Parallel strike-slip tectonic deformation supergravity test device and parallel strike-slip tectonic deformation supergravity test method

Abstract

The invention discloses a parallel strike-slip structure deformation supergravity test device and method. The driving units are installed on the bottom plate, the two driving units are arranged in a central symmetry mode, the first curved-surface table is located between the two driving units and fixedly installed in the middle of the bottom plate, the two first fences are fixedly connected to the two ends of the first curved-surface table, and the two driving units make sealing contact with the two sides of the first fences correspondingly. The driving unit, the first curved table and the first enclosure define a strike-slip chamber for placing a strike-slip model; the method comprises the steps that strike-slip models are evenly laid in a strike-slip chamber, the whole device is hoisted into a centrifugal machine, a centrifugal strike-slip simulation test under the supergravity environment is carried out, and the strike-slip models are observed in the simulation test to obtain the deformation characteristics of the strike-slip models. A transmission mode of the servo motor, the speed reducer and the ball screw is adopted, low-speed stable driving under the supergravity can be achieved, and the large-scale and long-duration parallel strike-slip fracture evolution process can be simulated under the supergravity environment.

Description

Technical Field

[0001] The invention belongs to the field of structural physics simulation technology and geomechanics, and specifically relates to a parallel strike-slip structural deformation supergravity test device and method. Background Art

[0002] One of the most notable tectonic features of the earth's crust is the widespread presence of long, nearly straight, and topographically linear strike-slip faults, which are the kinematic result of large-scale mutual movement of plates or blocks on the earth. Strike-slip faults are formed at the boundary between land and ocean transform plates; in an intraplate environment, they are the response of the continental interior to plate collisions. A strike-slip system is a relatively narrow and nearly vertical fault zone, along which two adjacent blocks move laterally and horizontally parallel to the strike of the fault zone. According to incomplete statistics, strike-slip earthquakes account for about 58.2% of the types of destructive continental earthquakes in the world, and because large strike-slip fault zones are generally large in scale, long in extension, and have multiple branch faults, either parallel or intersecting, they have a large impact range. Therefore, the seismogenic structure and rupture pattern of large strike-slip fault zones have long been a hot topic for seismologists at home and abroad. Studying the movement characteristics and tectonic evolution of strike-slip faults and deepening the understanding of the seismogenic mechanism of strong earthquakes in strike-slip faults are extremely necessary for the safety and stability evaluation of large-scale projects crossing fault zones.

[0003] At present, the tectonic physical simulation method is a conventional means to study the geometric characteristics and evolution mechanism of strike-slip structures. The tectonic physical simulation experiment reduces the geological prototype with a large time span and wide spatial distribution with an appropriate time and length ratio to restore the geological process in the laboratory. However, the tectonic physical simulation experiment under normal gravity conditions has inherent defects, lacks suitable simulation materials, and when it comes to tectonic simulations involving rock rheology, there are often significant random errors due to the ineffective suppression of secondary factors, and the test repeatability is poor. The development of ultra-gravity tectonic physical simulation experiments has, to a certain extent, solved the defects of the above-mentioned traditional evaluation methods. The biggest advantage of ultra-gravity centrifuges is that they can strengthen gravity and shorten the simulation experiment time.

[0004] Under hypergravity, centrifugal force simulates the earth's gravity, suitable similar materials are laid in the device, and the control system provides dislocation power to simulate the shear movement between plates. It can complete the simulation of the geological structural deformation process experienced by the area in a larger time scale. By recording the deformation process of the model surface and the internal structure of the geological body, the evolution of the structural deformation in the study area can be reproduced, thereby realizing the evaluation and analysis of the engineering geological stability of the study area. The current strike-slip device is only suitable for the evolution process of a single compression-torsion or tension-torsion strike-slip fault, and cannot simulate the evolution process of the mutual influence of branch parallel faults. The influence of the equipotential surface of the curved surface is not considered, and it is not suitable for scaled physical simulation in a hypergravity environment. It is easy to produce large deviations under low-speed driving under high g values, and it is easy to have a "creeping" phenomenon, resulting in motion lag. Therefore, it is urgent to propose a parallel strike-slip experimental device for structural physical simulation in a hypergravity environment. Summary of the invention

[0005] In order to solve the problems existing in the background technology, the purpose of the present invention is to provide a parallel strike-slip structural deformation supergravity test device and method to solve the problems of small time scale of conventional structural physical simulation, inability to restore the stress field of the real geological environment, lack of physical simulation of the mutual influence of branch parallel faults. Due to its own defects, the traditional physical simulation method has limitations in the direction of geological structure simulation. The present invention is suitable for supergravity environment and can realize the simulation and reproduction of tectonic movement and its evolution process.

