Grouting process for building gap behind duct piece wall in TBM tunnel construction

Abstract

The invention relates to the technical field of TBM (Tunnel Boring Machine) tunnel grouting, in particular to a grouting process for a building gap behind a duct piece wall in TBM tunnel construction. Welding and mounting a slurry stopping plate at the tail of the shield before the shield is started, and sealing; a shield hoisting hole is opened to serve as a grouting hole; a traditional pea gravel backfilling system in the shield is dismantled, and a stirring and grouting integrated machine is installed; the synchronous grouting material type and proportion are selected, and it is ensured that gaps between segments and the stratum are filled compactly; during starting tunneling, after a shield tail completely enters a tunnel, synchronous grouting is carried out along with propelling of a shield tunneling machine, during normal tunneling, shield tail synchronous grouting needs to be carried out while shield tunneling is carried out, and during through tunneling and when the shield tail is completely separated from the tunnel, synchronous grouting can be stopped; and after grouting is completed, the grouting holes are blocked, grouting quality inspection is conducted, and secondary grouting should be conducted if the expected effect is not achieved. According to the method, pea stones are not needed, the probability that leakage points appear after grouting is low, the manpower and material resource investment of secondary water leakage opening plugging is reduced, and the overall cost of later maintenance is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of TBM tunnel grouting, and in particular to a grouting process for building gaps behind pipe segment walls in TBM tunnel construction. Background Art

[0002] The double shield TBM tunnel segment filling process is pea gravel blowing + grouting (single liquid grout). A single-track grouting plate (one layer of grouting plate) is installed on the 360° inner arc surface of the shield tail and the 72° outer arc surface of the shield tail bottom; grooves are cut at 36° on the left and right sides of the shield tail bottom to install the arch support legs.

[0003] Pea gravel filling is to fill the bottom of the segment that has come out of the shield tail through the reserved lifting hole after each ring is pushed forward; if the segment is filled with bean gravel as soon as it comes out of the shield tail, it is easy to cause the bean gravel to leak into the tunnel along the gap between the shield tail and the outer wall of the segment, resulting in a long time for manual cleaning on site, affecting the excavation efficiency. The shield tail is not grooved, and the single-channel slurry stop plate does not meet the wear resistance requirements and loses the sealing effect. If bean gravel is filled after the segment has come out of the shield tail for a long distance, the problem of bean gravel leakage can be solved, but it will cause the segment that has come out of the shield tail and has not been filled with bean gravel to lack vertical support, which is very likely to cause problems such as segment instability. In addition, bean gravel is not easy to obtain, the quality of materials obtained in different regions varies greatly, the quantity is small, and the cost is high. Most bean gravel on the market has coarse particles and a high mud content. Its disadvantages are: poor fusion with cement slurry and poor filling fluidity.

[0004] Because the pea gravel (crushed stone) has coarse particles, high mud content and poor fluidity, the filling behind the segment wall is not dense. At the same time, it is easy to cause pore channel blockage, and cavity phenomenon is easy to exist after grouting (single liquid slurry). During grouting, the formation fissure water causes the loss of slurry, and the pea gravel pore filling effect behind the segment wall is not good. The defects of double shield TBM formed tunnel segment misalignment, damage, water leakage, etc. are more prominent. Summary of the invention

[0005] In view of the above situation, in order to overcome the defects of the prior art, the present invention provides a grouting process for the building gap behind the segment wall in TBM tunnel construction to solve the problems involved in the background technology.

[0006] To achieve the above object, the present invention provides the following technical solution: a grouting process for the building gap behind the segment wall in TBM tunnel construction,

[0007] (1) Before the shield machine starts, a stop plate is welded and installed at the shield tail and sealed;

[0008] (2) Drill through the shield hoisting hole as a grouting hole, install the grouting elbow, and install the pressure gauge;

[0009] (3) Remove the traditional pea gravel backfill system in the shield and install a mixing and grouting machine;

[0010] (4) Select the type and proportion of synchronous grouting materials according to engineering geological conditions, surface settlement status, and environmental requirements to ensure that the gap between the pipe segment and the stratum is densely filled;

[0011] (5) When the shield tail is completely in the tunnel during initial excavation, synchronous grouting is carried out as the shield machine advances. During normal excavation, synchronous grouting should be carried out while the shield machine is advancing. During through excavation, when the shield tail is completely out of the tunnel, synchronous grouting can be stopped.

