Red sandstone stratum foundation pit dewatering construction structure

Abstract

The utility model discloses a red sandstone stratum foundation pit dewatering construction structure, which belongs to the technical field of foundation pit dewatering and comprises a mounting ring, a drill rod sleeve, a water pumping pipe and a driving mechanism, the top of the drill rod sleeve is rotatably connected with the mounting ring, the drill rod sleeve is of a hollow structure, a water collecting area is formed in the drill rod sleeve, and the water pumping pipe is arranged in the water collecting area. The water pumping pipe is rotationally arranged in the drill rod sleeve, the diameter of the water pumping pipe is smaller than the inner diameter of the drill rod sleeve, the water pumping pipe extends to the bottom of the drill rod sleeve, a plurality of water seepage holes are formed in the side wall of the drill rod sleeve, and foundation pit underground water enters the water collecting area through the water seepage holes and is discharged through the water pumping pipe; and the driving mechanism is used for driving the drill rod sleeve to rotate. According to the red sandstone stratum foundation pit dewatering construction structure, along with the increase of the excavation depth of the foundation pit, the driving mechanism drives the drill rod sleeve and the water pumping pipe to continuously drill downwards, the drainage process does not need to be interrupted or the water pumping pipe does not need to be pulled out of the water collecting well, the operation process is simplified, and the working efficiency is improved.

Description

Technical Field

[0001] This utility model belongs to the field of foundation pit dewatering technology, and in particular relates to a construction structure for foundation pit dewatering in red sandstone strata. Background Technology

[0002] Dewatering of foundation pits is an indispensable technique in civil engineering, especially when excavating foundation pits in areas with high groundwater levels or high soil moisture content. The main purpose of dewatering is to reduce the pore water pressure in the soil by lowering the groundwater level within the foundation pit, thereby increasing the stability of the pit slope, preventing slope instability and collapse, and improving the efficiency and safety of foundation pit excavation.

[0003] During foundation pit construction, layered excavation is usually adopted. As the excavation depth decreases, the depth of the sump and dewatering structures such as wellpoint pipes need to be continuously updated. However, the existing foundation pit dewatering structure requires the removal of pumping equipment and the excavation depth of the sump. This not only increases the construction difficulty and cost, but may also lead to poor dewatering effect. Secondly, for soil layers such as red sandstone, which weather quickly and are easily softened and disintegrated when exposed to water, the stability of the sump wellhead is seriously affected, and there may be situations where the wellhead collapses and buries the pumping equipment.

[0004] Therefore, we propose a construction structure for dewatering foundation pits in red sandstone strata to solve the above problems. Utility Model Content

[0005] The purpose of this utility model is to solve the problems of high construction difficulty and poor wellhead stability in the dewatering of red sandstone foundation pits in the existing technology, and to propose a construction structure for dewatering foundation pits in red sandstone strata.

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

[0007] A construction structure for dewatering foundation pits in red sandstone strata includes an installation ring, a drill pipe sleeve, a pumping pipe, and a drive mechanism, wherein:

[0008] The top of the drill pipe sleeve is rotatably connected to the mounting ring. The drill pipe sleeve has a hollow structure, forming a water collection area inside the drill pipe sleeve. The water pumping pipe is rotatably installed inside the drill pipe sleeve, and the diameter of the water pumping pipe is smaller than the inner diameter of the drill pipe sleeve. The water pumping pipe extends to the bottom of the drill pipe sleeve. Multiple seepage holes are opened on the side wall of the drill pipe sleeve. Groundwater in the foundation pit enters the water collection area through the seepage holes and is discharged through the water pumping pipe.

[0009] The drive mechanism is used to drive the drill pipe sleeve to rotate, so that the drill pipe sleeve and the pumping pipe can continuously drill downwards as the depth of the foundation pit increases during the layered excavation of the foundation pit.

[0010] Preferably, the drill pipe sleeve includes an outer sleeve and an inner liner, the outer sleeve and the inner liner are coaxially rotatable, the bottom end of the outer sleeve is tapered and a drill bit is provided thereon, and the outer wall of the outer sleeve is also provided with a spiral conveying plate connected to the drill bit;

[0011] A torsion structure is provided between the outer sleeve and the inner liner. When the drill pipe sleeve drills downward, the inner liner is deflected to seal the seepage hole.

