Shear force distribution popularization device and design method thereof

Abstract

This invention discloses a shear force distribution science popularization device and its design method, including a base, a support mechanism, a loading mechanism, and a demonstration mechanism. The support mechanism includes a frame structure and a slide rail. The frame structure is connected to the base via bottom bolts, and the slide rail is connected to the frame structure via bolts on both sides. The loading mechanism includes a loading execution component, a transmission component, and a displacement control component. The loading execution component is connected to a base at its lower part. The displacement control component is connected to the loading execution component via the transmission component and is fixed to the frame structure via bolts. The demonstration mechanism includes multiple vertical columns with fixing components installed on the upper and lower sides. The upper fixing component is connected to the connecting base via bolts, and the lower fixing component is fixed to the base via bolts. This device follows the shear force distribution method principle, reproducing the shear force transmission law of rigid frames and other structures in actual engineering, providing an intuitive science popularization tool for practical application scenarios such as engineering reinforcement.

Description

Technical Field

[0001] This invention relates to the field of disaster prevention and reinforcement science popularization devices, specifically to an engineering science popularization device based on the shear force distribution method and its design method. Background Technology

[0002] The engineering field is currently facing a situation of increasing stock of old buildings and accelerated urban renewal. Structural reinforcement has become a core element in ensuring building safety and extending service life, with applications covering multiple fields such as residential renovation, public building transformation, and industrial plant upgrades. However, in the actual reinforcement process, there is a common misconception of "targeted reinforcement of weak parts," believing that continuously strengthening a single weak component can improve the overall structural safety, while ignoring the overall laws governing structural stress.

[0003] In terms of disaster prevention and safety awareness, building users also have obvious misconceptions. Most people intuitively believe that "the thicker the cross-section of a component and the higher its strength, the safer it is." When disasters such as earthquakes occur, they tend to take shelter next to seemingly sturdy thick columns and walls, but they do not know that structural stress follows the law of shear force distribution. Excessive reinforcement of a single component can disrupt the overall stiffness balance and cause shear force redistribution. This may turn the "reinforced strong component" into a weak point with concentrated stress, and it will be the first to fail in a disaster.

[0004] Shear force, as the core resistance of a structure against horizontal loads, directly determines the safety performance of a building under horizontal loads such as earthquakes and strong winds. The shear force distribution method, a core method in structural mechanics for analyzing the stress on structural members under horizontal loads, can accurately reveal the proportion of shear force borne by members of different stiffnesses. It is a key theoretical basis for avoiding reinforcement pitfalls and optimizing structural design. However, current popularization of shear force distribution methods in the engineering field relies heavily on abstract theoretical lectures, static drawings, or demonstrations of general structural models. There is a lack of dedicated popularization devices for real-world engineering scenarios. This makes it difficult for engineering technicians, construction workers, and building users to combine theory with practice, resulting in a lack of in-depth understanding of core logics such as "stiffness matching" and "shear force redistribution." This affects the scientific validity and safety of reinforcement schemes and also hinders the improvement of public disaster prevention and safety awareness.

[0005] Therefore, developing a specialized science popularization device that can intuitively present the shear force distribution law and correct the misconceptions about reinforcement is of great practical significance. Summary of the Invention

[0006] The purpose of this invention is to provide a shear force distribution popular science device and its design method to solve the key problems raised in the background art: with the increasing stock of old buildings and the accelerated pace of urban renewal, structural reinforcement scenarios are becoming increasingly widespread. However, there is a common misconception in the engineering field regarding "targeted reinforcement of weak parts," and building users also have a misconception that "the thicker the component cross-section, the safer it is for disaster prevention." Existing popular science methods for shear force distribution rely on abstract theories, static drawings, or general models, lacking specialized devices that fit actual engineering scenarios. They cannot simulate the differences in shear force transmission between rigid frames and truss frames, nor can they intuitively present the importance of stiffness matching during the reinforcement process. This leads to a lack of in-depth understanding among engineering technicians, construction workers, and building users of core logics such as "blind reinforcement easily leads to risks" and "stiffness imbalance leads to shear force redistribution," resulting in a disconnect from actual engineering applications and the public's disaster prevention and safety needs.

