Simulation test method and simulation test device for underwater pile foundation reinforcement

Abstract

The invention discloses a simulation test method for underwater pile foundation reinforcement and a simulation test device thereof.The simulation test method comprises the steps that a simulation pile foundation is manufactured, and the simulation pile foundation has corresponding defects and is used for simulating a to-be-reinforced target pile foundation; the simulation pile foundation is tested, and the test result of the simulation pile foundation is approximately used as the performance of the target pile foundation; one or more pile foundation reinforcing methods are adopted to reinforce the simulation pile foundation, the reinforced simulation pile foundation is tested, and the actual effect of the target pile foundation after reinforcement is simulated through test results; and selecting a corresponding reinforcing method according to a test result. According to the defect condition of the pile foundation, the defect pile foundation and the corresponding environment condition are restored in the laboratory, the reinforcing condition of the target pile foundation is approximately restored from the laboratory through the simulation pile foundation, and targeted guidance is provided for reinforcing and selection of the actual pile foundation.

Description

Technical Field

[0001] The invention relates to a simulation test method for underwater pile foundation reinforcement and a simulation test device thereof. Background Art

[0002] In the field of engineering construction, underwater pile foundations differ from terrestrial pile foundations. Due to the constant erosion and corrosion of water flow, underwater pile foundations may develop defects during construction. Over long-term use, they are more prone to corrosion, shrinkage, exposed reinforcement, and other defects in areas affected by water flow. Pile foundation defects can reduce the foundation's bearing capacity, making it impossible to meet the project's design requirements and, in severe cases, causing accidents. Therefore, measures must be taken to strengthen defective pile foundations. For defective pile foundations, the specific impact of the defects on their various performance properties is crucial. After implementing specific reinforcement measures, it is crucial to determine whether the reinforced pile foundation meets the requirements. In actual projects, the location and type of pile foundation defects vary significantly. Underwater pile foundation reinforcement projects require consideration of which repair methods can be used depending on the location and type of defect, and which repair method is most effective or most suitable for the current pile foundation. Summary of the Invention

[0003] In view of the above shortcomings, the object of the present invention is to provide a simulation test method and simulation test device for underwater pile foundation reinforcement.

[0004] To this end, the present invention provides a simulation test method for underwater pile foundation reinforcement, including making a simulated pile foundation, the simulated pile foundation having corresponding defects, and being used to simulate a target pile foundation to be reinforced; testing the simulated pile foundation, and using the test results of the simulated pile foundation as an approximation of the performance of the target pile foundation; reinforcing the simulated pile foundation using one or several pile foundation reinforcement methods, testing the reinforced simulated pile foundations respectively, and using the test results to simulate the actual effect of the target pile foundation after reinforcement; and selecting a corresponding reinforcement method based on the test results.

[0005] Furthermore, the production of the simulated pile foundation includes: prefabricating a pile foundation with a weak portion, the position of the weak portion on the prefabricated pile foundation corresponds to the position of the target pile foundation defect, placing the prefabricated pile foundation into a test device to apply a load, the force-applying mechanism gradually increases the pressure to fracture the weak portion of the pile foundation, and after chiseling and cleaning the fractured portion, a simulated pile foundation is formed.

[0006] Furthermore, when the pile foundation is prefabricated, an air pipe is buried at the corresponding weak position. The air pipe can be fixed to the vertical reinforcement of the steel cage or to the short reinforcement. Gas is introduced before the concrete begins to set. After the concrete hardens, a cavity is generated at the corresponding position to form a weak position.

[0007] Furthermore, a rubber bag is fixed at the end of the air pipe, and cracks are provided on the surface of the rubber bag. When high-pressure gas is introduced, the rubber bag expands, the cracks become larger, and the gas enters the concrete. After the injection of gas is stopped, the rubber bag contracts, preventing the concrete from entering the air pipe. When chiseling and cleaning the fracturing area, the air pipe is exposed. After removing the rubber bag, the air pipe is used as a grouting pipe for grouting and reinforcement of the corresponding area.

