Pilot hole collapse management structure

Abstract

The utility model belongs to engineering vertical shaft technical field discloses a pilot hole collapse processing structure. Including pilot hole, the inside wall of pilot hole forms and has predicted collapse section, separates the inside wall of pilot hole into collapse upper section and collapse lower section, and well ring structure is set up around the circumference side of pilot hole, well ring structure includes a plurality of well ring walls, the well ring wall of corresponding predicted collapse section is support wall, support wall includes first support wall section of being located in collapse upper section and second support wall section of being located in collapse lower section, first support wall section is set up from predicted collapse section upwards and presents the stepped form to form the stepped surface to the upwards. Through setting first support wall section to predicted collapse section, greatly reduce the safety risk that vertical shaft excavation brings. Simple structure, easy to construction, step excavation, avoid secondary collapse.

Description

Technical Field

[0001] This utility model relates to the field of engineering shaft technology, and in particular to a pilot hole collapse treatment structure. Background Technology

[0002] The shaft was excavated using blasting, with a pilot hole drilled using an impact drill. Excavation proceeded upwards through the pilot hole. In poor geological conditions, the pilot hole was highly susceptible to collapse, creating an inverted cavity at the bottom of the shaft, significantly increasing the safety risks of the excavation.

[0003] Traditional vertical shaft lock ring beams: The planar ring beams and the lower void area form a cantilever structure, which is prone to triggering a chain of collapses; the unsealed guide holes become stress release channels, which exacerbate the loosening of the surrounding rock. Utility Model Content

[0004] The main purpose of this utility model is to provide a pilot hole collapse treatment structure, which aims to solve the problem of vertical shaft blasting excavation in water conservancy and hydropower projects.

[0005] To achieve the above objectives, this utility model provides a pilot hole collapse treatment structure for pilot holes in hydraulic engineering shafts. The pilot hole collapse treatment structure includes: A pilot hole, wherein a predicted collapse section is formed on the inner wall of the pilot hole, dividing the inner wall of the pilot hole into an upper collapse section and a lower collapse section; and, The well ring structure is arranged around the periphery of the pilot hole. The well ring structure includes multiple well ring walls. The well ring wall corresponding to the predicted collapse section is a support wall. The support wall includes a first support wall section provided in the upper collapse section and a second support wall section provided in the lower collapse section. The first support wall section is arranged in a stepped shape from the predicted collapse section upward to form an upward step surface.

[0006] In one embodiment, the first support wall section includes a reinforced concrete layer and a first steel mesh layer arranged sequentially from the inside to the outside of the well ring structure.

[0007] In one embodiment, the reinforced concrete layer includes micro-expansion reinforced concrete and a surface layer of reinforcing bars disposed within the micro-expansion reinforced concrete.

[0008] In one embodiment, the pilot hole collapse treatment structure further includes a locking ring beam, which is disposed on the ground layer and has an exposure opening formed on it. The exposure opening is disposed corresponding to the pilot hole and also corresponding to the well ring wall. The upper end of the well ring wall extends to the upper side of the ring beam, and is stepped between it and the lock ring beam.

[0009] In one embodiment, the pilot hole collapse treatment structure further includes a well ring locking anchor rod, which is inserted through the ring beam and buried in the stratum.

[0010] In one embodiment, the first support wall section further includes a plurality of first mortar anchors, which are arranged at intervals in the vertical direction. One end of each first mortar anchor is buried in the circumferential stratum, and the other end is buried in the reinforced concrete layer.

[0011] In one embodiment, the second support wall segment includes a second steel mesh layer.

[0012] In one embodiment, the second support wall section further includes a plurality of second mortar anchors, which are spaced apart in the vertical direction. One end of each second mortar anchor is buried in the circumferential stratum, and the other two ends are buried in the second steel mesh layer.

[0013] In one embodiment, the pilot hole is backfilled with excavated material.

[0014] In one embodiment, the space between the first support wall section and the pilot hole is backfilled with the same grade of concrete.