[0007] To achieve the above objectives, this invention provides a shear force distribution science popularization device with the following technical solution: A shear force distribution science popularization device and its design method, comprising a base, a support mechanism, a loading mechanism, and a demonstration mechanism. The base is a rigid load-bearing structure. The support mechanism is a frame structure with slide rails, fixedly connected to the base by bolts. The loading mechanism includes: a displacement control component, a loading execution component, and a transmission assembly. The displacement control component and the loading execution component are connected to the support mechanism by bolts, and the displacement control component and the loading execution component are connected by the transmission assembly. The loading execution component is fixedly connected to the connecting base. The demonstration mechanism includes multiple vertical columns arranged at intervals along the loading direction. Fixing components are installed at the top and bottom of the vertical columns, which are fixedly connected to the base by bottom fixing components. The vertical columns are connected to the connecting base by top fixing components.

[0008] Preferably, the base is a steel plate with several mounting holes for matching bolts. The mounting holes allow for fixed connection with the support mechanism and the demonstration mechanism using bolts.

[0009] Preferably, the frame structure of the support mechanism is a portal frame. The bottom of the portal frame is fixedly connected to the mounting holes of the base by bolts. The side columns of the portal frame are reserved with connection positions for mounting vertical slide rails. The vertical slide rails are fixed to the side columns of the portal frame by bolts. The two ends of the horizontal slide rails are fixedly connected to the horizontal and vertical slide rail connectors by bolts. One side of the horizontal and vertical slide rail connectors is provided with a vertical groove, which is adapted to the side protrusion of the vertical slide rail to form a sliding fit.

[0010] Preferably, the displacement control component includes a pulley base, a pulley shaft, a pin, a transmission pulley, a sleeve, and a displacement control rocker arm; pulley bases are fixed on the left and right sides of the portal frame, and the pulley bases have coaxial shaft holes and pin holes. The pulley shaft passes through the shaft hole to form a coaxial fit, and the pin passes through the pin hole with its end fitting to the outer circumferential surface of the pulley shaft; the transmission pulley is sleeved in the middle of the pulley shaft and coaxially fits the pulley shaft; two sleeves are provided and are respectively sleeved on the pulley shaft at positions on both sides of the transmission pulley; one end of the pulley shaft is fixedly connected to the displacement control rocker arm by bolts.

[0011] Preferably, the loading execution component is a rigid transverse loading plate; the bottom of the rigid transverse loading plate is provided with a connecting base; the bottom of the rigid transverse loading plate is provided with a groove extending along the length direction, which is adapted to the top protrusion of the horizontal slide rail to form a sliding fit.

[0012] Preferably, the transmission assembly includes a wire connecting plate, a wire, and a transmission pulley; the two sides of the transverse loading plate have pre-set connection slots, and the transverse loading plate is fixedly connected to the wire connecting plate by bolts; the wire connecting plate has a wire connecting hole, one end of the wire passes through the connecting hole and is fixed to the wire connecting plate, and the other end of the wire wraps around the rim of the transmission pulley and forms a mating connection with the transmission pulley.

[0013] Preferably, the demonstration mechanism includes multiple vertical columns and sleeves; sleeves are connected to both the upper and lower sides of the vertical columns, and the connection method between the sleeves and the vertical columns is selectable; the first connection method is that the sleeves are fixedly connected to the vertical columns, in which case the upper part of the sleeves is fixedly connected to the connecting base of the horizontal loading plate by bolts; the second connection method is that the sleeves are hinged to the vertical columns, in which case the upper part of the sleeves is rotatably connected to the lower hinge support of the horizontal loading plate by bolts.

[0014] Furthermore, the method specifically includes the following steps: S1. Determine the information of the vertical column to be designed, including the failure displacement d of different vertical columns, the gravity Fn of the load-bearing component of the vertical column, the height l of the vertical column, the cross-sectional shape of the vertical column, and the connection form of the top fastener (4-2) of the vertical column; S2. Design the stiffness ratio ω of the vertical column, and design the material and cross-sectional height of the vertical column accordingly; S3. Verify the compressive bearing capacity and buckling ultimate bearing capacity of the vertical column. If either of them is less than Fn, return to S1. S4. Based on the maximum load-bearing capacity of the vertical column, design the dimensions of the top fixing component (4-2) connector and the bottom fixing component (4-3) connector of the vertical column; S5. Based on the total shear force borne by the vertical column, design the loading method and counterweight of the loading execution component (3-2).

