Reconnaissance device for geophysical prospecting of geotechnical engineering

Abstract

The invention belongs to the technical field of electrical prospecting, and particularly relates to a prospecting device for geotechnical engineering geophysical prospecting, which comprises an electrode power supply, a signal acquisition device, a signal acquisition circuit, an MCU (Microprogrammed Control Unit) and an upper computer, the electrode power supply comprises a lithium battery, a digital boosting module and an inversion module; the signal acquisition circuit is used for realizing measurement of current, voltage and phase difference; the signal acquisition circuit comprises a current acquisition circuit, a voltage acquisition circuit, an AD acquisition module and a comparator module; the MCU is used for being connected with the inversion module, the AD acquisition module, the comparator module and the Raspberry Pi and realizing communication and control; and the upper computer comprises a Raspberry Pi, a touch screen, a 4G module and a USB (Universal Serial Bus) interface. A symmetrical square wave power supply with variable voltage and frequency is designed as an electrode power supply, resistivity measurement is carried out by using a four-electrode method, grounding resistance measurement is realized by using a frequency conversion method, the measurement precision of electrical parameters is improved, and the distortion degree of electrical prospecting is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of electrical prospecting, in particular to a prospecting device used for geotechnical engineering geophysical prospecting. Background Art

[0002] Electrical prospecting is a geophysical exploration technology that studies underground geological structures and resources by measuring the electrical parameters of underground media (such as resistivity and conductivity). It has a wide range of applications and can be used to discover the location of ore bodies and deposits, identify the location and depth of aquifers, evaluate groundwater resources, detect the distribution of underground pollutants, evaluate environmental impacts, provide geological information for underground engineering design, avoid potential geological risks, etc.

[0003] However, the existing technology often has the following defects: At present, electrical exploration equipment is easily affected by the surrounding environment during use, especially the measurement data obtained on site is prone to distortion during transmission, resulting in deviations in the final measurement results, and the output voltage of the power supply is not stable enough, which will also affect the data collection process.

[0004] To this end, the present invention provides a survey device for geotechnical engineering geophysical exploration. Summary of the invention

[0005] In order to make up for the deficiencies of the prior art, at least one technical problem raised in the background technology is solved.

[0006] The technical solution adopted by the present invention to solve the technical problem is: the survey device for geotechnical engineering geophysical prospecting described in the present invention comprises an electrode power supply, a signal acquisition device, a signal acquisition circuit, an MCU and a host computer;

[0007] The electrode power supply is used to supply power to the electrode; the electrode power supply includes a lithium battery, a digital boost module and an inverter module;

[0008] The signal acquisition device is used to lay out electrodes and apply a measuring current to the rock and soil;

[0009] The signal acquisition circuit is used to measure current, voltage and phase difference; the signal acquisition circuit includes a current acquisition circuit, a voltage acquisition circuit, an AD acquisition module and a comparator module;

[0010] The MCU is used to connect with the inverter module, the AD acquisition module, the comparator module and the Raspberry Pi to achieve communication and control;

[0011] The host computer is used to input instructions and output measurement results; the host computer includes RaspberryPi, a touch screen, a 4G module and a USB interface.

[0012] Preferably, it also includes a 5V voltage stabilizing module; the 5V voltage stabilizing module serves as a power management device, which adjusts the internal resistance and stably converts the voltage of the lithium battery into a 5V output voltage.

[0013] Preferably, the signal acquisition device includes a connecting seat and a cable; an electrode is fixedly connected to the lower side of the connecting seat; a conductor is arranged inside the connecting seat, and the conductor is electrically connected to the electrode; slide grooves are provided inside the connecting seat at both sides of the conductor; sockets are provided between the slide grooves and the outer side of the connecting seat; a conductive block is slidably connected inside the slide groove; a conductive spring is fixedly connected between the conductive block and the conductor; a connector is fixedly connected to the end of the cable; a conductive head is fixedly connected to the surface of the connector, and the conductive head is threadedly connected to the socket.

