CN103454103B - Loading device for geotechnical engineering large-sized three-dimensional comprehensive simulation test bed - Google Patents

Abstract

A loading device for a large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering, including a reaction wall and a reaction beam. The reaction wall is made of reinforced concrete and has a double-layer structure. There is a human operator between the double-layer reaction walls Channel, the control pipeline penetrates between the double-layer reaction walls through the horizontal installation holes reserved on the reaction walls, and is connected to the control room of the ground test building; The simulation test bench is arranged on the upper end surface of the reaction wall and is fixedly connected with the reaction wall. The invention provides a loading device for a large-scale three-dimensional comprehensive simulation test bench of geotechnical engineering that can realize true three-dimensional loading, which can be used for simulation tests of underground space and its excavation, foundation and slope engineering simulation tests under the conditions of rainfall and groundwater level rise and fall , dynamic response test of pile foundation and pile surrounding soil, segment simulation test, performance test of structural components and other geotechnical test simulations with different functions.

Description

Loading device for large-scale three-dimensional comprehensive simulation test bench of geotechnical engineering

technical field

The invention relates to a physical model test device which can be used in geotechnical engineering such as tunnels and subway stations, foundation engineering, slope engineering, retaining structures, etc., especially a test platform which can carry out three-dimensional comprehensive simulation tests on large-scale geological models. In particular, it relates to a loading device used for a large-scale three-dimensional comprehensive simulation test bench of geotechnical engineering.

Background technique

Physical model test is an important means to study large-scale geotechnical engineering problems. It is widely used at home and abroad, and plays an important role in engineering research and design. Scholars at home and abroad have carried out fruitful research work on engineering issues such as the stability of the surrounding rock of the roof of the large mine, the stability of the rock mass of the dam body and the dam foundation, the stability and support of the surrounding rock of the large cavern, and have developed supporting models of various scales. test equipment.

Existing various test devices for physical model tests are often specially designed and developed for specific projects, and can only simulate a certain type of underground project, which is not universal. Moreover, for geotechnical engineering model experiments, the geometric similarity ratio of the experimental model is a key technical index. If the geometric similarity ratio is too small, although the experimental materials can be saved, the too small model volume will limit the arrangement of sensors. Compared with the larger model, it is more likely to be disturbed by external factors, thus affecting the experimental results. Therefore, when conditions permit, a larger model geometric similarity ratio should be used as much as possible. In this case, the complexity of the model experiment itself will increase accordingly. For example, large-scale model experiments require a large amount of similar materials; when simulating complex working conditions with large buried depths, a large-tonnage loading system and a high-rigidity reaction system are required. With the increasing scale of geotechnical engineering and the more complex engineering problems, the existing model test equipment can no longer meet the needs of engineering practice.

In the following explanations of the present invention, the so-called three-dimensional comprehensive simulation test refers to the implementation of true triaxial loading, the simulation test of underground space and its excavation, the foundation and slope engineering simulation test under the conditions of rainfall and groundwater level rise and fall , dynamic response test of pile foundation and pile surrounding soil, segment simulation test, structural component performance test and other physical model tests with different functions. Model maximum size can reach 10m * 6m * 6m (length * width * height), compared with the model test scale of prior art, it is much larger in size, so test bench of the present invention is relative to aforementioned prior art Belongs to a large test platform.

Chinese patent CN202033951U provides a geotechnical engineering physical simulation testing machine, which adopts a steel frame structure placed on the ground, which can be used for geomechanical model tests on caverns and cavern slopes, but can only test the top, bottom, left, and right sides of the model. Loading in one direction, the model cannot be loaded in true triaxial. Moreover, the test machine is placed on the ground, and its scale is small, so it cannot be used for large-scale physical model tests.

Chinese patent CN100535267C provides a kind of foundation and slope engineering model test platform, the model box of the test platform announced by this patent is placed on the surrounding closed steel structure on the ground, although large-scale model tests can be carried out, but only for the model Loading is carried out at the top and cannot be used for physical model tests of excavation works such as tunnels and subway stations.