[0015] Furthermore, ω The formula derivation is as follows: For a symmetrical cross-section member, according to mechanics of materials, the bending moment that the cross-section can withstand under the ultimate bearing capacity is... M 1 is: (2) Meanwhile, for vertical columns, the maximum bending moment is generated under the condition of only tangential support displacement. M The formula for calculating 2 is: (3) In the formula: k The maximum bending moment coefficient is 6 when the sleeve is fixed to the vertical column and 3 when the sleeve is hinged to the vertical column. l This refers to the height of the vertical column; d The displacement at the support is [value missing]. When the vertical column is displaced at the support, [value missing]. d When damage occurs, the following occurs: (4) Combining (2), (3), and (4), the relationship between the dimensions of the vertical column and the material parameters should satisfy: (5) In this design, different vertical columns are all of the same height, the sleeves are connected to the vertical columns in the same way, and the same maximum bending moment coefficient is used. Therefore, the ratio between the failure displacements of the vertical columns is: (6) In the formula i , j Number the vertical columns.

[0016] Compared with existing technologies, the beneficial effects of this invention are: the shear force distribution science popularization device accurately adapts to the science popularization needs of structural reinforcement in the context of urban renewal, and addresses the operational misconception of "blind reinforcement" in engineering and the public's cognitive bias in disaster prevention. Through structural design, it achieves a deep integration of science popularization with actual scenarios. The specific advantages are as follows: (1) Adjustable structural parameters to fit diverse reinforcement scenarios: The device adopts a steel plate base with pre-set installation holes and a portal frame support mechanism. The installation position of the portal frame and the height of the horizontal slide rail can be flexibly adjusted through bolt connection, breaking through the limitations of traditional models that are "fixed in size and cannot be adapted to actual projects". The steel plate base ensures the stability of the device with its own rigidity, and the portal frame provides stable loading support. It can simulate building structures with different spans and heights, accurately restore the stress foundation of various reinforcement scenarios such as renovation of old houses and transformation of public buildings, and solve the problem of the disconnect between traditional models and actual engineering. (2) Strong hands-on interactivity, enhancing understanding of core logic: Equipped with a loading system consisting of displacement control components and transmission components, the transverse loading plate can be moved smoothly by rotating the displacement control rocker, and the pin design enables precise start and stop of the loading process. Relevant personnel can independently complete the loading operation, intuitively feel the relationship between load application and shear force transmission, replacing the traditional "one-way explanation and abstract understanding" popular science model, especially suitable for the step-by-step decomposition needs of stiffness adjustment and shear force redistribution in engineering training, helping construction and technical personnel to quickly master the core logic; (3) Precise load transfer avoids cognitive misguidance: A rigid transverse loading plate is used as the loading execution component. Through the sliding cooperation between the bottom groove and the horizontal slide rail, combined with the adaptive angle adjustment of the hinge support, the horizontal force is ensured to be evenly transferred to each vertical column, avoiding demonstration errors caused by loading offset or component deformation. This design ensures the accuracy of the shear force distribution law presentation, prevents relevant personnel from misunderstanding the force logic in actual engineering due to demonstration deviations, and helps to establish a correct understanding of "load transfer and structural force matching". (4) Comprehensive scenario coverage, directly addressing common misconceptions about reinforcement and disaster prevention: The demonstration facility supports both fixed and hinged connections between sleeves and vertical columns, covering the popular science needs of core engineering structural frames and truss forms. Through combinations of vertical columns with different cross-sectional dimensions and materials, the rule that "the greater the stiffness, the more shear force it bears" can be intuitively presented, clearly restoring the engineering misconception that "blindly reinforcing weak components leads to a sudden increase in stiffness, which in turn causes the first failure." At the same time, it specifically corrects the disaster prevention cognitive bias that "the thicker the cross-section, the safer it is," enabling building users to understand the core logic of structural safety in disasters, and taking into account both engineering technology training and the improvement of public disaster prevention literacy. Attached Figure Description

[0017] Figure 1 is a schematic diagram of the overall structure of the present invention; Figure 2 is a partial schematic diagram of the connection between the horizontal loading plate and the vertical column; Figure 3 is a schematic diagram of the connection between the transmission pulley and the displacement control rocker. Figure 4 is a flowchart of the design method of the present invention; Figure 5 shows an example of the top fastener connection; Figure 6 shows an example of bottom fastener connection; Figure 7 shows the numerical model diagram; Figure 8 shows the numerical simulation results for the unreinforced system; Figure 9 shows the force-displacement curves in the unreinforced numerical simulation. Figure 10 shows the force-displacement curves after reinforcement, as simulated numerically.