[0008] An air injection mechanism and a vibrating mechanism can also be used. The air injection mechanism includes an air injection pipe. The air injection pipe and the vibrating mechanism are inserted when pouring concrete. After the vibrating mechanism vibrates from the corresponding position, the air injection pipe and the vibrating mechanism inject gas to the corresponding position at a predetermined distance. After the concrete is formed, a cavity is generated at the corresponding position to form a weak part.

[0009] Precast concrete blocks having shapes corresponding to defect locations are prefabricated. The precast concrete blocks are weakened structures. The precast concrete blocks are formed on the vertical bars of the steel cage or fixed on the vertical bars after forming, and then concrete is poured a second time to form a precast pile foundation with a weak location.

[0010] Furthermore, the precast concrete blocks are formed into weakened structures by using cement with a lower grade than the pile foundation concrete, injecting gas or burying cracks therein. After the precast concrete blocks are precast, a force-applying mechanism is used to apply a predetermined pressure to the precast concrete blocks to fracture the internal structure of the precast concrete, and then the fractured precast concrete blocks are fixed to the steel cage.

[0011] Furthermore, it also includes a box body, in which soil samples are filled. The soil samples are made to correspond to the soil in the area where the target pile foundation is located. The pile foundation is reinforced in the box body or pressed into the soil sample after reinforcement. The box body and the pile foundation are placed in a test device as a whole for testing.

[0012] The present invention also discloses a simulation test device for the above-mentioned simulation test method of underwater pile foundation reinforcement, the simulation test device includes a base, support columns fixed on the base and distributed in a mirror image, a cavity is arranged above the base, the cavity can accommodate the box, a positioning plate is provided above the box, a positioning hole is provided in the middle of the positioning plate, the pile foundation passes through the positioning hole, a force-applying mechanism is provided above the box, the force-applying mechanism is fixed on a cross-arranged beam, and the beam is connected to the support column.

[0013] The beneficial technical effects of the present invention are:

[0014] A simulation test method for underwater pile foundation reinforcement of the present invention is applied to the reinforcement of underwater pile foundations. Specifically, when defects in the underwater pile foundation need to be reinforced, the environment, geology, and the location and type of the defects of the pile foundation to be reinforced are investigated and collected. According to the defects of the pile foundation, the defective pile foundation and the corresponding environmental conditions are restored in the laboratory. The simulated pile foundation simulating the actual defects of the target pile foundation is reinforced (the reinforcement condition of the simulated target pile foundation is simulated). Multiple simulated pile foundations can be made, and one or more reinforcement methods are selected according to the analysis. The simulated pile foundations are reinforced respectively. Then, various performances of the reinforced pile foundation are determined through experiments, thereby approximately restoring the reinforcement condition of the target pile foundation in the laboratory, and providing targeted guidance for the reinforcement and selection of the actual pile foundation. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 is a schematic diagram of a specific embodiment of a test device;

[0016] Figure 2 Schematic diagram of a specific embodiment 1 for simulating pile foundation production;

[0017] Figure 3 Schematic diagram of Example 2 for simulating pile foundation production;

[0018] Figure 4 Schematic diagram of Example 3 for simulating pile foundation production;

[0019] Figure 5 Schematic diagram of the test on the reinforced simulated pile foundation.