[0012] (6) After grouting is completed, the grouting holes are sealed and the grouting quality is inspected. If the expected effect is not achieved, secondary grouting should be carried out. Cement slurry should be used for the secondary grouting.

[0013] (7) After grouting is completed, the stop plate is cut and removed.

[0014] Furthermore, the structure of the pulp stop plate of (1) is:

[0015] It comprises an inner sealing plate and an outer sealing plate, one end of the inner sealing plate and the outer sealing plate are fixedly connected by bolts, and the other end is respectively provided with a bent portion bent inward, and an angle is formed between the inner sealing plate and the outer sealing plate;

[0016] Alternatively, the bent portions of the inner sealing plate and the outer sealing plate are provided with a plurality of bolt holes, and the bolt holes are used to fix a plurality of adjacent inner sealing plates or outer sealing plates.

[0017] Furthermore, the installation method of the slurry stop plate of (1) is as follows:

[0018] Fix one end of the inner sealing plate and the outer sealing plate together through bolts, stack and place the three stop slurry plates in an offset manner, and weld one end of the inner sealing plate and the outer sealing plate to the shield tail, fix the inner sealing plate on the stacked stop slurry plates together through bolt holes, and fix the outer sealing plate together through bolt holes, and apply sealing oil to the gaps between adjacent stop slurry plates.

[0019] Furthermore, the (2) grouting elbow is provided with an external thread matching the lifting hole, and the grouting elbow is threadedly connected to the lifting hole.

[0020] Furthermore, the structure of the mixing and grouting integrated machine of (3) includes:

[0021] A stirring grouting mechanism, a raw material storage mechanism, and a raw material conveying mechanism disposed between the stirring grouting mechanism and the raw material storage mechanism; the stirring grouting mechanism comprises a stirring tank, a slurry storage tank connected to the stirring tank, and two sets of conveying components connected to the slurry storage tank; the raw material storage mechanism comprises a dry powder bin and a horizontal screw conveyor connected to the dry powder bin; the raw material conveying mechanism is an inclined screw conveyor, the feed port of the inclined screw conveyor is connected to the raw material storage mechanism, and the discharge port is connected to the stirring tank;

[0022] A stirring motor is provided on one side of the stirring tank, and a stirring rod is connected to the stirring motor, and the stirring rod is arranged inside the stirring tank; the conveying component is a conveying pump, and a slurry outlet is arranged on the conveying pump; the raw material storage mechanism is provided with two dry powder bins, and the outlets at the lower ends of the two dry powder bins are connected to the horizontal screw conveyor; the discharge port of the horizontal screw conveyor is connected to the inclined screw conveyor;

[0023] It also includes a hoisting and transporting mechanism arranged on the top of the inner side of the pipe wall, and the hoisting and transporting mechanism is used to transport the raw material storage mechanism in the pipeline; the hoisting and transporting mechanism includes a hanging rail arranged on the top of the inner side of the pipeline, a crane arranged on the hanging rail, and a hook arranged on the crane; lifting rings are arranged on both sides of the raw material storage mechanism, and the hooks are connected to the lifting rings.

[0024] Furthermore, the synchronous grouting material of (4) is composed of dry fine aggregate, cement, mineral admixture, bentonite and additives; dry fine aggregate 60-70%; cement 12-14%; mineral admixture 14-18%; bentonite 0-5%;

[0025] The maximum particle size of the dry fine aggregate is no more than 5 mm, the mud content in the aggregate is no more than 3.0%, the mud content is no more than 1.0%, the moisture content is no more than 0.5%, and the fineness modulus is between 0.7 and 2.2;

[0026] The mineral admixture has one or more oxides of silicon, aluminum and calcium as main components, and includes fly ash, granulated blast furnace slag powder, silica fume, limestone powder, steel slag powder, phosphorus slag powder, zeolite powder or composite mineral admixture.

