CN103868669B - Underwater multipoint excitation pseudo-dynamic testing system - Google Patents

Abstract

The invention discloses an underwater multipoint excitation pseudo-dynamic testing system. The system is characterized in that the system is provided with a transparent water tank, the water tank is supported by a support and filled with water, and a bottom plate of the water tank is of a plane structure; a submerged floating tunnel model floating in the water is arranged in the water tank; a plurality of excitation mechanisms are horizontally arranged below the submerged floating tunnel model and are connected with the submerged floating tunnel model through anchor cables; the excitation mechanisms are longitudinally arranged at intervals and are connected with excitation points of the submerged floating tunnel model through the anchor cables in a one-to-one correspondence mode to form a multipoint excitation mechanism; the system is further provided with a driving mechanism which is used for driving the excitation mechanisms to carry out straight reciprocating motion in the transverse direction, the longitudinal direction and the vertical direction, wherein the longitudinal direction is parallel to the axis of the submerged floating tunnel model. The system can meet requirements for sizes of large-sized structural models, represent seismic oscillation and structural responses and provide a powerful means for studying underwater fine-structure seismic response mechanisms and aseismic design.

Description

An underwater multi-point excitation pseudodynamic test system

technical field

The invention relates to a pseudo-dynamic test system, more specifically to a test system for simulating the structural dynamic response of a slender structure underwater under the action of an earthquake.

Background technique

In recent years, the exploitation of marine resources has become increasingly frequent, the number of submarine oil and gas pipelines has increased at an alarming rate, and the construction of submarine oil and gas pipelines has flourished. At the same time, people have also extended the use of the ocean to the transportation field, and the research on floating tunnels in water has begun to enter people's field of vision.

Compared with other means of transportation across rivers, lakes and seas, floating tunnels in the water have unique advantages, such as not affecting waterway shipping during operation; protecting the natural scenery of the original water area; not being affected by bad weather, ensuring normal traffic all-weather wait. However, the frequent earthquakes in the open sea, especially the frequent occurrence of earthquakes and tsunamis around the world in recent years, have brought great disasters to human beings, and gradually aroused people's attention and research on marine seismic dynamics. Crustal changes caused by offshore earthquakes are potentially very dangerous for pipelines buried below the seabed or exposed on the surface of the seabed. Therefore, it is of great significance to study the dynamic response of underwater slender structures under earthquake for marine engineering construction.

Due to the complexity of the earthquake mechanism and the seismic performance of structures and the limitations of the theory, theoretical analysis alone cannot fully reveal the response process and failure mechanism of structures under earthquakes, especially for large and complex structures that exceed the specifications for seismic design. For structures and new structural systems, anti-seismic experimental research must be carried out before implementation. At present, the development of simulated seismic test equipment on land at home and abroad is relatively mature. The existing simulated seismic platform, simulated seismic room, etc., adopt a consistent excitation method for multi-point seismic input, and realize horizontal sieve movement and vertical lift on the mechanical structure. And vibration, to simulate the seismic shear wave, longitudinal wave and vibration effect, the cost is as high as tens of millions. The dynamic response of underwater slender structures under earthquake action is usually studied using theoretical methods. Although there are very few colleges and universities that have built underwater shaking tables, they can only achieve synchronous and consistent seismic input, and cannot achieve multi-point Multi-dimensional seismic input, at the same time, due to the limitation of table geometry and excitation function, can only conduct scaled short model structure experiments, and the cost is expensive.

The slender structure in water has a large span, and the distance between anchor points is relatively large, and the seismic input presents the characteristics of multi-point and multi-dimensional. Considering the spatial effect of multi-point seismic input, the seismic waves at different anchor cables show phase differences, and the span of the slender structure is relatively large, so the shaking table experiment simulation is very difficult. At present, there is no test equipment that can realize this function in China.

Contents of the invention

The present invention provides an underwater multi-point excitation pseudo-dynamic test system in order to avoid the shortcomings of the above-mentioned prior art, which can not only meet the size requirements of large-scale structural models, but also reproduce earthquake vibrations and structural responses. It provides a powerful means to study the seismic response mechanism and seismic design of underwater slender structures.

