Water standard penetration test method and device

Abstract

The invention relates to the technical field of overwater survey, and provides an overwater standard penetration test method and device. The method comprises the following steps: determining a wave displacement predicted value of a test site for carrying out an overwater standard penetration test, and calculating a first acceleration of waves according to the wave displacement predicted value; estimating the motion state of the water platform according to the first acceleration of the wave and the motion state parameter of the water platform so as to determine a displacement predicted value of the water platform; calculating a target expansion amount of an expansion compensation mechanism in the overwater standard penetration test equipment based on the displacement predicted value and the current displacement measured value of the overwater platform; optimizing control parameters of a PID controller according to a particle swarm optimization algorithm so as to enable the difference between the current expansion and contraction amount of the expansion and contraction compensation mechanism and the target expansion and contraction amount to be minimum; and the overwater standard penetration test is carried out based on the telescopic motion of the telescopic compensation mechanism. According to the scheme, the accuracy of the overwater standard penetration test can be improved.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of water surveying, in particular to a water standard penetration test method and a water standard penetration test device. BACKGROUND

[0002] The standard penetration test refers to a standard penetration device that transmits the hammering energy of a weight to the bottom of a hole through a drill rod, and records the number of hammering times required for the penetration device to cut into the soil layer by 30 cm in depth. According to the empirical correspondence between the number of hammering times and the characteristics of the soil layer, the analysis of the soil layer can be realized.

[0003] However, when the standard penetration test is performed on water, such as in the sea, the offshore construction platform is affected by the offshore environment and is in a floating state, which makes it difficult to accurately control the depth of the standard penetration to the required 30 cm depth, thereby resulting in low accuracy of the standard penetration test.

[0004] It should be noted that the information disclosed in the above background section is only used to strengthen the understanding of the background of the present disclosure, and therefore can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0005] The purpose of the present disclosure is to provide a water standard penetration test method and a water standard penetration test device, thereby at least to some extent improving the accuracy of the water standard penetration test.

[0006] Other characteristics and advantages of the present disclosure will become apparent from the following detailed description, or will be learned by practice of the present disclosure.

[0007] According to a first aspect of the present disclosure, a water standard penetration test method is provided, comprising: determining a wave displacement prediction value of a test site where the water standard penetration test is performed, and calculating a first acceleration of the wave according to the wave displacement prediction value; According to the first acceleration of the wave and the motion state parameters of the offshore platform, a motion state estimation of the offshore platform is performed to determine a displacement prediction value of the offshore platform, the offshore platform being used to load a water standard penetration test device; Based on the displacement prediction value of the offshore platform and the current displacement measurement value of the offshore platform, a target extension amount of an extension compensation mechanism in the water standard penetration test device is calculated; The control parameter of a PID controller in the water-based standard penetration test equipment is optimized according to a particle swarm optimization algorithm, so that the difference between the current telescopic amount of the telescopic compensation mechanism and the target telescopic amount is minimized, the PID controller is used to control a servo hydraulic system to drive the telescopic compensation mechanism to perform telescopic movement, the water-based standard penetration test is performed based on the telescopic movement of the telescopic compensation mechanism, and the telescopic compensation mechanism is installed at a connecting base of the water-based standard penetration test equipment and the water-based platform.

[0008] According to a second aspect of the present disclosure, a water-based standard penetration test device is provided, comprising: a wave disturbance prediction module configured to determine a wave displacement prediction value of a test site where a water-based standard penetration test is performed, and calculate a first acceleration of the wave according to the wave displacement prediction value; a water-based platform displacement prediction module configured to perform motion state estimation on a water-based platform according to the first acceleration of the wave and motion state parameters of the water-based platform, and determine a displacement prediction value of the water-based platform according to the motion state estimation result, the water-based platform being used to load a water-based standard penetration test equipment; a target telescopic amount determination module configured to calculate a target telescopic amount of a telescopic compensation mechanism in the water-based standard penetration test equipment based on the displacement prediction value of the water-based platform and a current displacement measurement value of the water-based platform; a telescopic amount adjustment module configured to optimize the control parameter of a PID controller in the water-based standard penetration test equipment according to a particle swarm optimization algorithm, so that the difference between the current telescopic amount of the telescopic compensation mechanism and the target telescopic amount is minimized, the PID controller being used to control a servo hydraulic system to drive the telescopic compensation mechanism to perform telescopic movement; and a test module configured to perform a water-based standard penetration test based on the telescopic movement of the telescopic compensation mechanism.

[0009] According to a third aspect of the present disclosure, a computer program product containing instructions which, when executed on a computer, cause the computer to perform the steps of the water-based standard penetration test method according to the first aspect.

[0010] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided, which stores a computer program, the program being executed by a processor to implement the water-based standard penetration test method according to the first aspect of the above-mentioned embodiments.

[0011] As can be seen from the above technical solutions, the water-based standard penetration test method and the water-based standard penetration test device in the exemplary embodiments of the present disclosure have at least the following advantages and positive effects: In the technical solution provided in some embodiments of the present disclosure, the wave displacement of the water test site is predicted through a wave displacement prediction sequence, the target extension and contraction amount of the extension and contraction mechanism is predicted according to the predicted wave displacement, and the extension and contraction amount of the extension and contraction compensation mechanism is adjusted through the PID controller based on the target extension and contraction amount. Compared with the related art, on the one hand, the extension and contraction compensation mechanism is installed at the connecting base of the water platform and the standard penetration device, so that the extension and contraction movement of the extension and contraction compensation mechanism can offset the influence of the up and down floating of the water platform on the penetration depth of the water standard penetration test, improve the penetration accuracy of the penetration depth, and further improve the accuracy of the water standard penetration test; on the other hand, the extension and contraction amount of the extension and contraction compensation mechanism is predicted and adjusted through the real-time monitoring-advance prediction-dynamic compensation closed-loop control, so as to reduce the delay of the PID controller of the water standard penetration test and improve the response speed.

