provides a shield tunnel broken zone stratum grouting reinforcement equipment, the grouting reinforcement equipment comprises: a shield segment 1, a grouting pump 2, a grouting tank 3 and a grouting tool 4.

[0060] like Figure 1 As shown, the shield segment 1 is installed inside the tunnel, and the inner surface of the shield segment 1 is provided with pre-buried grouting holes 1.1, which are evenly arranged along the circumference of the shield segment 1. A grouting pump 2 and a slurry storage tank 3 are arranged on the inner side of the shield segment 1. The grouting pump 2 and the slurry storage tank 3 are connected through a conveying pipeline. The slurry storage tank 3 includes a slurry storage tank body 3.1 and an agitator 3.2. The injection port of the slurry storage tank body 3.1 is connected to a cement slurry conveying pipe and a water glass conveying pipe (not shown in the figure) through a Y-shaped pipe. The agitator 3.2 is arranged in the slurry storage tank body 3.1 to stir the mixed slurry injected into the slurry storage tank body 3.1. The outer side of the shield segment 1 is sequentially provided with a shield segment back area 5 and a deep grouting area 6, as shown in FIG. Figure 1 and Figure 3 As shown, the grouting tool 4 passes through the pre-buried grouting hole 1.1, the back area 5 of the shield segment and the deep grouting area 6 in sequence. The grouting tool 4 includes a grouting pipe 4.1, a pipe-valve connector 4.2, a thread 4.3 and a gate valve 4.4. The pipe-valve connector 4.2 is located in the shield segment 1. The pipe-valve connector 4.2 is connected to the shield segment 1 through the thread 4.3. The two ends of the pipe-valve connector 4.2 are respectively provided with a limited groove 4.2.1 and a positioning protrusion 4.2.2. The grouting pipe 4.1 consists of a first grouting pipe 4.1.1 and a second The invention relates to a grouting pipe 4.1.2, wherein the first grouting pipe 4.1.1 is sequentially arranged in the shield segment 1 and the back area 5 of the shield segment, a fixing groove (not shown in the figure) is arranged on the left side of the first grouting pipe 4.1.1, the left side of the first grouting pipe 4.1.1 is fixed to the right side of the pipe valve connector 4.2 by means of a positioning protrusion 4.2.2 and a fixing groove, the second grouting pipe 4.1.2 is arranged in the deep grouting area 6, and the gate valve 4.4 is arranged in the limiting groove 4.2.1 on the left side of the pipe valve connector 4.2.

[0061] Further, such as Figure 2 As shown, 16 pre-buried grouting holes 1.1 are provided on the shield segment 1.

[0062] Further, such as Figure 3 As shown, each pre-buried grouting hole 1.1 is correspondingly installed with a gate valve 4.4.

[0063] Further, such asFigure 3 As shown, plum blossom-shaped holes 4.1.2.1 are arranged on the side of the second grouting pipe 4.1.2, and the distance between the plum blossom-shaped holes 4.1.2.1 is 200 mm.

[0064] The present invention further provides a method for grouting and strengthening the strata in the broken zone of a shield tunnel. The grouting and strengthening method includes the following steps:

[0065] Step 1: Use a shield segment crane to lift 6 shield segments 1 into the tunnel and assemble the shield segments 1 in the tunnel:

[0066] Step 1.1: Assemble 6 shield segments 1 using the staggered joint assembly method, and then symmetrically install the remaining 1 shield segment 1 from bottom to top and left and right. Connect and fix each shield segment 1 with circumferential bolts and longitudinal bolts;

[0067] Step 1.2: After installing the entire ring of shield segments 1, use a pneumatic wrench to fix all bolts and plug the lifting holes;

[0068] Step 2: Open embedded grouting holes 1.1 on the shield segments 1 and install grouting tools 4 in the embedded grouting holes 1.1:

[0069] Step 2.1: The embedded grouting holes 1.1 are evenly arranged on each ring of shield segments 1. Drill through the shield segments 1 to the cavity part of the back area 5 using a drill, and clean the slag water in the cavity part;

[0070] Step 2.2: Install the grouting pipe 4.1 and the pipe valve connector 4.2 into the embedded grouting holes 1.1 in sequence, then install the gate valve 4.4 in the limit groove 4.2.1, and make the gate valve 4.4 exposed on the surface of the shield segments 1;

[0071] Step 3: Prepare the slurry to be injected into the embedded grouting holes 1.1 in the mixing station:

[0072] Step 3.1: In the mixing station, prepare single slurry according to the water-cement weight ratio of 1:1 for cement slurry, and prepare a cement slurry and water glass mixed slurry according to the volume ratio of 1:1 for cement slurry and water glass;

