Auxiliary waterproof device for measuring underground water level of sea area drill hole

Abstract

The utility model relates to the technical field of offshore wind power engineering geological survey, in particular to an auxiliary waterproof device for measuring the underground water level of a sea area drill hole, a drill hole is vertically and downwards drilled in the seabed, the drill hole downwards extends into a diving soil layer or a confined water soil layer, the auxiliary waterproof device comprises a casing pipe and a well pipe, the casing pipe is vertically inserted into the drill hole, and the well pipe is arranged in the casing pipe. The top of the casing pipe penetrates out of the sea surface, the bottom of the casing pipe is located in a waterproof soil layer on the upper portion of the diving soil layer or a waterproof soil layer on the upper portion of the confined water soil layer, the well pipe axially penetrates through the casing pipe and is located at the bottom of the drill hole, and a plurality of liquid inlet filter holes are formed in the bottom of the well pipe in the circumferential direction. According to the auxiliary water insulation device, hydraulic connection between seawater and underground water in the drill hole is isolated independently through the casing pipe, hydraulic connection between diving and confined water in the drill hole can be achieved through cooperation of the casing pipe and the well casing, and therefore existing offshore wind power exploration equipment can accurately obtain diving data and confined water data of the underground water.

Description

Technical Field

[0001] The utility model relates to the technical field of geological survey for offshore wind power engineering, and in particular to an auxiliary water-isolating device for measuring underground water level in sea boreholes. Background Art

[0002] With the rapid development of the offshore wind power industry, various types of wind turbine foundations have been continuously updated and optimized. Since various types of groundwater, such as phreatic water and confined water, are often found in the bottom structure of the sea area, it is an important part of the design process for the wind turbine foundation to identify the hydrogeological conditions of the groundwater at the proposed site. Therefore, when conducting geological surveys for offshore wind power foundations, how to accurately measure the water levels of phreatic water and confined water in the sea borehole is of great significance for evaluating the impact of groundwater on the design and construction of wind turbine foundations.

[0003] The key to accurately measuring the groundwater level in a borehole in the sea area is how to block the hydraulic connection between seawater and groundwater. At present, the commonly used technical means for groundwater exploration in geological surveys for offshore wind power foundation projects is mainly drilling holes with a drilling rig, specifically using casing to isolate the hydraulic connection between seawater and groundwater in the borehole, and then observing the groundwater level in the borehole.

[0004] However, the existing technical means have the following defects: 1. The casing used for water isolation is often made of multiple sections of steel pipes connected by threads. Due to the strong winds and waves in the sea area, the steel pipes are easily swayed by the water flow and waves. The threaded connections of each casing cannot be completely sealed and watertight. Seawater can easily penetrate into the casing along the threaded connections, and the actual water isolation effect is difficult to guarantee. 2. Measures are only taken to isolate the hydraulic connection between seawater and borehole groundwater, but not to isolate the hydraulic connection between groundwater and pressurized water in the borehole, resulting in the measured water level being a mixed water level of groundwater and pressurized water in the borehole, and it is impossible to accurately measure the groundwater level and pressurized water level. Utility Model Content

[0005] In order to solve the above technical problems, the utility model provides an auxiliary water-isolating device for measuring groundwater level in sea boreholes, which is helpful for accurately obtaining groundwater diving data and confined water data.

[0006] The utility model adopts the following technical solutions:

[0007] The utility model provides an auxiliary water-blocking device for measuring underground water levels in sea areas through boreholes. A borehole is drilled vertically downward on the seabed, and the borehole extends downward to a phreatic soil layer or a confined water-soil layer. The device comprises a casing and a well pipe. The casing is vertically inserted in the borehole, and the top of the casing passes through the sea surface, and the bottom is located in a water-blocking soil layer above the phreatic soil layer or in a water-blocking soil layer above the confined water-soil layer. The well pipe is axially penetrated in the casing and is located at the bottom of the borehole, and a plurality of liquid inlet filter holes are circumferentially opened at the bottom of the well pipe.

[0008] Preferably, the sleeve comprises a plurality of cylindrical steel pipes and a plurality of water stop rings, the plurality of cylindrical steel pipes are axially threadedly connected in sequence, and a water stop ring is sleeved at the threaded connection of two adjacent cylindrical steel pipes.

[0009] Preferably, the cylindrical steel pipe used on the casing is a seamless steel pipe.

[0010] Preferably, the water stop ring is a water-swellable rubber ring, which is glued to the threaded connection.