[0012] It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, and are not limiting to the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0013] The accompanying drawings, which are incorporated into and form part of the specification, illustrate embodiments consistent with the present disclosure and, together with the specification, serve to explain the principles of the present disclosure. Obviously, the drawings in the following description are only some embodiments of the present disclosure, and other drawings can be obtained according to these drawings without creative labor for those skilled in the art.

[0014] Figure 1 A flowchart of a water standard penetration test method in an exemplary embodiment of the present disclosure is shown.

[0015] Figure 2 A flowchart of a method for obtaining a target extension and contraction amount in an exemplary embodiment of the present disclosure is shown.

[0016] Figure 3 A flowchart of a method for obtaining a current displacement measurement value of a water platform in an exemplary embodiment of the present disclosure is shown.

[0017] Figure 4 A composition diagram of a water standard penetration test device in an exemplary embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0018] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations, however, can be implemented in many different forms and should not be construed as limited to the examples set forth herein; rather, these implementations are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example implementations to those skilled in the art. The described features, structures, or characteristics can be combined in one or more implementations. In the following description, numerous specific details are provided to give a thorough understanding of implementations of the disclosure. One skilled in the relevant art will recognize, however, that the implementations of the disclosure can be practiced without one or more of the specific details, or with other methods, components, devices, steps, etc. In other instances, well-known structures have not been described in detail so as not to obscure aspects of the disclosure.

[0019] The terms "one", "a", "an", and "the" as used herein mean "at least one" or "one or more" unless expressly specified otherwise. The term "includes" means "includes but is not limited to" and the term "including" means "including, but not limited to". The term "based on" means "based, at least in part, on" unless expressly specified otherwise.

[0020] In addition, the accompanying drawings are merely schematic and are not intended to be to scale. Like reference numerals designate like or similar parts throughout the drawings and detailed descriptions thereof will not be repeated. Some of the block diagrams in the drawings are functional entities that do not necessarily have to correspond to physically or logically independent entities. These functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different network and / or processor devices and / or microcontroller devices.

[0021] In offshore wind power engineering, the standard penetration test (SPT) is one of the core in-situ test methods for foundation investigation, mainly used to evaluate the physical and mechanical properties of seabed soil (such as density, bearing capacity, liquefaction potential, etc.), and to provide key parameters for wind power foundation design (such as single pile, jacket, caisson, etc.).

[0022] However, the offshore construction platform is affected by the offshore environment and is in a floating state up and down, so that the actual penetration depth of the standard penetration test is difficult to be accurately controlled at 30 centimeters required by the standard penetration, thereby causing errors in the measurement of the number of hammer blows of the standard penetration test, affecting the accuracy of the standard penetration test.

[0023] To solve the above problems, the present disclosure provides a water standard penetration test method, which refers toFigure 1 The method may include: Step S110: Determine the predicted wave displacement value at the test site where the standard penetration test will be conducted on water, and calculate the first acceleration of the wave based on the predicted wave displacement value. Step S120: Based on the first acceleration of the wave and the motion state parameters of the platform, the motion state of the platform is estimated to determine the predicted displacement value of the platform. The platform is used to load the standard penetration test equipment. Step S130: Based on the predicted displacement value of the water platform and the current displacement measurement value of the water platform, calculate the target expansion and contraction amount of the expansion and contraction compensation mechanism in the water standard penetration test equipment. Step S140: Optimize the control parameters of the PID controller in the waterborne standard penetration test equipment according to the particle swarm optimization algorithm so as to minimize the difference between the current extension and contraction amount of the telescopic compensation mechanism and the target extension and contraction amount. The PID controller is used to control the servo hydraulic system to drive the telescopic compensation mechanism to perform telescopic motion. Step S150: Conduct a standard penetration test on water based on the telescopic movement of the telescopic compensation mechanism; The telescopic compensation mechanism is installed at the connection base between the waterborne standard penetration test equipment and the waterborne platform.

[0024] exist Figure 1 In the technical solution provided by the illustrated embodiment, wave displacement at the test site on the water is predicted using a wave displacement prediction sequence. The target expansion / contraction amount of the telescopic mechanism is then predicted based on the predicted wave displacement. Based on this target expansion / contraction amount, the expansion / contraction amount of the telescopic compensation mechanism is adjusted using a PID controller. Compared with related technologies, on the one hand, this disclosure, by installing a telescopic compensation mechanism at the connection base between the water platform and the standard penetration test device, can offset the impact of the water platform's vertical movement on the penetration depth of the standard penetration test on the water, thereby improving the penetration depth accuracy and ultimately enhancing the accuracy of the standard penetration test on the water. On the other hand, this disclosure uses a closed-loop control system of real-time monitoring, advanced prediction, and dynamic compensation to predict and adjust the expansion / contraction amount of the telescopic compensation mechanism, thereby reducing the delay of the PID controller in the standard penetration test on the water and improving the response speed.

[0025] Next, a detailed description will be given of the specific implementation method of "step S110, determining the predicted wave displacement value of the test site for conducting the standard penetration test on water, and calculating the first acceleration of the wave based on the predicted wave displacement value".

[0026] For example, the test site for the water standard penetration test is a predetermined area in the water area, and the test site can be customized according to requirements, and the example embodiment does not make special limitations.

