Construction method for ground treatment in construction of shield sand-pebble stratum

Abstract

The application discloses a construction method for shield sand-pebble stratum construction ground treatment, wherein a collapse part is formed by downward concave of the sand-pebble stratum, and the method comprises the following steps: laying steel plates on both sides of the ground position corresponding to the cutter head mileage position of the shield machine; forming a fence structure by surrounding the construction ground corresponding to the cutter head of the shield machine according to the first preset distance and the second preset distance; wherein the fence structure is arranged on the periphery of the collapse part; and processing the collapse part in the fence structure by using a drilling and grouting equipment to repair the collapse part and complete the construction. By forming the fence structure and processing the collapse part in the fence structure by using the drilling and grouting equipment to repair the collapse part, the stratum loss can be compensated effectively in time, the fact that the stratum is not compensated effectively is covered up, the ground surface collapse is avoided, the construction safety is improved, and the great safety risk caused by the shield machine to the ground is reduced.

Description

Technical Field

[0001] This invention relates to the field of shield tunneling technology in gravel strata, and more particularly to a construction method for surface treatment in shield tunneling in gravel strata. Background Technology

[0002] In related technologies, in water-rich sandy and gravelly strata, because the strata contain a large number of boulders and they are relatively large, the boulders are often difficult to break and remove during shield tunneling, causing the cutterhead to jam.

[0003] However, in order to free the cutterhead from its predicament, it is not advisable to resort to ground precipitation, opening the chamber to remove stones, or repeatedly rotating the cutterhead, which could cause damage to the formation.

[0004] Therefore, when strata are damaged and not effectively compensated, the sand and gravel (including boulders) strata have a certain self-stabilizing period, which often masks the fact that the strata have not been effectively compensated, eventually leading to surface subsidence and posing a significant safety risk to the ground. Summary of the Invention

[0005] The main objective of this invention is to provide a construction method for surface treatment in shield tunneling in sandy and gravelly strata, aiming to solve the technical problem of significant safety risks in shield tunneling in water-rich sandy and gravelly strata in the prior art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This invention provides a construction method for surface treatment in shield tunneling of gravel strata, wherein the gravel strata are depressed to form a collapsed portion, and the method includes:

[0008] Steel plates are laid on both sides of the ground position corresponding to the cutterhead mileage position of the tunnel boring machine;

[0009] According to the first preset distance, the construction ground corresponding to the front of the tunnel boring machine cutterhead is cordoned off;

[0010] According to the second preset distance, a fence is erected around the construction ground corresponding to the rear of the tunnel boring machine cutterhead to form a fence structure; wherein, the fence structure is set up around the periphery of the collapsed part;

[0011] Using drilling and grouting equipment, the collapsed portion is treated within the enclosure structure to repair it, thus completing the ground treatment for shield tunneling in gravel strata.

[0012] Optionally, in the above-described construction method for surface treatment in shield tunneling gravel strata, before the step of enclosing the construction surface corresponding to the front of the shield machine cutterhead according to a first preset distance, the method further includes:

[0013] The first preset distance is determined based on the actual working conditions of the tunnel boring machine in the gravel stratum and the tunnel burial depth.

[0014] Optionally, in the above-described construction method for surface treatment in shield tunneling gravel strata, before the step of enclosing the construction surface corresponding to the rear of the shield machine cutterhead according to a second preset distance to form a retaining structure, the method further includes:

[0015] The second preset distance is determined based on the main body size of the tunnel boring machine, the tunneling speed, and the initial setting time of the synchronous slurry compensation after the cutterhead disturbs the strata.

[0016] Optionally, in the above construction method for surface treatment in shield tunneling gravel strata, the first preset distance is 10m.

[0017] Optionally, in the above construction method for surface treatment in shield tunneling gravel strata, the second preset distance is 30m.

[0018] Optionally, in the above-described construction method for surface treatment in shield tunneling gravel strata, before the step of using drilling grouting equipment to treat the collapsed portion within the retaining structure to repair the collapsed portion, the method further includes:

[0019] Drilling equipment and grouting equipment are respectively installed inside the enclosure structure.

[0020] Optionally, in the above-mentioned construction method for surface treatment in shield tunneling gravel strata, the step of using drilling grouting equipment to treat the collapsed portion within the retaining structure to repair the collapsed portion and complete the construction of surface treatment for shield tunneling gravel strata includes:

[0021] Determine the excess section based on the slag discharge volume;

[0022] Locate the position of the super-square section on the ground;

[0023] Explore the geological bodies corresponding to the aforementioned super-square section;

[0024] Position the drilling rig;

[0025] Drill holes into the geological body corresponding to the super-square section at a preset depth.

