A wellbore wall joint connection structure and a construction method thereof

Abstract

The application belongs to the technical field of mine construction engineering, and particularly relates to a drilling well wall joint connecting structure and a construction method thereof. The drilling well wall joint connecting structure comprises an upper well wall segment and a lower well wall segment, and a joint box is connected between the upper well wall segment and the lower well wall segment. The joint box comprises a first flange, a second flange, an inner sealing plate and an outer sealing plate. The first flange is fixedly connected to the bottom end of the upper well wall segment, and the second flange is fixedly connected to the top end of the lower well wall segment. The side close to the inner wall and the side close to the outer wall of the upper well wall segment and the lower well wall segment are both provided with a plurality of vertical steel bars which are distributed in the circumferential direction of the well wall segment. The vertical steel bars in the upper well wall segment and the vertical steel bars in the lower well wall segment are connected in the joint box. The lower part of the upper well wall segment is provided with a grouting pipe which is communicated with the joint box. The drilling well wall joint has the advantages of strong vertical tensile and horizontal shear resistance, large rigidity and good water sealing performance.

Description

Technical Field

[0001] This invention belongs to the field of mining construction engineering technology, specifically relating to a drilling wellbore joint connection structure and its construction method. Background Technology

[0002] Drilling is a special well-sinking method commonly used in water-rich and soft strata in my country. The support structure of the wellbore (i.e., the well wall) is usually a single-layer reinforced concrete structure. When the wellbore depth is large, a combination structure of steel plates (inner steel plates, outer steel plates, or double-layer steel plates) and reinforced concrete (or concrete) is also used to improve the radial bearing capacity.

[0003] The wellbore is prefabricated in sections on the ground, with flanges (circular steel plates) at the upper and lower ends of each section. If the wellbore is reinforced with steel bars, arc-shaped serrated steel plates (commonly known as "tooths") are welded to the lower surface of the upper flange and the upper surface of the lower flange, and the two ends of the vertical steel bars are welded to the corresponding "tooths".

[0004] After the wellbore is drilled to the designed depth, the drill string is removed from the wellbore, and the prefabricated sections of the wellbore are joined together section by section. The wellbore is then lowered to the bottom of the wellbore in the well washing medium. When joining the wellbore sections, the upper and lower sections are welded together using flanges (lower flange of the upper section and upper flange of the lower section) with fillet welds (single or double sides). The gap between the two flanges is then filled with grout (usually cement grout) through pre-embedded inter-section grouting pipes to meet the water sealing performance requirements at the wellbore joint.

[0005] Because the two sections of the wellbore are connected only by fillet welds between flanges, the vertical tensile and horizontal shear strength of the wellbore is relatively weak. When the strata are stable, the constructed wellbore is generally under vertical compression and low horizontal shear force, thus the wellbore can stably bear the load. However, under certain special engineering conditions, excavation near the shaft chamber and roadway will cause displacement of the unstable strata above, and mining-induced disturbances may also lead to uneven strata displacement. When the strata undergo significant displacement due to engineering disturbances, the wellbore within a certain range will be subjected to vertical tension or horizontal shear. When the vertical tensile force or horizontal shear force at the wellbore joint exceeds the bearing capacity of the flange weld, the wellbore will be pulled apart or sheared at the flange connection. Water and sand in the strata will rush into the well through the fracture, causing danger and, in severe cases, flooding of the mine. Therefore, it is urgent to design a wellbore joint connection structure with strong vertical tensile and horizontal shear strength to solve the problem of easy breakage at traditional wellbore joints. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a drilling wellbore joint connection structure and its construction method, and specifically discloses the following technical solutions:

[0007] A drilling wellbore joint connection structure includes an upper wellbore segment and a lower wellbore segment arranged adjacent to each other. A joint box connects the upper wellbore segment and the lower wellbore segment. The joint box includes a first flange and a second flange arranged in parallel, as well as an inner sealing plate and an outer sealing plate connected between the first flange and the second flange. The first flange is fixedly connected to the bottom end of the upper wellbore segment, and the second flange is fixedly connected to the top end of the lower wellbore segment. Several vertical reinforcing bars are provided on the inner wall side and the outer wall side of both the upper and lower wellbore segments, distributed circumferentially along the wellbore segment. The vertical reinforcing bars in the upper wellbore segment extend downward through the first flange, and the vertical reinforcing bars in the lower wellbore segment extend upward through the second flange. The vertical reinforcing bars in the upper and lower wellbore segments are connected with equal strength in the joint box. A grouting pipe communicating with the joint box is provided at the lower part of the upper wellbore segment.