[0020] Explanation of the accompanying reference numerals: 1. Simulated pile foundation; 2. Defect location; 3. Air pipe; 4. Rubber bag; 5. Vertical reinforcement; 6. Formwork; 7. Precast concrete block; 8. Vibrating mechanism; 9. Simulation test device; 901. Base; 902. Support column; 903. Box; 904. Force-applying mechanism; 905. Beam. DETAILED DESCRIPTION

[0021] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0022] Reference Figures 1 to 5As shown, a simulation test method for underwater pile foundation reinforcement of the present invention includes preparing a simulated pile foundation 1, the simulated pile foundation 1 having corresponding defects, for simulating a target pile foundation to be reinforced; testing the simulated pile foundation 1, and using the test results of the simulated pile foundation 1 as an approximation of the performance of the target pile foundation; reinforcing the simulated pile foundation 1 using one or more pile foundation reinforcement methods, and testing the reinforced simulated pile foundation 1 separately, using the test results to simulate the actual performance of the target pile foundation after reinforcement; and selecting a corresponding reinforcement method based on the test results. Underwater pile foundations are subject to water scouring. In actual engineering, the environment varies greatly, such as the location and duration of water scouring, which can lead to significant differences in the location, degree, and type of damage to different pile foundations. These differences have a significant impact on the pile foundation and the reinforcement methods and techniques. Pile foundation reinforcement often relies on empirical judgment. For example, if the damage is severe, such as exposed rebar, rebar planting is required, and if cracks occur, grouting and other methods can be used for reinforcement or repair. Similarly, the present invention also needs to observe and analyze the damaged parts of the actual pile foundation, as well as the water flow conditions and geological conditions, collect its damage information and data, and then, based on the determined defect conditions, produce a simulated pile foundation 1 with similar defects, and use the simulated pile foundation 1 to approximately replace the actual pile foundation for testing, and approximately obtain the performance of the damaged pile foundation. Based on the results of the simulation test, appropriate reinforcement methods and techniques can be selected. After the simulated pile foundation 1 is reinforced, the simulated pile foundation 1 can be tested again, such as a static load test, to test the performance of the reinforced pile foundation. Based on the results, the corresponding reinforcement method can be selected to reinforce the actual damaged target pile foundation.

[0023] In the above embodiment, referring to Figures 2 to 4 As shown, the production of the simulated pile foundation 1 includes: prefabricating a pile foundation with a weak part, the position of the weak part on the prefabricated pile foundation corresponds to the target pile foundation defect position 2, placing the prefabricated pile foundation in the test device and applying a load, the force-applying mechanism 904 gradually increases the pressure to fracture the weak part of the pile foundation, and after chiseling and cleaning the fractured part, the simulated pile foundation 1 is formed. Figure 2 As shown, in Example 1, when the pile foundation is prefabricated, an air pipe 3 is buried in the corresponding weak part. The air pipe 3 can be fixed on the vertical reinforcement 5 of the steel cage or fixed on the short reinforcement. The air pipe 3 passes through one end of the template 6 and can be connected to a high-pressure air pump. After the concrete is poured and vibrated, a certain amount of gas is introduced into the concrete through the air pipe 3 before the concrete initially sets. After the concrete hardens, a cavity is generated at the corresponding part to form a weak part. High-pressure gas will also split the unsolidified concrete structure. After hardening, there will be a certain amount of cracks in this part. According to the needs of the actual simulation, the air pipe port is generally facing the outside of the pile body. The position of the air pipe port is set according to the actual range of the defect position 2. For example, when the reinforcement is just exposed, the air pipe port can be tied to the vertical reinforcement 5. If the diameter is reduced, the short reinforcement can be connected to the vertical reinforcement 5. The air pipe port is set on the short reinforcement, so that a weak part corresponding to the target pile foundation can be formed. Refer to Figure 2 As shown, a rubber bag 4 is fixed at the end of the air pipe 3, and cracks are provided on the surface of the rubber bag 4. When high-pressure gas is introduced, the rubber bag 4 expands and the cracks become larger, and the gas enters the concrete. After the injection of gas is stopped, the rubber bag 4 shrinks, and the shrinkage of the cracks prevents the concrete from entering the air pipe 3. When the fracturing part is chiseled out and cleaned, the air pipe 3 is exposed. After the rubber bag 4 is removed, the air pipe 3 is used as a grouting pipe for grouting reinforcement to the corresponding part. This embodiment combines a simpler simulation reinforcement method. During the production process of the simulated pile foundation 1, the air pipe 3 is reserved for forming weak parts, and measures are taken to prevent the air pipe 3 from being blocked after the concrete hardens. During the reinforcement stage, the simulated pile foundation 1 is reinforced by grouting through the air pipe 3, which simplifies the steps. Figure 3 As shown, in specific embodiment 2, an air injection mechanism and a vibrating mechanism 8 are used. The air injection mechanism includes an air injection pipe 3. The air injection pipe 3 and the vibrating mechanism 8 are inserted during concrete pouring. After the vibrating mechanism 8 vibrates from the corresponding position, the air injection pipe 3 and the vibrating mechanism 8 are separated by a predetermined distance to inject gas into the corresponding position. After the concrete is formed, a cavity is generated at the corresponding position to form a weak point. In embodiment 2, the air injection pipe 3 and the vibrating mechanism 8 are inserted into the concrete together, but the method of vibrating first and then injecting air is adopted. After the vibrating rod completes the vibration and is a certain distance away from the weak area, the nozzle of the air injection pipe 3 injects a certain amount of gas into the weak area to prevent the subsequent vibration of the vibrating mechanism 8 from discharging the gas or unexpectedly entering other areas. After the air injection is completed, the air injection pipe 3 is pulled out, and the vibrating mechanism 8 continues to vibrate other areas. After the concrete hardens, a weak concrete structure is formed in the corresponding area.