[0011] Preferably, the well pipe includes a steel flower pipe and multiple cylindrical steel pipes. The circumferential pipe wall of the steel flower pipe is provided with multiple liquid inlet filter holes penetrating the inner and outer walls. The multiple cylindrical steel pipes are axially threadedly connected in sequence to form the well pipe body. The steel flower pipe is axially threadedly connected to the bottom of the well pipe body.

[0012] Preferably, the cylindrical steel pipe used on the well pipe is a seamless steel pipe.

[0013] Preferably, it also includes an airbag assembly and a pressure control assembly. The airbag assembly is circumferentially arranged on the outer wall of the well pipe near the bottom, and the pressure control assembly is arranged above the sea surface and communicated with the airbag assembly.

[0014] Compared with the prior art, the beneficial effects of the utility model are:

[0015] When the auxiliary water-blocking device for measuring the groundwater level in a sea area borehole of the utility model is used, the first drilling is performed vertically downward to the seabed by a drilling rig in the manner of following the pipe drilling. When the drilling reaches a certain depth in the relative water-blocking layer above the phreatic layer or the confined water layer where the water level needs to be measured, the following of the pipe is stopped to keep the top of the casing above the sea surface and the bottom in the relative water-blocking layer above the phreatic layer or the relative water-blocking layer above the confined water layer. The water-stop ring serves to block the possibility of seawater seeping into the borehole through the bottom of the casing. The second drilling is performed by the drilling rig. When the drilling reaches a certain depth in the phreatic layer or the confined water layer, the well pipe is axially inserted into the casing and the bottom of the well pipe is located at the bottom of the borehole. The pressure control component is started to expand the airbag to block the gap between the casing and the well pipe. Then the mixed water in the well pipe is pumped out. After the water level in the well pipe is stable, the water level inside the well pipe is the phreatic water level or the confined water level of the groundwater.

[0016] Obviously, the auxiliary water-isolating device for measuring groundwater level in sea boreholes of the utility model not only isolates the hydraulic connection between seawater and groundwater in the borehole through casing, but also can realize the hydraulic connection between diving water and pressurized water in the borehole through the cooperation of casing and well pipe, thereby helping existing offshore wind power exploration equipment to accurately obtain diving water data and pressurized water data of groundwater. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of an auxiliary water-isolating device for measuring groundwater level in a sea borehole in an embodiment of the utility model.

[0018] Figure 2 It is a structural diagram of the upper casing of the auxiliary water-blocking device for measuring the groundwater level in a sea borehole in an embodiment of the utility model.

[0019] Figure 3 It is a structural diagram of the upper well pipe of the auxiliary water-blocking device for measuring the groundwater level in a sea borehole in an embodiment of the utility model.

[0020] Figure 4 This is a state diagram of an auxiliary water-isolating device for measuring groundwater level in a sea borehole in an embodiment of the utility model working in a phreatic soil layer.

[0021] Figure 5 It is a state diagram of the auxiliary water-blocking device for measuring the groundwater level in a sea borehole in an embodiment of the utility model working in a confined water-soil layer.

[0022] The reference numerals are described as follows:

[0023] 1. Casing 22, well pipe body

[0024] 11. Water stop ring 3. Liquid inlet filter hole

[0025] 2. Well pipe 4. Air bag assembly

[0026] 21. Steel flower tube 5. Pressure control component DETAILED DESCRIPTION

[0027] The following is a further detailed description of the specific implementations of the present invention in conjunction with the accompanying drawings. These implementations are only used to illustrate the present invention, but not to limit the present invention.

[0028] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0029] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0030] In addition, in the description of the present invention, unless otherwise specified, “plurality” means two or more.

[0031] See also Figure 1 The present embodiment provides an auxiliary waterproofing device for measuring groundwater level in sea boreholes. A borehole is drilled vertically downward on the seabed, and the borehole extends downward to a phreatic soil layer or a confined water-soil layer, including a casing 1 and a well pipe 2. The casing 1 is vertically inserted in the borehole, and the top of the casing 1 passes through the sea surface, and the bottom is located in a waterproofing soil layer above the phreatic soil layer or in a waterproofing soil layer above the confined water-soil layer. The well pipe 2 is axially penetrated in the casing 1 and is located at the bottom of the borehole, and a plurality of liquid inlet filter holes 3 are circumferentially opened at the bottom of the well pipe 2.