[0012] Preferably, the seepage hole penetrates the outer sleeve and the inner liner, forming an outer hole on the outer sleeve and an inner hole on the inner liner. When the outer hole and the inner hole coincide, the seepage hole is open; when the outer hole and the inner hole are circumferentially misaligned, the seepage hole is closed.

[0013] Preferably, the torsion structure includes a rotating shaft fixedly disposed at the bottom of the inner liner tube, a rotating hole adapted to the rotating shaft is fixedly disposed at the bottom of the outer sleeve tube, and a torsion spring is installed between the rotating shaft and the inner wall of the outer sleeve tube;

[0014] A limiting groove is provided on the inner wall of the rotating hole, and a limiting block with a width smaller than the limiting groove is provided on the part of the rotating shaft located inside the rotating hole.

[0015] Preferably, the pumping pipe includes a suction section and a connecting section, the suction section is located at the bottom inside the drill pipe sleeve, and the connecting section is connected to the top of the suction section and extends out of the drill pipe sleeve;

[0016] The water absorption section is provided with two bosses on both sides, and the inner liner tube is provided with two bosses on the side wall to restrict the axial movement of the bosses.

[0017] Preferably, the water-absorbing section is covered with a sponge filter layer, and a squeezing roller is rotatably arranged between the two protrusions, which squeezes and deforms the sponge filter layer at the corresponding position.

[0018] Preferably, the drive mechanism includes a first bevel gear fixedly installed on the top of the inner liner tube, a motor fixedly installed on the side of the mounting ring, and a second bevel gear fixedly installed at the output end of the motor, wherein the first bevel gear meshes with the second bevel gear.

[0019] Preferably, the mounting ring has a support rod and two symmetrically mounted positioning rods on its side, and the positioning rods have through holes.

[0020] In summary, the technical effects and advantages of this utility model are as follows:

[0021] This dewatering construction structure for foundation pits in red sandstone formations allows the drive mechanism to continuously drill downwards, propelling the drill rod sleeve and pumping pipe downwards as the excavation depth increases. This eliminates the need to interrupt the drainage process or pull the pumping pipe out of the sump, simplifying the operation process, improving work efficiency, ensuring the simultaneous excavation and drainage operations, and avoiding water accumulation in the foundation pit due to drainage interruptions.

[0022] This dewatering construction structure for foundation pits in red sandstone formations creates a water collection area inside the drill pipe sleeve, enhancing the overall strength and support capacity of the drill pipe sleeve. When used in easily pulverized red sandstone layers, the drill pipe sleeve can effectively prevent borehole collapse, protect the safety and stability of the foundation pit, and ensure the smooth progress of drainage operations.

[0023] This dewatering construction structure for foundation pits in red sandstone strata utilizes an outer casing and an inner liner, with a torsion structure between them. During drilling, the inner liner can be deflected, thus sealing seepage holes and preventing silt from entering the drill pipe sleeve under drilling pressure. This avoids contamination of the pumping pipe and the water collection area by silt, ensuring the cleanliness of the water collection area and reducing subsequent maintenance and cleaning costs. After drilling is completed, the inner liner automatically resets under the action of the torsion structure, reopening the seepage holes and restoring normal water collection and dewatering functions. This achieves automatic opening and closing of seepage holes, simplifies the operation process, improves drainage efficiency, and ensures the stability and reliability of foundation pit drainage.