[0024] Reference Figure 4 As shown, in the specific embodiment 3 of the present invention, the production of the simulated pile foundation 1 includes: prefabricating a prefabricated concrete block 7 having a shape corresponding to the defect position 2, the prefabricated concrete block 7 being a weakened structure, the prefabricated concrete block 7 being formed on the vertical reinforcement 5 of the steel cage or fixed on the vertical reinforcement 5 after forming, and then pouring concrete a second time to form a prefabricated pile foundation with a weak part. The prefabricated concrete block 7 can be produced by the air injection method of embodiment 1, or the prefabricated concrete block 7 can be formed into a weakened structure by using cement with a lower grade than the pile foundation concrete or by embedding cracks and impurities therein. The embedded cracks can be filled in the concrete with concrete blocks that have been pressed out of the cracks. The prefabricated concrete block is made using a template 6, so the weak area formed is more accurate compared to embodiments 1 and 2. For example, the actual defect position 2 after being washed by water has different shapes. Even after being chiseled out, its shape becomes more regular, but there are still considerable differences. A template 6 of similar shape can be used to produce a weak part of the corresponding shape. After the prefabricated concrete block 7 is made, it can also be as Figure 1The test equipment shown uses a force-applying mechanism 904 to apply a predetermined pressure to the precast concrete block 7, thereby fracturing the internal structure of the precast concrete. The degree of fracturing here is such that cracks appear on the precast concrete block 7, but the integrity of the overall structure is still maintained. The precast concrete block 7 after the fracturing treatment is then fixed on the steel cage, and concrete is poured to form a simulated pile foundation 1.