[0008] Furthermore, the inner sealing plate is fixedly connected between the inner side of the first flange and the inner side of the second flange, and the outer sealing plate is fixedly connected between the outer side of the first flange and the outer side of the second flange.

[0009] Furthermore, both the first flange and the second flange have a first through hole at the position corresponding to the vertical reinforcement bar, allowing the vertical reinforcement bar to pass through.

[0010] Furthermore, the vertical reinforcing bars in the upper well wall segment are welded to the vertical reinforcing bars in the lower well wall or connected by a fixed sleeve.

[0011] Furthermore, the grouting pipe is inclinedly arranged at the lower part of the upper well wall segment, and the grouting port of the grouting pipe is located on the inner side of the upper well wall segment. The grout outlet of the grouting pipe is connected to the joint box through the second through hole on the first flange.

[0012] A construction method for a drilling wellbore joint connection structure specifically includes the following steps:

[0013] S1. While drilling the well, the upper and lower well wall segments are prefabricated on the ground. During prefabrication, the first flange is fixedly connected to the bottom end of the upper well wall segment, and the second flange is fixedly connected to the top end of the lower well wall segment. The vertical steel bars in the upper well wall segment are passed downward through the first flange, and the vertical steel bars in the lower well wall segment are passed upward through the second flange. The grouting pipe is pre-embedded at the first flange according to the design requirements.

[0014] S2. Once the conditions for lowering the well wall are met, hoist the lower well wall segment into the well shaft, with its top extending a certain height above the ground to facilitate connection with the upper well wall segment.

[0015] S3. When vertical reinforcement is connected by a fixed sleeve, a fixed sleeve is installed at the top of the vertical reinforcement of the lower well wall segment, and the upper well wall segment is hoisted to the wellhead and aligned with the lower well wall segment. The joint of the vertical reinforcement of the two segments is reserved with the design requirements. Then the upper well wall segment is finely adjusted to fix it to the fixed sleeve below.

[0016] When vertical reinforcement is welded, the upper well wall segment is hoisted to the wellhead and aligned with the lower well wall segment. The vertical reinforcement of the upper and lower well wall segments is adjusted and then welded to the corresponding positions.

[0017] S4. Install pre-processed outer and inner sealing plates between two wellbore segments to form a joint box, and weld the inner sealing plates to the inner side of the first flange and the inner side of the second flange respectively, and weld the outer sealing plates to the outer side of the first flange and the outer side of the second flange respectively.

[0018] S5. Inject non-shrink filling material into the joint box through the grouting pipe, and seal the grouting pipe after grouting is completed.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] In this invention, a joint box consisting of a first flange, a second flange, an inner sealing plate, and an outer sealing plate is provided between the upper and lower wellbore segments. The vertical steel bars of the upper and lower wellbore segments are connected with equal strength. The joint box is filled with non-shrinkage filling material. The inner and outer sealing plates and the vertical steel bars together provide the vertical tensile strength at the joint of the wellbore segments. The inner and outer sealing plates, the vertical steel bars, and the filling material together provide the horizontal shear strength and stiffness at the joint. This makes the drilling wellbore joint have the advantages of strong vertical tensile and horizontal shear strength, high stiffness, and good water sealing performance. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0022] 1-Upper well wall segment, 2-First flange, 3-Second flange, 4-Inner sealing plate, 5-Outer sealing plate, 6-Vertical reinforcement, 7-Fixing sleeve, 8-Grouting pipe, 9-Lower well wall segment. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Reference Figure 1A drilling wellbore joint connection structure includes an upper wellbore segment 1 and a lower wellbore segment 9 arranged adjacent to each other, with a joint box connecting the upper wellbore segment 1 and the lower wellbore segment 9. The joint box includes a first flange 2 and a second flange 3 arranged in parallel, and an inner sealing plate 4 and an outer sealing plate 5 connecting the first flange 2 and the second flange 3. The first flange 2 is fixedly connected to the bottom end of the upper wellbore segment 1, and the second flange 3 is fixedly connected to the top end of the lower wellbore segment 9. The upper wellbore segment 1 and the lower wellbore segment 9 have a joint on the side near the inner wall and a joint on the side near the outer wall. Each well wall segment is provided with several vertical reinforcing bars 6 distributed circumferentially along the well wall segments, that is, each well wall segment is provided with two rings of vertical reinforcing bars 6. The vertical reinforcing bars 6 in the upper well wall segment 1 pass downward through the first flange 2, and the vertical reinforcing bars 6 in the lower well wall segment 9 pass upward through the second flange 3. The vertical reinforcing bars 6 in the upper well wall segment 1 and the vertical reinforcing bars 6 in the lower well wall segment 9 are connected with equal strength in the joint box. The lower part of the upper well wall segment 1 is provided with a grouting pipe 8 communicating with the joint box. The joint box is filled with non-shrink filling material.