[0024] The dewatering construction structure for the foundation pit in the red sandstone stratum uses a sponge filter layer installed outside the pumping pipe. During the drilling process, the extrusion roller squeezes the sponge filter layer, achieving the functions of extrusion discharge and self-cleaning. The sponge filter layer can effectively filter the pulverized red sandstone mud and sand, preventing it from entering the pumping pipe. Together with the extrusion roller, it achieves self-cleaning of the sponge filter layer, extends the service life of the sponge filter layer, and reduces the frequency of replacement and maintenance. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0026] Figure 2 This is a cross-sectional structural diagram of the present invention;

[0027] Figure 3 This is a schematic diagram of the outer sleeve in this utility model;

[0028] Figure 4 This is a schematic diagram of the inner liner tube structure in this utility model;

[0029] Figure 5 This is a schematic diagram of the water pumping pipe in this utility model;

[0030] Figure 6 This is a schematic diagram of the structural relationship between the limiting groove and the limiting block in this utility model.

[0031] In the diagram: 1. Mounting ring; 2. Drill rod sleeve; 21. Water seepage hole; 211. Outer hole; 212. Inner hole; 22. Outer sleeve; 221. Rotary hole; 222. Limiting groove; 23. Inner liner; 231. Rotating shaft; 232. Limiting block; 233. Extrusion roller; 234. Bevel gear one; 24. Drill bit; 25. Spiral conveyor plate; 26. Torsion spring; 3. Pumping pipe; 31. Suction section; 32. Connecting section; 33. Sponge filter layer; 4. Motor; 41. Bevel gear two. Detailed Implementation

[0032] Reference Figure 1-5 A construction structure for dewatering foundation pits in red sandstone formations includes an installation ring 1, a drill pipe sleeve 2, a pumping pipe 3, and a drive mechanism.

[0033] The top of the drill pipe sleeve 2 is rotatably connected to the mounting ring 1. During normal dewatering operations, the mounting ring 1 is fixed at the bottom of the foundation pit, keeping the entire dewatering construction structure stable. The drill pipe sleeve 2 is a hollow structure, forming a water collection area inside. The pumping pipe 3 is rotatably installed inside the drill pipe sleeve 2, and the diameter of the pumping pipe 3 is smaller than the inner diameter of the drill pipe sleeve 2. The pumping pipe 3 extends to the bottom of the drill pipe sleeve 2. Multiple seepage holes 21 are opened on the side wall of the drill pipe sleeve 2. Groundwater in the foundation pit enters the water collection area through the seepage holes 21 and is discharged through the pumping pipe 3, forming a water collection area inside the drill pipe sleeve 2. This enhances the overall strength and support capacity of the drill pipe sleeve 2. When used in easily pulverized red sandstone layers, the drill pipe sleeve 2 can effectively prevent borehole collapse, protect the safety and stability of the foundation pit, and ensure the smooth progress of drainage operations.

[0034] The drive mechanism is used to drive the drill pipe sleeve 2 to rotate. Since the water pumping pipe 3 is rotatably connected to the drill pipe sleeve 2, the circumferential positions of the mounting ring 1 and the water pumping pipe 3 remain unchanged. The rotation of the drill pipe sleeve 2 realizes drilling and drives the water pumping pipe 3 to move. When the foundation pit is excavated in layers, the drill pipe sleeve 2 and the water pumping pipe 3 continue to drill downward as the depth of the foundation pit increases. There is no need to interrupt the drainage process or pull the water pumping pipe 3 out of the sump. This simplifies the operation process, improves work efficiency, ensures that the foundation pit excavation and drainage operations are carried out simultaneously, and avoids the problem of water accumulation in the foundation pit caused by drainage interruption.

[0035] The mounting ring 1 has a support rod and two symmetrically installed positioning rods on its side. The positioning rods have through holes. During the rotation and drilling of the drill pipe sleeve 2, the drilling direction of the drill pipe sleeve 2 can be manually controlled by the support rods, and it is also convenient to apply pressure to the mounting ring 1 to provide sufficient drilling pressure to the drill pipe sleeve 2. When drainage is carried out after drilling, the mounting ring 1 is fixed by the through holes through the anchor rods to ensure the stability of the position of the mounting ring 1.