[0006] The technical solution adopted by the present invention is: 1. A parallel strike-slip structural deformation supergravity test device: It includes a driving unit, a first curved table, a first enclosure and a base plate; the two driving units are respectively fixedly installed on both sides of the base plate, the two driving units are centrally symmetrically arranged with the center of the base plate as the symmetry axis, the first curved table is located between the two driving units, and the first curved table is fixedly installed in the middle of the base plate, the two first enclosures are fixedly connected to the two ends of the first curved table, the two driving units are respectively in contact with the two sides of the first enclosure, the two driving units, the first curved table and the two first enclosures form a strike-slip chamber for placing a strike-slip model, and the driving unit is used to drive the strike-slip model to slip.

[0007] The driving unit comprises a second curved table, a second enclosure, a motor, a reducer, a movable enclosure and a screw rod; The output shaft of the motor is connected to one end of the output shaft of the reducer, and the other end of the output shaft of the reducer is connected to the lead screw through a coupling, and the two ends of the lead screw are respectively mounted on a lead screw fixed side mounting seat and a lead screw supporting side mounting seat, and the lead screw fixed side mounting seat and the lead screw supporting side mounting seat are both fixedly connected to the base plate, and the movable enclosure is connected to the lead screw movably forward and backward, and the second curved table is connected to the base plate movably forward and backward through a linear guide rail, and the second enclosure and the movable enclosure are fixedly connected to the two ends of the second curved table, and a baffle is connected between the second enclosure and the movable enclosure, and the baffle is fixedly connected to the second curved table, and the motor is used to drive the lead screw to rotate through the reducer, and then realize the forward and backward movement of the movable enclosure, the second enclosure and the second curved table through the lead screw; The first curved platform is movably connected between the second curved platforms of the two drive units, and each first enclosure is movably connected between the second enclosure of one drive unit and the movable enclosure of another drive unit.

[0008] A flange is provided at the bottom of the second curved platform near the first curved platform, and horizontal grooves matching the flange are provided on both sides of the bottom of the first curved platform. The flange of the second curved platform is movably connected to the horizontal groove of the first curved platform.

[0009] A vertical groove is provided at the rear end of the second enclosure and the movable enclosure close to the first enclosure, and a shear block is installed at the vertical groove. The second enclosure and the movable enclosure are sealed and connected to both sides of the first enclosure so as to be movable forward and backward.

[0010] The first curved platform and the two second curved platforms located on both sides of the first curved platform constitute a curved platform, the central axis of the curved platform coincides with the rotation axis of the centrifuge, and the curvature of the cross section of the curved platform is 4000-4500 mm.

[0011] Polytetrafluoroethylene is filled as a sealing filler between the second enclosure and the first enclosure, and between the movable enclosure and the first enclosure.

[0012] 2. A parallel strike-slip structural deformation supergravity test method, comprising the following steps: Step S1, first, evenly lay the strike-slip model material in the strike-slip chamber; The specific method of evenly laying the strike-slip model material in the strike-slip chamber in step S1 is as follows: when the strike-slip model material is a tough material, the material is leveled before the centrifugal strike-slip simulation test. First, the tough material is manually laid in the strike-slip chamber, the device is hoisted into the basket of the centrifuge as a whole and fixed, the centrifuge is started, and it runs for a preset time under a certain hypergravity acceleration value Ng until the tough material is leveled, and the centrifuge stops running, and the brittle material is quickly laid on the tough layer to complete the material laying.

[0013] Step S2: Next, the device is hoisted into a centrifuge as a whole to perform a centrifugal slip simulation test under a hypergravity environment; Step S3: observing the strike-slip model in the strike-slip chamber in the centrifugal strike-slip simulation test to obtain the deformation characteristics of the strike-slip model, and then restore the rupture law of the strike-slip fault under the action of tectonic deformation under real working conditions.

[0014] The centrifugal slip simulation test under the supergravity environment in step S2 is specifically as follows: Firstly, the whole device is hoisted into the hanging basket of the centrifuge and fixed, the centrifuge is started, the centrifugal acceleration of the centrifuge is gradually increased to the preset Ng and maintained for the preset time, and the drive unit is started through the control system under Ng hypergravity. The motor in the drive unit drives the screw to rotate, and then drives the second curved table to move back and forth, so that the strike-slip model placed on the second curved table will slip. During the centrifugal strike-slip simulation test, the displacement of the active enclosure / the second enclosure is monitored in real time through the monitoring system connected to the centrifuge to obtain the deformation rate of the strike-slip model; at the same time, the surface deformation characteristics of the strike-slip model in the hypergravity environment are obtained through an external three-dimensional optical scanning observation system.