The present invention adopts following technical scheme for solving technical problems:

The structural characteristics of the underwater multi-point excitation pseudodynamic test system of the present invention are: a transparent water tank containing a water body supported by a support is provided, and the bottom plate of the water tank is a plane structure; a water suspension tunnel model suspended in the water body is arranged in the water tank; An excitation mechanism is arranged horizontally below the floating tunnel model in water, and an anchor cable is used to connect the excitation mechanism and the floating tunnel model in water; multiple groups of excitation mechanisms are arranged at longitudinal intervals, and anchor cables are placed on each group of excitation mechanisms and the floating tunnel model in water Each excitation point is connected in one-to-one correspondence to form a multi-point excitation mechanism; a drive mechanism is provided to drive the linear reciprocating motion of the excitation mechanism in the horizontal, vertical and vertical directions; The direction parallel to the axis of the floating tunnel model in water.

The structural characteristics of the underwater multi-point excitation pseudodynamic test system of the present invention also lie in:

The excitation mechanism is a three-layer excitation plate, which is the lower excitation plate supported by springs at the bottom, the middle excitation plate supported on the top surface of the lower excitation plate by the longitudinal slide rail and longitudinal slider arranged in cooperation, and the The horizontal slide rail and the horizontal slider are supported on the upper excitation plate on the top surface of the middle excitation plate; the anchor cables are positioned and connected to the upper excitation plate; the drive mechanism is independently provided with each actuator corresponding to the three-layer excitation plate, It is a transverse actuator used to drive the horizontal linear reciprocating motion of the upper excitation plate, a longitudinal actuator used to drive the longitudinal linear reciprocating motion of the middle excitation plate, and a vertical actuator used to drive the vertical reciprocating motion of the lower excitation plate .

A window is opened on the bottom plate of the water tank, and the upper excitation plate is placed in the window of the bottom plate of the water tank, and the periphery of the upper excitation plate and the periphery of the window are closed and connected by a flexible polymer connector; the flexible polymer connector is set as Wave-shaped, so that the upper excitation plate has lateral, longitudinal and vertical rectilinear reciprocating margins at the window position; the middle excitation plate, the lower excitation plate, and the actuators are all located outside the water tank.

The structural characteristics of the underwater multi-point excitation pseudodynamic test system of the present invention are also:

The cross-sectional structure of the longitudinal sliding rail is as follows: the "T" shaped sliding rail is symmetrical on both sides, which means that it circles inwards with a rectangular side; the longitudinal sliding block forms a nest with the longitudinal sliding rail in a corresponding shape;

The cross-sectional structure of the transverse slide rail is as follows: the "T" shaped slide rail is symmetrical on both sides and circles inward with a rectangular side; the transverse slide block is nested with the transverse slide rail in a corresponding formation.

go a step further:

There are four groups of incentive mechanisms, which are the first incentive mechanism, the second incentive mechanism, the third incentive mechanism and the fourth incentive mechanism from left to right. The longitudinal actuators of the first and second incentive mechanisms Located at the left end of the water tank, the longitudinal actuators of the third excitation mechanism and the fourth excitation mechanism are located at the right end of the water tank;

The fourth longitudinal actuator for driving the fourth excitation mechanism is linked with the lower excitation plate in the fourth excitation mechanism through a straight rod;

The longitudinal actuators used to drive the third excitation mechanism are a pair of third longitudinal actuators acting synchronously, and a "Y"-shaped transmission rod is provided, and the straight rod end of the "Y"-shaped transmission rod is connected to the third The lower excitation plate of the excitation mechanism is connected, and the "V"-shaped rod ends of the "Y"-shaped transmission rod are respectively connected with the pair of third longitudinal actuators.

go a step further:

To set the limit structure, a bowl-shaped cover is fixed on the side of the upper excitation plate, and a sliding plate is placed in the inner cavity of the bowl-shaped cover. The steel ball; the transmission rod connected with the transverse actuator is fixedly connected to the plane of the outer plate of the sliding plate; the bowl-shaped cover pushes the sliding plate against the side of the upper excitation plate along the action direction of the transverse actuator to avoid The sliding plate forms a movement between the upper excitation plate along the force direction of the transverse actuator; the sliding plate located in the bowl-shaped cover can translate arbitrarily on a plane perpendicular to the force direction of the transverse actuator; A cover hole of sufficient size is set on the cover plate of the bowl-shaped cover, and the transmission rod connected with the transverse actuator passes through the cover hole. The cover hole not only meets the translation of the sliding plate in the bowl-shaped cover, but also ensures The upper excitation board does not come off.