[0073] Step 3.2: Transport the single slurry to the slurry storage tank 3 through the grouting pipeline. After the single slurry is transported to the slurry storage tank body 3.1, start the agitator 3.2 to evenly stir the single slurry, and the stirring time is 5 - 10 minutes to prevent the slurry of the single slurry from coagulating or separating;

[0074] Step 3.3: Connect the grouting pipeline with the gate valve 4.4, open the gate valve 4.4, and inject the single slurry into the back area 5 of the shield segments around the embedded grouting holes 1.1 through the grouting pump 2 to form a water-stop curtain;

[0075] Step 3.4, during the process of filling the single slurry into the cavity part, control the injection speed and injection volume of the single slurry through the gate valve 4.4. The injection flow rate of the single slurry is 2 m 3 / min;

[0076] Step 3.5, through the pressure sensor set on the grouting pipeline, monitor the grouting volume and grouting pressure of each ring of shield segment 1, and control the grouting pressure of the grouting pump 2 at 0.2 - 1 MPa;

[0077] Step 3.6, after the single slurry fills the cavity part and forms a water-stop curtain, remove the grouting tool 4 and use an acoustic wave monitor to detect the grouting density of the cavity part;

[0078] Step 3.7, detect the grouting density of the cavity part through the acoustic wave monitor, so that the grouting density is not less than 1220 kg / m 3 , if the specified grouting density is not reached, return to Step 3.3 and continue to execute the following steps;

[0079] Step 4, after the slurry in the back area 5 of the shield segment solidifies, continue to open the embedded grouting hole 1.1 to a greater depth:

[0080] Step 4.1, use a drill to open the embedded grouting hole 1.1, with the opening depth of drilling 3 m in the direction of the outside of the shield segment 1, and install the grouting tool 4 in the embedded grouting hole 1.1;

[0081] Step 4.2, during the process of installing the grouting tool 4 in the embedded grouting hole 1.1, ensure that the second grouting pipe 4.1.2 is inserted to the bottom of the embedded grouting hole 1.1, and connect the grouting pump 2 with the grouting tool 4 through the grouting pipeline;

[0082] Step 5, inject the mixed slurry into the deep grouting area 6:

[0083] Step 5.1, start the double-fluid grouting machine and the gate valve 4.4 to inject the mixed slurry into the deep grouting area 6;

[0084] Step 5.2, during the process of filling the mixed slurry into the deep grouting area 6, control the injection speed and injection volume of the mixed slurry through the gate valve 4.4. The injection flow rate of the mixed slurry is 1.5 m 3 / min;

[0085] Step 5.3, monitor the grouting volume and grouting pressure of each ring of shield segment 1, and control the grouting pressure of the grouting pump 2 at 0.2 - 0.4 Mpa;

[0086] Step 5.4, add an appropriate amount of bentonite to the mixed slurry to promote the flow of the mixed slurry and adjust the grouting pressure;

[0087] Step 6: Use an acoustic monitor to check the grouting effect, and use cement to seal the pre-embedded grouting holes, completing the reinforcement operation on the formation by grouting.

[0088] Further, in Step 3.2, the cement in the single-component slurry is Portland cement of grade 42.5 or above, and the water-cement ratio is 1.5:1, 1:1, 0.75:1.

[0089] Further, in Step 3.3, connect the grouting pipeline to the gate valve 4.4, open the gate valve 4.4, and inject the single-component slurry into the area 5 on the back of the shield segment around the pre-embedded grouting hole 1.1 through the grouting pump 2. Specifically, it includes:

[0090] Step 3.3.1: First, pump a predetermined amount of thick cement slurry with a water-cement ratio of 0.75:1 into the area 5 on the back of the shield segment around the pre-embedded grouting hole 1.1. After the cement slurry is initially stable, conduct secondary grouting.

[0091] Step 3.3.2: Then, pump a predetermined amount of standard cement slurry with a water-cement ratio of 1:1 into the area 5 on the back of the shield segment around the pre-embedded grouting hole 1.1. After the cement slurry is stable, conduct tertiary grouting.

[0092] Step 3.3.3: Finally, pump a predetermined amount of thin cement slurry with a water-cement ratio of 1.5:1 into the area 5 on the back of the shield segment around the pre-embedded grouting hole 1.1. After the cement slurry is stable, seal the hole.

[0093] Further, during the process of injecting the single-component slurry into the area 5 on the back of the shield segment around the pre-embedded grouting hole 1.1 in Step 3.3, an early-strength agent is incorporated to increase the early strength of the slurry. The early-strength agent is composed of lithium sulfate, polycarboxylate water-reducing agent, and air-entraining agent. Among them, the weight percentages of each component are: lithium sulfate 65%, polycarboxylate water-reducing agent 30%, and sodium dodecylbenzenesulfonate 5%.