[0018] Explanation of reference numerals in the attached drawings: 1. Base plate; 2-1. Portal frame; 2-2. Vertical slide rail; 2-3. Horizontal slide rail; 2-4. Horizontal and vertical slide rail connector; 3-1.1. Pulley base; 3-1.2. Pulley shaft; 3-1.3. Pin; 3-1.4. Sleeve; 3-1.5. Transmission pulley; 3-1.6. Displacement control rocker arm; 3-2. Horizontal loading plate; 3-2.1. Connecting base; 3-3.1. Steel wire connecting plate; 3-3.2. Steel wire; 4-1. Vertical column; 4-2. Fixing component. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without innovative labor are within the scope of protection of the present invention.

[0020] Please refer to the appendix. Figure 1-3 This invention provides a shear force distribution popular science device, including a base plate 1, a portal frame 2-1, a transverse loading plate 3-2, a vertical column 4-1, a transmission pulley 3-1.5, and a displacement control rocker 3-1.6. The base plate 1 and the portal frame 2-1 are connected by bolts, which ensures the overall structural stability of the device and prevents shaking during loading. The design of the portal frame 2-1 further enhances the overall load-bearing capacity and prevents frame deformation due to excessive load. The vertical column 4-1 is fixed to the base plate 1 by a bottom fixing member 4-3, which ensures the stability of the bottom position of the vertical column and prevents displacement under force. At the same time, it is connected to the connecting base 3-2.1 by a top fixing member 4-2. When the top fixing member 4-2 and the connecting base 3-2.1 are fixedly connected, the shear force distribution method of the rigid frame can be demonstrated. The top fixing member 4-2 and the connecting base 3-2.1 are detachable structures. By replacing them, the top fixing member 4-2 and the connecting base 3-2.1 can be rotatably connected, which can demonstrate the shear force distribution method of the frame.

[0021] When the top fixing part 4-2 is rotatably connected to the connecting base 3-2.1, the bottom connecting base 3-2.1 is designed as a hinge support. The two upper hinge supports are fixedly connected to the transverse loading plate 3-2 by bolts. The two upper hinge supports are hinged to the lower hinge support. This hinge structure can effectively limit the transmission of bending moment and achieve precise transmission of shear force, ensuring that the vertical column only bears shear force during the demonstration. The horizontal loading plate 3-2 is grooved and fits into the horizontal slide rail 2-3. This fit guides the horizontal loading plate 3-2 to slide stably in the horizontal direction, achieving precise control of the horizontal sliding displacement and avoiding lateral deviation during loading. The horizontal slide rail 2-3 is bolted to the horizontal-vertical slide rail connector 2-4, which fits into the vertical slide rail 2-2 through a groove. This structure allows the horizontal slide rail 2-3 to move vertically, achieving the vertical sliding displacement of the horizontal loading plate 3-2. This facilitates adjusting the loading position according to the height of the vertical column and adapts to the demonstration needs of vertical columns of different sizes. The vertical slide rail 2-2 is bolted to the portal frame 2-1, providing stable support for the slide rail and ensuring structural reliability during displacement adjustment.

[0022] A steel wire connecting plate 3-3.1 is fixed on the transverse loading plate 3-2. The steel wire connecting plate 3-3.1 is connected to the transmission pulley 3-1.5 through the steel wire 3-3.2. By rotating the transmission pulley 3-1.5 to tighten and pull the steel wire 3-3.2, the rotational motion of the pulley can be converted into the horizontal linear motion of the transverse loading plate 3-2, realizing the smooth driving of the horizontal displacement of the transverse loading plate 3-2, avoiding the sudden change of shear force caused by excessive loading speed, ensuring the accuracy of the demonstration data, and restoring the actual scenario of slow load application in engineering.

[0023] The portal frame 2-1 is fixed with pulley bases 3-1.1 on both the left and right sides, providing stable mounting support for the pulley shaft. A pulley shaft 3-1.2 is coaxially fitted onto the pulley base 3-1.1, allowing free rotation and providing a flexible rotation node for the transmission pulley. The pulley shaft 3-1.2 and the transmission pulley 3-1.5 are coaxially fitted and rotate synchronously through a groove fit, ensuring that the operating force of the displacement control rocker is accurately transmitted to the transmission pulley and preventing slippage. Sleeves 3-1.4 are coaxially fitted onto the pulley shaft 3-1.2 on both sides of the transmission pulley 3-1.5 to limit the axial position of the transmission pulley 3-1.5 and prevent the transmission pulley from slipping along the axis during rotation. Axial offset ensures the steel wire remains within the pulley groove. The pulley shaft 3-1.2 is connected to the displacement control rocker arm 3-1.6 via bolts. By rocking the displacement control rocker arm, the pulley shaft can be easily driven to rotate, achieving labor-saving operation. Simultaneously, a pin 3-1.3 is coaxially fitted on the pulley base 3-1.1. The pin 3-1.3 can be inserted and removed. When the pin 3-1.3 is removed, the rotation of the pulley shaft 3-1.2 can be achieved by rocking the displacement control rocker arm 3-1.6, facilitating loading operations. When inserted, it can lock the pulley shaft, achieving immediate fixation of the transmission pulley. This allows for pausing the demonstration at a specific displacement position to explain the shear force distribution under the current state, especially highlighting the key logic of "stiffness adjustment leading to shear force redistribution" in engineering reinforcement.