Compared with the prior art, the beneficial effects of the present invention are reflected in:

1. The present invention can not only meet the size requirements of large-scale structural models, but also reproduce earthquake motion and structural response, and provide a powerful means for studying the seismic response mechanism and seismic design of underwater slender structures.

2. The present invention can be used to realize underwater multi-point differential input earthquake simulation experiments, and realize synchronous or asynchronous displacement loading under given seismic parameters, thereby simulating the dynamic response of the underwater structure positioned on the excitation mechanism under the action of seismic waves.

3. The present invention sets linear electro-hydraulic servo actuators, and each actuator can be independently controlled by a single-chip microcomputer, which can realize synchronous or asynchronous load and displacement, and can not only simulate the underwater structure fixed on the excitation plate under the action of seismic waves The lower dynamic response, and greatly save the test cost.

4. The system of the present invention can set control parameters for each independent control system as required under the control of a computer, thereby completing a given waveform test.

Description of drawings

Fig. 1 is a structural representation of the present invention;

Fig. 2 is a schematic diagram of anchor cable positioning structure in the present invention;

Fig. 3 is a schematic diagram of the connection structure between the upper excitation plate and the bottom plate of the water tank in the present invention;

Fig. 4 is the front view of the excitation mechanism in the present invention;

Fig. 5 is a side view of the excitation mechanism in the present invention;

Fig. 6a is a schematic diagram of the transmission rod of the longitudinal actuator of the present invention;

Fig. 6b is a schematic diagram of another form of the transmission rod of the longitudinal actuator of the present invention;

Fig. 7 is a schematic diagram of the rolling support limit structure set for the excitation plate in the present invention;

Labels in the figure: 1 support, 2 water tank, 3 suspension tunnel model, 4 pipe section connector, 5 wave-eliminating filter, 6 anchor cable, 7 flexible polymer connector, 8 sealing rubber strip, 9 excitation mechanism, 10a "Y ”-shaped transmission rod, 10b straight rod, 11 transverse actuator, 12 vertical actuator, 13 longitudinal actuator, 13a third longitudinal actuator, 13b fourth longitudinal actuator, 14 connecting rod, 15 water tank Base plate, 16a vertical slide block, 16b vertical slide rail, 16c horizontal slide block, 16d horizontal slide rail, 17 spring, 18 bowl-shaped cover, 19 sliding plate, 20 steel balls.

Detailed ways

In this embodiment, the underwater multi-point excitation pseudodynamic test system is aimed at the floating tunnel model 3 in water, and can also be applied to the floating tunnel model composed of a single or multiple pipelines. The floating tunnel model 3 adopts PVC circular pipelines, according to the suspended It is required to add lead rings for counterweight, and the water level in the water tank should be higher than the top of the floating tunnel model 3 during the test.

Referring to Fig. 1, Fig. 2, the transparent water tank 2 that is filled with water body is set in the present embodiment, and the bottom plate 15 of water tank is planar structure, and is supported by support 1; In water tank 2, the floating tunnel model 3 in the water that is suspended in the water body is set; The excitation mechanism 9 is arranged horizontally below the floating tunnel model 3 in the water, and the excitation mechanism 9 and the floating tunnel model 3 in the water are connected with the anchor cable 6; multiple sets of excitation mechanisms 9 are arranged at intervals along the longitudinal direction, and the anchor cable 6 is connected between each group of the excitation mechanism 9 and the floating tunnel model 3 in the water. The excitation points on the water suspension tunnel model 3 are connected in one-to-one correspondence to form a multi-point excitation mechanism; a driving mechanism is provided to drive the linear reciprocating motion of the excitation mechanism 9 in the horizontal, vertical and vertical directions; the longitudinal direction refers to The direction parallel to the axis of the floating tunnel model 3 in the water.