[0025] Reference Figure 1 As shown, the simulated pile foundation 1 is placed in a simulation test device 9, which includes a base 901, four mirror-image support columns 902 fixed on the base 901, a cavity is set above the base 901, the pile foundation passes through the positioning hole on the positioning plate, and a force-applying mechanism 904 is set above the positioning plate. The force-applying mechanism 904 includes a jack, a pressure plate is connected below the jack, and a bearing head is set below the pressure plate. The pile foundation is fixed to the bearing head. The force-applying mechanism 904 is fixed on a cross-arranged beam 905. A pressure sensor can be set on the force-applying mechanism 904. One end of the beam 905 is connected to a support column. The beam 905 can be fixedly connected or movably connected to a track and driven by a driving device to move the beam 905 longitudinally. After the simulated pile foundation 1 is placed in the simulation test device 9, the central axis of the pile foundation coincides with the force-applying direction of the force-applying mechanism 904. The force-applying mechanism 904 gradually increases the pressure applied until the weak position is damaged or broken, which can more realistically simulate the actual condition of the target pile foundation. The equipment and methods of other pile foundation tests can also be used to measure the pile foundation to determine its stress and bearing capacity. Select a suitable reinforcement method to reinforce the simulated pile foundation 1. In order to simulate the influence of the environment on reinforcement more realistically, a soil sample can be made. The soil sample can be sampled on site and filled into the box 903 and compacted. A certain amount of water is injected above the soil sample, and reinforcement is simulated in the box 903. Of course, if the reinforcement method of cofferdam drainage is actually adopted, it is not necessary to perform the above simulation. The reinforcement method can adopt the fiber sleeve grouting method, steel-concrete composite casing, high-pressure grouting, structural reinforcement method, etc. in the prior art. One or several reinforcement methods can be selected to reinforce the pile foundation respectively. The following describes some of the reinforcement methods selected in this embodiment. The fiber sleeve grouting method involves using underwater robots or divers to clean pile attachments, clean and remove defective concrete, assemble fiber sleeves on the water surface, sink the sleeves to the defective section, and inject underwater non-dispersible grouting material for reinforcement. This method can be used with or without water. When using water, the water flow rate needs to meet certain flow rate requirements to avoid concrete loss. Steel-concrete composite casings, prefabricated steel plate casings, are welded and assembled underwater and then filled with micro-expanding polymer concrete for repair. The high-pressure grouting method first determines and locates the defect location, and then uses high-pressure grouting to spray a special slurry into the defective location of the pile foundation to form a consolidated body for repair. The structural reinforcement method uses steel casing and ultra-high performance concrete to reinforce the defective location. Figure 5As shown, a box 903 matching the cavity of the simulation test device 9 is provided, a positioning plate is provided above the box 903, a positioning hole is provided in the middle of the positioning plate, the box 903 is filled and compacted with corresponding soil samples, and reinforced by high-pressure grouting and other reinforcement methods, the reinforced box 903 is placed together with the pile foundation in the cavity of the simulation test device 9 for testing, a displacement sensor and a strain patch can be provided on the pile foundation, the strain patch can be fixed to the pile foundation by gluing, the quality and performance of the reinforced pile foundation are tested, the sensor and the strain patch are connected to the data acquisition center through wires, in order to avoid the pile foundation being pressed into the soil sample and damaging the strain patch, the fixed points on the pile foundation are first positioned, a groove is opened at the corresponding point, the groove is cleaned, and the strain patch is fixed in the groove, the wire can be protected by a protective tube, and the protective tube is vertically fixed to the pile foundation. It should be noted that Figure 5 The diagram is only a schematic diagram and only shows the wires, not the protective tube. Figure 5 The distance between the central vertical conductor and the pile foundation is for illustrative purposes only. In reality, the conductor is located in a protective tube that is placed against the pile foundation. A variety of testing techniques are available for testing reinforced pile foundations. We can utilize existing pile foundation testing methods and equipment, such as static load testing, ultrasonic testing, high-strain testing, and acoustic transmission testing, to measure the bearing capacity, deformation characteristics, structural integrity, and cracks of the reinforced piles. By integrating these test results, we can approximately simulate the performance of different reinforcement methods on the target pile foundation and in the corresponding environment, determine whether the design objectives have been achieved, and determine and select the appropriate reinforcement method for the target pile foundation.

[0026] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A simulation test method for underwater pile foundation reinforcement, characterized by: include A simulated pile foundation is produced, wherein the simulated pile foundation has corresponding defects and is used to simulate the target pile foundation to be reinforced; the simulated pile foundation is tested, and the test results of the simulated pile foundation are used to approximate the performance of the target pile foundation; Use one or several pile foundation reinforcement methods to reinforce the simulated pile foundation, test the reinforced simulated pile foundation separately, and use the test results to simulate the actual effect of the target pile foundation after reinforcement; select the corresponding reinforcement method according to the test results.