Contents of the invention

The technical problem to be solved by the present invention is to provide a loading device for a large-scale three-dimensional comprehensive simulation test bench of geotechnical engineering, so as to reduce or avoid the problems mentioned above.

Specifically, the present invention provides a loading device for a large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering, the large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering at least includes a loading device and a model box, and the loading device includes a Reaction walls for horizontal loading and reaction beams for vertical loading;

The reaction wall is made of reinforced concrete and is arranged around the four perimeters of the foundation pit excavated from the ground; the reaction wall is a double-layer structure, and cross braces and personnel are arranged between the double-layer reaction walls. An operation channel, the control pipeline of the horizontal loading cylinder penetrates between the double-layer reaction walls through the horizontal installation hole reserved on the reaction wall, and is connected to the control room of the ground test building;

The reaction beam is arranged on the upper end surface of the reaction wall across the large-scale three-dimensional comprehensive simulation test platform of geotechnical engineering, and is fixedly connected with the steel structure components poured in the concrete inside of the reaction wall;

The surrounding and top of the model box are spliced by multiple loading plates, and the bottom of the model box shares the bottom reinforced concrete ground with the foundation pit; the inner reaction wall is evenly arranged with multiple reserved horizontal installation holes; each Each horizontal loading plate is connected with a horizontal loading oil cylinder through a spherical joint, and the horizontal loading oil cylinder is fixedly connected with the reaction wall through a connecting bolt arranged in the horizontal mounting hole; each vertical loading plate is connected through a spherical joint Connected with a vertical loading cylinder, each of the vertical loading cylinders is fixedly connected with the reaction beam through connecting bolts;

Bolt holes are reserved between the side surfaces of the adjacent horizontal loading plates, and bolted connections may be carried out depending on the needs of the test.

Preferably, the horizontal loading plate has a panel in contact with the model, the periphery of the panel has side panels perpendicular to the panel, the panel and the side panels are connected by stiffeners, and the stiffeners There are two diagonal ribs, two middle ribs and surrounding ribs arranged parallel to the side panels, and a connecting plate is arranged in the middle of the reinforcing ribs.

The invention proposes a loading device for a large-scale three-dimensional comprehensive simulation test bench of geotechnical engineering, which can be used for underground space and its excavation simulation test, foundation and slope engineering simulation test under the conditions of rainfall and groundwater level rise and fall, pile foundation and Physical model tests with different functions such as dynamic response test of soil around the pile, segment simulation test, performance test of structural components, etc. At the same time, the application of the loading device can realize true three-dimensional loading of large-scale physical models.

Description of drawings

The following drawings are only intended to schematically illustrate and explain the present invention, and do not limit the scope of the present invention. in,

What Fig. 1 shows is the three-dimensional structure schematic diagram of a kind of geotechnical engineering large-scale three-dimensional comprehensive simulation test bench according to a specific embodiment of the present invention;

Figure 2 shows a schematic cross-sectional view of Figure 1;

What Fig. 3 shows is the longitudinal sectional schematic diagram of Fig. 1;

What Fig. 4 shows is a schematic top view of a model box according to a specific embodiment of the present invention;

Figure 5 shows an enlarged schematic view at position B in Figure 4;

Figure 6 shows a schematic exploded view of the enlarged structure of the horizontal loading plate and the horizontal loading cylinder connected thereto;

Fig. 7 shows a schematic diagram of the three-dimensional structure of the horizontal loading plate.

Detailed ways

In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific implementation manners of the present invention will now be described with reference to the accompanying drawings. Wherein, the same parts adopt the same reference numerals.