[0014] Preferably, a protective plate is fixedly connected to the surface of the connecting seat, and the protective plate is designed to be an arched structure.

[0015] Preferably, a pressing plate is sleeved on the outer side of the electrode; a telescopic member is fixedly connected between the connecting seat and the pressing plate; and the telescopic member is made of a water-swellable material.

[0016] Preferably, an outer telescopic cylinder and an inner telescopic cylinder are fixedly connected between the connecting seat and the pressure plate; the outer telescopic cylinder and the inner telescopic cylinder are formed by a group of cylinders with different diameters slidingly connected to each other; the electrode is located inside the inner telescopic cylinder, and the telescopic part is located between the outer telescopic cylinder and the inner telescopic cylinder; a group of through holes are evenly distributed on the surface of the outer telescopic cylinder.

[0017] Preferably, a group of water diversion blocks are evenly distributed around the pressure plate; the surface of the water diversion blocks is fixedly connected with a water diversion strip, and the other end of the water diversion strip passes through the outer telescopic cylinder and is connected to the telescopic member; the water diversion blocks and the water diversion strip are made of water-absorbing material.

[0018] Preferably, an air storage part is arranged inside the telescopic part; a push ring is arranged between the side of the conductive block close to the socket and the slide groove; the air storage part and the push ring are both designed as elastic hollow structures, and the air storage part and the push ring are connected to each other through a conduit.

[0019] Preferably, a flexible ring is fixedly connected to the inner side of the pressing plate, and the flexible ring and the electrode are in contact with each other.

[0020] Preferably, a sealing groove is opened inside the pressure plate; magnetic plates are slidably connected inside the sealing groove at both sides of the electrode, and a pair of magnetic plates attract each other; an elastic part is fixedly connected between the magnetic plate and the sealing groove; an elastic pad is fixedly connected to one end of the magnetic plate close to the electrode.

[0021] The beneficial effects of the present invention are as follows:

[0022] 1. The survey device for geotechnical engineering geophysical prospecting described in the present invention uses a symmetrical square wave power supply with variable voltage and frequency as an electrode power supply, uses a four-electrode method to measure resistivity, and uses a frequency conversion method to achieve ground resistance measurement, thereby improving the measurement accuracy of electrical parameters and reducing the distortion of electrical prospecting. At the same time, by setting a 5V voltage regulator module, the stability of the entire system during operation is guaranteed and the occurrence of overload is reduced.

[0023] 2. The survey device for geotechnical engineering geophysical prospecting described in the present invention, when connecting electrodes, align the conductive head at the end of the cable with the socket, screw it into the socket through the connecting head, and make the conductive head contact with the conductive block, and then the adjacent electrodes are electrically connected through the conductor, conductive spring, conductive block, conductive head and cable, which is convenient and quick, improves the series connection efficiency between electrodes, and reduces the workload of circuit connection.

[0024] 3. The survey device for geotechnical engineering geophysical prospecting described in the present invention, when it rains, the telescopic part absorbs water and expands and stretches, pushing the pressure plate downward and pressing it against the ground; as the telescopic part continues to expand, the connecting seat is lifted upward as a whole, thereby pulling the electrode out of the rock and soil, preventing the electrode from being immersed in the rock and soil filled with rainwater for a long time, reducing the corrosion phenomenon, and ensuring its measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described below in conjunction with the accompanying drawings.

[0026] Figure 1 It is a schematic diagram of the structure of the present invention;

[0027] Figure 2 It is a structural schematic diagram of the signal acquisition device in the present invention;

[0028] Figure 3 It is a structural schematic diagram of the connecting seat in the present invention;

[0029] Figure 4 It is a schematic diagram of the structure of the electrode in the present invention;

[0030] Figure 5 is a cross-sectional view of the signal acquisition device of the present invention;

[0031] Figure 6 yes Figure 5 A partial enlarged view of the middle part;

[0032] Figure 7 yes Figure 5 A partial enlarged view of point B in the middle.