[0026] Optionally, in the above-described construction method for surface treatment in shield tunneling gravel strata, before the step of using drilling grouting equipment to treat the collapsed portion within the retaining structure to repair the collapsed portion and complete the construction of surface treatment for shield tunneling gravel strata, the method further includes:

[0027] The comparison results were obtained based on the analysis and comparison of ground settlement monitoring data and the volume of excavated slag with the theoretical volume.

[0028] Determine whether the comparison results meet the preset conditions;

[0029] If so, ground drilling and grouting will be performed at the location corresponding to the comparison result to replenish the sand and gravel loss in the strata;

[0030] After the step of using drilling and grouting equipment to treat the collapsed portion within the retaining structure to repair the collapsed portion and complete the ground treatment for shield tunneling in gravel strata, the method further includes:

[0031] The barriers were removed and the road surface was washed to complete the ground treatment for shield tunneling in gravel strata.

[0032] Optionally, in the above-described construction method for surface treatment in shield tunneling gravel strata, before the step of drilling and grouting at the location corresponding to the comparison result to replenish the sand and gravel loss in the strata, if the condition is met, the method further includes:

[0033] For locations where cavities are found, first backfill with C10 concrete, then perform grouting backfilling.

[0034] Optionally, in the above-mentioned construction method for surface treatment in shield tunneling gravel strata, the preset depth is 2m from the arch crown.

[0035] The above-described one or more technical solutions provided by this invention can have the following advantages or at least achieve the following technical effects:

[0036] This invention proposes a construction method for surface treatment during shield tunneling in gravel and pebbles strata. By forming a retaining structure and using drilling and grouting equipment, the collapsed portion is treated within the retaining structure to repair it. When strata are damaged, timely and effective compensation is provided to prevent the gravel and pebbles (including boulders) strata from having a certain self-stabilizing period and masking the fact that the strata have not been effectively compensated. This avoids surface subsidence, improves construction safety, and reduces the significant safety risks posed by the shield tunneling to the ground. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1This is a schematic flowchart of a construction method for surface treatment in shield tunneling gravel strata construction according to an embodiment of the present invention;

[0039] Figure 2 for Figure 1 A detailed flowchart of step S40.

[0040] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0042] It should be noted that in the embodiments of the present invention, all directional indications (such as up, down, left, right, front, back, etc.) are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0043] In this invention, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Without further limitation, an element defined by the phrase "comprising..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element. Furthermore, the meaning of "and / or" throughout the text includes three parallel options; for example, "A and / or B" includes option A, option B, or options where both A and B are satisfied.

[0044] In this invention, unless otherwise explicitly specified and limited, the terms "connection" and "fixed" should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements.

[0045] In this invention, if there are descriptions involving "first," "second," etc., such descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features.

[0046] In this invention, the use of suffixes such as "module," "component," "part," "unit," or "unit" to denote elements is solely for the purpose of illustrative purposes and has no specific meaning in itself. Therefore, "module," "part," or "unit" can be used interchangeably.

[0047] For those skilled in the art, the specific meanings of the above terms in this invention can be understood according to the specific circumstances. Furthermore, the technical solutions of the various embodiments can be combined with each other; however, this is based on the premise that those skilled in the art can implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0048] The inventive concept of the present invention will be further explained below with reference to some specific embodiments.

[0049] This invention proposes a construction method for surface treatment in shield tunneling construction in gravel and sand strata.

[0050] Reference Figure 1 , Figure 1 This is a schematic flowchart of a construction method for surface treatment in shield tunneling gravel strata construction according to an embodiment of the present invention.

[0051] In one embodiment of the present invention, such as Figure 1 As shown, a construction method for surface treatment in shield tunneling of gravel strata, wherein the gravel strata are depressed to form a collapsed section, the method comprising:

[0052] Step S10: Lay steel plates on both sides of the ground position corresponding to the cutterhead mileage position of the tunnel boring machine;

[0053] Step S20: According to the first preset distance, set up a perimeter around the construction ground in front of the tunnel boring machine cutterhead;

[0054] Step S30: According to the second preset distance, a fence is erected around the construction ground corresponding to the rear of the tunnel boring machine cutterhead to form a fence structure; wherein the fence structure is set around the periphery of the collapsed part;

[0055] Step S40: Using drilling and grouting equipment, treat the collapsed part within the enclosure structure to repair the collapsed part and complete the ground treatment for shield tunneling in gravel strata.