[0036] Reference Figure 2-4The drill pipe sleeve 2 includes an outer sleeve 22 and an inner liner 23. The inner wall of the outer sleeve 22 is in contact with the outer wall of the inner liner 23. The outer sleeve 22 and the inner liner 23 are coaxially rotatable. The bottom end of the outer sleeve 22 is conical and is equipped with a drill bit 24. The outer wall of the outer sleeve 22 is also equipped with a spiral conveying plate 25 connected to the drill bit 24. When the drill pipe sleeve 2 rotates as a whole, the drill bit 24 breaks the rock and the broken soil is conveyed upward along the spiral conveying plate 25 until it is discharged from the borehole. After reaching the borehole depth, the rotation of the drill pipe sleeve 2 can be stopped.

[0037] The seepage hole 21 penetrates the outer sleeve 22 and the inner liner 23, forming an outer hole 211 on the outer sleeve 22 and an inner hole 212 on the inner liner 23. When the outer hole 211 and the inner hole 212 coincide, the seepage hole 21 opens. When the outer hole 211 and the inner hole 212 are circumferentially misaligned, the seepage hole 21 closes.

[0038] A torsion structure is provided between the outer sleeve 22 and the inner liner 23. When the drill pipe sleeve 2 is drilling downward, the inner liner 23 is deflected to seal the seepage hole 21, preventing mud and sand from entering the interior of the drill pipe sleeve 2 under the action of drilling pressure. This avoids the contamination of the pumping pipe 3 and the water collection area by mud and sand, ensures the cleanliness of the water collection area, and reduces the cost of later maintenance and cleaning.

[0039] The drive mechanism includes a bevel gear 234 fixedly installed on the top of the inner liner tube 23, a motor 4 fixedly installed on the side of the mounting ring 1, and a bevel gear 41 fixedly installed at the output end of the motor 4. The bevel gear 234 meshes with the bevel gear 41. The motor 4 drives the bevel gear 41 to rotate, which in turn drives the bevel gear 234 to rotate, causing the inner liner tube 23 to rotate. The inner liner tube 23 transmits power through a torsion structure, driving the drill pipe sleeve 2 to drill downward as a whole.

[0040] Reference Figure 2 and 6 The torsion structure includes a rotating shaft 231 fixedly installed at the bottom of the inner liner tube 23, and a rotating hole 221 adapted to the rotating shaft 231 fixedly installed at the bottom of the outer sleeve tube 22. The rotating shaft 231 can rotate stably within the rotating hole 221. A torsion spring 26 is installed between the rotating shaft 231 and the inner wall of the outer sleeve tube 22. Under the action of the torsion spring 26, when the rotating shaft 231 and the outer sleeve tube 22 rotate relative to each other in the drilling direction, the torsion spring 26 will store elastic potential energy and restore the relative position of the inner liner tube 23 and the outer sleeve tube 22 after the inner liner tube 23 loses its driving force.

[0041] A limiting groove 222 is provided on the inner wall of the rotating hole 221. A limiting block 232, with a width smaller than the limiting groove 222, is provided on the portion of the rotating shaft 231 located within the rotating hole 221. Under the combined action of the limiting groove 222 and the limiting block 232, the relative rotation angle between the rotating shaft 231 and the rotating hole 221 is limited. When the drill rod sleeve 2 drills downwards, the motor 4 drives the inner liner tube 23 to rotate. Because the outer sleeve 22 is embedded in the soil and rock layer at the bottom of the pit and is subject to the resistance of the soil and rock layer, it cannot rotate directly. The inner liner tube 23 first rotates a certain angle, allowing the torsion spring 26 to store elastic potential energy. Simultaneously, the outer hole 211 and the inner hole 212 are misaligned, and the seepage hole 2... 1. The system is closed until the limit block 232 reaches the limit position of the limit groove 222. Then, the power of the rotating shaft 231 is applied to the outer sleeve 22, causing the outer sleeve 22 to rotate and realize drilling. During the drilling process, the seepage hole 21 is in a closed state, which avoids the pollution of the pumping pipe 3 and the water collection area by mud and sand. After the drilling is completed, the motor 4 is turned off and no longer provides power. The torsion spring 26 releases elastic potential energy, the inner liner 23 automatically resets, and the seepage hole 21 reopens, restoring the normal water collection and dewatering function. This realizes the automatic opening and closing of the seepage hole 21, simplifies the operation process, improves drainage efficiency, and ensures the stability and reliability of the foundation pit drainage.