[0025] In this embodiment, both the inner sealing plate 4 and the outer sealing plate 5 are cylindrical. The inner sealing plate 4 is fixedly connected between the inner side of the first flange 2 and the inner side of the second flange 3, and the outer sealing plate 5 is fixedly connected between the outer side of the first flange 2 and the outer side of the second flange 3. The first flange 2, the second flange 3, the inner sealing plate 4, and the outer sealing plate 5 together form a joint box for filling with non-shrinkage filling material.

[0026] In this embodiment, the first flange 2 and the second flange 3 are provided with first through holes for the vertical reinforcing bars 6 to pass through, so that the vertical reinforcing bars 6 can pass through the corresponding flanges and extend into the joint box.

[0027] In this embodiment, the vertical reinforcing bars 6 in the upper well wall segment 1 and the vertical reinforcing bars 6 in the lower well wall 9 are connected by a fixing sleeve 7. Specifically, the vertical reinforcing bars 6 at the top of the lower well wall segment 9 are inserted into and fixedly connected to the fixing sleeve 7 from the bottom, and the vertical reinforcing bars 6 at the bottom of the upper well wall segment 1 are inserted into and fixedly connected to the fixing sleeve 7 from the top. The fixing sleeve 7 facilitates the butt joint and fixation of the vertical reinforcing bars 6. In other embodiments, the vertical reinforcing bars 6 of the upper well wall segment 1 and the vertical reinforcing bars 6 of the lower well wall segment 9 can also be directly butt-welded.

[0028] In this embodiment, the grouting pipe 8 is inclinedly arranged at the lower part of the upper well wall segment 1, and the grouting port of the grouting pipe 8 is located on the inner side of the upper well wall segment 1, so as to facilitate grouting from the inner side of the upper well wall segment 1 into the joint box. The grout outlet of the grouting pipe 8 is connected to the joint box through the second through hole on the first flange 3.

[0029] A construction method for a drilling wellbore joint connection structure specifically includes the following steps:

[0030] S1. While drilling the well, the upper well wall segment 1 and the lower well wall segment 9 are prefabricated on the ground. During prefabrication, the first flange 2 is fixedly connected to the bottom end of the upper well wall segment, the second flange 3 is fixedly connected to the top end of the lower well wall segment, the vertical steel bar 6 in the upper well wall segment is passed downward through the first flange, the vertical steel bar 6 in the lower well wall segment is passed upward through the second flange, and the grouting pipe 8 is pre-embedded at the first flange according to the design requirements.

[0031] S2. Once the conditions for lowering the well wall are met, lower well wall segment 9 is hoisted into the well shaft, with its top extending a certain height above the ground to facilitate connection with upper well wall segment 1.

[0032] S3. When the vertical reinforcement is connected by a fixed sleeve, the fixed sleeve 7 is installed on the top of the vertical reinforcement of the lower well wall segment 9, and the upper well wall segment 1 is hoisted to the wellhead and aligned with the lower well wall segment 9. The joint of the vertical reinforcement 6 of the two is reserved with the height required by the design. Then the upper well wall segment is finely adjusted to fix it to the fixed sleeve below.

[0033] When welding vertical reinforcement bars, the upper well wall segment 1 is hoisted to the wellhead and aligned with the lower well wall segment 9. The vertical reinforcement bars of the upper and lower well wall segments are adjusted, and then the corresponding vertical reinforcement bars are welded after they are in place.

[0034] S4. Install the pre-processed outer sealing plate 5 and inner sealing plate 4 between the two well wall segments to form a joint box, and weld the inner sealing plate to the inner side of the first flange and the inner side of the second flange respectively, and weld the outer sealing plate to the outer side of the first flange and the outer side of the second flange respectively.

[0035] S5. Inject non-shrink filling material into the joint box through the grouting pipe 8, and seal the grouting pipe after grouting is completed.

[0036] In this embodiment, the non-shrink filling material can be non-shrink concrete or other non-shrink grouting materials.