What Fig. 1 shows is the three-dimensional structure schematic diagram of a kind of geotechnical engineering large-scale three-dimensional comprehensive simulation test-bed proposed according to a specific implementation case of the present invention, and what show roughly among the figure is the large-scale three-dimensional comprehensive simulation test-bed of geotechnical engineering of the present invention The general structure highlights the main differences between it and the prior art mentioned in the relative background art section.

Referring to Fig. 1, a significant difference between the large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering of the present invention and the prior art is that the main part of the large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering of the present invention is arranged in a foundation pit excavated on the ground 1 (see FIGS. 2 and 3), wherein, the part indicated by the reference numeral 11 in FIG. 1 is the ground, and the part indicated by the reference numeral 12 is the bottom of the foundation pit 1. What Fig. 2 shows is the cross-sectional schematic diagram of Fig. 1, and what Fig. 3 shows is the longitudinal cross-sectional schematic diagram of Fig. 1, of course, similar to Fig. 1, what Fig. 2, Fig. 3 adopt is the simple drawing method, only for this field Technician reading comprehension.

As shown in Figures 1-3, the geotechnical engineering large-scale three-dimensional comprehensive simulation test bench of the present invention generally includes an underground part located in the foundation pit 1 and an aboveground part arranged around the foundation pit 1, wherein the underground part is the main body of the test platform structure, including at least a loading device 2 and a model box 3 (the model box 3 is not shown in Figs. force beam 22. That is, the geotechnical engineering large-scale three-dimensional comprehensive simulation test bench of the present invention at least includes a reaction wall 21 providing horizontal loading force, a reaction beam 22 providing vertical loading force, and a model box 3 .

Wherein, the reaction force wall 21 is made of reinforced concrete, and is arranged around the four peripheries of the foundation pit 1 excavated by the ground; the ground 11 around the foundation pit 1 is provided with a ground test building 13 (a part is shown in Fig. 1 , concrete structure is referring to Fig. 2,3), the top of ground test building 13 has the movable crane 14 that straddles foundation pit 1; One side of foundation pit 1 has a material delivery elevator shaft 15 that communicates with ground 11; A test channel 16 is arranged on the reaction wall 21 on the side corresponding to the elevator shaft 15 , and the test channel 16 communicates with the material conveying elevator shaft 15 .

There are two reaction beams 22 shown in FIG. 1 , which are arranged on the upper end surface of the reaction wall 21 and are fixedly connected with the steel structure components (not shown) poured in the concrete inside of the reaction wall 21 . The model box 3 is arranged in the space surrounded by the reaction wall 21 and the reaction beam 22 .

The reaction beam 22 is used to load the top of the model. Only two reaction beams 22 are shown in Figure 1, and only one reaction beam 22 is shown in Figure 3. Figures 1-3 are only schematic. In actual use, A plurality of reaction force beams 22 can be set according to the size of the model box 3 and the top pressure to be borne, and the two ends of the reaction force beams 22 are connected to the top of the reaction force wall 21 by bolts.

It can be seen from the above that the significant difference between the large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering of the present invention and the prior art is that the test part of the large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering of the present invention, that is, the loading device 2 is mainly arranged underground , while the existing test platforms are all set on the ground. In the present invention, the main force-applying and force-receiving parts, mainly the reaction wall 21 and its subsidiary reinforced concrete structure, are arranged in the underground foundation pit 1, and are backed against the periphery of the foundation pit 1, so that the force and force are applied and received during the test. The parts of force are firmly embedded in the ground, which can ensure that the reaction force wall 21 possesses sufficient strength and rigidity. In addition, since the reaction force wall 21 is arranged around the four peripheries of the foundation pit 1 excavated from the ground, and it is surrounded and connected as a whole, when the force is applied to the model box through the four sides of the reaction force wall 21 at the same time, The reaction forces on the opposite reaction walls 21 can cancel each other out to form a self-balancing system. Moreover, since the reaction wall 21 and its attached reinforced concrete structure are backed against the four sides of the foundation pit 1, the soil around the test platform will exert a certain reaction force on the reaction wall, which will effectively reduce the deformation of the reaction wall and significantly improve the test platform. anti-overturning ability.