[0015] This invention provides a pilot hole collapse treatment structure for pilot holes in hydraulic engineering shafts. In this structure, the well ring structure includes multiple well ring walls. The well ring wall corresponding to the predicted collapse section serves as a support wall. The support wall includes a first support wall section located in the upper collapse section and a second support wall section located in the lower collapse section. The first support wall section is stepped upwards from the predicted collapse section, forming an upward-facing stepped surface. By setting the first support wall section for the predicted collapse section, the safety risks associated with shaft excavation are greatly reduced. The structure is simple, easy to construct, and the stepped excavation avoids secondary collapse. Attached Figure Description

[0016] Figure 1 This is a front sectional view of the pilot hole collapse treatment structure provided in the embodiment of this utility model. Figure 2 This is a side sectional view of the pilot hole collapse treatment structure provided in the embodiment of this utility model. Figure 3 yes Figure 1 A top-view sectional view of the structure along the central axis AA; Figure 4 yes Figure 1 A top-view sectional view of the structure along the middle BB. Figure 5 yes Figure 1 A top-view sectional view of the structure along the CC axis; Figure 6 yes Figure 1 A top-view sectional view of the structure along the middle DD; Figure 7 yes Figure 1 A top-view sectional view of the structure along the middle EE; Explanation of icon numbers: 100. Pilot hole collapse treatment structure; 1. Pilot hole; 21. Support wall; 21a. First support wall section; 211. Reinforced concrete layer; 212. First steel mesh layer; 213. First mortar anchor; 21b. Second support wall section; 214. Second steel mesh layer; 215. Second mortar anchor; 3. Lock ring beam; 4. Well ring lock anchor.

[0017] The realization of the purpose, functional features and advantages of this utility model will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] It should be noted that if the embodiments of this utility model involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0020] Furthermore, if the embodiments of this utility model involve descriptions such as "first" or "second," these 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. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, 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 utility model.

[0021] Please see Figures 1 to 2This utility model provides a pilot hole collapse treatment structure 100 for pilot holes of vertical shafts in hydraulic engineering. The pilot hole collapse treatment structure includes a pilot hole 1 and a well ring structure. A predicted collapse section is formed on the inner sidewall of the pilot hole 1, dividing the inner sidewall of the pilot hole 1 into an upper collapse section and a lower collapse section. The well ring structure is arranged around the periphery of the pilot hole 1. The well ring structure includes multiple well ring walls. The well ring wall corresponding to the predicted collapse section is a support wall 21. The support wall 21 includes a first support wall section 21a provided in the upper collapse section and a second support wall section 21b provided in the lower collapse section. The first support wall section 21a is arranged in a stepped shape from the predicted collapse section upward to form an upward stepped surface.

[0022] This utility model provides a pilot hole collapse treatment structure 100 for pilot holes in hydraulic engineering shafts. In the pilot hole collapse treatment structure 100, the shaft ring structure includes multiple shaft ring walls. The shaft ring wall corresponding to the predicted collapse section is a support wall 21. The support wall 21 includes a first support wall section 21a located in the upper collapse section and a second support wall section 21b located in the lower collapse section. The first support wall section 21a is stepped upwards from the predicted collapse section to form an upward-facing stepped surface. By setting the first support wall section 21a for the predicted collapse section, the safety risks associated with shaft excavation are greatly reduced. The structure is simple, easy to construct, and the stepped excavation avoids secondary collapse.

[0023] It should be noted that the first support wall section 21a includes a reinforced concrete layer 211 and a first steel mesh layer 212 arranged sequentially from the inside to the outside of the well ring structure. The support is strengthened by the steel mesh and the reinforced concrete layer.

[0024] Specifically, the reinforced concrete layer 211 includes micro-expansion reinforced concrete and surface reinforcement bars disposed within the micro-expansion reinforced concrete.

[0025] Furthermore, the first support wall section 21a also includes a plurality of first mortar anchors 213, which are spaced apart vertically. One end of each first mortar anchor 213 is embedded in the circumferential stratum, and the other end is embedded in the reinforced concrete layer 211. The excavation face system uses anchors, steel mesh, and shotcrete for reinforced support.

[0026] Please see Figures 3 to 7 In addition, the pilot hole collapse treatment structure 100 also includes a locking ring beam 3, which is located on the ground layer. The locking ring beam 3 has an exposed opening corresponding to the pilot hole 1 and the well ring wall. The upper end of the well ring wall extends to the upper side of the ring beam, forming a stepped arrangement between it and the locking ring beam 3. Initial support + ring beam support form a rigid + flexible protection system.