[0027] In an example embodiment, the first acceleration of the wave can be predicted at each wave arrival time, where the displacement of the wave refers to the displacement of the wave in the direction consistent with the standard penetration direction, that is, the vertical displacement of the wave, which can also be understood as the wave height or amplitude. Similarly, the first acceleration of the wave can be understood as the first vertical acceleration of the wave, that is, the acceleration of the wave in the direction perpendicular to the horizontal plane of the water area of the test site.

[0028] In another example embodiment, the first acceleration of the wave can also be predicted periodically, that is, the extension amount of the telescopic compensation mechanism is adjusted periodically according to the method of the present disclosure. For example, the average wave period of the test site can be measured before the water standard penetration test is performed, and the first acceleration of the wave is predicted periodically with the average wave period as the adjustment period.

[0029] In another example embodiment, the first acceleration can also be predicted once when the wave period changes for more than a preset time, such as more than 1 second, so as to continue to perform the subsequent steps to offset the water platform motion disturbance caused by the wave through the extension amount of the telescopic compensation mechanism.

[0030] For example, the method for determining the wave displacement prediction value of the test site for the water standard penetration test includes: determining a wave displacement sequence composed of wave displacements in a recent preset time, inputting the wave displacement sequence into a pre-trained wave displacement prediction model, and obtaining the wave displacement prediction value according to the output of the wave displacement prediction model.

[0031] The recent preset time can be customized according to requirements or experience, and the example embodiment does not make special limitations.

[0032] For example, a long short-term memory network (LSTM) can be used to train the wave displacement prediction model. For example, historical wave data of the test site can be collected, and the wave displacement prediction model of the test site can be trained through the historical measured wave data of the test site. The training data covers data of different wave displacements and different wave periods, thereby enhancing the generalization ability of the model. The input of the wave displacement prediction model can be a wave displacement sequence composed of wave displacements in the past N seconds (sampling interval of 10 milliseconds, a total of 500 data points), and the output is the displacement prediction value of the wave in the future M seconds. The input of the wave displacement prediction model can also be a wave displacement sequence composed of displacements of the past L waves, and the output is the displacement prediction value of the next wave.

[0033] For example, at the current time (such as the current wave arrival time or the time when the periodic cycle arrives), a wave displacement sequence composed of wave displacements in the last 5 seconds can be obtained, and the wave displacement sequence is input into the pre-trained wave displacement prediction model, and the displacement prediction value of the wave is obtained according to the output of the wave displacement prediction model.

[0034] For example, the wave displacement prediction model can be incrementally trained through an adaptive correction mechanism to improve the accuracy of the displacement prediction value of the wave. For example, the displacement prediction value of the wave can be compared with the actual measured value in real time, the absolute value of the difference between the prediction value and the actual measured value is calculated, and then the deviation rate is obtained according to the ratio between the absolute value of the difference and the actual measured value. When the deviation rate is greater than the deviation rate threshold value, such as 8%, the online learning module can be started to incrementally train the LSTM model with the latest 50 groups of data to ensure the prediction stability under complex sea conditions.

[0035] In the case that the input of the wave displacement prediction model is also a wave displacement sequence composed of the displacements of the last 5 waves, and the output is the displacement prediction value of the next wave, after obtaining the displacement prediction value of the wave, the first acceleration of the wave can be obtained according to the displacement prediction value of the wave and the wave period. For example, the first acceleration of the wave is obtained according to the second derivative of the wave period with respect to the displacement prediction value of the wave.

[0036] The period of the wave can be a predicted period. For example, the wave displacement prediction model described above can also predict the time interval of the next wave according to the wave displacement sequence and the time interval of the adjacent wave displacement in the wave displacement sequence, thereby obtaining the predicted wave period. The period of the wave can also be a preset fixed value. For example, the average wave period of the test site can be measured before the water standard penetration test is performed, and the average wave period is taken as the preset wave period.

[0037] In the case that the input of the wave displacement prediction model is a wave displacement sequence composed of wave displacements in the last N seconds, and the output is a displacement prediction value of the wave in the future M seconds, the first acceleration of the wave can be obtained by taking the second derivative of the displacement prediction value of the wave with respect to M seconds.

[0038] Next, the specific implementation of "step S120, determining the displacement prediction value of the water platform according to the first acceleration of the wave, the current displacement, velocity and second acceleration of the water platform for loading the water standard penetration test equipment" is described in detail.

[0039] For example, the water platform for loading the water standard penetration test equipment is a work platform for performing standard penetration test in water environment, such as a water floating platform, which needs to have sufficient stability and safety to ensure the accuracy and reliability of the test. The water platform can be customized according to the actual water area and needs, and the example embodiment does not specially limit this.

[0040] The displacement of the water platform can also be understood as the displacement of the water platform in the direction consistent with the standard penetration direction, i.e. the displacement of the water platform in the direction perpendicular to the horizontal plane of the water area.

[0041] For example, one embodiment of step S120 can include: constructing a Kalman filter model with the first acceleration, the displacement of the water platform, the speed and the second acceleration as the state vector; and predicting the displacement prediction value of the water platform based on the Kalman filter model.

[0042] For example, a water platform motion state estimation model is constructed based on a federal Kalman filter (FKF) algorithm, and the state vector includes the vertical displacement Z, speed v, acceleration a of the water platform and the acceleration w of the wave. The federal Kalman filter algorithm is divided into two levels of local filtering (single sensor data processing) and main filtering (global state fusion), and the state estimation value is updated every preset time, such as every 5 milliseconds. Among them, the first acceleration is the state vector of one subsystem, and the displacement, speed and second acceleration of the water platform are the state vectors of another subsystem, which are respectively subjected to local filtering, and then the filtering results of the two are fused to obtain the water platform displacement prediction value.