[0027] Furthermore, the grouting step of (5) comprises:

[0028] The raw material storage mechanism is loaded with materials and hoisted to one side of the mixing and grouting mechanism through the hoisting and transportation mechanism in the tunnel segment; the mixing and transportation mechanism is connected to the raw material storage mechanism, the slurry outlet on the delivery pump is connected to the grouting elbow through a pipeline, and the grouting mix ratio is set by computer, the water-to-material ratio is 0.37-0.38, water is added first and then the materials are added to the slurry tank for mixing, and mixing is started synchronously when the materials are added. After mixing, the materials are discharged to the slurry storage pipe, and the materials are pumped into the grouting pipe through the delivery pump. Check whether there is material in the slurry storage tank and whether the grouting hole is full. If it is full, replace the grouting point, clean the pipeline and equipment, and carry out the next cycle. If it is not full, continue grouting. After grouting the segment hoisting hole, the grouting port should be blocked;

[0029] During grouting, the grouting should be carried out symmetrically at multiple points through the segment lifting holes. The grouting points are 1 o'clock, 2 o'clock, 4 o'clock, 8 o'clock, 9 o'clock, 10 o'clock and 11 o'clock of the segment. The grouting points of adjacent segments should be staggered. Holes should be opened in the filling area to observe the slurry filling situation. The best subsequent grouting points should be determined on site through trial injection.

[0030] Furthermore, the grouting points should be determined according to the geological conditions and vertical curve elements of the construction line. To ensure that the grouting is full within the range of 180° above the tunnel arch waist, the grouting should be carried out at a position about 10 rings away from the tail shield. The grouting should be determined comprehensively based on the slope of the interval, slurry fluidity, and the setting of the slurry stop plate. The farthest position should not exceed 20 rings of the tail shield.

[0031] Furthermore, the grouting quality inspection of (6) includes segment water leakage, core sampling verification, segment wall backfill compaction, segment posture, and physical method auxiliary detection.

[0032] Furthermore, water leakage detection of pipe segments: the grouting effect is verified by checking the water leakage of pipe segments. According to the requirements of the second-level waterproofing of the interval tunnel, the pipe segments that have completed the new synchronous grouting are not allowed to leak. There can be a small amount of wet stains on the surface of the structure, but the total wet stain area should not be greater than 6 / 1000 of the total waterproof area, and any 100m 2 There should be no more than 4 wet spots on the waterproof area, and the maximum area of ​​a single wet spot should not exceed 0.2m 2 ;

[0033] Coring verification: Coring is done through the hoisting hole, with 2 sections taken for every 100 rings, and no less than 3 representative holes are taken for each section. One hole is preferably taken from the upper, middle and lower positions, and the backfilling effect is judged according to the length and completeness of the coring. After the coring is completed, synchronous grouting materials or other materials are used for grouting and sealing to ensure that the coring hole is densely grouted;

[0034] The back of the segment wall is filled tightly: check one place every 10 rings;

[0035] Segment posture: The segment posture deviation should not exceed 30mm;

[0036] Physical methods to assist detection: including geological radar, ultrasonic or elastic wave methods to detect the density of backfill behind the segment wall.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] The invention changes the traditional grouting method, adds a grout-stopping plate at the tail of the shield and combines it with the grouting method of the hoisting hole, and can achieve better grouting effect without using pea-grain stone. It can realize automatic mixing grouting through computer control to improve work efficiency. The probability of leakage after grouting is low, which reduces the human and material investment in secondary plugging of the leakage, and reduces the overall cost of grouting and subsequent maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a structural schematic diagram of a stirring and grouting integrated machine according to an embodiment of the present invention;

[0040] Figure 2It is a schematic structural diagram of a pulp stop plate according to an embodiment of the present invention;

[0041] Figure 3 It is a schematic structural diagram of a double-thread stud according to an embodiment of the present invention;

[0042] Figure 4 A schematic diagram of a segment grouting point according to an embodiment of the present invention;

[0043] Figure 5 A comparison diagram of grouting effects of an embodiment of the present invention;

[0044] In the figure:

[0045] Mixing tank 1, slurry storage tank 2, mixing motor 3, conveying pump 4, dry powder silo 5, horizontal screw conveyor 6, inclined screw conveyor 7, hanging rail 8, crane 9, hook 10, lifting ring 11, lifting rope 12, inner sealing plate 13, outer sealing plate 14, bending part 15, bolt hole 16, double threaded stud 17, nut 18. DETAILED DESCRIPTION

[0046] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0047] Embodiment 1:

[0048] Depend on Figure 1-4 As shown in FIG. 1 , a grouting process for the building gap behind the segment wall in TBM tunnel construction is used.