[0094] Further, in Step 5, the water glass used in the mixed slurry has a modulus of 2.4 - 2.8 and a concentration of 30 - 45°Be.

[0095] Further, before injecting the mixed slurry into the deep grouting area 6 in Step 5 by opening the double-fluid grouting machine and the gate valve 4.4, it includes: performing secondary stirring on the mixed slurry in the slurry storage tank 3.1 to prevent precipitation and segregation of the mixed slurry and avoid pipe blockage of the pipeline.

[0096] Further, the dosage of water glass in the mixed slurry is determined according to the requirement of the slurry initial setting time at the construction site.

[0097] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present invention. It should be understood that the above description is only the specific embodiments of the present invention and is not used to limit the protection scope of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A grouting reinforcement device for the broken zone stratum of a shield tunnel, characterized in that, The grouting reinforcement equipment includes: shield segments, grouting pumps, slurry storage tanks and grouting tools; The shield segments are installed inside the tunnel. Embedded grouting holes are provided on the inner surface of the shield segments. A shield segment back area and a deep grouting area are sequentially arranged outside the shield segments. 16 embedded grouting holes are provided on the shield segments, and a gate valve is correspondingly installed for each embedded grouting hole; The grouting pump and the slurry storage tank are arranged inside the shield segments, and the grouting pump is communicated with the slurry storage tank through a conveying pipeline; The slurry storage tank includes a slurry storage tank body and a stirrer. The injection port of the slurry storage tank body is communicated with a cement slurry conveying pipe and a water glass conveying pipe respectively through a Y-shaped pipe. The stirrer is arranged inside the slurry storage tank body to stir the mixed slurry injected into the slurry storage tank body; The grouting tool sequentially passes through the embedded grouting hole, the shield segment back area and the deep grouting area. The grouting tool includes a grouting pipe, a pipe valve connector, a screw thread and a gate valve; the pipe valve connector is located inside the shield segment, and the pipe valve connector is connected with the shield segment through the screw thread. A limit groove and a positioning protrusion are respectively arranged at both ends of the pipe valve connector. The grouting pipe is composed of a first grouting pipe and a second grouting pipe. The first grouting pipe is sequentially arranged through the shield segment and the shield segment back area. A fixed groove is arranged on the left side of the first grouting pipe. The left side of the first grouting pipe and the right side of the pipe valve connector are inserted and fixed through the positioning protrusion and the fixed groove. The second grouting pipe penetrates through the deep grouting area. The gate valve is arranged in the limit groove on the left side of the pipe valve connector. Plum blossom-shaped holes are arranged on the side surface of the second grouting pipe, and the distance between the plum blossom-shaped holes is 200 mm.