[0015] In step S1, the material used in the strike-slip model is one of a brittle material, a ductile material, and a combination of a brittle material and a ductile material. The brittle material and the ductile material are selected as follows: If the strike-slip model uses brittle materials, the uniaxial compressive strength of the brittle materials is obtained according to the following formula: E m / E0=(ρ m / ρ0)×(l m / l0) ×(g m / g0) g m / g0=N Among them, E m is the uniaxial compressive strength of the strike-slip model material; ρ m is the density of the strike-slip model material; g m is the gravitational acceleration of the strike-slip model; l m is the size of the strike-slip model; E0 is the uniaxial compressive strength of the prototype material; ρ0 is the density of the prototype material; g0 is the gravitational acceleration of the strike-slip prototype; l0 is the actual size of the strike-slip prototype; N represents the ratio of the centrifugal acceleration of the model in the hypergravity environment to the normal gravitational acceleration of the prototype.

[0016] If the strike-slip model uses ductile material, the viscosity of the ductile material is obtained according to the following formula: η m / η0=(ρ m / ρ0)×(lm / l0) ×(g m / g0)×(t m / t0) g m / g0=N Among them, η m is the viscosity of the strike-slip model material; t m is the movement time of the strike-slip model; η0 is the viscosity of the prototype material; t0 is the tectonic movement time of the strike-slip prototype.

[0017] In the brittle material-tough material combination, the thickness ratio of the brittle material to the tough material is 1:1 to 1:5.

[0018] The center axis of the curved platform of the device coincides with the rotation axis of the centrifuge. The curved platform is used to provide a curved equipotential surface to ensure that the model material in the test device is in the stress gradient environment of the prototype environment, while preventing it from flowing due to non-test dynamic reasons, eliminating the simulation error of the existing technology. The linear guide and the slider jointly guide the curved platform of the drive unit to move linearly, so that the curved platforms on the left and right sides of the device produce a sliding effect.

[0019] The method of the present invention is applicable to scaled model tests in hypergravity environments. It is necessary to ensure that the test model material and the actual prototype material are physically geometrically similar, dynamically similar, and kinematically similar based on similarity criteria. The Schmoluchowski Number (Sm number) is a dimensionless number that describes the ratio of gravity to cohesive force in a fluid, and the Ramberg Number (Rm number) is a dimensionless number that describes the ratio of gravity to viscous force in a fluid. Under ideal conditions, the Sm number and Rm number of the physical model and geological prototype that meet dynamic similarity should be the same or in the same order of magnitude. Before conducting a scaled model test, it is necessary to calculate the Sm number and Rm number of the prototype material and the test material, and compare whether they are in the same order of magnitude. Meeting this requirement indicates that the two materials have physical similarities under hypergravity. The method of the present invention can determine the relevant geological parameters according to the scope of the study area, and design the corresponding test parameters according to the similar scale. According to the lithology (brittle or tough) of the formation, the properties of the simulated material (brittle or tough) are determined, and the materials used in the strike-slip model are brittle materials, tough materials, and a combination of brittle materials and tough materials; when the strike-slip prototype is a brittle formation, the strike-slip model needs to use brittle materials, and the uniaxial compressive strength of the strike-slip model material is obtained according to the following formula: E m / E0=(ρ m / ρ0)×(l m / l0) ×(g m / g0) gm / g0=N Among them, E m is the uniaxial compressive strength of the strike-slip model material; ρ m is the density of the strike-slip model material; g m is the gravitational acceleration of the strike-slip model; l m is the size of the strike-slip model; E0 is the uniaxial compressive strength of the prototype material; ρ0 is the density of the prototype material; g0 is the gravitational acceleration of the strike-slip prototype; l0 is the actual size of the strike-slip prototype; N represents the ratio of the centrifugal acceleration of the model in the hypergravity environment to the normal gravitational acceleration of the prototype.

[0020] The similarity criterion for ductile formations and ductile materials follows the following similarity criterion formula: η r =ρ r × r ×g r ×t r η m / η0=(ρ m / ρ0)×(l m / l0) ×(g m / g0)×(t m / t0) η m / η0=η r ρ m / ρ0=ρ r ; l m / l0= l r ; g m / g0= g r =N; t m / t0=t r Among them, η r is the viscosity similarity ratio between the model and the prototype; ρ r is the density similarity ratio between the model and the prototype; l r is the length similarity ratio between the model and the prototype; g r is the similarity ratio of gravitational acceleration between the model and the prototype; t r is the similarity ratio of the motion time between the model and the prototype; subscript r represents the similarity ratio; subscript m represents the strike-slip model material; subscript 0 represents the strike-slip prototype material; η m is the viscosity of the strike-slip model material; t m is the movement time of the strike-slip model; η0 is the viscosity of the prototype material; t0 is the tectonic movement time of the strike-slip prototype.