[0043] Next, the specific embodiment of "step S130, calculating the target extension amount of the telescopic compensation mechanism in the water standard penetration test equipment based on the displacement prediction value of the water platform and the current displacement measurement value of the water platform" is described in detail.

[0044] In an example embodiment, the telescopic compensation mechanism can be understood as a telescopic compensation cylinder. The telescopic compensation mechanism is installed at the connecting base of the water standard penetration test equipment and the water platform.

[0045] For example, the telescopic compensation mechanism in the present disclosure can be a telescopic compensation cylinder driven by servo hydraulic pressure, which is installed at the connecting base of the standard penetration test equipment and the offshore platform. The stroke of the compensation cylinder can be determined according to requirements, such as ±500 mm, which can cover the vertical displacement of the offshore platform caused by conventional waves. The response speed of the compensation cylinder can also be determined according to requirements, such as less than or equal to 10 ms. The thrust can also be determined according to requirements, such as greater than or equal to 50 kN. The compensation cylinder can offset the up and down floating of the offshore platform through telescopic movement. The cylinder body is made of marine-grade stainless steel (316L) material, and the inner wall is chrome-plated to ensure wear resistance and corrosion resistance in a high-salt environment.

[0046] For example, Figure 2 A flowchart of a method for obtaining a target telescopic amount in an example embodiment of the present disclosure is shown. Referring to Figure 2 The method can include steps S210 to S230. Among them: In step S210, a first telescopic amount is obtained according to the inverse of the current displacement measurement value of the offshore platform.

[0047] For example, the telescopic amount of the telescopic compensation mechanism is required to offset the up and down floating of the offshore platform, so the telescopic amount of the telescopic compensation mechanism is opposite to the displacement of the offshore platform.

[0048] For example, Figure 3 A flowchart of a method for determining the current displacement measurement value of the offshore platform in an example embodiment of the present disclosure is shown. Referring to Figure 3 The method can include steps S310 to S330. Among them: In step S310, a first distance between the offshore platform and the horizontal plane of the water test site is measured by a range finder installed on the offshore platform.

[0049] For example, a laser range finder can be installed on the deck of the offshore platform to measure the relative distance between the offshore platform and the horizontal plane of the water area of the test site in real time, thereby obtaining the first distance.

[0050] In step S320, the current telescopic amount of the telescopic compensation mechanism is obtained based on a telescopic displacement sensor installed on the piston rod of the telescopic compensation mechanism.

[0051] For example, a magnetostrictive displacement sensor can be integrated on the piston rod of the telescopic compensation mechanism, such as a compensation cylinder, to record the actual telescopic amount of the compensation cylinder.

[0052] In step S330, a current displacement measurement value of the water platform is determined according to a fusion result of the first distance and the current telescopic amount.

[0053] For example, the first distance and the current telescopic amount can be fused to determine an absolute vertical displacement of the water platform. For example, a sum of the first distance and the current telescopic amount is determined as the current displacement measurement value of the water platform.

[0054] Through the above steps S310 to S330, the actual displacement of the water platform can be indirectly derived through the complementary data of the two sensors without additional measurement of water surface fluctuation, which not only reduces the hardware cost but also improves the anti-interference ability of the measurement result, thereby ensuring the accuracy of the water platform displacement measurement.

[0055] In step S220, a second telescopic amount is calculated by multiplying a reciprocal of the displacement prediction value of the water platform and a preset feedforward coefficient.

[0056] For example, the preset feedforward coefficient can be self-defined according to requirements, such as any value between 0.6 and 0.8.

[0057] In step S230, a target telescopic amount of the telescopic compensation mechanism in the water standard penetration test device is obtained based on a sum of the first telescopic amount and the second telescopic amount.

[0058] For example, the target telescopic amount of the compensation cylinder can be calculated according to the measurement value Z_platform and the prediction value Z_pred of the vertical displacement of the water platform, for example, the measurement value corresponds to a real-time compensation amount: S_real=-Z_platform (the negative sign represents reverse offset), the prediction value corresponds to a feedforward compensation amount: S_feed=-Z_pred, and the target compensation amount: S_total=S_real+S_feed×K, wherein K is the above-mentioned preset feedforward coefficient.

[0059] Next, the specific implementation of "step S140, the control parameters of the PID controller in the water standard penetration test device are optimized according to the particle swarm optimization algorithm, so that the difference between the current telescopic amount of the telescopic compensation mechanism and the target telescopic amount is minimized" will be described in detail.

[0060] In an exemplary embodiment, the water standard penetration test device includes a PID controller, which is used to control the servo hydraulic system to drive the telescopic compensation mechanism to perform telescopic movement. The control parameters of the PID controller include a proportional coefficient, an integral time and a differential time.

[0061] For example, after the target extension amount is obtained, the control parameters of the PID controller can be self-tuned, so as to offset the influence of the wave on the penetration depth of the standard penetration test through the extension movement of the compensation mechanism.

[0062] For example, the particle swarm optimization algorithm can be used to optimize the control parameters of the PID controller in real time, i.e., the above-mentioned proportional coefficient, integral time and differential time. The objective function of the particle swarm optimization algorithm is to minimize the error between the current extension amount and the target extension amount of the extension compensation mechanism, such as the sum of squares of the current extension amount and the target extension amount, so as to obtain the numerical value of each control parameter of the PID controller under the condition that the sum of squares of the current extension amount and the target extension amount is minimized. The control parameters of the PID controller are adjusted based on the numerical value of the control parameters, and the PID controller is driven to control the servo hydraulic system to drive the extension compensation mechanism to move based on the adjusted control parameters.