[0032] Combination Figure 4 and Figure 5 When the auxiliary waterproofing device for measuring the groundwater level in a sea area borehole of this embodiment is used, the drilling rig is first used to drill a hole vertically downward toward the seabed for the first time, so that the borehole can extend downward to the water-proof soil layer above the phreatic soil layer or the water-proof soil layer above the confined water-soil layer; then the casing 1 is vertically inserted into the borehole, and the top of the casing 1 is kept out of the sea surface, and the bottom is located in the water-proof soil layer above the phreatic soil layer or the water-proof soil layer above the confined water-soil layer; then the drilling rig is used to drill a hole vertically downward toward the seabed for the second time, so that the borehole can extend downward to the phreatic soil layer or the confined water-soil layer; finally, the well pipe 2 is axially inserted into the casing 1, and the bottom of the well pipe 2 is located at the bottom of the borehole, and then the mixed water inside the casing 2 is pumped out. After the level is stable, the water level inside the well pipe 2 is the phreatic water level or the confined water level of the groundwater.

[0033] Obviously, the auxiliary water-isolating device for measuring the groundwater level in the sea borehole of this embodiment not only isolates the hydraulic connection between seawater and groundwater in the borehole through the casing 1, but also can realize the hydraulic connection between the diving water and pressurized water in the borehole through the cooperation of the casing 1 and the well pipe 2, thereby helping the existing offshore wind power exploration equipment to accurately obtain the diving water data and pressurized water data of the groundwater.

[0034] Preferably, see Figure 2The casing 1 includes a plurality of cylindrical steel pipes and a plurality of water stop rings 11. The plurality of cylindrical steel pipes are axially threadedly connected in sequence, and a water stop ring 11 is sleeved at the threaded connection of two adjacent cylindrical steel pipes. The setting of the water stop ring 11 can seal the gap at the threaded connection of two adjacent cylindrical steel pipes, thereby preventing seawater from penetrating into the casing 1 along the threaded connection between the cylindrical steel pipes, and effectively isolating the hydraulic connection between seawater and groundwater in the borehole.

[0035] Preferably, in this embodiment, the outer diameter of the cylindrical steel pipe on the casing 1 and the inner diameter of the water stop ring 11 are both 146 mm, and the inner diameter of the well pipe 2 is 89 mm.

[0036] Preferably, the cylindrical steel pipe used on the casing 1 is a seamless steel pipe.

[0037] Preferably, the water stop ring 11 is a water-swellable rubber ring, which is glued to the threaded connection. The water-swellable rubber ring is easy to swell after contacting water, thereby further strengthening the sealing effect of the threaded connection through expansion.

[0038] Preferably, see Figure 3 The well pipe 2 includes a steel flower pipe 21 and multiple cylindrical steel pipes. The circumferential pipe wall of the steel flower pipe 21 is provided with multiple liquid inlet filter holes 3 that penetrate the inner and outer walls. The multiple cylindrical steel pipes are axially threadedly connected in sequence to form a well pipe body 22. The steel flower pipe 21 is axially threadedly connected to the bottom of the well pipe body 22.

[0039] The steel flower pipe 21 has a plurality of liquid inlet filter holes 33 that penetrate the inner and outer walls distributed on the circumferential pipe wall, so that groundwater can enter the well pipe 2 along the liquid inlet filter holes 3. Therefore, when measuring the water level, the well pipe 2 can be used as an observation well pipe, and the existing water level measuring equipment can be inserted into the well pipe 2 to achieve water level measurement.

[0040] Preferably, the cylindrical steel pipe used in the well pipe 2 is a seamless steel pipe.

[0041] Preferably, see Figure 1 and Figure 3 The auxiliary water-blocking device for measuring the groundwater level in sea boreholes also includes an airbag assembly 4 and a pressure control assembly 5. The airbag assembly 4 is circumferentially arranged on the outer wall of the well pipe 2 near the bottom, and the pressure control assembly 5 is arranged above the sea surface and is connected to the airbag assembly 4.

[0042] When using the auxiliary waterproofing device for measuring the groundwater level in sea boreholes of this embodiment for auxiliary waterproofing, if the bottom of the well pipe 2 is located in the submerged soil layer, since the depth of the submerged soil layer is relatively small, the casing 1 alone can effectively cut off the hydraulic connection between seawater and groundwater; and when the bottom of the well pipe 2 is located in the confined water-soil layer, since the depth of the confined water-soil layer is relatively large, in order to prevent the casing 1 from being affected by the water pressure and causing water seepage from the outside to the inside, it is necessary to inflate and pressurize the airbag component 4 through the pressure control component 5. After being inflated and pressurized, the airbag component 4 expands and comes into close contact with the wall of the borehole, thereby achieving waterproofing, preventing the seawater that has penetrated into the casing 1 from mixing with the confined water and affecting the measurement accuracy of the confined water data.