[0033] In the figure: connecting seat 1, cable 2, electrode 3, conductor 4, slide groove 5, jack 6, conductive block 7, conductive spring 8, connector 9, conductive head 10, protective plate 11, pressure plate 12, telescopic member 13, outer telescopic cylinder 14, inner telescopic cylinder 15, water diversion block 16, water diversion strip 17, air storage member 18, push ring 19, flexible ring 20, blocking groove 21, magnetic plate 22, elastic member 23, elastic pad 24, conduit 25. DETAILED DESCRIPTION

[0034] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0035] like Figures 1 to 7 As shown, the survey device for geotechnical engineering geophysical prospecting described in the present invention includes an electrode power supply, a signal acquisition device, a signal acquisition circuit, an MCU and a host computer;

[0036] The electrode power supply is used to power the electrode 3; the electrode power supply includes a lithium battery, a digital boost module and an inverter module; the measurement of rock resistivity and ground resistance requires the use of an external power supply to power the rock to be measured, and the digital boost module is used to achieve a wide range of adjustable voltage, which is then converted into a symmetrical square wave through the inverter module to power the electrode 3;

[0037] The signal acquisition device is used to lay out the electrodes 3 and apply a measuring current to the rock and soil. The number of the signal acquisition devices is one group, preferably four;

[0038] The signal acquisition circuit is used to realize the measurement of current, voltage and phase difference; the signal acquisition circuit includes a current acquisition circuit, a voltage acquisition circuit, an AD acquisition module and a comparator module; the analog signal is acquired through the voltage and current acquisition circuits, and then the AD acquisition module is used to convert the analog signal into a digital signal, the comparator module converts the analog signal into a square wave signal, and then the MCU external interrupt and timer are used to realize the phase difference measurement.

[0039] The MCU is used to connect with the inverter module, AD acquisition module, comparator module and Raspberry Pi to achieve communication and control; the MCU communicates with the AD acquisition module through SPI to control and collect data for voltage and current measurement; the MCU captures the square wave signal output by the comparator module through external interrupts to achieve phase difference measurement; the MCU outputs a dual-channel anti-phase PWM wave to control the inverter module, and transmits configuration instructions and data through the UART and the upper computer graphical interface;

[0040] The host computer is used to input instructions and output measurement results; the host computer includes Raspberry Pi, a touch screen, a 4G module and a USB interface; the host computer graphical interface runs on the Raspberry Pi, and the user interacts with the MCU through the touch screen. After the data measurement is completed, the data can be copied out using a USB flash drive or transmitted to a private cloud through the 4G module.

[0041] It also includes a 5V voltage regulator module; the 5V voltage regulator module serves as a power management device, which adjusts the internal resistance and stably converts the voltage of the lithium battery into a 5V output voltage.

[0042] The present invention designs a symmetrical square wave power supply with variable voltage and frequency as an electrode power supply, uses a four-electrode 3 method to measure resistivity, and uses a frequency conversion method to achieve ground resistance measurement, thereby improving the measurement accuracy of electrical parameters and reducing the distortion degree of electrical exploration. At the same time, by setting a 5V voltage stabilizing module, the stability of the entire system during operation is guaranteed and the occurrence of overload is reduced.