[0042] Reference Figure 5 The water suction pipe 3 includes a suction section 31 and a connecting section 32. The suction section 31 is a rigid mesh pipe, and the connecting section 32 is a rigid round pipe. Both the suction section 31 and the connecting section 32 are made of stainless steel. The suction section 31 is located at the bottom inside the drill pipe sleeve 2. The connecting section 32 is connected to the top of the suction section 31 and extends out of the drill pipe sleeve 2. The extended part of the connecting section 32 is connected to a water pump for pumping water.

[0043] The suction section 31 has two bosses on both sides, and the inner liner 23 has two bosses on the side wall that restrict the axial movement of the bosses. The two bosses are located on the opposite side of the two bosses. The cooperation between the bosses ensures the stability of the pumping pipe 3 rotating inside the drill pipe sleeve 2.

[0044] The water absorption section 31 is covered with a sponge filter layer 33. A squeezing roller 233 is rotatably arranged between the two bosses. The squeezing roller 233 squeezes and deforms the sponge filter layer 33 at the corresponding position. The sponge filter layer 33 can effectively filter the pulverized red sandstone mud and prevent it from entering the pumping pipe 3. Since the foundation pit is excavated in layers, the drilling frequency of the drill sleeve 2 is consistent with the excavation frequency. Each time drilling, the squeezing roller 233 rotates around the water absorption section 31, so that the squeezing roller 233 rotates around the sponge filter layer 33 to squeeze, realizing the squeezing discharge and self-cleaning functions, reducing the frequency of replacement and maintenance.

[0045] Working principle:

[0046] The dewatering construction device is set vertically along the bottom edge of the foundation pit. For large-area foundation pits, multiple devices can be set at equal intervals. In the dewatering state, the drill rod sleeve 2 needs to be drilled downwards until the installation ring 1 is flush with the bottom surface of the foundation pit. The groundwater in the foundation pit enters the water collection area through the seepage hole 21 and is discharged through the pumping pipe 3. The sponge filter layer 33 can effectively filter the pulverized red sandstone mud and sand, preventing it from entering the pumping pipe 3.

[0047] During the layered excavation of the foundation pit, as the depth of the foundation pit increases, the drill pipe sleeve 2 and the pumping pipe 3 continuously drill downwards. The motor 4 is started, and the motor 4 drives the bevel gear 21 to rotate, which in turn drives the bevel gear 1 234 to rotate, causing the inner liner 23 to rotate. The inner liner 23 transmits power through the torsion structure, driving the drill pipe sleeve 2 to drill downwards as a whole.

[0048] Motor 4 drives the inner liner 23 to rotate. Because the outer liner 22 is embedded in the soil and rock layer at the bottom of the pit and is subject to the resistance of the soil and rock layer, it cannot rotate directly. The inner liner 23 first rotates a certain angle, so that the torsion spring 26 stores elastic potential energy. At the same time, the outer hole 211 and the inner hole 212 are misaligned, and the seepage hole 21 is closed. Until the limit block 232 reaches the limit position of the limit groove 222, the power of the rotating shaft 231 acts on the outer liner 22, so that the outer liner 22 rotates and realizes drilling. During the drilling process, the seepage hole 21 is in a closed state, which avoids the pollution of the pumping pipe 3 and the water collection area by mud and sand. After the drilling is completed, the motor 4 is turned off and no longer provides power. The torsion spring 26 releases elastic potential energy, the inner liner 23 automatically resets, and the seepage hole 21 reopens, restoring the normal water collection and dewatering function.

[0049] Each time drilling occurs, the extrusion roller 233 rotates around the water absorption section 31, causing the extrusion roller 233 to rotate around the sponge filter layer 33 to extrude and extrude sewage, thus achieving the functions of extrusion discharge and self-cleaning, reducing the frequency of replacement and maintenance.

