Static sounding probe, static sounding device and static sounding method

Abstract

The invention discloses a static sounding probe, a static sounding device and a static sounding method, and relates to the technical field of static sounding, the static sounding probe comprises a probe system, an inner pipe and an outer pipe used for being in transmission connection with a rotary drilling system, the probe system is connected with the inner pipe, and a probe of the probe system extends out of the end, away from the rotary drilling system, of the outer pipe. The inner pipe is connected into the outer pipe through a bearing, and the outer pipe rotates while the inner pipe is static during drilling; the rotary drilling system applies rotary drilling power to the outer pipe and can apply vertical static pressure to the inner pipe at the same time, static sounding is conducted while drilling is conducted, the friction force of soil to the rotary drilling system and the outer pipe is reduced, it is ensured that a probe can conduct continuous penetration under certain pressure, and the drilling efficiency is improved. The continuous static sounding operation can be realized; meanwhile, due to the design that the probe extends out, it can be guaranteed that the probe is not disturbed by drilling of the outer pipe in the static sounding operation process, and the authenticity of the testing result is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of static cone penetration technology, and in particular to a static cone penetration probe, a static cone penetration device, and a static cone penetration method. Background Technology

[0002] In geotechnical engineering, accurately obtaining the physical and mechanical properties of foundation soil is crucial for the safety and stability of projects. Static cone penetration testing (PCT), as an efficient and reliable in-situ testing technique, can continuously measure parameters such as penetration resistance, side friction, and pore water pressure in strata like cohesive soil, silt, and sand without disturbing the soil mass, thereby inferring soil properties. It has been widely used in engineering. However, its application is also subject to some limitations. The most significant limitation is when the PCT probe encounters hard strata. During penetration, the hard strata exert significant resistance on the probe, limiting the penetration depth. This necessitates either terminating the test or retrieving the PCT equipment, followed by drilling to clear the hole and penetrate the hard strata before resuming the static cone penetration test.

[0003] With the continuous development of marine resources, such as the construction of large-scale marine engineering projects like offshore wind farms, cross-sea bridges, subsea tunnels, and offshore oil platforms, higher demands are being placed on the accuracy and efficiency of marine geological exploration. Marine static cone penetration testing (CPT) technology has emerged as a key method for obtaining parameters of marine foundation soil.

[0004] Currently, there are two main types of marine static cone penetration tests: seabed type and downhole type. Seabed type static cone penetration test is the basic type of marine static cone penetration test. Its core characteristics are "autonomous bottom stabilization and independent penetration operation". It does not rely on external carriers and can directly explore the seabed strata in a wide sea area. It is one of the core equipment for conventional deep-sea geological exploration.

[0005] Its technical features include: strong autonomous stability: relying on the weight and structural design of the base, the equipment can sit stably on the seabed without external support. Even in marine environments with current speeds ≤2m / s and wave heights ≤3m, it can maintain a vertical deviation of ≤1°, ensuring the accuracy of the data. It does not rely on external carriers such as ROVs or mother ships, reducing dependence on the operating platform. At the same time, the equipment does not need to maintain close contact with the mother ship (data is transmitted remotely via acoustics in the deep sea). A single unit can complete survey operations at multiple points in a large sea area, making it particularly suitable for geological surveys of large areas such as offshore wind farms and submarine pipelines, offering high operational flexibility.

[0006] However, it also has significant limitations: due to its own weight and penetration force, the penetration depth is usually ≤50m, which is difficult to meet the needs of deep strata exploration; in areas with a large slope (>15°) on the seabed, the base is prone to tilting, which leads to deviation of the penetration path and data distortion; the initial research and development and purchase costs of the equipment are high, and the maintenance is difficult, which makes it difficult for small and medium-sized exploration companies to popularize it.