[0056] It should be understood that two 2000*6000*20mm steel plates are laid on both sides of the cutterhead location of the ground-based tunnel boring machine (TBM). Enclosures are constructed 10m in front of and 30m behind the cutterhead location, with the enclosure measuring 40*6m (length*width). Drilling and grouting equipment (one geological drilling rig, one grouting machine, and one generator) are installed within the enclosure. Based on ground settlement monitoring data and a comparison of the excavated muck volume with the theoretical volume, ground drilling and grouting are performed at locations with higher data to replenish the sand and gravel lost from the strata. For locations where cavities are found, C10 concrete is first used for backfilling, followed by grouting to ensure road surface safety.

[0057] The technical solution of this invention forms a retaining structure and uses drilling and grouting equipment to treat the collapsed part within the retaining structure to repair the collapsed part. When the stratum is damaged, it is timely and effectively compensated to prevent the sand and gravel (including boulders) stratum from having a certain self-stabilizing period and masking the fact that the stratum has not been effectively compensated, thereby avoiding surface collapse, improving construction safety, and reducing the significant safety risks brought to the ground by the tunnel boring machine.

[0058] In one embodiment, before the step of enclosing the construction ground corresponding to the front of the tunnel boring machine cutterhead according to a first preset distance, the method further includes:

[0059] Step F10: Determine the first preset distance based on the actual working conditions of the tunnel boring machine in the gravel stratum and the tunnel burial depth.

[0060] It should be noted that, based on the actual working conditions of the tunnel boring machine in the gravel stratum and the tunnel burial depth, and combined with the super-cubic funnel effect of tunnel boring in the gravel stratum, the first preset distance of the enclosure range is generally considered to be about 10m.

[0061] In one embodiment, before the step of constructing a fence around the construction ground corresponding to the rear of the tunnel boring machine cutterhead according to a second preset distance, the method further includes:

[0062] Step E10: Determine the second preset distance based on the main body size of the tunnel boring machine, the tunneling speed, and the initial setting time of the synchronous slurry compensation after the cutterhead disturbs the strata.

[0063] It should be noted that, based on the size of the tunnel boring machine and the tunneling speed, and considering factors such as the initial setting time of the synchronous grout compensation after the cutterhead disturbs the strata, the second preset distance for ground treatment is generally considered to be around 30m.

[0064] In one embodiment, the first preset distance is 10m.

[0065] In one embodiment, the second preset distance is 30m.

[0066] In one embodiment, prior to the step of using drilling and grouting equipment to treat the collapsed portion within the enclosure structure to repair the collapsed portion, the method further includes:

[0067] Step T10: Drilling equipment and grouting equipment are respectively installed inside the enclosure structure.

[0068] Continue to refer to Figure 1 And refer to Figure 2 , Figure 2 for Figure 1 A detailed flowchart of step S40.

[0069] In one embodiment, such as Figure 1 and Figure 2 As shown, the steps of using drilling and grouting equipment to treat the collapsed portion within the enclosure structure to repair the collapsed portion and complete the ground treatment for shield tunneling in gravel strata include:

[0070] Step S41: Determine the excess section based on the slag discharge volume;

[0071] Step S42: Lay out the location of the super-square section on the ground;

[0072] Step S43: Explore the geological bodies corresponding to the super-square section;

[0073] Step S44: Position the drilling rig;

[0074] Step S45: Drill holes into the geological body corresponding to the super-square section at a preset depth.

[0075] It should be noted that the repair of the collapsed section can be carried out as follows: determine the excess section based on the amount of slag removed, lay out the excess section on the ground, excavate (avoid underground pipelines and ensure pipeline safety), position the drilling rig, drill holes (2m from the top of the arch), backfill the cavities with concrete and grout for compaction or loose grouting without cavities, remove the barriers and wash the road surface, restore the original state, and conduct continuous monitoring.

