Monitoring device for simulating horizontal vibration of single pile under Rayleigh wave

Abstract

The invention discloses a monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves. Belongs to the field of pile foundation engineering research in the civil engineering field and comprises a model box, a steel strand is arranged on the upper portion of the edge of the model box, the left side is connected with a fixed end through a buckle and is not separated from the fixed end in the experiment process, and the right side is connected with a spring dynamometer through a buckle. The right side of the spring dynamometer is connected with a left movable hinge on the test pile through a steel strand, the right movable hinge is connected through the steel strand and bypasses a pulley arranged on the edge of the upper portion of the model box, the tail end of the steel strand is connected with a weight pan, and the axis of the spring dynamometer, the horizontal center line of the movable hinge and the horizontal section of the steel strand are located on the same horizontal plane; the test pile is further connected with a displacement sensor used for monitoring experimental displacement.

Description

Technical Field

[0001] The invention belongs to the technical field of pile foundation engineering in the field of civil engineering, and relates to a monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves. Background Art

[0002] In engineering construction, the demand for pile foundation engineering is increasing, especially in the fields of bridges, high-rise buildings and ports. As an important foundation form, the stability and safety of pile foundation are of vital importance. Under the action of earthquake, the pile foundation will be affected by horizontal vibration, which puts higher requirements on the design and construction of pile foundation. Pile foundations come in various forms, including end-bearing piles and friction piles, each of which is suitable for different geological conditions and load requirements. Simulating the horizontal vibration characteristics of piles under earthquake Rayleigh waves helps to improve the seismic performance of the project.

[0003] Since there are no or few monitoring devices for the horizontal vibration of single piles under earthquake Rayleigh waves, many engineering problems cannot be well solved. Therefore, model tests are used to better reflect the bearing characteristics of piles. In the face of horizontal vibration loads, it is often found that the number of available loading devices is relatively small, which not only limits the possibility of experiments or applications, but also the structures of these loading devices are often quite complicated. Moreover, these devices are easily interfered by various external factors during operation. Summary of the invention

[0004] In view of the above problems, the first object of the present invention is to provide a single pile horizontal vibration load test device for simulating Rayleigh waves, which can ensure that the experimental operation is simple and easy to use and the availability of test data is guaranteed;

[0005] The second object of the present invention is to provide an experimental method for a monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves.

[0006] The technical scheme of the present invention is: a single pile horizontal vibration load test device for simulating Rayleigh waves described in the present invention comprises a model box, a steel strand is arranged around the upper part of the edge of the model box, the left side is connected to a fixed end through a ring buckle and it is ensured that the fixed end does not separate during the experiment process, the right side is connected to a spring dynamometer through the ring buckle, and then the left side of the test pile is connected to the active hinge on the right side of the spring dynamometer by the steel strand, and the right side of the active hinge is connected by the steel strand to bypass the pulley arranged at the upper edge position of the model box, the end of the steel strand is connected to a weight plate, the axis of the spring dynamometer, the horizontal center line of the active hinge and the horizontal section of the steel strand are on the same horizontal plane, and the test pile is also connected to a displacement sensor for experimental displacement monitoring.

[0007] Furthermore, the diameter of the steel strands used in the experiments was uniform.

[0008] Furthermore, the movable hinge has a ring with an open side, and the open side has a pair of handles, and the pair of handles are connected by bolts so that the ring can be sleeved and fixed on the test pile; the other side of the ring is provided with a buckle for connecting the steel strand.

[0009] Furthermore, the bolts and the buckles are connected to both sides of the spring respectively, and the displacement sensor on the test pile should be on the same horizontal line as the steel strand.

[0010] Furthermore, the axis of the spring dynamometer, the horizontal center line of the movable hinge, the pulley and the horizontal section of the steel strand are on the same horizontal plane to ensure the correctness of the experiment.

[0011] Furthermore, the test soil sample is filled in the model box to reach the position of the lower end of the set test pile.

[0012] Further, the test piles are placed in the buried test soil samples, and then the test soil samples are continuously filled in the model box.