[0007] Downhole static cone penetration testing (also known as borehole static cone penetration testing) is a type of technology that "relies on a borehole channel to achieve fine exploration of the formation." It requires first forming a borehole in the seabed or terrestrial rock formation using drilling equipment, and then placing the penetration probe into the borehole for penetration testing. Its core advantage is that it can accurately explore deep and hard formations, filling the technical gap of conventional cone penetration testing equipment that "stops when encountering hardness."

[0008] Its operation process needs to be coordinated with drilling operations: First, a borehole is formed in the target area using marine drilling equipment (such as a drilling rig mounted on a jack-up platform), and the drilling depth is determined according to the exploration requirements; after drilling is completed, the rock cuttings and mud in the borehole are cleaned, and the miniature probe of the downhole static cone penetration test is connected to the drill pipe through the drill pipe adapter unit and slowly lowered into the borehole; after reaching the predetermined depth, the pushing system is activated to push the probe into the formation at the bottom of the borehole, while the ground control unit collects and analyzes data in real time; after the exploration in a single borehole is completed, the probe is retrieved, the drilling equipment is moved to the next point, and the above process is repeated.

[0009] Downhole static cone penetration testing can overcome the penetration depth limitations of conventional cone penetration testing equipment, enabling precise testing of deep seabed rock strata and obtaining mechanical parameters of deep strata, providing key data for the basic design of large-scale marine engineering projects such as cross-sea bridges and subsea tunnels.

[0010] However, downhole static cone penetration testing is highly dependent on drilling: drilling must be completed before penetration testing can be carried out, the operation process is complex, the exploration cycle is long, the drilling cost is high, and the equipment needs to work in conjunction with drilling equipment.

[0011] Therefore, there is an urgent need for a static cone penetration tester that can perform static cone penetration tests while drilling, so as to achieve continuous static cone penetration tests. Summary of the Invention

[0012] The purpose of this invention is to provide a static cone penetration probe, a static cone penetration device, and a static cone penetration method to solve the problems existing in the prior art. By utilizing the characteristics that the outer tube is driven to rotate by the rotary drilling system and the inner tube is not affected by the rotation of the outer tube, static cone penetration can be performed while drilling, enabling continuous static cone penetration operations.

[0013] To achieve the above objectives, the present invention provides the following solution: The present invention provides a static cone penetration test probe, including a probe system, an inner tube, and an outer tube for transmission connection with a rotary drilling system. The probe system is connected to the inner tube, and the probe of the probe system extends out of the outer tube at the end away from the rotary drilling system. The inner tube is connected to the outer tube through a bearing, and the outer tube rotates relative to the inner tube.

[0014] Preferably, the probe system includes the probe, a connecting rod, a connecting part, a storage medium for storing probe data, and a mobile power supply for powering the probe. The probe is connected to the connecting part via the connecting rod. The connecting part is connected to the inner tube and seals the port of the inner tube near the probe. The storage medium and the mobile power supply are both located at the end of the connecting part away from the connecting rod and are located in the inner tube.

[0015] Preferably, the end face of the connecting part near the connecting rod has a frustum-shaped structure, and the small-diameter end of the frustum-shaped structure is connected to the connecting rod.

[0016] Preferably, the end of the inner tube away from the connecting part is closed.

[0017] Preferably, both the outer tube and the inner tube are steel pipes.

[0018] The present invention also provides a static cone penetration test device using the above-mentioned static cone penetration test probe, comprising the rotary drilling system and the static cone penetration test probe, wherein the drilling end of the rotary drilling system is connected to the end of the outer tube away from the probe.

[0019] Preferably, the rotary drilling system is a drilling rig, and the drill rod of the drilling rig is connected to the end of the outer tube away from the probe via a transmission connection.

[0020] Preferably, the drilling rig is equipped with a displacement sensor for detecting and recording the drilling depth.

[0021] Preferably, the storage medium of the probe system for storing probe data is connected to the active drill rod at the main spindle of the drilling rig via the drill rod, and the active drill rod is provided with a transmitting antenna for remote data transmission.