[0043] As a preferred embodiment of the present invention, the signal acquisition device includes a connecting seat 1 and a cable 2; an electrode 3 is fixedly connected to the lower side of the connecting seat 1; a conductor 4 is arranged inside the connecting seat 1, and the conductor 4 is electrically connected to the electrode 3; a slide groove 5 is opened inside the connecting seat 1 at both sides of the conductor 4; a socket 6 is opened between the slide groove 5 and the outer side of the connecting seat 1; a conductive block 7 is slidably connected inside the slide groove 5; a conductive spring 8 is fixedly connected between the conductive block 7 and the conductor 4; a connector 9 is fixedly connected to the end of the cable 2; a conductive head 10 is fixedly connected to the surface of the connector 9, and the conductive head 10 is threadedly connected to the socket 6. When connecting the electrodes 3, align the conductive head 10 at the end of the cable 2 with the socket 6, screw it into the socket 6 through the connector 9, and make the conductive head 10 contact with the conductive block 7, so that the adjacent electrodes 3 are electrically connected through the conductor 4, the conductive spring 8, the conductive block 7, the conductive head 10 and the cable 2, which is convenient and quick, improves the series connection efficiency between the electrodes 3, and reduces the workload of circuit connection.

[0044] As a preferred embodiment of the present invention, a protective plate 11 is fixedly connected to the surface of the connection seat 1, and the protective plate 11 is designed to be an arched structure. By providing the protective plate 11, the electrode 3 is protected by its arched structure, the protective strength is improved, and the electrode 3 is prevented from being damaged by workers due to accidental stepping, and both sides of the arched protective plate 11 have openings, which can ensure sufficient heat dissipation effect and improve the working efficiency of the electrode 3.

[0045] As a preferred embodiment of the present invention, a pressing plate 12 is sleeved on the outer side of the electrode 3; a telescopic member 13 is fixedly connected between the connecting seat 1 and the pressing plate 12; the telescopic member 13 is made of a water-swellable material, such as expanded rubber, polymer hydrogel, etc.

[0046] Since electrical prospecting often requires multiple measurements at the same location to eliminate various interference factors, the measurement cycle is usually several days or even weeks. During this period, in order to save manpower and material resources, the electrode 3 will be retained in the rock and soil to facilitate measurement at any time. However, when it rains, rainwater will not only cause measurement errors, but the electrode 3 will be easily corroded and damaged due to long-term immersion in rainwater. At this time, when the present invention encounters rain, the telescopic part 13 absorbs water and expands and elongates, pushing the pressure plate 12 downward and pressing it to the ground. As the telescopic part 13 continues to expand, the connecting seat 1 is lifted upward as a whole, thereby pulling the electrode 3 out of the rock and soil, preventing the electrode 3 from being immersed in rock and soil full of rainwater for a long time, reducing its corrosion, and ensuring its measurement accuracy. In addition, the telescopic part 13 can be reused, and it can shrink to a normal state when the moisture inside it gradually dries.

[0047] An outer telescopic cylinder 14 and an inner telescopic cylinder 15 are fixedly connected between the connecting seat 1 and the pressing plate 12; the outer telescopic cylinder 14 and the inner telescopic cylinder 15 are formed by a group of cylinders with different diameters slidingly connected to each other; the electrode 3 is located inside the inner telescopic cylinder 15, and the telescopic member 13 is located between the outer telescopic cylinder 14 and the inner telescopic cylinder 15; the surface of the outer telescopic cylinder 14 is evenly distributed with a group of through holes, which are used for rainwater to pass through and contact the telescopic member 13. By setting the outer telescopic cylinder 14 and the inner telescopic cylinder 15, the telescopic member 13 is restricted inside the two. When the telescopic member 13 expands and stretches, the outer telescopic cylinder 14 and the inner telescopic cylinder 15 are also extended synchronously, thereby blocking the side of the telescopic member 13, preventing the telescopic member 13 from expanding to the side, ensuring its extension amplitude in the up and down directions, and improving the efficiency of pulling the electrode 3 out of the rock and soil.

[0048] As a preferred embodiment of the present invention, a group of water diversion blocks 16 are evenly distributed around the pressure plate 12; the surface of the water diversion blocks 16 is fixedly connected with a water diversion strip 17, and the other end of the water diversion strip 17 passes through the outer telescopic cylinder 14 and is connected to the telescopic member 13; the water diversion blocks 16 and the water diversion strip 17 are made of absorbent materials, such as cotton, sponge, absorbent cloth, etc.