On the other hand, the reaction wall 21 is arranged in the underground foundation pit 1, which saves the above-ground space, and at the same time facilitates the test personnel to provide test assistance and observe the test process from the ground during the test process.

Another notable feature of the large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering of the present invention is the enlargement of its structural size. The maximum model size in the present invention can reach 10m × 6m × 6m (length × width × height). In terms of the scale of technical model tests, the size is relatively larger, which is convenient for model tests of various projects and different working conditions. In order to solve the large-scale problem, the present invention not only arranges the main test structure underground, but also carries out further structural improvements accordingly, for example, a large rigidity loading device is provided by the reaction wall 21 of the double-layer prestressed reinforced concrete structure , so as to provide a large tonnage loading system.

Additionally, for large tests, the delivery of model material can become especially difficult. Since the large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering of the present invention is set in a fixed building, it is impossible to use movable equipment such as a crane to lift and load materials like the existing open steel frame structure. Conveying materials, therefore, the geotechnical engineering large-scale three-dimensional comprehensive simulation test bench of the present invention is provided with the movable crane 14 that straddles the foundation pit 1 on the top of the ground test building 13 around foundation pit 1, is used for by hook or grabs The bucket transports the material. In addition, in order to facilitate personnel to enter and exit the foundation pit 1 to set up and install test equipment, a material delivery elevator shaft 15 is also provided on one side of the foundation pit 1 for transporting personnel or small-scale test equipment and model materials through the elevator shaft 15. Further, since large-scale tests need to transport a large amount of model materials, in a specific embodiment, a conveyor belt 17 is provided on the upper part of the foundation pit 1 to deliver model materials to the model box. Obviously, the settings of these structures are improvements proposed to meet the needs of large-scale model tests. In the prior art, for the open test platform located on the ground, there is no need to use the material conveying elevator shaft 15, the conveyor belt 17, and the ground test building 13. Structures such as the crane 14 on the top.

In order to install structures such as horizontal loading actuators that provide horizontal loading force as shown in FIG. A plurality of horizontal loading holes 23 are evenly distributed on the top; As can be seen from Figures 2 and 3, a part of the horizontal loading holes 23 is a through hole, and a part is a blind hole, and the distribution of the through hole and the blind hole is pre-designed according to the needs of the test. Those skilled in the art should understand that when the horizontal loading hole 23 is a through hole, it can also be used for laying cables, water pipes, sensor cables, oil pipelines and other pipelines.

As shown in Figure 4, it shows a schematic top view of a model box 3 according to a specific embodiment of the present invention, wherein the model box 3 can be spliced into four peripheries of the model box 3 by a plurality of horizontal loading plates 31, Similarly, similar to the top view of the model box 3 shown in Figure 4, a plurality of vertical loading plates are spliced into the top of the model box, and the bottom of the model box 3 shares the bottom with the large-scale three-dimensional comprehensive simulation test bench for geotechnical engineering Reinforced concrete floor.

Each of the horizontal loading plates 31 is connected with a horizontal loading actuator 32, and the horizontal loading actuator 32 is fixedly connected with the reaction wall 21 through the connecting bolts arranged in the horizontal loading holes 23; Similarly, similar to the top view of the model box 3 shown in Figure 4, each of the vertical loading plates is connected with a vertical loading actuator, and each of the vertical loading actuators is connected to the reaction force by connecting bolts. Beam 22 is fixedly connected. The structure of connecting the horizontal loading plate 31 and the horizontal loading oil tank 32 through a spherical joint can be referred to the enlarged view shown in FIG. 6 .