[0043] The process of using the auxiliary water-blocking device for measuring groundwater level in sea boreholes of this embodiment to assist in measuring groundwater level is as follows: Figures 1 to 5 : First, the spatial distribution characteristics of the site's phreatic soil layer, confined water-soil layer and relatively impermeable soil layers are determined based on the analysis of the site's geological survey data; then, a drilling rig is used to drill a hole vertically downward to the seabed for the first time, so that the borehole can extend downward to the impermeable soil layer above the phreatic soil layer or the impermeable soil layer above the confined water-soil layer; then, the casing 1 is vertically inserted into the borehole, and the top of the casing 1 is kept out of the sea surface, while the bottom is located in the impermeable soil layer above the phreatic soil layer or the impermeable soil layer above the confined water-soil layer; then, a second drilling is performed vertically downward to the seabed by the drilling rig, so that the borehole can extend downward to the phreatic soil layer or the confined water-soil layer; then, the well pipe 2 is axially inserted into the casing 1, and the bottom of the well pipe 2 is located at the bottom of the borehole, and the mixed water inside the casing 2 is pumped out. After the water level stabilizes, the water level inside the well pipe 2 is the phreatic water level or the confined water level of the groundwater.

[0044] In addition, when the water level inside the well pipe 2 is the phreatic water level of the groundwater, it is only necessary to place the steel flower pipe 21 in the corresponding phreatic soil layer, and there is no need to open the pressure control component 5 to inflate and pressurize the airbag component 4, so as to measure the groundwater level of the sea borehole in accordance with relevant specifications; and when the water level inside the well pipe 2 is the confined water level of the groundwater, while placing the steel flower pipe 21 in the corresponding confined water and soil layer, it is also necessary to open the pressure control component 5 to inflate and pressurize the airbag component 4, and then measure the groundwater level of the sea borehole in accordance with relevant specifications.

[0045] Obviously, the auxiliary water-isolating device for measuring the groundwater level in the sea borehole of this embodiment has a simple structure, can effectively isolate the hydraulic connection between seawater and groundwater in the borehole, and the hydraulic connection between the submerged water in the borehole and the confined water, and achieve the purpose of accurately measuring the groundwater level in the borehole. The device is highly operable, low-cost, and can be widely used in the field of geological survey technology for offshore wind power engineering.

[0046] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the protection scope of the present invention.

Claims

1. An auxiliary water-blocking device for measuring the groundwater level in a sea area, wherein a borehole is vertically drilled downward on the seabed, and the borehole extends downward to a phreatic layer or a confined water layer, and is characterized in that: The invention comprises a casing (1) and a well pipe (2), wherein the casing (1) comprises a plurality of cylindrical steel pipes and a plurality of water stop rings (11), wherein the plurality of cylindrical steel pipes are axially threadedly connected in sequence, and a water stop ring (11) is sleeved on the threaded connection between two adjacent cylindrical steel pipes, wherein the casing (1) is vertically inserted into the borehole, and the top of the casing (1) passes through the sea surface, and the bottom is located in the water-proof soil layer above the phreatic soil layer or in the water-proof soil layer above the confined water soil layer, wherein the well pipe (2) is axially inserted into the casing (1) and is located at the bottom of the borehole, and a plurality of liquid inlet filter holes (3) are circumferentially opened at the bottom of the well pipe (2).

2. The auxiliary water-blocking device for measuring the groundwater level in a sea borehole according to claim 1 is characterized in that: The cylindrical steel pipe used on the casing (1) is a seamless steel pipe.

3. The auxiliary water-blocking device for measuring groundwater level in sea boreholes according to claim 1 is characterized in that: The water stop ring (11) is a water-swellable rubber ring, and the water-swellable rubber ring is glued to the threaded connection.

4. The auxiliary water-blocking device for measuring groundwater level in sea boreholes according to claim 1, characterized in that: The well pipe (2) comprises a steel flower pipe (21) and a plurality of cylindrical steel pipes; a plurality of liquid inlet filter holes (3) penetrating the inner and outer walls are distributed on the circumferential pipe wall of the steel flower pipe (21); the plurality of cylindrical steel pipes are axially threadedly connected in sequence to form a well pipe body (22); the steel flower pipe (21) is axially threadedly connected to the bottom of the well pipe body (22).

5. The auxiliary water-blocking device for measuring groundwater level in sea boreholes according to claim 4, characterized in that: The cylindrical steel pipe used in the well pipe (2) is a seamless steel pipe.

6. The auxiliary water-blocking device for measuring groundwater level in sea boreholes according to claim 1, characterized in that: It also includes an airbag assembly (4) and a pressure control assembly (5), wherein the airbag assembly (4) is circumferentially arranged on the outer wall of the well pipe (2) near the bottom, and the pressure control assembly (5) is arranged above the sea surface and is connected to the airbag assembly (4).

Images