[0027] Furthermore, the pilot hole collapse treatment structure 100 also includes a well ring lock anchor rod 4, which passes through the lock ring beam 3 and is buried in the stratum.

[0028] On the other hand, the second retaining wall section 21b includes a second steel mesh layer 214.

[0029] Furthermore, the second support wall section 21b also includes a plurality of second mortar anchors 215, which are arranged at intervals in the vertical direction. One end of the second mortar anchor 215 is buried in the circumferential stratum, and the other end is buried in the second steel mesh layer 214.

[0030] On the other hand, the pilot hole was backfilled with excavated material. The collapsed pilot hole was then backfilled and compacted with excavated soil and rock. Similarly, the first support wall section and the pilot hole are backfilled with the same grade of concrete.

[0031] In this application, the collapsed pilot hole was first backfilled and compacted with excavated soil and rock. Then, a stepped foundation trench was excavated along the direction of the pilot hole collapse. An L-shaped interlocking ring beam was installed at the top of the shaft, and the interlocking ring beam was extended downwards to the bottom boundary of the collapse. The excavation face was initially supported using systematic anchor bolts, steel mesh, and shotcrete. Finally, the space between the shaft structure concrete and the steps was backfilled with the same grade of concrete.

[0032] Wherein, the first mortar anchor and the second mortar anchor are ordinary mortar anchors, the first steel mesh layer and the second steel mesh layer are No. 6 steel mesh, and the micro-expansion reinforced concrete is shotcrete C20 concrete.

[0033] The above are merely preferred embodiments of this utility model and do not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the description and drawings of this utility model, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A pilot hole collapse treatment structure for pilot holes in hydraulic engineering shafts, characterized in that, The pilot hole collapse treatment structure includes: A pilot hole, wherein a predicted collapse section is formed on the inner wall of the pilot hole, dividing the inner wall of the pilot hole into an upper collapse section and a lower collapse section; and, The well ring structure is arranged around the periphery of the pilot hole. The well ring structure includes multiple well ring walls. The well ring wall corresponding to the predicted collapse section is a support wall. The support wall includes a first support wall section provided in the upper collapse section and a second support wall section provided in the lower collapse section. The first support wall section is arranged in a stepped shape from the predicted collapse section upward to form an upward step surface.

2. The pilot hole collapse treatment structure according to claim 1, characterized in that, The first support wall section includes a reinforced concrete layer and a first steel mesh layer arranged sequentially from the inside to the outside of the well ring structure.

3. The pilot hole collapse treatment structure according to claim 2, characterized in that, The reinforced concrete layer includes micro-expansion reinforced concrete and surface reinforcement bars disposed within the micro-expansion reinforced concrete.

4. The pilot hole collapse treatment structure according to claim 2, characterized in that, The first support wall section also includes a plurality of first mortar anchors, which are arranged at intervals in the vertical direction. One end of the first mortar anchor is buried in the circumferential stratum, and the other end is buried in the reinforced concrete layer.

5. The pilot hole collapse treatment structure according to claim 1, characterized in that, The pilot hole collapse treatment structure also includes a lock ring beam, which is located on the ground layer and has an exposure opening. The exposure opening is provided corresponding to the pilot hole and the well ring wall. The upper end of the well ring wall extends to the upper side of the ring beam, and is stepped between it and the lock ring beam.

6. The pilot hole collapse treatment structure according to claim 5, characterized in that, The pilot hole collapse treatment structure also includes a well ring anchor bolt, which is inserted through the anchor ring beam and buried in the stratum.

7. The pilot hole collapse treatment structure according to claim 1, characterized in that, The second retaining wall section includes a second steel mesh layer.

8. The pilot hole collapse treatment structure according to claim 7, characterized in that, The second support wall section also includes multiple second mortar anchors, which are spaced out in the vertical direction. One end of each second mortar anchor is buried in the circumferential stratum, and the other end is buried in the second steel mesh layer.

9. The pilot hole collapse treatment structure according to claim 1, characterized in that, The pilot hole was backfilled with excavated material.

10. The pilot hole collapse treatment structure according to claim 1, characterized in that, The first support wall section and the pilot hole are backfilled with the same grade of concrete.

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