The underwater floating tunnel model 3 shown in Fig. 1 is a left-right symmetric structure formed by connecting the left-section model and the right-section model with the pipe section connector 4 in the middle; the multi-point excitation mechanism is left-right symmetry corresponding to the left-section model and the right-section model Distribution; at the water surface position of the experimental water tank, a wave-eliminating filter screen 5 is installed on each periphery of the water tank, and the bottom of the wave-eliminating filter screen 5 is inclined towards the inside of the water tank. The grid is from the inner layer to the outer layer from small to large, and is used to absorb the waves generated by the water surface vibration caused by the dynamic action during the experiment. For the convenience of expression, only the wave-eliminating filter 5 is shown on the left side of the water tank. hint.

Referring to Fig. 4, Fig. 5 and Fig. 6, the excitation mechanism 9 in this embodiment is a three-layer excitation plate, which are respectively the lower excitation plate 9c supported by the spring 17 at the bottom, the longitudinal slide rail 16b and the longitudinal slide block 16a arranged in cooperation The middle excitation plate 9b supported on the top surface of the lower excitation plate 9c, and the upper excitation plate 9a supported on the top surface of the middle excitation plate 9b with the transverse slide rail 16d and the transverse slide block 16c arranged in cooperation; the anchor cable 6 is positioned and connected to the upper Excitation board 9a. As shown in Figure 3, a series of connecting rods 14 are arranged at intervals on the upper excitation plate 9a, and connecting points are respectively set on each connecting rod 14. To change the traction angle of the anchor cable by changing the fixed position of the anchor cable, and to carry out experimental research on different anchor cable arrangements.

As shown in Figure 1, the driving mechanism is corresponding to the three-layer excitation plate, and each actuator is independently provided, which are respectively the transverse actuator 11 for driving the upper excitation plate 9a to move horizontally and linearly, and the transverse actuator 11 for driving the middle excitation plate 9b to move vertically and linearly. A reciprocating longitudinal actuator 13, and a vertical actuator 12 for driving the lower excitation plate 9c to reciprocate vertically.

As shown in Fig. 1 and Fig. 3, in this embodiment, a window is provided on the bottom plate 15 of the water tank, and the upper excitation plate 9a is placed in the window of the bottom plate 15 of the water tank, and the periphery of the upper excitation plate 9a and the periphery of the window are connected by flexible polymer connectors. 7 is sealed and connected by a sealing strip 8; the flexible polymer connector 7 is arranged in a wave shape as shown in Figure 3, so that the upper excitation plate 9a has a lateral, longitudinal and vertical rectilinear reciprocating motion allowance at the window position; The middle excitation plate 9b, the lower excitation plate 9c, and the actuators are located outside the water tank, and the water tank 2 is supported by the support 1 at an appropriate height to ensure that the middle excitation plate 9b, the lower excitation plate 9c, and each actuator installation and operating position.

The cross-sectional structure of the longitudinal slide rail 16b shown in Figure 5 is: the "T" shaped slide rail is symmetrical on both sides and circles inwardly with a rectangular side; the longitudinal slide block 16a forms a nest with the longitudinal slide rail 16b in a corresponding shape; The cross-sectional structure of the transverse slide rail 16d shown in FIG. 4 is: the "T" shaped slide rail is symmetrical on both sides and circles inwardly with a rectangular side; Such a structural form enables the excitation plates of each layer to be accurately guided and slide freely along the direction of their respective slide rails. When the actuators act in different directions at the same time, the lower excitation plate drives the middle excitation plate and then the upper excitation plate. The multi-dimensional movement of the board avoids the mutual influence between different directions.