[0063] For example, when the wave period changes more than a preset time, such as 1 second, the control parameters of the PID controller can be re-tuned once, so as to ensure the compensation accuracy in different water environments. Of course, the self-tuning of the control parameters of the PID controller can also be performed periodically as described above, which is not specially limited in this exemplary embodiment.

[0064] Next, the specific implementation of "step S150, performing the water standard penetration test based on the extension movement of the extension compensation mechanism" will be described in detail.

[0065] In an exemplary embodiment, as described above, the extension compensation mechanism is installed at the connecting base of the water standard penetration test equipment and the water platform. In this way, the position of the water standard penetration test equipment on the water platform can be adjusted through the extension movement of the extension compensation mechanism, so as to perform the standard penetration test, thereby reducing the influence of the platform displacement caused by the wave on the penetration depth and ensuring the accuracy of the penetration depth of the water standard penetration test.

[0066] In an exemplary embodiment, parallelogram guide frames are arranged on both sides of the extension compensation mechanism, and the extension compensation mechanism is connected to the water platform slide rail through linear bearings. The parallelogram guide frames are used to limit the horizontal displacement of the extension compensation mechanism.

[0067] For example, parallelogram guide frames can be arranged on both sides of the compensation cylinder, and the compensation mechanism is connected to the platform slide rail through linear bearings to limit the lateral displacement of the compensation mechanism and ensure that the standard penetration device always moves in the vertical direction. Self-lubricating bearings are used at the joints of the guide frames to reduce mechanical wear and lower the movement resistance.

[0068] In an exemplary embodiment, the method in the present disclosure can further comprise: measuring an actual penetration speed of a standard penetrator of a water standard penetration test device; and adjusting a damping coefficient of the telescopic compensation mechanism when a variation of the actual penetration speed is greater than or equal to a speed fluctuation threshold, so that the variation of the actual penetration speed is less than the speed fluctuation threshold.

[0069] For example, in the present disclosure, the accuracy of the water standard penetration test can be further improved by compensating the penetration speed. For example, a fiber bragg grating strain sensor can be installed on the sidewall of the standard penetrator, and the actual penetration speed v_penetration can be calculated by measuring the strain. When v_penetration fluctuates more than ±0.05 m / s due to wave disturbance, the damping coefficient of the compensation cylinder can be adjusted to suppress the sudden change of the penetration speed during the penetration process and ensure the stability of the penetration speed.

[0070] For example, in the present disclosure, the method can further comprise: obtaining a raw blow count measured by the water standard penetration test after the water standard penetration test is completed; calculating a deviation between the actual penetration speed and the standard penetration speed during the water standard penetration test, determining a correction coefficient according to the deviation; and determining a corrected blow count of the water standard penetration test according to the product of the correction coefficient and the raw blow count, so that data analysis of the water standard penetration test is performed based on the corrected blow count.

[0071] For example, after the water standard penetration test is completed, the raw blow count recorded can be corrected by the penetration speed to obtain a corrected blow count, and the soil quality at the test site can be analyzed based on the corrected blow count. For example, the correction method for the raw blow count can be: N_corrected = N_measured × (1 + Δv / v0), where N_measured is the raw blow count measured by the water standard penetration test, N_corrected is the corrected blow count, Δv is the deviation between the actual penetration speed and the standard penetration speed, and v0 is the standard penetration speed, which can be determined according to the standard requirements, such as 0.1 m / s.

[0072] For example, in the present disclosure, the method can further comprise: monitoring the hammering force by a piezoelectric force sensor installed on the top of the standard penetration hammer during the water standard penetration test; and adjusting the lifting height of the standard penetration hammer by the servo hydraulic system when the deviation between the hammering force and the preset standard hammering force is greater than or equal to a preset value, so that the deviation between the hammering force of the standard penetration hammer and the preset standard hammering force is less than the preset value.

[0073] For example, the hammering force can also be monitored and adjusted to ensure the stability of the penetration energy. For example, a piezoelectric force sensor is installed on the top of the standard penetration hammer to monitor the impact force in real time. When the impact force deviates from the standard value, such as ±5% of 63.5 kN, the lifting height of the standard penetration hammer is adjusted by a servo motor to ensure the stability of the hammering energy and further improve the accuracy of the water-based standard penetration test.

[0074] In an exemplary scenario, taking offshore wind power survey as an example, before the formal water-based standard penetration test, the system self-checking can be started to check the sensor communication, compensation cylinder pressure and emergency device state, and collect initial wave data for a preset time period such as 30 seconds, complete the initialization of the LSTM model and the pre-tuning of the PID parameters, adjust the standard penetration device to the initial position, and align the laser to the preset test point on the seabed. During the standard penetration test, the number of hammering is recorded once every 30 centimeters, and the related data such as compensation cylinder displacement, hammering force and platform movement are stored synchronously. When the wave period is greater than the preset period, such as greater than 10 seconds, and the wave amplitude is greater than the preset amplitude, such as 5 meters, the system automatically switches to the “low speed mode”, reduces the penetration speed by 30%, and prolongs the single hammering interval to 2s to ensure the stability of the data. After the test is completed, the original hammering number of the test measurement can be corrected according to the foregoing manner.