[0024] Working Principle: First, based on the needs of engineering popularization, vertical columns 4-1 with different cross-sectional dimensions, materials, or elastic coefficients are selected and securely installed on the foundation plate 1 using the bottom fixing component 4-3. The top fixing component 4-2 is then precisely connected to the connecting base 3-2.1 to complete the assembly of multi-stiffness vertical columns. A combination of "sudden increase in stiffness after reinforcement of the original weak vertical column" can be intentionally set to simulate common reinforcement scenarios in engineering, restoring the actual state of collaborative work between components of different stiffness. Subsequently, the pin 3-1.3 is inserted into the positioning hole of the pulley base 3-1.1. At this time, the pin will lock the pulley shaft 3-1.2, restricting the rotation of the transmission pulley 3-1.5, ensuring that the transverse loading plate 3-2 is stationary before loading, preventing initial position displacement due to accidental sliding. Finally, a weight of sufficient quantity is connected to the steel wire 3-3.2 via a hook, and the steel wire is fixed to the transverse loading plate 3-2 using the steel wire connecting plate 3-3.1. The weight of the object provides a stable and quantifiable tension to the steel wire, pre-storing the driving force required for loading and avoiding loading interruption due to insufficient tension during loading, which conforms to the actual situation of stable load application in engineering.

[0025] In the loading demonstration, the pin 3-1.3 on the pulley base 3-1.1 is first removed, releasing the restriction on the pulley shaft 3-1.2. Then, the displacement control rocker 3-1.6 is turned counterclockwise, causing the pulley shaft 3-1.2 to rotate synchronously. The transmission pulley 3-1.5, coaxial with the pulley shaft, rotates accordingly. Under the action of the groove, the transmission pulley tightens the steel wire 3-3.2, converting the rotational motion into a lateral pulling force, which pulls the transverse loading plate 3-2 horizontally to the right along the horizontal slide rail 2-3. Since the transverse loading plate 3-2 is connected to the lower hinge support 12 via the upper hinge support 13, the displacement is synchronously transmitted to all vertical columns 4-1, achieving synchronous horizontal displacement of multiple vertical columns. This aligns with the core premise of "equal horizontal displacement" in the shear force distribution method, restoring the basic characteristics of the overall stress distribution of the engineering structure.

[0026] During loading, if the vertical column 4-1 bends due to horizontal displacement, causing a change in its top height, the horizontal loading plate 3-2 will slide vertically synchronously along the vertical slide rail 2-2 via the horizontal-vertical slide rail connector 2-4, maintaining a tight connection with the top of the vertical column to prevent interruption of the loading force or the generation of additional bending moments due to height differences. Simultaneously, according to the popular science rhythm, the pin 3-1.3 can be reinserted at any displacement node to fix the transmission pulley 3-1.5 by locking the pulley shaft 3-1.2, achieving the gradual application of load. This can be paused to guide relevant personnel to observe the deformation degree of each vertical column under the current displacement, especially the deformation difference between the "vertical column with a sudden increase in stiffness after reinforcement" and other vertical columns. Combined with theoretical formulas, the shear force distribution coefficient can be calculated to strengthen the understanding of the correlation between "stiffness adjustment and shear force redistribution," and to emphasize the importance of avoiding blindly reinforcing single components in engineering reinforcement.