[0049] Since the telescopic member 13 is located between the outer telescopic cylinder 14 and the inner telescopic cylinder 15 and is separated from the ground by the pressure plate 12, the telescopic member 13 can only come into contact with water when it rains only when the nearby water level reaches a certain height, which will delay the expansion process of the telescopic member 13. At this time, a water guide block 16 and a water guide bar 17 are provided, and the water guide block 16 is directly placed on the ground. When it rains, rainwater can quickly come into contact with the water guide block 16 and be absorbed by it, and then the moisture is conducted to the telescopic member 13 through the water guide bar 17, prompting the telescopic member 13 to quickly absorb water and expand, thereby further improving the extraction efficiency of the electrode 3.

[0050] As a preferred embodiment of the present invention, an air storage member 18 is provided inside the telescopic member 13; a push ring 19 is provided between the side of the conductive block 7 close to the socket 6 and the slide slot 5; the air storage member 18 and the push ring 19 are both designed as elastic hollow structures, and the air storage member 18 and the push ring 19 are interconnected through a conduit 25. As the telescopic member 13 gradually expands, the air storage member 18 will be squeezed, and the air inside the air storage member 18 will be squeezed into the push ring 19 through the conduit 25, causing the push ring 19 to inflate and push the conductive block 7 to move inside the slide slot 5, thereby separating the conductive block 7 from the conductive head 10, cutting off the entire circuit, and preventing short circuits caused by local water leakage during rain, which may cause the entire system to be damaged, thereby powering off the various electrodes 3 and devices in the system and extending their service life.

[0051] As a preferred embodiment of the present invention, a flexible ring 20 is fixedly connected to the inner side of the pressing plate 12, and the flexible ring 20 fits with the electrode 3. By providing the flexible ring 20, when the electrode 3 is pulled upward, the flexible ring 20 can rub and scrape the side of the electrode 3, thereby wiping off the mud and water adhering to the surface of the electrode 3, further reducing the corrosion of rainwater, and improving the cleanliness of the electrode 3, preventing mud and water from hardening on its surface and affecting its next insertion into the rock and soil.

[0052] As a preferred embodiment of the present invention, a plugging groove 21 is provided inside the pressing plate 12; magnetic plates 22 are slidably connected inside the plugging groove 21 at both sides of the electrode 3, and the pair of magnetic plates 22 attract each other; an elastic member 23 is fixedly connected between the magnetic plate 22 and the plugging groove 21; an elastic pad 24 is fixedly connected to one end of the magnetic plate 22 close to the electrode 3. After the electrode 3 is completely pulled out and the lower end of the electrode 3 passes over the pressing plate 12, the pair of magnetic plates 22 approach each other and close together under the action of magnetic attraction, thereby sealing the pressing plate 12, placing the electrode 3 in a relatively independent environment, further preventing rainwater from entering and contacting the electrode 3, and improving the protection effect on the electrode 3. By setting the elastic pads 24 to fit each other, the sealing degree of the pressing plate 12 can be improved.

[0053] The above-mentioned front, back, left, right, top and bottom are all based on the figures in the specification. Figure 1 As a benchmark, according to the person's observation perspective, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0054] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the scope of protection of the present invention.

[0055] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A survey device for geotechnical engineering geophysical exploration, characterized in that: It includes an electrode power supply, a signal acquisition device, a signal acquisition circuit, an MCU and a host computer; The electrode power supply is used to supply power to the electrode (3); the electrode power supply comprises a lithium battery, a digital boost module and an inverter module; The signal acquisition device is used to lay out electrodes (3) and apply a measuring current to the rock and soil; The signal acquisition circuit is used to measure current, voltage and phase difference; the signal acquisition circuit includes a current acquisition circuit, a voltage acquisition circuit, an AD acquisition module and a comparator module; The MCU is used to connect with the inverter module, the AD acquisition module, the comparator module and the Raspberry Pi to achieve communication and control; The host computer is used to input instructions and output measurement results; the host computer includes RaspberryPi, a touch screen, a 4G module and a USB interface.