[0049] (1) Before the shield machine starts, a stop plate is welded and installed at the shield tail and sealed;

[0050] The structure of the slurry stop plate is:

[0051] It includes an inner sealing plate 13 and an outer sealing plate 14, one end of the inner sealing plate 13 and the outer sealing plate 14 are fixedly connected by bolts, and the other end is respectively provided with a curved portion 15 bent inward, and an angle is formed between the inner sealing plate 13 and the outer sealing plate 14; the curved portion 15 of the inner sealing plate 13 and the outer sealing plate 14 is provided with a plurality of bolt holes 16, and the bolt holes 16 are used to fix a plurality of adjacent inner sealing plates 13 or outer sealing plates 14. A double-threaded stud 17 is provided in the bolt hole, and nuts 18 are provided on both sides of the double-threaded stud, and the thread directions of the two nuts 18 are opposite. The two nuts respectively fix the plurality of inner sealing plates 13 or the outer sealing plates 14 from both sides. Since the thread directions of the two nuts 18 are opposite, when vibrated by external force, the two nuts 18 are locked with each other and cannot rotate, thereby ensuring the sealing of the slurry stop plate.

[0052] The installation method of the stop plate is:

[0053] Fix one end of the inner sealing plate and the outer sealing plate together through bolts, stack and place the three stop slurry plates in an offset manner, and weld one end of the inner sealing plate and the outer sealing plate to the shield tail, fix the inner sealing plate on the stacked stop slurry plates together through bolt holes, and fix the outer sealing plate together through bolt holes, and apply sealing oil to the gaps between adjacent stop slurry plates.

[0054] (2) The shield hoisting hole is opened as a grouting hole, and a grouting elbow and a pressure gauge are installed; the grouting elbow is provided with an external thread matching the hoisting hole, and the grouting elbow is threadedly connected to the hoisting hole.

[0055] (3) Remove the traditional pea gravel backfill system in the shield and install a mixing and grouting machine;

[0056] The structure of the mixing and grouting machine includes:

[0057] It includes a stirring grouting mechanism, a raw material storage mechanism, and a raw material conveying mechanism arranged between the stirring grouting mechanism and the raw material storage mechanism; the stirring grouting mechanism includes a stirring tank 1, a slurry storage tank 2 connected to the stirring tank 1, and two groups of conveying components connected to the slurry storage tank 2; a stirring motor 3 is arranged on one side of the stirring tank 1, and a reducer is arranged on the stirring motor 3. A stirring rod is connected to the stirring motor 3, and the stirring rod is arranged inside the stirring tank 1; the conveying component is a conveying pump 4, and a slurry outlet is arranged on the conveying pump 4. The conveying pump 4 is provided with two groups for grouting from both sides at the same time. By setting up the slurry storage tank 2, stirring and grouting can be carried out simultaneously. After the dry powder bin 5 on one side is transported to the stirring tank 1 through the raw material conveying mechanism and the stirring is completed, it is placed in the slurry storage tank 2, and the dry powder in the other dry powder bin 5 continues to be transported to the stirring tank 1 for stirring. The conveying pumps 4 on both sides can grout the shield from both sides, thereby improving work efficiency. The raw material storage mechanism includes a dry powder bin 5 and a horizontal screw conveyor 6 connected to the dry powder bin 5; the raw material storage mechanism is provided with two dry powder bins 5, and the outlets at the lower ends of the two dry powder bins 5 are connected to the horizontal screw conveyor 6; the discharge port of the horizontal screw conveyor 6 is connected to the inclined screw conveyor 7. The raw material storage mechanism can be transported to the outside of the shield by a hoisting and transportation mechanism to add powder, and then transported back to the shield for slurry mixing after the addition is completed. The raw material conveying mechanism is an inclined screw conveyor 7, the feed port of the inclined screw conveyor 7 is connected to the raw material storage mechanism, and the discharge port is connected to the mixing tank 1. It also includes a hoisting and transportation mechanism arranged at the top of the inner side of the pipe wall, and the hoisting and transportation mechanism is used to transport the raw material storage mechanism in the pipeline. The hoisting and transportation mechanism includes a hanging rail 8 arranged at the top of the inner side of the pipeline, a crane 9 arranged on the hanging rail 8, and a hanging rope 12 arranged on the crane 9, and a hook 10 is provided on the hanging rope 12. Both sides of the raw material storage mechanism are provided with hanging rings 11, and the hooks 10 are connected to the hanging rings 11.