[0021] According to the viscosity of the ductile formation in the study area (usually 1×10 17 ~1023 Pa•s), stratum density and regional geometric size (usually tens to hundreds of kilometers), select the appropriate model size (usually hundreds of millimeters), input the actual prototype known quantity by similarity criterion formula, and reasonably adjust the feasible experimental plan to calculate and determine the viscosity and density of the toughness material (usually silica gel is selected, with a viscosity range of 1×10 4 ~5×10 4 Pa•s), to achieve supergravity N Simulation of prototype structural deformation over trillions of years within tens of minutes at g values.

[0022] The device of the present invention can perform physical simulation of strike-slip tectonic dislocation of geological environment under hypergravity environment. The method utilizes hypergravity technology to achieve the similarity between the model stress field and the prototype stress field. The method of the present invention makes the simulation results more similar to the geological prototype and can reproduce the evolution of structural deformation in the study area. Compared with traditional structural physical simulation methods, the present invention has the advantages of longer simulation time scale, larger regional scale, more restored initial stress field, and higher strength of similar materials. With the advantages of hypergravity technology, the drawbacks of shallow simulation depth and narrow selection range of similar materials under normal gravity test conditions can be solved. At the same time, the high g value can put the model material in the stress environment of the prototype, and the deformation and rupture laws of the prototype can be more restored under the action of structural deformation, which has a high research value.

[0023] The two ends of the device of the present invention are equipped with independently drivable drive units, which adopt the transmission mode of servo motor, reducer and ball screw, and can realize low-speed stable drive under hypergravity; the method of the present invention needs to select similar scale, model material and other experimental parameters according to the similarity criterion, rely on the test device, conduct physical simulation test of parallel strike-slip structure under hypergravity, and conduct data analysis on the simulation results, summarize the test report, and provide important basis for revealing the evolution process of parallel strike-slip fault. The scheme of the present invention can simulate the evolution process of large-scale and long-duration parallel strike-slip fault under hypergravity environment.

[0024] The beneficial effects of the present invention are: 1. The device of the present invention can reveal the causes of regional geological structure formation by recording the deformation process of the surface and internal structure of the parallel strike-slip structure model and the geological body, and provide a physical basis for exploring the deformation mechanism and fracture formation law of parallel strike-slip fault geological structures with a certain depth.

[0025] 2. The curved platform of the device of the present invention is composed of three curved platforms on the left, middle and right sides. Different from the smooth bottom plate of the experimental cavity of the general normal gravity device, the curved platform of the device has a certain curvature radius to ensure that the experimental model located thereon is on the same gravity equipotential surface in the hypergravity environment, and can adapt to the stress gradient requirements of the hypergravity environment.

[0026] 3. The device of the present invention can explore the influence of strike-slip dislocation of parallel faults on field geological deformation for parallel tectonic faults. Through the continuous deformation results of the experimental process, more realistic displacement field and velocity field data can be provided for subsequent research and analysis, and field boundary conditions can be provided for numerical simulation of the corresponding research area.

[0027] 4. The present invention is suitable for the ultra-gravity environment created by the ultra-gravity centrifuge. By adjusting the displacement rate of the curved table through the output mechanism of the device, the evolution process of strike-slip structural deformation in different research areas can be reproduced. With the help of the ultra-gravity environment, structural simulation on a time scale of tens of thousands of years and a regional scale of hundreds of kilometers can be achieved, and the stress field environment of the original geological body can be truly restored, so as to realize further exploration of the physical simulation of geological structural deformation. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the overall structure of the device of the present invention; Figure 2 is a side view of a schematic structural diagram of a drive unit of the present invention; Figure 3 is a top view of the structural schematic diagram of the drive unit of the present invention; Figure 4 It is a schematic diagram of the connection method of the curved table of the present invention; Figure 5 It is a schematic diagram of the connection method of the enclosure of the present invention; Figure 6 It is a flow chart of the parallel strike-slip structural deformation supergravity test method of the present invention.

[0029] In the figure: 1. drive unit; 2. curved table pad; 3. first curved table; 4. first enclosure; 5. bottom plate; 6. tension block; 7. linear guide; 8. second curved table; 9. second enclosure; 10. motor pad; 11. motor; 12. reducer; 13. reducer mounting seat; 14. coupling; 15. screw fixed side mounting seat; 16. movable enclosure; 17. screw; 18. screw support side mounting seat; 19. shear block. DETAILED DESCRIPTION

[0030] The present invention is described in detail below in conjunction with specific implementation cases. The following implementation cases will help those skilled in the art to further understand the present invention, but will not limit the present invention in any form.