[0075] For example, the hardware level protection can include: the compensation cylinder oil circuit is provided with an overflow valve and an explosion-proof valve to immediately cut off the power source when the system pressure is abnormal; a shear pin is installed on the top of the standard penetration device to avoid overload damage to the drill pipe. The software level monitoring can include: when the compensation error continues to be greater than a preset threshold, such as 20 mm within 5 seconds, the sound and light alarm is started, the test is paused, the sensor communication interruption is greater than a preset time period, such as 3 seconds, the system automatically switches to the backup sensor group, the cached prediction data is used to maintain the compensation (which can last for 10s), the water-based platform inclination angle is greater than a preset angle, such as 10 degrees, the standard penetration device is recovered to the initial position in an emergency, and the compensation system is locked.

[0076] In addition, the emergency operation interface in the present disclosure is equipped with an emergency control terminal independent of the main system, which can perform “emergency stop”, “manual recovery” and other operations through physical buttons to ensure the safety of the equipment in extreme cases.

[0077] Exemplarily, in the present disclosure, various sensors synchronously collect data, for example, time synchronization (synchronization error ≤ 1 μs) of the following sensors is realized through industrial Ethernet (Profinet protocol): vertical accelerometer (sampling rate 500 Hz, range ± 20g), laser range finder (sampling rate 100 Hz), wave meter (sampling rate 10 Hz), and compensation cylinder displacement sensor (sampling rate 1000 Hz). The collected data is preprocessed through an edge computing gateway, outliers are removed (3σ criterion is adopted), and transmission is compressed.

[0078] A wave pool simulation experiment was conducted on the method in the present disclosure. In a 30 m x 20 m x 5 m wave pool, regular waves with a wave height of 0.5-3 m and a period of 3-8 s were simulated, and the standard penetration data with and without wave compensation were compared. The results show that, without wave compensation, the hammering number deviation rate can reach ± 15%-25%, and after wave compensation using the method of the present disclosure, the deviation rate is controlled within ± 3%. It can be seen that, after wave compensation using the method of the present disclosure, the error of the deviation rate of the standard penetration data is significantly reduced.

[0079] At the same time, offshore field tests were also conducted using the method in the present disclosure, and the results also show that the method of the present disclosure can effectively compensate for waves and ensure the accuracy of standard penetration test data.

[0080] Through the method of the present disclosure, a closed-loop control of “real-time monitoring-advance prediction-dynamic compensation” is realized, which can effectively offset the platform motion disturbance caused by waves, effectively improve the measurement accuracy of the standard penetration number, and provide reliable data support for offshore geotechnical layer mechanics parameter evaluation.

[0081] In addition, it should be noted that the above figures are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present disclosure, and are not for limiting purposes. It is easy to understand that the processes shown in the above figures do not indicate or limit the time sequence of these processes. In addition, it is also easy to understand that these processes can be executed synchronously or asynchronously, for example, in multiple modules.

[0082] Further, the exemplary embodiments of the present disclosure also provide a water standard penetration test device 400. Referring to Figure 4As shown, the water standard penetration test device includes the following program modules: a wave disturbance prediction module 410 configured to determine a wave displacement prediction value of a test site where the water standard penetration test is performed, and calculate a first acceleration of the wave according to the wave displacement prediction value; a water platform displacement prediction module 420 configured to perform a motion state estimation of a water platform according to the first acceleration of the wave and a motion state parameter of the water platform, and determine a displacement prediction value of the water platform according to the motion state estimation result, the water platform being used to load water standard penetration test equipment; a target extension amount determination module 430 configured to calculate a target extension amount of an extension compensation mechanism in the water standard penetration test equipment based on the displacement prediction value of the water platform and a current displacement measurement value of the water platform; an extension amount adjustment module 440 configured to optimize a control parameter of a PID controller in the water standard penetration test equipment according to a particle swarm optimization algorithm, so as to minimize a difference between a current extension amount of the extension compensation mechanism and the target extension amount, the PID controller being used to control a servo hydraulic system to drive the extension compensation mechanism to perform extension movement; and a test module 450 configured to perform the water standard penetration test based on the extension movement of the extension compensation mechanism.

[0083] In an exemplary embodiment, the calculation of the target extension amount of the extension compensation mechanism in the water standard penetration test equipment based on the displacement prediction value of the water platform and the current displacement measurement value of the water platform includes: obtaining a first extension amount according to an inverse of the current displacement measurement value of the water platform; obtaining a second extension amount according to a product of an inverse of the displacement prediction value of the water platform and a preset feedforward coefficient; and obtaining the target extension amount of the extension compensation mechanism in the water standard penetration test equipment based on a sum of the first extension amount and the second extension amount.

[0084] In an exemplary embodiment, the determination of the current displacement measurement value of the water platform includes: measuring a first distance between the water platform and a horizontal plane of the water test site by a range finder installed on the water platform; obtaining a current extension amount of the extension compensation mechanism based on an extension displacement sensor installed on a piston rod of the extension compensation mechanism; and determining the current displacement measurement value of the water platform according to a fusion result of the first distance and the current extension amount.

[0085] In an exemplary embodiment, the determination of the wave displacement prediction value of the test site where the water standard penetration test is performed includes: determining a wave displacement sequence composed of wave displacements in a preset time period, inputting the wave displacement sequence into a pre-trained wave displacement prediction model, and obtaining the wave displacement prediction value according to an output of the wave displacement prediction model.

[0086] In an exemplary embodiment, the motion state parameters include displacement, velocity and second acceleration, and the motion state estimation of the offshore platform according to the first acceleration of the wave and the motion state parameters of the offshore platform includes: taking the first acceleration, the displacement, the velocity and the second acceleration of the offshore platform as a state vector to construct a Kalman filter model; and predicting the displacement of the offshore platform based on the Kalman filter model.