[0022] The present invention also provides a static cone penetration method using the above-mentioned static cone penetration device, comprising the following steps: S1: Install the probe system onto the rotary drilling system; S2: Start the rotary drilling system. Through the pressurization and rotation of the rotary drilling system, the outer tube is rotary drilled and vertical static pressure is applied to the inner tube. The inner tube transmits the pressure to the probe system connected to it, thereby realizing the static penetration test. S3: Control the drilling depth of the rotary drilling system according to the required test depth.

[0023] The present invention achieves the following main technical effects compared to the prior art: With the outer casing and rotary drilling system connected in a drive system, the rotary drilling system can directly drive the outer casing for drilling operations. During drilling, the rotary drilling system applies rotary drilling power to the outer casing. Simultaneously, because the inner and outer casings are rotatably connected, the rotary drilling system can apply vertical static pressure to the inner casing, enabling simultaneous drilling and static penetration testing. During static penetration testing, the rotary drilling action of the outer casing and the rotary drilling system continuously cuts the surrounding soil, reducing the frictional force of the soil on the rotary drilling system and the outer casing. This ensures that the probe can continuously penetrate under a certain pressure, penetrating hard soil layers similar to dense sand layers, without the problem of the probe's penetration pressure being significantly affected by the increased pressure caused by the sidewall resistance of the soil layer with depth, thus limiting the static penetration depth. This enables continuous static penetration testing operations. At the same time, the probe's extended design ensures that the probe is not disturbed by the drilling of the outer casing during static penetration testing, guaranteeing the authenticity of the test results.

[0024] Other solutions of the present invention achieve the following technical effects compared with the prior art: Displacement sensors can be used to obtain the drilling depth of the drilling rig, thereby accurately obtaining the penetration depth of the probe.

[0025] Taking advantage of the fact that the active drill rod at the drill spindle is located above the ground or water surface, the drill rod and the active drill rod are used as a data transmission path. With the help of a transmitting antenna and storage medium, real-time remote transmission of data is achieved, so that the test signal can be received at the terminal in real time, avoiding the loss of test data due to damage to the storage medium. Attached Figure Description

[0026] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of the static cone penetration device in an embodiment of the present invention; Figure 2 This is a schematic diagram of the probe system in an embodiment of the present invention; Figure 3 This is a schematic diagram of the rotary drilling system in an embodiment of the present invention; The components are: 1. Probe; 2. Connecting rod; 3. Outer tube; 4. Inner tube; 5. Drill rod; 6. Drilling rig; 7. Spindle; 8. Ground; 9. Connecting part; 10. Storage medium; 11. Mobile power supply; 12. Displacement sensor. Detailed Implementation

[0028] 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.

[0029] The purpose of this invention is to provide a static cone penetration probe, a static cone penetration device, and a static cone penetration method to solve the problems existing in the prior art. By utilizing the characteristics that the outer tube is driven to rotate by the rotary drilling system and the inner tube is not affected by the rotation of the outer tube, static cone penetration can be performed while drilling, enabling continuous static cone penetration operations.

[0030] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Please refer to Figures 1-3 This invention provides a static penetration test probe, including a probe system, an inner tube 4, and an outer tube 3 for transmission connection with a rotary drilling system. The inner tube 4 is rotatably mounted inside the outer tube 3 via bearings. The probe system is connected to the inner tube 4, using the inner tube 4 as the carrier of the probe system. The rotary drilling system can apply rotary drilling power to the outer tube 3 and simultaneously apply vertical static pressure to the inner tube 4, enabling static penetration testing while drilling. This is manifested as a state of relative rotation between the outer tube 3 and the inner tube 4, where the outer tube 3 rotates while the inner tube 4 remains stationary. During static penetration testing, the rotary drilling power of the outer tube 3 and the rotary drilling system continuously... Cutting the surrounding soil reduces the friction of the soil on the rotary drilling system and the outer tube 3, ensuring that the probe 1 can continuously penetrate under a certain pressure, penetrating hard soil layers similar to dense sand layers, without the problem of the penetration pressure of the probe 1 being greatly affected by the sidewall resistance of the soil layer increasing with depth, thus limiting the static penetration depth. This enables continuous static penetration operation. The probe 1 of the probe system extends out of the outer tube 3 away from the rotary drilling system, ensuring that the probe 1 is not disturbed by the drilling of the outer tube 3 during the static penetration operation, thus ensuring the authenticity of the test results.