2. The simulation test method for underwater pile foundation reinforcement according to claim 1, characterized in that: The production of a simulated pile foundation includes: prefabricating a pile foundation with a weak part, the position of the weak part on the prefabricated pile foundation corresponds to the defect position of the target pile foundation, placing the prefabricated pile foundation in a test device to apply a load, and gradually increasing the pressure of the force-applying mechanism to fracture the weak part of the pile foundation. After chiseling out and cleaning the fractured part, a simulated pile foundation is formed.

3. The simulation test method for underwater pile foundation reinforcement according to claim 2, characterized in that: When prefabricating the pile foundation, an air pipe is buried in the corresponding weak position. The air pipe can be fixed on the vertical reinforcement of the steel cage or on the short reinforcement. Gas is introduced before the initial setting of the concrete. After the concrete hardens, a cavity is generated at the corresponding position to form a weak position.

4. The simulation test method for underwater pile foundation reinforcement according to claim 3, characterized in that: A rubber bag is fixed at the end of the air pipe, and cracks are provided on the surface of the rubber bag. When high-pressure gas is introduced, the rubber bag expands, the cracks become larger, and the gas enters the concrete. After the injection of gas is stopped, the rubber bag contracts, preventing the concrete from entering the air pipe. When chiseling and cleaning the fracturing area, the air pipe is exposed. After removing the rubber bag, the air pipe is used as a grouting pipe for grouting and reinforcement of the corresponding area.

5. The simulation test method for underwater pile foundation reinforcement according to claim 2, characterized in that: An air injection mechanism and a vibrating mechanism are used. The air injection mechanism includes an air injection pipe. The air injection pipe and the vibrating mechanism are inserted when pouring concrete. After the vibrating mechanism vibrates from the corresponding position, the air injection pipe and the vibrating mechanism inject gas to the corresponding position at a predetermined distance. After the concrete is formed, a cavity is generated at the corresponding position to form a weak point.

6. The simulation test method for underwater pile foundation reinforcement according to claim 2, characterized in that: Precast concrete blocks having shapes corresponding to defect locations are prefabricated. The precast concrete blocks are weakened structures. The precast concrete blocks are formed on the vertical bars of the steel cage or fixed on the vertical bars after forming, and then concrete is poured a second time to form a precast pile foundation with a weak location.

7. The simulation test method for underwater pile foundation reinforcement according to claim 6, characterized in that: The precast concrete blocks are formed into weakened structures by using cement with a lower grade than the pile foundation concrete, injecting gas or burying cracks therein. After the precast concrete blocks are precast, a force-applying mechanism is used to apply a predetermined pressure to the precast concrete blocks to fracture the internal structure of the precast concrete, and then the fractured precast concrete blocks are fixed to the steel cage.

8. A simulation test method for underwater pile foundation reinforcement according to any one of claims 2 to 7, characterized in that: It also includes a box body, in which soil samples are filled. The soil samples are made to correspond to the soil in the area where the target pile foundation is located. The pile foundation is reinforced in the box body or pressed into the soil sample after reinforcement. The box body and the pile foundation are placed in a test device as a whole for testing.

9. A simulation test device for the simulation test method of underwater pile foundation reinforcement according to claim 8, characterized in that: The simulation test device includes a base, support columns fixed on the base and distributed in a mirror image, a cavity is set above the base, the cavity can accommodate the box, a positioning plate is set above the box, a positioning hole is set in the middle of the positioning plate, the pile foundation passes through the positioning hole, a force-applying mechanism is set above the box, the force-applying mechanism is fixed on a cross-arranged beam, and the beam is connected to the support column.

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