There are four groups of incentive mechanisms 9 in this embodiment, which are the first incentive mechanism, the second incentive mechanism, the third incentive mechanism and the fourth incentive mechanism from left to right. The actuator is located at the left end of the water tank, and the longitudinal actuators of the third and fourth excitation mechanisms are located at the right end of the water tank;

The fourth longitudinal actuator 13b used to drive the fourth excitation mechanism is linked with the lower excitation plate in the fourth excitation mechanism through the straight rod 10b shown in Figure 6a;

The longitudinal actuators used to drive the third excitation mechanism are a pair of synchronously acting third longitudinal actuators 13a, which are provided with a "Y"-shaped transmission rod 10a as shown in Figure 6b, and the straight line of the "Y"-shaped transmission rod 10a The rod end is connected with the lower excitation plate of the third excitation mechanism, and the "V"-shaped rod end of the "Y"-shaped transmission rod 10a is respectively threaded with a pair of third longitudinal actuators 13a; this structural arrangement makes a pair of the first The three longitudinal actuators 13a and the fourth longitudinal actuator 13b can be arranged on the same plane and avoid mutual interference.

In the specific implementation, as shown in Figure 7, the above excitation plate 9a is taken as an example, in order to enable the upper excitation plate 9a to obtain the excitation of vertical reciprocating motion and when obtaining the excitation of longitudinal reciprocating motion, the horizontal actuator connected to it 11 does not form a follow-up in the vertical and longitudinal directions, and a limit structure can be provided. A bowl-shaped cover 18 is fixedly installed on the side of the upper excitation plate 9a, and a sliding plate 19 is placed in the inner cavity of the bowl-shaped cover 18 to slide. Steel balls 20 that can be centered and rolled are arranged in an array on the two side plate planes of the plate 19; the transmission rod connected with the transverse actuator 11 is fixedly connected on the outer plate plane of the sliding plate 19; In the action direction of the transverse actuator 11, the sliding plate 19 is pressed against the side of the upper excitation plate, so as to avoid the movement of the sliding plate 19 and the upper excitation plate 9a in the direction of the force of the transverse actuator 11; The sliding plate 19 positioned in the bowl-shaped cover 18 can translate arbitrarily on a plane perpendicular to the force direction of the transverse actuator 11; a cover hole of sufficient size is provided on the cover plate of the bowl-shaped cover 18, and the horizontal actuator 11. The transmission rod connected with each other runs through the cover hole, and the cover hole should not only satisfy the translation of the sliding plate in the bowl-shaped cover, but also ensure that the sliding plate does not separate from the upper excitation plate. Moreover, the structure of the middle excitation plate 9b on the side where the longitudinal actuator 13 is located is the same as that shown in FIG. 7 .

In the specific implementation, the input of the power signal can be realized by the MTS material testing machine, which adopts the force-displacement control mode and realizes the power loading through the electro-hydraulic servo actuator. The actuator either passes through the transmission rod or directly acts on the corresponding excitation plate. Above all, each actuator is controlled independently, which can realize synchronous or asynchronous load and displacement, and then realize the multi-point and multi-dimensional vibration test of the underwater structure fixed on the excitation plate along one or more directions.

This embodiment takes the floating tunnel in water as a model, and the corresponding structural settings can also be aimed at various underwater slender structures in oil and natural gas exploitation.

Claims (5)