[0032] The distance from which probe 1 extends out of outer tube 3 is 1m to 1.5m, and the distance can be determined by the user as needed.

[0033] The probe system includes a probe 1, a connecting rod 2, a connecting part 9, a storage medium 10 for storing probe data, and a mobile power supply 11 for power supply. The storage medium 10 and the probe 1 are both electrically connected to the mobile power supply 11. The storage medium 10 is also electrically connected to the probe 1 for data transmission. The probe 1 is connected to the connecting part 9 via the connecting rod 2. The connecting part 9 is connected to the inner tube 4 and seals the port of the inner tube 4 near the probe 1. The storage medium 10 and the mobile power supply 11 are both located at the end of the connecting part 9 away from the connecting rod 2 and are located in the inner tube 4. The connecting part 9 is used to seal the end of the inner tube 4 to prevent soil from entering the inner tube 4 during the downward penetration of the strata and affecting the storage medium 10 and the mobile power supply 11. Passages can be set inside the connecting rod 2 and the connecting part 9 for wiring to avoid exposed wiring.

[0034] The connecting rod 2 and the connecting part 9 can be integrally formed, and the material can be steel to improve its structural strength.

[0035] The end face of the connecting part 9 near the connecting rod 2 is a frustum-shaped structure. The small diameter end of the frustum-shaped structure is connected to the connecting rod 2. At the same time, it can be designed that the small diameter end of the frustum-shaped structure is completely covered by the end face of the connecting rod 2 to reduce penetration resistance.

[0036] The end of the inner tube 4 furthest from the connecting part 9 is sealed off, thus achieving full enclosure of the inner tube 4 and further reducing the impact of the external environment on the internal storage medium 10 and the mobile power supply 11.

[0037] Both outer pipe 3 and inner pipe 4 are steel pipes to reduce the impact of the formation on outer pipe 3 and inner pipe 4.

[0038] The present invention also provides a static cone penetration device using the above-mentioned static cone penetration probe, including a rotary drilling system and a static cone penetration probe. The drilling end of the rotary drilling system is connected to the end of the outer tube 3 away from the probe 1. The connection can be a threaded connection to transmit the rotational power to the outer tube 3.

[0039] In one embodiment, the rotary drilling system is a drill 6, and the drill rod 5 of the drill 6 is connected to the end of the outer tube 3 away from the probe 1 via a transmission connection. In other embodiments, other types of rotary drilling equipment may also be selected as the rotary drilling system.

[0040] The drilling rig 6 is equipped with a displacement sensor 12 for detecting and recording the drilling depth. The recording can be achieved by transmitting the data to a storage device. The drilling depth of the drilling rig 6 can be obtained by using the displacement sensor 12 and, in conjunction with the pre-measured length of the static cone penetration probe, the penetration depth of the probe 1 can be accurately obtained.

[0041] Since the material of the drill rod 5 itself can transmit signals, in conjunction with a signal amplifier, the storage medium 10 of the probe system used to store probe data can be electrically connected to the active drill rod at the spindle 7 of the drilling rig 6 through the drill rod 5. The active drill rod is equipped with a transmitting antenna for remote data transmission. Taking advantage of the characteristic that the active drill rod is located on the ground 8 or outside the water surface, the drill rod 5 can be used as a data transmission path. In conjunction with the signal amplifier, transmitting antenna and storage medium 10, real-time remote data transmission can be achieved, thereby receiving the test signal at the terminal in real time and avoiding the loss of test data due to damage to the storage medium 10.