[0058] (4) Select the type and proportion of synchronous grouting materials according to engineering geological conditions, surface settlement status, and environmental requirements to ensure that the gap between the pipe segment and the stratum is densely filled;

[0059] The synchronous grouting material is composed of dry fine aggregate, cement, mineral admixture, bentonite and additives; dry fine aggregate 60-70%; cement 12-14%; mineral admixture 14-18%; bentonite 0-5%;

[0060] The maximum particle size of the dry fine aggregate is no more than 5 mm, the mud content in the aggregate is no more than 3.0%, the mud content is no more than 1.0%, the moisture content is no more than 0.5%, and the fineness modulus is between 0.7 and 2.2;

[0061] The mineral admixture has one or more oxides of silicon, aluminum and calcium as main components, and includes fly ash, granulated blast furnace slag powder, silica fume, limestone powder, steel slag powder, phosphorus slag powder, zeolite powder or composite mineral admixture.

[0062] (5) When the shield tail is completely in the tunnel during initial excavation, synchronous grouting is carried out as the shield machine advances. During normal excavation, synchronous grouting should be carried out while the shield machine is advancing. During through excavation, when the shield tail is completely out of the tunnel, synchronous grouting can be stopped.

[0063] The grouting steps include:

[0064] The raw material storage mechanism is loaded with materials and hoisted to one side of the mixing and grouting mechanism through the hoisting and transportation mechanism in the tunnel segment; the mixing and transportation mechanism is connected to the raw material storage mechanism, the slurry outlet on the delivery pump is connected to the grouting elbow through a pipeline, and the grouting mix ratio is set by computer, the water-to-material ratio is 0.37-0.38, water is added first and then the materials are added to the slurry tank for mixing, and mixing is started synchronously when the materials are added. After mixing, the materials are discharged to the slurry storage pipe, and the materials are pumped into the grouting pipe through the delivery pump. Check whether there is material in the slurry storage tank and whether the grouting hole is full. If it is full, replace the grouting point, clean the pipeline and equipment, and carry out the next cycle. If it is not full, continue grouting. After grouting the segment hoisting hole, the grouting port should be blocked;

[0065] When grouting, it is carried out symmetrically at multiple points through the segment hoisting holes, such as Figure 4 As shown, the grouting points are 1 o'clock, 2 o'clock, 4 o'clock, 8 o'clock, 9 o'clock, 10 o'clock and 11 o'clock of the segment respectively. The grouting points of adjacent segments should be staggered, holes should be opened in the filling area to observe the slurry filling situation, and the subsequent optimal grouting points should be determined on site through trial injection.

[0066] The grouting points should be determined according to the geological conditions of the construction line and the vertical curve elements. To ensure that the grouting is full within the range of 180° above the tunnel arch waist, the grouting should be carried out at a position about 10 rings away from the tail shield. The grouting should be determined comprehensively based on the slope of the section, slurry fluidity, and the setting of the slurry stop plate. The farthest position should not exceed 20 rings of the tail shield.

[0067] (6) After grouting is completed, the grouting holes are sealed and the grouting quality is inspected. If the expected effect is not achieved, secondary grouting should be carried out. Cement slurry should be used for the secondary grouting.

[0068] Grouting quality inspection includes segment water leakage, core sampling verification, segment wall backfill compaction, segment posture, and physical method auxiliary detection.

[0069] Furthermore, water leakage detection of pipe segments: verify the grouting effect by checking the water leakage of pipe segments, and accept the pipe segments according to the requirements of the second-level waterproofing of the section tunnel. Water leakage is not allowed for the pipe segments that have completed the new synchronous grouting. There may be a small amount of wet stains on the surface of the structure, but the total wet stain area should not be greater than 6 / 1000 of the total waterproofing area, and there should be no more than 4 wet stains on any 100m2 waterproofing area, and the maximum area of ​​a single wet stain should not exceed 0.2m2;

[0070] Coring verification: Coring is done through the hoisting hole, with 2 sections taken for every 100 rings, and no less than 3 representative holes are taken for each section. One hole is preferably taken from the upper, middle and lower positions, and the backfilling effect is judged according to the length and completeness of the coring. After the coring is completed, synchronous grouting materials or other materials are used for grouting and sealing to ensure that the coring hole is densely grouted;

[0071] The back of the segment wall is filled tightly: check one place every 10 rings;

[0072] Segment posture: The segment posture deviation should not exceed 30mm;

[0073] Physical methods to assist detection: including geological radar, ultrasonic or elastic wave methods to detect the density of backfill behind the segment wall.