Regarding the structure of the model box 3, its biggest difference from the prior art is that the model box 3 is spliced by a plurality of horizontal loading plates 31 and vertical loading plates, which are set up to meet different scales and different loading methods. The need for model testing. For example, for models of different sizes, it is necessary to provide loading plates of different sizes. Using the loading plate splicing structure of the present invention can easily splice load plate combinations of different sizes to meet the requirements of model tests of different sizes.

Because the model box 3 is spliced by a plurality of loading plates, therefore, before making the model, the horizontal loading plate 31 can only be installed on three sides of the model box 3, and the loading plate can not be installed near the test channel 16 side, and then the conveyor belt 17 Installed at the test channel 16, so that the model material can be transported underground by the elevator 15, and then directly transported into the model box 3 space via the conveyor belt 17, the soil layer is arranged in layers according to the design, and the layered installation depends on the load on the side of the test channel 16. Plates and upper model materials can be transported by installing a grab machine on the crane until the entire test body is formed.

On the other hand, the present invention adopts the structure of splicing loading plates, and each loading plate provides an independent loading oil cylinder, which can provide any combination of mechanical loading models in conjunction with each loading plate, which is different from the existing Technology CN100535267C and CN202033951U are somewhat similar, although these prior art provide a plurality of loading oil cylinders, but loading plate is an integral structure, can't realize flexibly loading for each model test difference.

In addition, in a preferred embodiment, the reaction force wall 21 is a double-layer structure, and there are cross braces and personnel operation channels 211 between the double-layer reaction force walls 21, and the control pipeline of the horizontal loading actuator passes through the The horizontal loading hole 23 reserved on the reaction wall 21 penetrates between the double-layer reaction walls 21 and is connected to the control room of the ground test building 13 . This setting is to meet the requirements of large-scale model tests. On the one hand, it provides a more rigid reaction wall 21, and on the other hand, it can provide personnel passages for installing and debugging equipment.

What Fig. 5 shows is the enlarged schematic view of position B in Fig. 4; groove, and then insert the sealing strip 311. This can ensure the airtightness between the spliced loading plates of the model box 3, and similarly, a sealing strip can also be embedded between the sides of the adjacent vertical loading plates. In addition, it can be seen from Fig. 5 that bolt holes are provided between the sides of adjacent horizontal loading plates 31, similar to the structure in Fig. 6, adjacent sides of the vertical loading plates may also be provided with Bolt hole. This arrangement is to connect the sides of the adjacent horizontal loading plates by bolts when the test requires, to ensure that each horizontal loading plate 31 is in a vertical state and neatly arranged side by side, so that each horizontal loading plate can be loaded and moved synchronously.

FIG. 6 shows an enlarged exploded view of the horizontal loading plate 31 and the horizontal loading cylinder 32 connected thereto. Those skilled in the art should understand that the relevant structure is actually applicable to the structure of the vertical loading plate and the vertical loading cylinder.

Specifically, each horizontal loading plate 31 is connected to a horizontal loading cylinder 32 through a spherical joint 34, and the horizontal loading cylinder 32 is fixed to the reaction wall 21 through a connecting bolt arranged in the horizontal mounting hole 23 connect. The horizontal and vertical positions of each loading plate can be adjusted before loading by using the spherical joint 34 to ensure that each horizontal loading plate 31 is in a vertical state and arranged neatly side by side, so that each horizontal loading plate can be loaded and moved synchronously.

What Fig. 7 shows is the three-dimensional schematic diagram of the horizontal loading plate, wherein omits structures such as the connecting groove of the sealing strip 311, related structure can be referred to Fig. 5, and described horizontal loading plate 31 has a panel 312 that contacts with model, so The periphery of the panel 312 has a side plate 313 perpendicular to the panel, the panel 312 and the side plate 313 are connected by a rib plate 314, and the rib plate 314 has two diagonal rib plates 3141, two middle The rib plate 3142 and the surrounding rib plate 3143 arranged parallel to the side plate, the middle part of the rib plate 314 has a connecting plate 315 .