[0087] In an exemplary embodiment, the device further includes a penetration speed compensation module, which can be specifically configured to: measure an actual penetration speed of a standard penetrator of a standard penetration test equipment on water; and adjust a damping coefficient of the telescopic compensation mechanism when a variation of the actual penetration speed is greater than or equal to a speed fluctuation threshold, so that the variation of the actual penetration speed is less than the speed fluctuation threshold.

[0088] In an exemplary embodiment, the device further includes a data correction module, which can be specifically configured to: obtain an original number of hammer blows measured by the standard penetration test on water after the standard penetration test on water is completed; calculate a deviation between an actual penetration speed and a standard penetration speed during the standard penetration test on water, and determine a correction coefficient according to the deviation; and determine a corrected number of hammer blows of the standard penetration test on water according to a product of the correction coefficient and the original number of hammer blows, so as to analyze data of the standard penetration test on water based on the corrected number of hammer blows.

[0089] In an exemplary embodiment, the device further includes a hammer blow force stability control module, which can be configured to: monitor a hammer blow force by a piezoelectric force sensor installed on a top of a standard penetration hammer during the standard penetration test on water; and adjust a lifting height of the standard penetration hammer by the servo hydraulic system when a deviation between the hammer blow force and a preset standard hammer blow force is greater than or equal to a preset value, so that the deviation between the hammer blow force of the standard penetration hammer and the preset standard hammer blow force is less than the preset value.

[0090] In an exemplary embodiment, parallelogram guide frames are arranged on both sides of the telescopic compensation mechanism, and the telescopic compensation mechanism is connected to a slide rail of the offshore platform through linear bearings, and the parallelogram guide frames are used to limit displacement of the telescopic compensation mechanism in a horizontal direction.

[0091] The specific details of the above device are described in detail in the method embodiment, and the undisclosed details can be referred to the embodiment content of the method part, and thus will not be described again.

[0092] It should be noted that although several modules or units of the devices for action execution are mentioned in the above detailed description, such division is not mandatory. Indeed, according to exemplary embodiments of the present disclosure, features and functionalities of two or more modules or units described above can be embodied in one module or unit. Conversely, features and functionalities of one module or unit described above can be further divided into embodied by multiple modules or units.

[0093] Furthermore, although the various steps of the methods in the present disclosure are described in a particular order in the accompanying drawings, this is not required or implied that the steps must be performed in this particular order, or that all of the steps shown must be performed to achieve the desired result. Additionally or alternatively, certain steps can be omitted, multiple steps can be combined into one step, one step can be broken down into multiple steps, etc.

[0094] Exemplary embodiments of the present disclosure also provide a computer program product. The computer program product includes a computer program which, when executed by a processor, implements the water standard penetration test method described above.

[0095] In an embodiment, the computer program product can be a tangible product containing the computer program, such as a computer readable storage medium storing the computer program. The readable storage medium can be a storage medium based on electrical, magnetic, optical, electromagnetic, infrared, etc. signals, including but not limited to: random access memory (RAM), read-only memory (ROM), magnetic tape, floppy disk, flash memory (Flash), mechanical hard disk (HDD), solid state disk (SSD), etc. Exemplarily, the computer program product can be implemented as a non-volatile storage medium storing the computer program, such as read-only memory, Nand flash memory, etc.

[0096] In an embodiment, the computer program product can be an intangible product containing the computer program. Exemplarily, the computer program product can be implemented as a virtual digital product, such as an executable file, installation package, etc. digital file storing the computer program.

[0097] The code of a computer program can be written in any form of programming language, including compiled or interpreted languages. Suitable programming languages include, for example, C, Java, C++, Python, and the like. The program code can execute entirely on the user's computing device, partly on the user's computing device, as a stand-alone software package, partly on the user's computing device and partly on a remote computing device, or entirely on the remote computing device or server. In the latter scenario, the remote computing device can be connected to the user's computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computing device, such as through the Internet using an Internet Service Provider (ISP).

[0098] The computer program can be carried or transferred by any type of carrier wave, including electronic, magnetic, optical, electromagnetic, infrared, or a combination thereof. An electronic device can convert the carrier wave carrying the computer program into a digital signal, and then run the computer program. When the computer program is run on the electronic device, the code of the computer program causes the electronic device to perform (more specifically, can cause the processor of the electronic device to perform) the method steps of various example embodiments of the present disclosure, such as the method of the above-described standard penetration test method on water.

[0099] Those skilled in the art will appreciate that the various aspects of the present disclosure can be embodied as a complete hardware implementation, a complete software implementation (including firmware, microcode, etc.), or an implementation that combines hardware and software aspects, such as can be referred to as a "circuit," "module," or "system."