[0013] Furthermore, the operating method of the single pile horizontal vibration load test device for simulating Rayleigh waves described in the present invention includes: filling the test soil sample in the model box to a specified height, and setting the model pile in the test soil sample by burying or pressing; installing a spring dynamometer, a movable hinge, a displacement sensor and a steel strand to ensure that the axis of the spring dynamometer, the horizontal center line of the movable hinge and the horizontal section of the steel strand are on the same horizontal plane; starting horizontal loading, adding weights to the weight plate during the process, and the total weight of the weights added in the weight plate does not exceed the difference between the maximum load allowed to be applied by the spring dynamometer and the maximum force load of the test pile.

[0014] Furthermore, the weights are added in stages, including: dividing the total weight of the weights to be added into several equal parts, and slowly placing one weight at a time; continuing to add the remaining weights in stages until the weights are added; the total weight of the weights should not be greater than the maximum load allowed by the spring dynamometer.

[0015] Furthermore, the stepwise addition of weights must be completed before the first unloading of the horizontal loading test.

[0016] The beneficial effects of the present invention are as follows: the experiment simulates the horizontal vibration load test of a single pile under Rayleigh waves, and the accuracy and reliability of the horizontal displacement test data results can be effectively improved by using a displacement sensor, thereby improving the availability of the test data; by simulating Rayleigh waves, the propagation mechanism of seismic waves in different media can be better understood, which is crucial for seismic exploration and underground structure analysis; the simulation of Rayleigh waves is very useful for studying the characteristics under complex medium conditions, and under the complex interaction conditions between the foundation and the pile foundation, the dynamic response of the pile foundation can be predicted by simulating Rayleigh waves, thereby providing theoretical guidance for engineering applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0018] In the figure, 1 is the fixed end, 2 is the test pile, 3 is the movable hinge, 4 is the spring dynamometer, 5 is the steel strand, 6 is the pulley, 7 is the weight, 8 is the weight plate, 9 is the model box, 10 is the test soil sample, and 11 is the displacement sensor. DETAILED DESCRIPTION

[0019] The specific technical scheme of the present invention is further described in detail below with reference to specific examples.

[0020] As shown in the figure, the single pile horizontal vibration load test device for simulating Rayleigh waves of the present invention comprises a fixed end 1, a test pile 2, a movable hinge 3, a spring dynamometer 4, a steel strand 5, a pulley 6, a weight 7, a weight plate 8, a model box 9, a test soil sample 10, and a displacement sensor 11;

[0021] A steel strand 5 is provided around the upper edge of the model box 9, the left side is connected to the fixed end 1 by a ring buckle to ensure that the fixed end 1 is not separated during the experiment, the right side is connected to a spring dynamometer 4 by the ring buckle, and then the left side of the spring dynamometer 4 is connected to the left side of the test pile 2 by the steel strand 5, and the right side of the movable hinge 3 is connected by the steel strand 5 to bypass the pulley 6 set at the upper edge of the model box 9, the end of the steel strand 5 is connected to a weight plate 8, the axis of the spring dynamometer 4, the horizontal center line of the movable hinge 3 and the horizontal section of the steel strand 5 are on the same horizontal plane, and the test pile 2 is also connected to a displacement sensor 11 for experimental displacement monitoring.

[0022] Furthermore, the diameters of the steel strands 5 used in the experiment are uniform.

[0023] Furthermore, the movable hinge 3 has a ring with an opening on one side, and the open side has a pair of handles, and the pair of handles are connected by bolts so that the ring can be sleeved and fixed on the test pile 2; the other side of the ring is provided with a buckle for connecting the steel strand 5.

[0024] Furthermore, bolts and ring buckles are connected to both sides of the spring respectively, and the displacement sensor 11 on the test pile 2 should be on the same horizontal line as the steel strand 5.

[0025] Furthermore, the axis of the spring dynamometer 4, the horizontal center line of the movable hinge 3, the pulley 6 and the horizontal section of the steel strand 5 are on the same horizontal plane to ensure the correctness of the experiment.

[0026] Furthermore, the model box 9 is filled with a test soil sample 10 to reach the position of the lower end of the set test pile 2.

[0027] Furthermore, the test pile 2 is placed in the buried test soil sample 10 , and then the test soil sample 10 is continuously filled in the model box 9 .