1. An underwater multi-point excitation pseudodynamic test system is provided with a transparent water tank (2) filled with water supported by a support (1), and the bottom plate of the water tank (15) is a plane structure; a suspension is set in the water tank (2). The underwater suspension tunnel model (3) in the water body; the incentive mechanism (9) is horizontally set under the underwater suspension tunnel model (3), and the excitation mechanism (9) is connected with the underwater suspension with an anchor cable (6). Tunnel model (3); multiple groups of excitation mechanisms (9) are arranged at intervals along the longitudinal direction, and anchor cables (6) are connected one by one between each group of excitation mechanisms (9) and each excitation point on the underwater floating tunnel model (3) , forming a multi-point excitation mechanism; a drive mechanism is provided for driving the linear reciprocating motion of the excitation mechanism (9) in the horizontal, vertical and vertical directions; It is characterized in that: the excitation mechanism (9) is a three-layer excitation plate, which is respectively a lower excitation plate (9c) supported by a spring (17) at the bottom, and a longitudinal slide rail (16b) arranged in conjunction with ) and the longitudinal slider (16a) are supported on the middle excitation plate (9b) on the top surface of the lower excitation plate (9c), and are supported on the middle excitation plate ( 9b) the upper excitation plate (9a) on the top surface; the anchor cable (6) is positioned and connected to the upper excitation plate (9a); the drive mechanism is independently provided with each actuator corresponding to the three-layer excitation plate, respectively A transverse actuator (11) for driving the upper excitation plate (9a) to move horizontally and linearly, a longitudinal actuator (13) for driving the middle excitation plate (9b) to move vertically and linearly, and a longitudinal actuator (13) for driving the lower excitation plate (9a). Vertical actuator (12) for vertical reciprocating movement of plate (9c). 2. the underwater multi-point excitation pseudodynamic test system according to claim 1 is characterized in that: a window is provided on the water tank bottom plate (15), and the upper excitation plate (9a) is placed on the bottom of the water tank bottom plate (15) In the window, the periphery of the upper excitation plate (9a) is closed and connected with the periphery of the window through a flexible polymer connector (7); the flexible polymer connector (7) is set in a wave shape, so that the upper excitation plate ( 9a) There are lateral, longitudinal and vertical rectilinear reciprocating allowances at the window position; the middle excitation plate (9b) and the lower excitation plate (9c), as well as the actuators are all located outside the water tank. 3. the underwater multi-point excitation pseudodynamic test system according to claim 1, is characterized in that: The cross-sectional structure of the longitudinal slide rail (16b) is: the "T" shaped slide rail is symmetrical on both sides and circles inwardly with a rectangular side; ) form nesting; The cross-sectional structure of the transverse slide rail (16d) is: the "T" shaped slide rail is symmetrical on both sides and circles inwardly with a rectangular side; ) form a stack. 4. the underwater multi-point excitation pseudodynamic test system according to claim 1, is characterized in that: There are four groups of the incentive mechanism (9), which are the first incentive mechanism, the second incentive mechanism, the third incentive mechanism and the fourth incentive mechanism from left to right, and the longitudinal direction of the first incentive mechanism and the second incentive mechanism is The actuator is located at the left end of the water tank, and the longitudinal actuators of the third and fourth excitation mechanisms are located at the right end of the water tank; The fourth longitudinal actuator (13b) for driving the fourth excitation mechanism is linked with the lower excitation plate in the fourth excitation mechanism through a straight rod (10b); The longitudinal actuators used to drive the third excitation mechanism are a pair of synchronously acting third longitudinal actuators (13a), and a "Y"-shaped transmission rod (10a) is provided, and the "Y"-shaped transmission rod (10a) The straight end of the straight rod is connected with the lower excitation plate of the third excitation mechanism, and the "V"-shaped rod end of the "Y"-shaped transmission rod (10a) is connected with the pair of third longitudinal actuators (13a) respectively. connect. 5. the underwater multi-point excitation pseudodynamic test system according to claim 1 is characterized in that: a position-limiting structure is set, and a bowl-shaped cover (18) is fixedly arranged on the side of the upper excitation plate (9a), A slide plate (19) is placed in the inner cavity of the bowl-shaped cover (18), and steel balls (20) that can be centered and rolled are respectively arranged in an array on the two side plate planes of the slide plate (19); 11) The connected transmission rods are fixedly connected on the plane of the outer plate of the sliding plate (19); the bowl-shaped cover (18) pushes the sliding plate (19) against the upper excitation along the direction of action of the transverse actuator (11). The side of the plate prevents the sliding plate (19) from forming in the force direction along the transverse actuator (11) and the upper excitation plate (9a); the sliding plate located in the bowl-shaped cover (18) (19) can translate arbitrarily on the plane perpendicular to the force direction of transverse actuator (11); Offer the cover hole of sufficient size on the cover plate of bowl-shaped cover (18), and transverse actuator (11) The connected transmission rod runs through the cover hole, and the cover hole not only satisfies the translational movement of the sliding plate in the bowl-shaped cover, but also ensures that the sliding plate does not separate from the upper excitation plate.