[0074] (7) After grouting is completed, the stop plate is cut and removed.

[0075] Depend on Figure 5 As shown, the left picture is the traditional pea-stone grouting, and the right picture is the grouting method of the present application. After grouting by the method of the present invention, the water leakage rate of the pipe segment is greatly reduced.

[0076] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A grouting process for building gaps behind segment walls in TBM tunnel construction, characterized in that: (1) Before the shield machine starts, a stop plate is welded and installed at the shield tail and sealed; (2) Drill through the shield hoisting hole as a grouting hole, install the grouting elbow, and install the pressure gauge; (3) Remove the traditional pea gravel backfill system in the shield and install a mixing and grouting machine; (4) Select the type and proportion of synchronous grouting materials according to engineering geological conditions, surface settlement status, and environmental requirements to ensure that the gap between the pipe segment and the stratum is densely filled; (5) When the shield tail is fully inside the tunnel at the beginning of excavation, grouting is carried out synchronously with the advancement of the shield machine. During normal excavation, During shield tunneling, synchronous grouting of the shield tail should be carried out. When the shield tail is completely out of the tunnel during through tunneling, Synchronous grouting can be stopped; (6) After grouting is completed, the grouting holes are sealed and the grouting quality is inspected. If the expected effect is not achieved, secondary grouting should be carried out. Cement slurry should be used for the secondary grouting. (7) After grouting is completed, the stop plate is cut and removed.

2. The grouting process for building gaps behind segment walls in TBM tunnel construction according to claim 1, characterized in that: The structure of the pulp stop plate of (1) is: It comprises an inner sealing plate and an outer sealing plate, one end of the inner sealing plate and the outer sealing plate are fixedly connected by bolts, and the other end is respectively provided with a bent portion bent inward, and an angle is formed between the inner sealing plate and the outer sealing plate; Alternatively, the bent portions of the inner sealing plate and the outer sealing plate are provided with a plurality of bolt holes, and the bolt holes are used to fix a plurality of adjacent inner sealing plates or outer sealing plates.

3. The grouting process for building gaps behind the segment wall in TBM tunnel construction according to claim 2, characterized in that: The installation method of the slurry stop plate of (1) is as follows: Fix one end of the inner sealing plate and the outer sealing plate together through bolts, stack and place the three stop slurry plates in an offset manner, and weld one end of the inner sealing plate and the outer sealing plate to the shield tail, fix the inner sealing plate on the stacked stop slurry plates together through bolt holes, and fix the outer sealing plate together through bolt holes, and apply sealing oil to the gaps between adjacent stop slurry plates.

4. The grouting process for building gaps behind segment walls in TBM tunnel construction according to claim 1, characterized in that: The (2) grouting elbow is provided with an external thread matching the lifting hole, and the grouting elbow is threadedly connected to the lifting hole.

5. The grouting process for building gaps behind segment walls in TBM tunnel construction according to claim 1, characterized in that: The structure of the mixing and grouting integrated machine (3) includes: A stirring grouting mechanism, a raw material storage mechanism, and a raw material conveying mechanism disposed between the stirring grouting mechanism and the raw material storage mechanism; the stirring grouting mechanism comprises a stirring tank, a slurry storage tank connected to the stirring tank, and two sets of conveying components connected to the slurry storage tank; the raw material storage mechanism comprises a dry powder bin and a horizontal screw conveyor connected to the dry powder bin; the raw material conveying mechanism is an inclined screw conveyor, the feed port of the inclined screw conveyor is connected to the raw material storage mechanism, and the discharge port is connected to the stirring tank; A stirring motor is provided on one side of the stirring tank, and a stirring rod is connected to the stirring motor, and the stirring rod is arranged inside the stirring tank; the conveying component is a conveying pump, and a slurry outlet is arranged on the conveying pump; the raw material storage mechanism is provided with two dry powder bins, and the outlets at the lower ends of the two dry powder bins are connected to the horizontal screw conveyor; the discharge port of the horizontal screw conveyor is connected to the inclined screw conveyor; It also includes a hoisting and transporting mechanism arranged on the top of the inner side of the pipe wall, and the hoisting and transporting mechanism is used to transport the raw material storage mechanism in the pipeline; the hoisting and transporting mechanism includes a hanging rail arranged on the top of the inner side of the pipeline, a crane arranged on the hanging rail, and a hook arranged on the crane; lifting rings are arranged on both sides of the raw material storage mechanism, and the hooks are connected to the lifting rings.