2. The exploration device for geotechnical engineering geophysical exploration according to claim 1, characterized in that: It also includes a 5V voltage regulator module; the 5V voltage regulator module serves as a power management device, which adjusts the internal resistance and stably converts the voltage of the lithium battery into a 5V output voltage.

3. The exploration device for geotechnical engineering geophysical exploration according to claim 1, characterized in that: The signal acquisition device comprises a connection seat (1) and a cable (2); an electrode (3) is fixedly connected to the lower side of the connection seat (1); a conductor (4) is arranged inside the connection seat (1), and the conductor (4) is electrically connected to the electrode (3); a slide groove (5) is provided inside the connection seat (1) at both sides of the conductor (4); a plug hole (6) is provided between the slide groove (5) and the outer side of the connection seat (1); a conductive block (7) is slidably connected inside the slide groove (5); a conductive spring (8) is fixedly connected between the conductive block (7) and the conductor (4); a connector (9) is fixedly connected to the end of the cable (2); a conductive head (10) is fixedly connected to the surface of the connector (9), and the conductive head (10) is threadedly connected to the plug hole (6).

4. The exploration device for geotechnical engineering geophysical exploration according to claim 3, characterized in that: A protective plate (11) is fixedly connected to the surface of the connection seat (1), and the protective plate (11) is designed to be an arched structure.

5. The exploration device for geotechnical engineering geophysical exploration according to claim 3, characterized in that: A pressing plate (12) is sleeved on the outside of the electrode (3); a telescopic member (13) is fixedly connected between the connecting seat (1) and the pressing plate (12); and the telescopic member (13) is made of a water-swellable material.

6. The exploration device for geotechnical engineering geophysical exploration according to claim 5, characterized in that: An outer telescopic cylinder (14) and an inner telescopic cylinder (15) are fixedly connected between the connecting seat (1) and the pressing plate (12); the outer telescopic cylinder (14) and the inner telescopic cylinder (15) are both formed by a group of cylinders with different diameters that are slidably sleeved together; the electrode (3) is located inside the inner telescopic cylinder (15), and the telescopic member (13) is located between the outer telescopic cylinder (14) and the inner telescopic cylinder (15); and a group of through holes are evenly distributed on the surface of the outer telescopic cylinder (14).

7. The exploration device for geotechnical engineering geophysical exploration according to claim 6, characterized in that: A group of water guide blocks (16) are evenly distributed around the pressure plate (12); a water guide strip (17) is fixedly connected to the surface of each water guide block (16), and the other end of the water guide strip (17) passes through the outer telescopic cylinder (14) and is connected to the telescopic member (13); the water guide block (16) and the water guide strip (17) are both made of water-absorbing material.

8. The exploration device for geotechnical engineering geophysical exploration according to claim 5, characterized in that: An air storage member (18) is arranged inside the telescopic member (13); a push ring (19) is arranged between the side of the conductive block (7) close to the insertion hole (6) and the slide groove (5); the air storage member (18) and the push ring (19) are both designed to be elastic hollow structures, and the air storage member (18) and the push ring (19) are connected to each other through a conduit (25).

9. The exploration device for geotechnical engineering geophysical exploration according to claim 5, characterized in that: A flexible ring (20) is fixedly connected to the inner side of the pressing plate (12), and the flexible ring (20) and the electrode (3) are in contact with each other.

10. The survey device for geotechnical engineering geophysical exploration according to claim 6, characterized in that: A blocking groove (21) is provided inside the pressing plate (12); magnetic plates (22) are slidably connected inside the blocking groove (21) at positions on both sides of the electrode (3), and the pair of magnetic plates (22) attract each other; an elastic member (23) is fixedly connected between the magnetic plate (22) and the blocking groove (21); and an elastic pad (24) is fixedly connected to one end of the magnetic plate (22) close to the electrode (3).

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