[0100] It should be understood that the present disclosure is not limited to the particular methods steps or structures described hereinabove and illustrated in the drawings, which can be varied in many ways. Those skilled in the art will readily recognize other implementations that are encompassed by the present disclosure, based on the specific implementations provided herein. Therefore, the specific implementations provided herein are merely exemplary, and the scope and spirit of the present disclosure are indicated by the claims, and should encompass any variations, uses, or adaptations of the present disclosure that follow, without departing from the general principles of the present disclosure, and including any variations, uses, or adaptations of the present disclosure that are known or reasonably inferable to those skilled in the art.​​​​​​

Claims

1. A method for a standard penetration test on water, characterized in that, include: Determine the predicted wave displacement at the test site where the standard penetration test will be conducted on water, and calculate the first acceleration of the wave based on the predicted wave displacement. The motion state of the platform is estimated based on the first acceleration of the wave and the motion state parameters of the platform to determine the predicted displacement value of the platform. The platform is used to load the standard penetration test equipment. Based on the predicted displacement value of the water platform and the current measured displacement value of the water platform, the target expansion and contraction amount of the expansion compensation mechanism in the water standard penetration test equipment is calculated. The control parameters of the PID controller in the waterborne standard penetration test equipment are optimized according to the particle swarm optimization algorithm so as to minimize the difference between the current extension and contraction of the telescopic compensation mechanism and the target extension and contraction. The PID controller is used to control the servo hydraulic system to drive the telescopic compensation mechanism to perform telescopic motion. A standard penetration test on water was conducted based on the telescopic movement of the aforementioned telescopic compensation mechanism. The telescopic compensation mechanism is installed at the connection base between the waterborne standard penetration test equipment and the waterborne platform.

2. The method according to claim 1, characterized in that, The calculation of the target expansion and contraction amount of the expansion and contraction compensation mechanism in the standard penetration test equipment for waterborne applications, based on the predicted displacement value of the waterborne platform and the current measured displacement value of the waterborne platform, includes: The first expansion / contraction amount is obtained based on the negative of the current displacement measurement value of the water platform; The second expansion / contraction amount is obtained by multiplying the inverse of the predicted displacement value of the water platform with a preset feedforward coefficient. Based on the sum of the first and second expansion amounts, the target expansion amount of the expansion compensation mechanism in the standard penetration test equipment for water is obtained.

3. The method according to claim 1, characterized in that, The method for determining the current displacement measurement value of the water platform includes: The first distance between the water platform and the test site is measured using a rangefinder installed on the water platform. The current extension / retraction amount of the telescopic compensation mechanism is obtained based on the telescopic displacement sensor installed on the piston rod of the telescopic compensation mechanism; Based on the fusion result of the first distance and the current expansion / contraction, the current displacement measurement value of the water platform is determined.

4. The method according to claim 1, characterized in that, The predicted wave displacement values ​​for determining the test site for the standard penetration test at sea include: A wave displacement sequence consisting of wave displacements within the most recent preset time period is determined, and the wave displacement sequence is input into a pre-trained wave displacement prediction model. The predicted wave displacement value is obtained based on the output of the wave displacement prediction model.

5. The method according to claim 1, characterized in that, The motion state parameters include displacement, velocity, and second acceleration. The step of estimating the motion state of the platform based on the first acceleration of the wave and the motion state parameters of the platform to determine the predicted displacement value of the platform includes: A Kalman filter model is constructed using the first acceleration, the displacement, velocity, and second acceleration of the water platform as state vectors. The displacement prediction value of the water platform is predicted based on the Kalman filter model.

6. The method according to claim 1, characterized in that, The method further includes: To measure the actual penetration velocity of the standard penetrator in a standard penetration test setup for waterborne standard penetration testing; When the change in the actual penetration speed is greater than or equal to the speed fluctuation threshold, the damping coefficient of the telescopic compensation mechanism is adjusted so that the change in the actual penetration speed is less than the speed fluctuation threshold.

7. The method according to claim 6, characterized in that, The method further includes: After the standard penetration test is completed, the original number of blows measured in the standard penetration test is obtained. Calculate the deviation between the actual penetration velocity and the standard penetration velocity during the standard penetration test on water, and determine the correction factor based on the deviation; The corrected number of blows for the standard penetration test in water is determined by multiplying the correction factor and the original number of blows, so as to conduct data analysis of the standard penetration test in water based on the corrected number of blows.

8. The method according to claim 1, characterized in that, The method further includes: During the standard penetration test on water, the hammering force is monitored by a piezoelectric force sensor installed on the top of the standard penetration hammer. When the deviation between the hammering force and the preset standard hammering force is greater than or equal to a preset value, the lifting height of the standard penetration hammer is adjusted by the servo hydraulic system so that the deviation between the hammering force of the standard penetration hammer and the preset standard hammering force is less than the preset value.

9. The method according to claim 1, characterized in that, The telescopic compensation mechanism is equipped with parallelogram guide frames on both sides and is connected to the slide rail of the water platform through linear bearings. The parallelogram guide frames are used to limit the horizontal displacement of the telescopic compensation mechanism.

10. A standard penetration test apparatus for water, characterized in that, include: The wave disturbance prediction module is configured to determine the predicted wave displacement at the test site where a standard penetration test is to be conducted on water, and to calculate the first acceleration of the wave based on the predicted wave displacement. The floating platform displacement prediction module estimates the motion state of the floating platform based on the first acceleration of the wave and the motion state parameters of the floating platform, and determines the displacement prediction value of the floating platform based on the motion state estimation result. The floating platform is used to load the floating standard penetration test equipment. The target expansion / contraction determination module is configured to calculate the target expansion / contraction of the expansion / contraction compensation mechanism in the standard penetration test equipment based on the predicted displacement value of the platform and the current displacement measurement value of the platform. The telescoping adjustment module is configured to optimize the control parameters of the PID controller in the waterborne standard penetration test equipment according to the particle swarm optimization algorithm, so as to minimize the difference between the current telescoping amount and the target telescoping amount of the telescoping compensation mechanism. The PID controller is used to control the servo hydraulic system to drive the telescoping compensation mechanism to perform telescoping motion. The test module is configured to conduct a standard penetration test on water based on the telescopic movement of the telescopic compensation mechanism.

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