[0076] In one embodiment, before the step of using drilling grouting equipment to treat the collapsed portion within the retaining structure to repair the collapsed portion and complete the surface treatment construction for shield tunneling in gravel strata, the method further includes:

[0077] Step G10: Based on the ground settlement monitoring data and the analysis and comparison of the excavated muck volume with the theoretical volume, obtain the comparison results;

[0078] Step G20: Determine whether the comparison results meet the preset conditions;

[0079] Step G30: If yes, then perform ground drilling and grouting at the location corresponding to the comparison result to replenish the sand and gravel loss in the strata;

[0080] After the step of using drilling and grouting equipment to treat the collapsed portion within the retaining structure to repair the collapsed portion and complete the ground treatment for shield tunneling in gravel strata, the method further includes:

[0081] Step B10: Remove the barriers and wash the road surface to complete the ground treatment for shield tunneling in gravel strata.

[0082] It should be noted that the monitoring data warning value is determined according to the control value of the design monitoring project. Generally, the warning value for surface subsidence (uplift) is 21mm (7mm), and the deformation rate does not exceed 3mm / d.

[0083] In one embodiment, prior to the step of performing ground drilling and grouting at the location corresponding to the comparison result to replenish the sand and gravel loss in the strata, if the condition is met, the method further includes:

[0084] Step U10: For the locations where voids are found, first backfill with C10 concrete and then perform grouting backfilling.

[0085] In one embodiment, the preset depth is 2m from the top of the arch.

[0086] It should be understood that, based on the theoretical and actual muck removal volumes during tunneling, and combined with ground settlement monitoring data, a comprehensive analysis and comparison of the over-cut sections is conducted to identify cavities within these sections.

[0087] Finally, it should be noted that the sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments. The above embodiments are only optional embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made under the inventive concept of the present invention using the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are all included within the patent protection scope of the present invention.

Claims

1. A construction method for surface treatment in shield tunneling with gravel and sand strata, characterized in that, The sand and gravel strata have sunken areas forming collapsed sections, and the method includes: Steel plates are laid on both sides of the ground corresponding to the mileage position of the tunnel boring machine's cutterhead; wherein, the steel plates are 2000 mm thick. 6000 Two 20mm steel plates are laid out. According to the first preset distance, the construction ground corresponding to the front of the tunnel boring machine cutterhead is cordoned off; Based on a second preset distance, a perimeter is constructed around the construction ground corresponding to the rear of the tunnel boring machine cutterhead, forming an enclosure structure; wherein, the enclosure structure is erected around the perimeter of the collapsed section, and the enclosed area is 40m². 6m; Drilling equipment and grouting equipment are respectively installed inside the enclosure structure; wherein, one geological drilling rig, one grouting machine and one generator are installed inside the enclosure structure. Using drilling and grouting equipment, the collapsed part is treated within the enclosure structure to repair it, thus completing the ground treatment for shield tunneling in gravel strata. The first preset distance is determined based on the actual working conditions of the tunnel boring machine in the gravel stratum and the tunnel burial depth, combined with the super-square funnel effect of tunnel boring machine excavation in gravel stratum; the second preset distance is determined based on the main body size of the tunnel boring machine, the tunneling speed, and the initial setting time of synchronous slurry compensation after the cutterhead disturbs the stratum. Prior to the step of using drilling and grouting equipment to treat the collapsed portion within the enclosure structure to repair the collapsed portion, the method further includes: Based on the ground settlement monitoring data and the analysis and comparison of the excavated slag volume with the theoretical volume, a comparison result is obtained; it is determined whether the comparison result meets the preset conditions; if so, ground drilling and grouting are carried out at the location corresponding to the comparison result to replenish the sand and gravel loss in the strata; wherein, the monitoring data warning value is determined according to the control value of the design monitoring project, the ground settlement warning value is 21mm, the heave warning value is 7mm, and the deformation rate does not exceed 3mm / d. The step of using drilling and grouting equipment to treat the collapsed portion within the enclosure structure to repair the collapsed portion includes: The excess section is determined based on the volume of slag produced; the location of the excess section is marked on the ground; the geological body corresponding to the excess section is explored to avoid underground pipelines; the drilling rig is positioned; boreholes are drilled into the geological body corresponding to the excess section at a preset depth, wherein the preset depth is 2m from the arch crown; the location of the drilled cavity is first backfilled with C10 concrete and then grouted; the location without cavities and relatively loose is grouted. After the collapse was treated, the barriers were removed and the road surface was washed to restore it to its original state, and monitoring continued.

2. The construction method for surface treatment in shield tunneling gravel strata as described in claim 1, characterized in that, The first preset distance is 10m.

3. The construction method for surface treatment in shield tunneling gravel strata as described in claim 1, characterized in that, The second preset distance is 30m.

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