[0031] like Figure 1As shown, the device includes a driving unit 1, a first curved table 3, a first enclosure 4 and a base plate 5; the two driving units 1 are fixedly mounted on the left and right sides of the base plate 5, respectively, the axes of the two driving units 1 are parallel, and the two driving units 1 are centrally symmetrically arranged with the vertical center of the base plate 5 as the axis of symmetry, the first curved table 3 is located in the middle of the two driving units 1, and the first curved table 3 is fixedly mounted on the middle part of the base plate 5 through a curved table pad 2, the two first enclosures 4 are fixedly connected to the front and rear ends of the first curved table 3 along the extension direction of the first curved table 3, the two driving units 1 are respectively sealed and contacted with the left and right sides of the first enclosure 4, the two driving units 1, the first curved table 3 and the two first enclosures 4 enclose a strike-slip chamber for placing a strike-slip model, and the driving unit 1 is used to push the second enclosure 9 to move forward and backward to drive the strike-slip model to slip.

[0032] like Figure 2 As shown, the driving unit 1 includes a second curved table 8, a second enclosure 9, a motor 11, a reducer 12, a movable enclosure 16 and a screw 17; The output shaft of the motor 11 is connected to one end of the output shaft of the reducer 12, and the other end of the output shaft of the reducer 12 is connected to one end of the screw 17 through the coupling 14. The two ends of the screw 17 are rotatably mounted on the screw fixed side mounting seat 15 and the screw support side mounting seat 18, respectively. The screw fixed side mounting seat 15 and the screw support side mounting seat 18 are both fixedly connected to the bottom plate 5. The movable enclosure 16 is connected to the screw 17 so as to be movable forward and backward along the axial direction of the screw 17. The second curved table 8 can be moved forward and backward along the axial direction of the screw 17 through the linear guide rail 7. The second enclosure 9 and the movable enclosure 16 are fixedly connected to the front and rear ends of the second curved platform 8 along the extension direction of the second curved platform 8, and a baffle is connected between the second enclosure 9 and the movable enclosure 16, and the baffle is fixedly connected to the second curved platform 8. The baffle is arranged along the front and rear directions of the device, and the motor 11 is used to drive the screw rod 17 to rotate through the reducer 12, and at the same time accurately control the rotation speed of the screw rod 17, thereby realizing the precise forward and backward movement of the movable enclosure 16, the second enclosure 9 and the second curved platform 8 through the screw rod 17; The first curved table 3 is movably connected between the second curved tables 8 of the two drive units 1 , and each first enclosure 4 is movably connected between the second enclosure 9 of one drive unit 1 and the movable enclosure 16 of the other drive unit 1 .

[0033] In specific implementation, Figure 3As shown, the axial direction of the drive unit 1 is vertically arranged with the enclosures 4, 9, and 16. The front-to-back direction of the device of the present invention is parallel to the axial direction of the screw 17, and the left-to-right direction of the device is perpendicular to the axial direction of the screw 17. A linear guide rail 7 is fixedly mounted on the base plate 5, and the second curved table 8 in the drive unit 1 can move forward and backward along the track direction of the linear guide rail 7 through a slider to achieve synchronous forward and backward movement of the second enclosure 9, the movable enclosure 16, and the baffle. The motor 11 and the reducer 12 are fixedly connected to the base plate 5 through the motor pad 10 and the reducer mounting seat 13, respectively. The first curved table 3, the two first enclosures 4, the baffle in the drive unit 1, the second curved table 8, the second enclosure 9, and the movable enclosure 16 form a slip chamber.

[0034] like Figure 4 As shown, a flange is provided at the bottom end of the second curved table 8 close to the first curved table 3, and horizontal grooves matching the flange in the second curved table 8 are provided on both sides of the bottom end of the first curved table 3. The flange of the second curved table 8 can be connected to the horizontal groove of the first curved table 3 by being movably moved forward and backward along the axial direction of the screw rod 17.

[0035] like Figure 5 As shown, a vertical groove is provided at the rear end of the second enclosure 9 and the movable enclosure 16 close to the first enclosure 4, and a replaceable shear block 19 is installed in the vertical groove. The second enclosure 9 and the movable enclosure 16 can be sealed and connected to the left and right sides of the first enclosure 4 by being axially movable forward and backward along the screw rod 17.

[0036] A tension block 6 is also installed on the bottom plate 5 of the device. The tension block 6 tightly contacts the support block and the reducer through screws to support the huge weight generated by the reducer under super gravity, thereby reducing the load on the fixing screws of the reducer.

[0037] When the centrifuge is rotating, the first curved table 3 and the two second curved tables 8 located on both sides of the first curved table 3 constitute a curved platform. The central axis of the curved platform coincides with the rotation axis of the centrifuge. The radius of curvature of the cross section of the curved platform is determined by the distance from the rotation center of the centrifuge to the center of the curved table. The curvature of the cross section of the curved platform is 4000~5000 mm.

[0038] The curved platform is a strip-shaped structure whose cross section is always consistent in its own extension direction, and the cross section of the curved platform is specifically a curved surface perpendicular to the extension direction of the curved platform itself.