[0028] The operating method of the present invention is as follows:

[0029] 1. Determine the size of the test pile 2, the size of the model box 9, the diameter of the steel strand 5 and the mass of the weight 7 according to the designed model test;

[0030] 2. Place the test pile 2 in the test soil sample 10 in the model box 9 by embedding or pressing, and then continue to fill the test soil sample 10 to a suitable position;

[0031] 3. Then place the displacement sensor 11 at a suitable position of the test pile 2;

[0032] 4. Ensure that the axis of the spring dynamometer 4, the horizontal center line of the movable hinge 3 and the horizontal section of the steel strand 5 are on the same horizontal plane, connect them in sequence through the steel strand 5, and connect the weight plate 8 at the end through the pulley 6;

[0033] 5. Then add weight 7 to weight plate 8;

[0034] 6. Then, determine the total weight of the weights 7 to be added according to the specific test, and divide the total weight of the weights 7 to be added into several equal parts; slowly place the weights 7 at the beginning, observe the displacement of the displacement sensor 11 on the test pile 2, and then continue to add the remaining weights 7 in stages until the weights 7 are added. The staged addition of weights 7 must be completed before the first unloading of the horizontal loading test;

[0035] 7. Finally, the experimental data is obtained through the displacement sensor 11 and the spring dynamometer 4 and processed.

Claims

1. A monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves, characterized in that: The invention comprises a model box (9), a test pile (2) is arranged inside the model box (9), and a movable hinge (3) is arranged on the middle upper end of the test pile (2).

2. A monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to claim 1, characterized in that: The movable hinge (3) has a collar with an open side, and the open side has a pair of handles, the collar is sleeved and fixed on the test pile (2) by bolt connection, and a buckle is provided on the other side of the collar.

3. A monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to claim 1, characterized in that: A steel strand (5) is installed around the upper edge of the mold box (9). A fixed end (1) is connected to the leftmost side of the steel strand (5) via a buckle, and a spring dynamometer (4) is connected to the right side of the steel strand (5) via a buckle.

4. A monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to claim 3, characterized in that: A pulley (6) is arranged near the upper edge of the near-mold box (9).

5. A monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to claim 4, characterized in that: The right side of the spring dynamometer (4) is connected to the movable hinge (3) through a steel strand (5) and then passes around a pulley (6) arranged at the upper edge of the model box (9). A weight plate (8) is connected to the end of the steel strand that passes around the pulley (6), and a weight (7) is placed on the weight plate (8).

6. A monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to claim 2, characterized in that: A displacement sensor (11) is also connected to the test pile (2); The displacement sensor (11) and the steel strand (5) are on the same horizontal line.

7. The monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to claim 1, characterized in that: A test soil sample (10) is placed inside the model box (9). The test soil sample (10) reaches the position of the lower end of the set test pile (2).

8. The monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to claim 5, characterized in that: The axis of the spring dynamometer (4), the horizontal center line of the movable hinge (3), the pulley (6) and the horizontal section of the steel strand (5) are on the same horizontal plane.

9. The monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to claim 3, characterized in that: The diameters of the steel strands (5) used are consistent.

10. The operating method of the monitoring device for simulating horizontal vibration of a single pile under Rayleigh waves according to any one of claims 1 to 9, characterized in that: The operation method is as follows: Step (1): Determine the size of the test pile (2), the size of the model box (9), the diameter of the steel strand (5) and the mass of the weight (7) according to the designed model test; Step (2): placing the test pile (2) in the test soil sample (10) in the model box (9) by embedding or pressing, and then continuing to fill the test soil sample (10) to the required position; Step (3): installing the displacement sensor (11) at a position corresponding to the test pile (2); Step (4): ensure that the axis of the spring dynamometer (4), the horizontal center line of the movable hinge (3) and the horizontal section of the steel strand (5) are on the same horizontal plane, connect them in sequence through the steel strand (5), and then connect the weight plate (8) at the end through the pulley (6); Step (5): Then add the weight (7) into the weight plate (8); Step (6): Then, the total weight of the weights (7) to be added is determined according to the specific test, and the total weight of the weights (7) to be added is divided into several equal parts; the weights (7) are placed, and the displacement of the displacement sensor (11) on the test pile (2) is observed, and then the remaining weights (7) are added in stages until the weights (7) are added. The staged addition of the weights (7) must be completed before the first unloading of the load in the horizontal loading test; Step (7): Finally, experimental data is obtained through the displacement sensor (11) and the spring dynamometer (4) and the experimental data is processed.

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