2. A method for grouting reinforcement using the grouting reinforcement device for the broken zone stratum of a shield tunnel according to claim 1, characterized in that, The grouting reinforcement method includes the following steps: Step 1, use a shield segment crane to lift 6 shield segments into the tunnel and assemble the shield segments in the tunnel: Step 1.1, assemble 6 shield segments by using the staggered joint assembly method, and then install the remaining 1 shield segment symmetrically from bottom to top and left and right. Connect and fix each shield segment through circumferential bolts and longitudinal bolts; Step 1.2, after installing the entire ring of shield segments, use a pneumatic wrench to fix all bolts and plug the lifting holes; Step 2, open embedded grouting holes on the shield segments and install grouting tools in the embedded grouting holes: Step 2.1, the embedded grouting holes are evenly arranged on each ring of shield segments. Drill through a drill to the cavity part of the shield segment back area, and clean the slag water in the cavity part; Step 2.2, sequentially install the grouting pipe and the pipe valve connector into the embedded grouting hole, then install the gate valve in the limit groove, and make the gate valve exposed on the surface of the shield segment; Step 3, prepare the slurry to be injected into the embedded grouting holes in the mixing station: Step 3.1, in the mixing station, prepare single slurry according to the water-cement weight ratio of 1:1 for cement slurry, and prepare a cement slurry and water glass mixed slurry according to the volume ratio of 1:1 for cement slurry and water glass; Step 3.2: Deliver the single slurry to the slurry storage tank through the grouting pipeline. After the single slurry is delivered to the storage tank body, start the agitator to evenly agitate the single slurry for 5 - 10 minutes to prevent the slurry from coagulating or segregating. Step 3.3: Connect the grouting pipeline with the gate valve, open the gate valve, and inject the single slurry into the area on the back of the shield segment around the pre-buried grouting hole through the grouting pump to form a water-stop curtain. Step 3.4, during the process of filling the single slurry into the cavity part, control the injection speed and injection volume of the single slurry through the gate valve, and the injection flow rate of the single slurry is 2 m 3 / min; Step 3.5: Monitor the grouting volume and grouting pressure of each ring of shield segments through the pressure sensor set on the grouting pipeline, and control the grouting pressure of the grouting pump at 0.2 - 1 MPa. Step 3.6: After the single slurry fills the cavity area and forms a water-stop curtain, remove the grouting tool and use an acoustic monitor to detect the grouting density of the cavity area. Step 3.7, use an acoustic wave monitor to detect the grouting density in the cavity area, so that the grouting density is not less than 1220 kg / m 3 . If the specified grouting density is not achieved, return to Step 3.3 and continue to execute the following steps; Step 4: After the slurry in the area on the back of the shield segment solidifies, continue to open the pre-buried grouting hole deeper: Step 4.1: Use a drill to open the pre-buried grouting hole, with the opening depth drilling 3 m in the direction of the outside of the shield segment, and install the grouting tool in the pre-buried grouting hole. Step 4.2: During the process of installing the grouting tool in the pre-buried grouting hole, ensure that the second grouting pipe is inserted to the bottom of the pre-buried grouting hole, and connect the grouting pump with the grouting tool through the grouting pipeline. Step 5: Inject the mixed slurry into the deep grouting area: Step 5.1: Open the double-fluid grouting machine and the gate valve to inject the mixed slurry into the deep grouting area. Step 5.2, during the process of filling the mixed slurry into the deep grouting area, control the injection speed and injection volume of the mixed slurry through the gate valve. The injection flow rate of the mixed slurry is 1.5m 3 / min; Step 5.3: Monitor the grouting volume and grouting pressure of each ring of shield segments, and control the grouting pressure of the grouting pump at 0.2 - 0.4 Mpa. Step 5.4: Add an appropriate amount of bentonite to the mixed slurry to promote the flow of the mixed slurry and adjust the grouting pressure. Step 6: Use an acoustic monitor to check the grouting effect, and use cement to seal the pre-buried grouting hole to complete the grouting and reinforce the formation.

3. A method for grouting reinforcement using the grouting reinforcement device for the broken zone stratum of a shield tunnel according to claim 2, characterized in that, In Step 3.2, the cement in the single liquid slurry uses Portland cement above grade 42.5, and the water-cement ratio is 1.5:1, 1:1, 0.75:

1.

4. A method for grouting reinforcement using the grouting reinforcement device for the broken zone stratum of a shield tunnel according to claim 2, characterized in that, Step 3.3: Connect the grouting pipeline with the gate valve, open the gate valve, and inject the single slurry into the area on the back of the shield segment around the pre-buried grouting hole through the grouting pump, specifically including: Step 3.3.1: First, pump a predetermined amount of thick cement slurry with a water-cement ratio of 0.75:1 into the area on the back of the shield segment around the pre-buried grouting hole. After the cement slurry is initially stable, conduct secondary grouting. Step 3.3.2: Then, pump a predetermined amount of standard cement slurry with a water-cement ratio of 1:1 into the area on the back of the shield segment around the pre-buried grouting hole. After the cement slurry is stable, conduct tertiary grouting. Step 3.3.3: Finally, pump a predetermined amount of thin cement slurry with a water-cement ratio of 1.5:1 into the area on the back of the shield segment around the pre-buried grouting hole. After the cement slurry is stable, seal the hole.

5. The method for grouting reinforcement of the stratum in the broken zone of the shield tunnel using the grouting reinforcement equipment according to claim 2, characterized in that, During the process of injecting the single slurry into the area on the back of the shield segment around the pre-buried grouting hole in Step 3.3, add an early strength agent to improve the early strength of the slurry. The early strength agent is composed of lithium sulfate, polycarboxylate water reducer, and air-entraining agent. Among them, the weight percentages of each component are: lithium sulfate 65%, polycarboxylate water reducer 30%, and sodium dodecylbenzenesulfonate 5%.

6. The method for grouting reinforcement of the stratum in the broken zone of the shield tunnel using the grouting reinforcement equipment according to claim 2, characterized in that, In Step 5, the water glass in the mixed slurry has a modulus of 2.4 to 2.8 and a concentration of 30 to 45 °Be.

7. The method for grouting reinforcement of the stratum in the broken zone of the shield tunnel using the grouting reinforcement equipment according to claim 2, characterized in that, Before injecting the mixed slurry into the deep grouting area in Step 5 by starting the double-fluid grouting machine and the gate valve, it includes: secondary stirring of the mixed slurry in the slurry storage tank to prevent precipitation and segregation of the mixed slurry and avoid pipe blockage of the pipeline.

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