[0039] The materials used in the strike-slip model are brittle materials, ductile materials, and a combination of brittle materials and ductile materials. If the strike-slip model uses brittle materials, the uniaxial compressive strength of the strike-slip model material is obtained according to the following formula: E m / E0=(ρ m / ρ0)×(l m / l0) ×(g m / g0) g m / g0=N Among them, E m is the uniaxial compressive strength of the strike-slip model material; ρ m is the density of the strike-slip model material; g m is the gravitational acceleration of the strike-slip model; l m is the size of the strike-slip model; E0 is the uniaxial compressive strength of the prototype material; ρ0 is the density of the prototype material; g0 is the gravitational acceleration of the strike-slip prototype; l0 is the actual size of the strike-slip prototype; N represents the ratio of the centrifugal acceleration of the model in the hypergravity environment to the normal gravitational acceleration of the prototype.

[0040] If the strike-slip model uses ductile materials, the viscosity of the strike-slip model material is obtained according to the following formula: η m / η0=(ρ m / ρ0)×(l m / l0) ×(g m / g0)×(t m / t0) g m / g0=N Among them, η m is the viscosity of the strike-slip model material; t m is the movement time of the strike-slip model; η0 is the viscosity of the prototype material; t0 is the tectonic movement time of the strike-slip prototype.

[0041] Polytetrafluoroethylene is filled as a sealing filler between the second enclosure 9 and the first enclosure 4, and between the movable enclosure 16 and the first enclosure 4. The shear block 19 is made of high-speed steel shear block to ensure that it is not easily damaged during the operation of the device. The sealing material between the enclosures is made of polytetrafluoroethylene, which has a low friction coefficient and is tightly matched with the enclosure to ensure sealing.

[0042] In the specific implementation, the device is made of rigid material aviation aluminum alloy 7075, which can meet the rigidity requirement of maintaining stability under high acceleration g value. The internal dimensions of the device are 800 mm×600 mm×200 mm, and the travel of the slidable drive unit is ±100 mm, which meets the slip displacement requirements of different test designs. The curved platform is composed of three curved platforms, and the cross-section of the curved platform is an arc surface. The joint action of the three curved platforms can provide a curved equipotential surface under the ultragravity centrifuge to ensure that the model material in the test device is in the same intensity of the ultragravity field. The curvature radius of the curved platform in this embodiment is 4380 mm, and it is made of SKD11 alloy steel.

[0043] The device of the present invention has two motion modes, where only one side of the drive unit 1 moves, or the two drive units 1 move together. The motion mode can be selected and adjusted according to the test requirements to simulate the evolution process of a single strike-slip fault at different rates, or to simulate the evolution process of two parallel faults at different strike-slip rates and different strike-slip forms, and explore the control effect of parallel strike-slip faults on the structural deformation field. The reducer 12 in the drive unit 1 drives the lead screw 17 to rotate through the coupling 14, and then converts the rotation into linear motion to drive the movable enclosure 16 forward. The ball screw 17 of the drive unit 1 is a rough lead screw, which can provide at least 400kN output, the travel speed can be controlled at 0-2mm / s, the overall stroke is at least 100mm, and the drive unit 1 can achieve a minimum speed accuracy control of 0.01mm / s. A high-speed steel shear block is provided at the connection between the second enclosure 9 / the movable enclosure 16 and the first enclosure 4, and is sealed by polytetrafluoroethylene material to prevent wear during the operation of the device and ensure sealing. The driving unit 1 of the device is connected to an external control system, which controls the speed of the motor 11 through the control system, thereby accurately controlling the moving speed of the movable enclosure 16. The control system can set the advancement distance, displacement rate and related test parameters of the movable enclosure 16 through the human-computer interaction interface, and the segmented advancement process can be set according to the test requirements during the test.

[0044] The embodiment of the present invention includes the following steps: Figure 6 As shown, Step S1, first, evenly lay the strike-slip model in the strike-slip chamber; Step S2: Next, the device is hoisted into a centrifuge as a whole to perform a centrifugal slip simulation test under a hypergravity environment; Step S3: In a centrifugal strike-slip simulation test, the strike-slip model in the strike-slip chamber is observed to obtain the deformation characteristics of the strike-slip model, thereby restoring the rupture law of the strike-slip fault under the action of tectonic deformation under real working conditions.

[0045] Specifically, the ductile material can be laid in the strike-slip chamber first, and then run for a period of time under a certain supergravity acceleration value until the ductile material is leveled. When the centrifuge stops running, the brittle material is quickly laid on the ductile material layer to complete the laying of the strike-slip model, and then the centrifugal strike-slip simulation test is started. Carry out multiple groups of centrifugal strike-slip simulation tests, and the monitoring system installed on the centrifuge monitors and records the test process in real time. The pictures, three-dimensional coordinates and other data of the model during the test are analyzed and processed to obtain regional displacement field and velocity field data, and the regional displacement field and velocity field data are compared and corrected with the historical displacement and velocity data monitored and recorded on site. At the same time, the internal section of the device is observed to realize the analysis of the internal structural deformation of the rock mass. The monitoring system includes a full-frame industrial camera and a three-dimensional optical scanner for real-time imaging of the model. After the test, the device and the monitoring system are disassembled, and the residual test materials in the device are cleaned.