[0042] The present invention also provides a static cone penetration method using the above-mentioned static cone penetration device, comprising the following steps: S1: Install the probe system onto the rotary drilling system; S2: Start the rotary drilling system located on the ground 8 or offshore platform. Through the pressurization and rotation of the rotary drilling system, the outer tube 3 is rotary drilled and vertical static pressure is applied to the inner tube 4. The outer tube 3 cuts the surrounding strata through rotary drilling. The strata debris is carried out of the borehole through mud circulation. The inner tube 4 transmits pressure to the probe system connected to it. The probe 1 of the probe system penetrates into the test stratum by bearing static pressure. The parameters of the stratum are obtained through the sensor inside the probe 1, thereby realizing the static penetration test. During the drilling process of the rotary drilling system, the penetration depth of the probe 1 is extended by continuously extending the drill rod 5. S3: Control the drilling depth of the rotary drilling system according to the required test depth, and the static penetration test can be completed within the entire depth during the drilling process; during the drilling process, the displacement data measured by the displacement sensor 12 designed on the rotary drilling system, together with the static penetration data transmitted by the transmitting antenna, are transmitted to the terminal, which can realize the automatic matching of test point depth and formation test parameters.

[0043] Any adaptive changes made according to actual needs are within the scope of protection of this invention.

[0044] It should be noted that, for those skilled in the art, it is obvious that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0045] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A static cone penetration test probe, characterized in that, It includes a probe system, an inner tube, and an outer tube for transmission connection with a rotary drilling system. The probe system is connected to the inner tube, and the probe of the probe system extends out of the outer tube at the end away from the rotary drilling system. The inner tube is connected to the outer tube by a bearing, and the outer tube rotates relative to the inner tube.

2. The static cone penetration test probe according to claim 1, characterized in that, The probe system includes the probe, a connecting rod, a connecting part, a storage medium for storing probe data, and a mobile power supply for powering the system. The probe is connected to the connecting part via the connecting rod. The connecting part is connected to the inner tube and seals the port of the inner tube near the probe. The storage medium and the mobile power supply are both located at the end of the connecting part away from the connecting rod and are located inside the inner tube.

3. The static cone penetration test probe according to claim 2, characterized in that, The end face of the connecting part near the connecting rod has a frustum-shaped structure, and the small-diameter end of the frustum-shaped structure is connected to the connecting rod.

4. The static cone penetration test probe according to claim 2, characterized in that, The end of the inner tube away from the connecting part is closed.

5. The static cone penetration test probe according to claim 1, characterized in that, Both the outer tube and the inner tube are steel pipes.

6. A static cone penetration test device, characterized in that, The static cone penetration test probe as described in any one of claims 1-5 includes the rotary drilling system and the static cone penetration test probe, wherein the drilling end of the rotary drilling system is connected to the end of the outer tube away from the probe.

7. The static cone penetrometer according to claim 6, characterized in that, The rotary drilling system is a drilling rig, and the drill rod of the drilling rig is connected to the end of the outer tube away from the probe via a transmission connection.

8. The static cone penetrometer according to claim 7, characterized in that, The drilling rig is equipped with displacement sensors for detecting and recording drilling depth.

9. The static cone penetrometer according to claim 7, characterized in that, The storage medium of the probe system for storing probe data is connected to the active drill rod at the main shaft of the drilling rig via the drill rod, and the active drill rod is equipped with a transmitting antenna for remote data transmission.

10. A static cone penetration test method, characterized in that, The application of the static cone penetrometer as described in any one of claims 6-9 includes the following steps: S1: Install the probe system onto the rotary drilling system; S2: Start the rotary drilling system. Through the pressurization and rotation of the rotary drilling system, the outer tube is rotary drilled and vertical static pressure is applied to the inner tube. The inner tube transmits the pressure to the probe system connected to it, thereby realizing the static penetration test. S3: Control the drilling depth of the rotary drilling system according to the required test depth.

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