As shown in Figure 6, the horizontal loading plate 31 is connected to the horizontal loading cylinder 32 through a spherical joint 34, wherein a spherical joint connecting seat 3151 is connected to the connecting plate 315, and the spherical joint connecting seat 3151 is connected to the spherical joint The base 344 is opposite and clamps the spherical joint 34 between the two. One end of the fixing member 341 is fixedly connected to the spherical joint connection seat 3151 through a bolt, and the other end is connected to the spherical joint base 344 through a bolt. Fixed connection.

Similar to the structure shown in FIG. 7 , the vertical loading plate may also have the above-mentioned similar structure and function, which will not be repeated here.

The invention proposes a loading device for a large-scale three-dimensional comprehensive simulation test bench of geotechnical engineering, which can be used for underground space and its excavation simulation test, foundation and slope engineering simulation test under the conditions of rainfall and groundwater level rise and fall, pile foundation It can simulate soil engineering tests with different functions such as dynamic response test of soil around the pile, segment simulation test, and performance test of structural components. At the same time, it can realize true three-dimensional loading and large-scale physical model tests.

Those skilled in the art should understand that although the present invention is described in terms of multiple embodiments, not each embodiment only includes an independent technical solution. The description in the description is only for the sake of clarity, and those skilled in the art should understand the description as a whole, and understand the present invention by considering the technical solutions involved in each embodiment as being able to be combined with each other to form different embodiments scope of protection.

The above descriptions are only illustrative specific implementations of the present invention, and are not intended to limit the scope of the present invention. Any equivalent changes, modifications and combinations made by those skilled in the art without departing from the concept and principle of the present invention shall fall within the protection scope of the present invention.

Claims (2)

1. The utility model provides a loading device for large-scale three-dimensional comprehensive simulation test platform of geotechnical engineering, large-scale three-dimensional comprehensive simulation test platform of geotechnical engineering includes loading device and mold box at least, loading device is including the counter-force wall that provides horizontal loading power and the counter-force roof beam that provides perpendicular loading power, its characterized in that:

the counterforce wall is made of reinforced concrete and surrounds four peripheries of a foundation pit excavated from the ground; the reaction walls are of double-layer structures, personnel operation channels are arranged between the double-layer reaction walls, and control pipelines of the horizontal loading oil cylinder penetrate between the double-layer reaction walls through horizontal mounting holes reserved on the reaction walls and are connected into a control room of the ground test building;

the reaction beam is arranged on the upper end surface of the reaction wall across the geotechnical engineering large-scale three-dimensional comprehensive simulation test bed and is fixedly connected with a steel structure component poured in concrete of the reaction wall;

the model box is formed by splicing a plurality of horizontal loading plates into four peripheries of the model box, a plurality of vertical loading plates are spliced into the top of the model box, and the bottom of the model box and the foundation pit share the bottom reinforced concrete ground; a plurality of reserved horizontal mounting holes are uniformly distributed on one side wall of each reaction wall at the four peripheries of the foundation pit, which faces the interior of the foundation pit; each horizontal loading plate is connected with a horizontal loading oil cylinder through a spherical joint, and the horizontal loading oil cylinder is fixedly connected with the reaction wall through a connecting bolt arranged in the horizontal mounting hole; each vertical loading plate is connected with a vertical loading oil cylinder through a spherical joint, and each vertical loading oil cylinder is fixedly connected with the counter-force beam through a connecting bolt;

the side surfaces of the adjacent horizontal loading plates are connected through bolts.

2. The loading device according to claim 1, wherein the horizontal loading plate has a face plate contacting the model, the face plate has a side plate perpendicular to the face plate at the periphery, the face plate and the side plate are connected by a reinforcing rib plate, the reinforcing rib plate has two diagonal rib plates, two middle rib plates and a surrounding rib plate arranged parallel to the side plate, and a connecting plate is arranged at the middle part of the reinforcing rib plate.