[0046] The centrifugal slip simulation test under supergravity environment in step S2 is specifically as follows: First, the entire device is hoisted into the basket of the centrifuge and fixed, the centrifuge is started, the centrifugal acceleration of the centrifuge is gradually increased to a preset value Ng and maintained for a preset time, and the drive unit 1 is started through the control system under Ng hypergravity. The motor 11 in the drive unit 1 drives the screw 17 to rotate, thereby driving the second curved table 8 to move back and forth, so that the strike-slip model placed on the second curved table 8 will slip. During the centrifugal strike-slip simulation test, the displacement of the movable enclosure 16 / the second enclosure 9 is monitored in real time through the monitoring system connected to the centrifuge, and the deformation characteristics of the strike-slip model in the hypergravity environment are obtained.

[0047] In step S1, the material used in the strike-slip model is one of a brittle material, a ductile material, and a combination of a brittle material and a ductile material. The brittle material and the ductile material are selected as follows: If the strike-slip model uses brittle materials, the uniaxial compressive strength of the brittle materials is obtained according to the following formula: E m / E0=(ρ m / ρ0)×(l m / l0) ×(g m / g0) g m / g0=N Among them, E m is the uniaxial compressive strength of the strike-slip model material; ρ m is the density of the strike-slip model material; g m is the gravitational acceleration of the strike-slip model; l m is the size of the strike-slip model; E0 is the uniaxial compressive strength of the prototype material; ρ0 is the density of the prototype material; g0 is the gravitational acceleration of the strike-slip prototype; l0 is the actual size of the strike-slip prototype; N represents the ratio of the centrifugal acceleration of the model in the hypergravity environment to the normal gravitational acceleration of the prototype.

[0048] If the strike-slip model uses ductile material, the viscosity of the ductile material is obtained according to the following formula: η m / η0=(ρ m / ρ0)×(l m / l0) ×(g m / g0)×(t m / t0) g m / g0=N Among them, η m is the viscosity of the strike-slip model material; tm is the movement time of the strike-slip model; η0 is the viscosity of the prototype material; t0 is the tectonic movement time of the strike-slip prototype.

[0049] In the brittle material-ductile material combination, the ratio of the thickness of the brittle material to that of the ductile material is 1:1~1:5.

[0050] Brittle materials include quartz sand, gypsum, barite powder, etc., and tough materials include silicone, paraffin, plasticine, glycerin, etc.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A parallel strike-slip structural deformation supergravity test device, characterized in that: The invention comprises a driving unit (1), a first curved surface platform (3), a first enclosure (4) and a bottom plate (5); the two driving units (1) are respectively fixedly mounted on both sides of the bottom plate (5); the two driving units (1) are centrally symmetrically arranged with the center of the bottom plate (5) as the axis of symmetry; the first curved surface platform (3) is located between the two driving units (1); the first curved surface platform (3) is fixedly mounted in the middle of the bottom plate (5); the two first enclosures (4) are fixedly connected to both ends of the first curved surface platform (3); the two driving units (1) are respectively in contact with both sides of the first enclosure (4); the two driving units (1), the first curved surface platform (3) and the two first enclosures (4) form a strike-slip chamber for placing a strike-slip model; the driving unit (1) is used to drive the strike-slip model to slip.

2. The parallel strike-slip structural deformation supergravity test device according to claim 1, characterized in that: The driving unit (1) comprises a second curved surface platform (8), a second enclosure (9), a motor (11), a reducer (12), a movable enclosure (16) and a screw rod (17); The output shaft of the motor (11) is connected to one end of the output shaft of the reducer (12); the other end of the output shaft of the reducer (12) is connected to the screw (17) via a coupling (14); the two ends of the screw (17) are respectively mounted on a screw fixing side mounting seat (15) and a screw supporting side mounting seat (18); the screw fixing side mounting seat (15) and the screw supporting side mounting seat (18) are both fixedly connected to the bottom plate (5); the movable enclosure (16) is connected to the screw (17) so as to be movable forward and backward; the second curved table ( 8) is connected to the bottom plate (5) via a linear guide rail (7) so as to be movable forward and backward, the second enclosure (9) and the movable enclosure (16) are fixedly connected to the two ends of the second curved platform (8), and a baffle is connected between the second enclosure (9) and the movable enclosure (16), and the baffle is fixedly connected to the second curved platform (8), and the motor (11) is used to drive the screw rod (17) to rotate via the reducer (12), thereby realizing the forward and backward movement of the movable enclosure (16), the second enclosure (9) and the second curved platform (8) via the screw rod (17); The first curved platform (3) is movably connected between the second curved platforms (8) of the two drive units (1), and each first enclosure (4) is movably connected between the second enclosure (9) of one drive unit (1) and the movable enclosure (16) of another drive unit (1).