6. The grouting process for building gaps behind segment walls in TBM tunnel construction according to claim 1, characterized in that: The synchronous grouting material of (4) is composed of dry fine aggregate, cement, mineral admixture, bentonite and additives; dry fine aggregate 60-70%; cement 12-14%; mineral admixture 14-18%; bentonite 0-5%; The maximum particle size of the dry fine aggregate is no more than 5 mm, the mud content in the aggregate is no more than 3.0%, the mud content is no more than 1.0%, the moisture content is no more than 0.5%, and the fineness modulus is between 0.7 and 2.2; The mineral admixture has one or more oxides of silicon, aluminum and calcium as main components, and includes fly ash, granulated blast furnace slag powder, silica fume, limestone powder, steel slag powder, phosphorus slag powder, zeolite powder or composite mineral admixture.

7. The grouting process for building gaps behind segment walls in TBM tunnel construction according to claim 1, characterized in that: The grouting step of (5) comprises: The raw material storage mechanism is loaded with materials and hoisted to one side of the mixing and grouting mechanism through the hoisting and transportation mechanism in the tunnel segment; the mixing and transportation mechanism is connected to the raw material storage mechanism, the slurry outlet on the delivery pump is connected to the grouting elbow through a pipeline, and the grouting mix ratio is set by computer, the water-to-material ratio is 0.37-0.38, water is added first and then the materials are added to the slurry tank for mixing, and mixing is started synchronously when the materials are added. After mixing, the materials are discharged to the slurry storage pipe, and the materials are pumped into the grouting pipe through the delivery pump. Check whether there is material in the slurry storage tank and whether the grouting hole is full. If it is full, replace the grouting point, clean the pipeline and equipment, and carry out the next cycle. If it is not full, continue grouting. After grouting the segment hoisting hole, the grouting port should be blocked; During grouting, the grouting should be carried out symmetrically at multiple points through the segment lifting holes. The grouting points are 1 o'clock, 2 o'clock, 4 o'clock, 8 o'clock, 9 o'clock, 10 o'clock and 11 o'clock of the segment. The grouting points of adjacent segments should be staggered. Holes should be opened in the filling area to observe the slurry filling situation. The best subsequent grouting points should be determined on site through trial injection.

8. The grouting process for building gaps behind the segment wall in TBM tunnel construction according to claim 7, characterized in that: The grouting points should be determined according to the geological conditions of the construction line and the vertical curve elements. To ensure that the grouting is full within the range of 180° above the tunnel arch waist, the grouting should be carried out at a position about 10 rings away from the tail shield. The grouting should be determined comprehensively based on the slope of the section, slurry fluidity, and the setting of the slurry stop plate. The farthest position should not exceed 20 rings of the tail shield.

9. The grouting process for building gaps behind segment walls in TBM tunnel construction according to claim 1, characterized in that: The grouting quality inspection of (6) includes segment water leakage, core sampling verification, segment wall backfill compaction, segment posture, and physical method auxiliary detection.

10. The grouting process for building gaps behind the segment wall in TBM tunnel construction according to claim 7, characterized in that: Segment leakage detection: Verify the grouting effect by checking the segment leakage. Acceptance is carried out according to the requirements of the second-level waterproofing of the interval tunnel. Segments that have completed the new synchronous grouting are not allowed to leak. There may be a small amount of wet stains on the surface of the structure, but the total wet stain area should not be greater than 6 / 1000 of the total waterproof area, and any 100m 2 There should be no more than 4 wet spots on the waterproof area, and the maximum area of ​​a single wet spot should not exceed 0.2m 2 ; Coring verification: Coring is done through the hoisting hole, with 2 sections taken for every 100 rings, and no less than 3 representative holes are taken for each section. One hole is preferably taken from the upper, middle and lower positions, and the backfilling effect is judged according to the length and completeness of the coring. After the coring is completed, synchronous grouting materials or other materials are used for grouting and sealing to ensure that the coring hole is densely grouted; The back of the segment wall is filled tightly: check one place every 10 rings; Segment posture: The segment posture deviation should not exceed 30mm; Physical methods to assist detection: including geological radar, ultrasonic or elastic wave methods to detect the density of backfill behind the segment wall.

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