Claims

1. A construction structure for dewatering foundation pits in red sandstone strata, characterized in that, Includes an installation ring (1), a drill pipe sleeve (2), a pumping pipe (3), and a drive mechanism, wherein: The top of the drill pipe sleeve (2) is rotatably connected to the mounting ring (1). The drill pipe sleeve (2) has a hollow structure, forming a water collection area inside the drill pipe sleeve (2). The pumping pipe (3) is rotatably installed inside the drill pipe sleeve (2), and the diameter of the pumping pipe (3) is smaller than the inner diameter of the drill pipe sleeve (2). The pumping pipe (3) extends to the bottom of the drill pipe sleeve (2). Multiple seepage holes (21) are opened on the side wall of the drill pipe sleeve (2). Groundwater in the foundation pit enters the water collection area through the seepage holes (21) and is discharged through the pumping pipe (3). The drive mechanism is used to drive the drill pipe sleeve (2) to rotate, so that the drill pipe sleeve (2) and the pumping pipe (3) can continuously drill downward as the depth of the foundation pit increases during the layered excavation of the foundation pit.

2. The construction structure for dewatering foundation pits in red sandstone strata according to claim 1, characterized in that, The drill pipe sleeve (2) includes an outer sleeve (22) and an inner liner (23). The outer sleeve (22) and the inner liner (23) are coaxially rotatable. The bottom end of the outer sleeve (22) is tapered and is provided with a drill bit (24). The outer wall of the outer sleeve (22) is also provided with a spiral conveying plate (25) connected to the drill bit (24). A torsion structure is provided between the outer sleeve (22) and the inner liner (23). When the drill pipe sleeve (2) drills downward, the inner liner (23) is deflected to seal the seepage hole (21).

3. The construction structure for dewatering foundation pits in red sandstone strata according to claim 2, characterized in that, The seepage hole (21) penetrates the outer sleeve (22) and the inner liner (23), forming an outer hole (211) on the outer sleeve (22) and an inner hole (212) on the inner liner (23). When the outer hole (211) and the inner hole (212) coincide, the seepage hole (21) is open. When the outer hole (211) and the inner hole (212) are circumferentially misaligned, the seepage hole (21) is closed.

4. The construction structure for dewatering foundation pits in red sandstone strata according to claim 2, characterized in that, The torsion structure includes a rotating shaft (231) fixedly installed at the bottom of the inner liner tube (23), a rotating hole (221) adapted to the rotating shaft (231) fixedly installed at the bottom of the outer sleeve tube (22), and a torsion spring (26) installed between the rotating shaft (231) and the inner wall of the outer sleeve tube (22). The inner wall of the rotating hole (221) is provided with a limiting groove (222), and the part of the rotating shaft (231) located in the rotating hole (221) is provided with a limiting block (232) with a width smaller than the limiting groove (222).

5. The construction structure for dewatering foundation pits in red sandstone strata according to claim 2, characterized in that, The pumping pipe (3) includes a suction section (31) and a connecting section (32). The suction section (31) is located at the bottom inside the drill pipe sleeve (2). The connecting section (32) is connected to the top of the suction section (31) and extends out of the drill pipe sleeve (2). The water absorption section (31) has two bosses on both sides, and the inner liner tube (23) has two bosses on the side wall that restrict the axial movement of the bosses.

6. The construction structure for dewatering foundation pits in red sandstone strata according to claim 5, characterized in that, The water-absorbing section (31) is covered with a sponge filter layer (33), and a squeezing roller (233) is rotatably arranged between the two bosses. The squeezing roller (233) squeezes and deforms the sponge filter layer (33) at the corresponding position.

7. The construction structure for dewatering foundation pits in red sandstone strata according to claim 2, characterized in that, The drive mechanism includes a bevel gear one (234) fixedly installed on the top of the inner liner tube (23), a motor (4) fixedly installed on the side of the mounting ring (1), and a bevel gear two (41) fixedly installed at the output end of the motor (4). The bevel gear one (234) meshes with the bevel gear two (41).

8. The construction structure for dewatering foundation pits in red sandstone strata according to claim 1, characterized in that, The mounting ring (1) has a support rod and two symmetrically installed positioning rods on its side, and the positioning rods have through holes.

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