3. The parallel strike-slip structural deformation supergravity test device according to claim 2, characterized in that: A flange is provided at the bottom end of the second curved platform (8) on the side close to the first curved platform (3), and horizontal grooves matching the flange are provided on both sides of the bottom end of the first curved platform (3), and the flange of the second curved platform (8) is connected to the horizontal groove of the first curved platform (3) in a manner that it can move forward and backward.

4. The parallel strike-slip structural deformation supergravity test device according to claim 2, characterized in that: A vertical groove is provided at the rear end of the second enclosure (9) and the movable enclosure (16) close to the first enclosure (4), and a shear block is installed at the vertical groove. The second enclosure (9) and the movable enclosure (16) are sealed and connected to both sides of the first enclosure (4) so ​​as to be movable forward and backward.

5. The parallel strike-slip structural deformation supergravity test device according to claim 2, characterized in that: The first curved platform (3) and the two second curved platforms (8) located on both sides of the first curved platform (3) form a curved platform, the central axis of the curved platform coincides with the rotation axis of the centrifuge, and the curvature of the cross section of the curved platform is 4000-4500 mm.

6. The parallel strike-slip structural deformation supergravity test device according to claim 2, characterized in that: Polytetrafluoroethylene is filled as a sealing filler between the second enclosure (9) and the first enclosure (4), and between the movable enclosure (16) and the first enclosure (4).

7. A parallel strike-slip structural deformation supergravity test method applied to the device described in any one of claims 1 to 6, characterized in that: The following steps are involved: Step S1, first, evenly lay the strike-slip model material in the strike-slip chamber; Step S2: Next, the device is hoisted into a centrifuge as a whole to perform a centrifugal slip simulation test under a hypergravity environment; Step S3: observing the strike-slip model in the strike-slip chamber in the centrifugal strike-slip simulation test to obtain the deformation characteristics of the strike-slip model, and then restore the rupture law of the strike-slip fault under the action of tectonic deformation under real working conditions.

8. The method for parallel strike-slip structural deformation supergravity test according to claim 7, characterized in that: The centrifugal slip simulation test under the supergravity environment in step S2 is specifically as follows: First, the entire device is hoisted into the basket of a centrifuge and fixed, the centrifuge is started, the centrifugal acceleration of the centrifuge is gradually increased to a preset value Ng and maintained for a preset time, and the drive unit (1) is started through the control system under Ng hypergravity, the motor (11) in the drive unit (1) drives the screw (17) to rotate, and then drives the second curved table (8) to move forward and backward, so that the strike-slip model placed on the second curved table (8) strikes and slips. During the centrifugal strike-slip simulation test, the displacement of the movable enclosure (16) and the second enclosure (9) is monitored in real time through a monitoring system connected to the centrifuge to obtain the deformation rate of the strike-slip model, and at the same time, the surface deformation characteristics of the strike-slip model in a hypergravity environment are obtained.

9. The method for parallel strike-slip structural deformation supergravity test according to claim 7, characterized in that: In step S1, the material used in the strike-slip model is one of a brittle material, a ductile material, and a combination of a brittle material and a ductile material. The brittle material and the ductile material are selected as follows: The uniaxial compressive strength of brittle materials is obtained according to the following formula: E m / E0=(ρ m / ρ0)×(l m / l0)×(g m / g0) g m / g0=N Among them, E m is the uniaxial compressive strength of the strike-slip model material; ρ m is the density of the strike-slip model material; g m is the gravitational acceleration of the strike-slip model; l m is the size of the strike-slip model; E0 is the uniaxial compressive strength of the prototype material; ρ0 is the density of the prototype material; g0 is the gravitational acceleration of the strike-slip prototype; l0 is the actual size of the strike-slip prototype; N represents the ratio of the centrifugal acceleration of the model in the hypergravity environment to the normal gravitational acceleration of the prototype; The viscosity of the ductile material is obtained according to the following formula: or m / η0 =(ρ m / ρ0)×(l m / l0)×(g m / g0)×(t m / t0) g m / g0=N Among them, η m is the viscosity of the strike-slip model material; t m is the movement time of the strike-slip model; η0 is the viscosity of the prototype material; t0 is the tectonic movement time of the strike-slip prototype.

10. A parallel strike-slip structural deformation supergravity test method according to claim 9, characterized in that: In the brittle material-tough material combination, the thickness ratio of the brittle material to the tough material is 1:1 to 1:5.

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