[0037] In this invention, a joint box consisting of a first flange 2, a second flange 3, an inner sealing plate 4, and an outer sealing plate 5 is provided between the upper and lower well wall segments. The vertical reinforcing bars 6 of the upper and lower well wall segments are connected with equal strength. The joint box is filled with non-shrinkage filling material. The inner and outer sealing plates and the vertical reinforcing bars 6 together provide the vertical tensile strength at the joint of the well wall segments. The inner and outer sealing plates, the vertical reinforcing bars 6, and the filling material together provide the horizontal shear strength and stiffness at the joint. This makes the drilling well wall joint have the advantages of strong vertical tensile and horizontal shear strength, high stiffness, and good water sealing performance.

[0038] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the technical scope of the present invention. Therefore, any minor modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A construction method for a drilling wellbore joint connection structure, characterized in that, The drilling wellbore joint connection structure includes an upper wellbore segment and a lower wellbore segment arranged adjacent to each other. A joint box connects the upper wellbore segment and the lower wellbore segment. The joint box includes a first flange and a second flange arranged in parallel, as well as an inner sealing plate and an outer sealing plate connected between the first flange and the second flange. The first flange is fixedly connected to the bottom end of the upper wellbore segment, and the second flange is fixedly connected to the top end of the lower wellbore segment. Several vertical reinforcing bars are provided on the inner wall side and the outer wall side of both the upper wellbore segment and the lower wellbore segment, respectively, distributed circumferentially along the wellbore segment. The vertical reinforcing bars in the upper wellbore segment extend downward through the first flange, and the vertical reinforcing bars in the lower wellbore segment extend upward through the second flange. The vertical reinforcing bars in the upper wellbore segment and the vertical reinforcing bars in the lower wellbore segment are connected with equal strength in the joint box. A grouting pipe communicating with the joint box is provided at the lower part of the upper wellbore segment. The construction method specifically includes the following steps: S1. While drilling the well, the upper and lower well wall segments are prefabricated on the ground. During prefabrication, the first flange is fixedly connected to the bottom end of the upper well wall segment, and the second flange is fixedly connected to the top end of the lower well wall segment. The vertical steel bars in the upper well wall segment are passed downward through the first flange, and the vertical steel bars in the lower well wall segment are passed upward through the second flange. The grouting pipe is pre-embedded at the first flange according to the design requirements. S2. Once the conditions for lowering the well wall are met, hoist the lower well wall segment into the well shaft, with its top extending a certain height above the ground to facilitate connection with the upper well wall segment. S3. When vertical reinforcement is connected by a fixed sleeve, a fixed sleeve is installed at the top of the vertical reinforcement of the lower well wall segment, and the upper well wall segment is hoisted to the wellhead and aligned with the lower well wall segment. The joint of the vertical reinforcement of the two segments is reserved with the design requirements. Then the upper well wall segment is finely adjusted to fix it to the fixed sleeve below. When vertical reinforcement is welded, the upper well wall segment is hoisted to the wellhead and aligned with the lower well wall segment. The vertical reinforcement of the upper and lower well wall segments is adjusted and then welded to the corresponding positions. S4. Install pre-processed outer and inner sealing plates between two wellbore segments to form a joint box, and weld the inner sealing plates to the inner side of the first flange and the inner side of the second flange respectively, and weld the outer sealing plates to the outer side of the first flange and the outer side of the second flange respectively. S5. Inject non-shrink filling material into the joint box through the grouting pipe, and seal the grouting pipe after grouting is completed.

2. The construction method for a drilling wellbore joint connection structure according to claim 1, characterized in that, The inner sealing plate is fixedly connected between the inner side of the first flange and the inner side of the second flange, and the outer sealing plate is fixedly connected between the outer side of the first flange and the outer side of the second flange.

3. The construction method for a drilling wellbore joint connection structure according to claim 1, characterized in that, Both the first flange and the second flange have a first through hole at the position corresponding to the vertical reinforcement bar, allowing the vertical reinforcement bar to pass through.

4. The construction method of a drilling wellbore joint connection structure according to claim 1, characterized in that, The vertical reinforcing bars in the upper well wall segment are welded to or connected to the vertical reinforcing bars in the lower well wall through a fixed sleeve.

5. The construction method for a drilling wellbore joint connection structure according to claim 1, characterized in that, The grouting pipe is inclinedly arranged at the lower part of the upper well wall segment, and the grouting port of the grouting pipe is located on the inner side of the upper well wall segment. The grout outlet of the grouting pipe is connected to the joint box through the second through hole on the first flange.

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