[0027] As the loading displacement continues to increase, the less stiff vertical column 4-1 will reach its ultimate bearing capacity and fail first. If there is a "vertical column with a sudden increase in stiffness after reinforcement," it will bear more shear force and may fail before the original stronger vertical column in subsequent loading, intuitively demonstrating the engineering misconception that "blindly reinforcing weak parts can easily lead to failure." Since each vertical column 4-1 is connected by an independent bottom fixing member 4-3 and connecting base 3-2.1, and the transverse loading plate 3-2 only transmits shear force, the failure of one vertical column will not interfere with the stress state of other undamaged vertical columns. The remaining vertical columns will continue to bear the load and gradually bear the force as the displacement increases until all reach their ultimate state. This process can intuitively demonstrate the mechanical law that "the greater the strength-stiffness ratio, the later the failure," and at the same time, it reflects the risk caused by stiffness mismatch in engineering reinforcement, helping relevant personnel understand the core principle of "stiffness balance matching" in structural disaster-resistant design and reinforcement optimization. The content not described in detail in this specification belongs to the prior art known to those skilled in the art.

[0028] Reference Figure 4 The flowchart shown illustrates the specific steps of implementing this invention as follows: 1. Determine the information of the vertical column 4-1 to be designed, including the failure displacement d of different vertical columns 4-1, the gravity Fn of the loading execution component supported by the vertical column, the height l of the vertical column, the cross-sectional shape of the vertical column, and the connection form of the top fixing member 4-2 of the vertical column. In this embodiment, the connection form of the top fixing member 4-2 of the vertical column is hinged, the failure displacement is set to 2mm, 4mm, and 6mm respectively, and the height of the vertical column is set to 30cm.

[0029] 2. Design the stiffness ratio of the vertical columns ω Based on this, the material and cross-sectional height of the vertical columns were designed.

[0030] In this embodiment, the stiffness ratio of the vertical columns is set to 1:2:3, and the cross-sectional shape of the vertical columns is selected as a rectangle with a uniform cross-sectional width. The height of the vertical column cross-section is calculated using the following formula: (7) Where: the maximum bending moment coefficient is 3 when the connection between the top fixing part 4-2 and the loading execution part 3-2 is hinged, and 6 when the connection between the top fixing part 4-2 and the loading execution part 3-2 is fixed.

[0031] 3. Verify the compressive bearing capacity and buckling ultimate bearing capacity of vertical column 4-1. If either is less than... F n If so, return to step 1. According to the "Steel Structure Design Standard" GB 50017-2017, the verification formulas are as follows: (8) (9) In the formula: f n The compressive strength of the material; A The cross-sectional area of ​​the vertical column; μ The length factor for calculating the critical buckling load is taken as 0.7 here because the connection between the top fixing member 4-2 and the loading actuator 3-2 is hinged, the shear force borne by the connection is greater than the maximum shear force borne by the vertical column, and the connection does not bear bending moment; when the connection between the top fixing member 4-2 and the loading actuator 3-2 is fixed, μ The value is 0.5, the shear force of the connection is greater than the maximum shear force of the vertical column, and the bending moment of the connection is greater than the maximum bending moment of the vertical column; π is the mathematical constant pi. I Let be the moment of inertia of the vertical column section as it rotates along the loading direction.

[0032] 4. Based on the maximum load-bearing capacity of the vertical column 4-1, design the dimensions of the top fixing member 4-2 and the bottom fixing member 4-3. In this embodiment, the top fixing member 4-2 connector is as follows: Figure 5 As shown, the bottom fixing part 4-3 connector is as follows Figure 6As shown, design the materials and dimensions of bolts 1, 2, and 3. According to the steel structure design standard GB 50017-2017, the design formula for bolt 1 is as follows: (10) In the formula: f v1 b It is the shear strength of bolt 1; d b1 This refers to the diameter of bolt 1. The design formula for bolt 2 is as follows: (11) (12) (13) (14) (15) In the formula: N v2 This refers to the shear force borne by each bolt 2; N v2 b This is the shear bearing capacity of each bolt 2; N t2 It is the tensile force borne by bolt 2 on the tension side; N t2 b This is the tensile bearing capacity of each bolt 2; k q It is the shear force coefficient. When the connection method of its top fastener 4-2 is a fixed connection, it is taken as 12, and when the connection method of its top fastener 4-2 is a rotatable connection, it is taken as 3. d b2 It is the diameter of bolt 2; f v2 b It is the shear strength of bolt 2; k m It is the bending moment coefficient. It is 6 when the connection method of its top fastener 4-2 is a fixed connection, and 3 when the connection method of its top fastener 4-2 is a rotatable connection. h 2 It is half the horizontal distance between the centers of the two bolts 2; f t2 b This refers to the tensile strength of bolt 2. The design formula for bolt 3 is as follows: (16) In the formula: d b3 It is a bolt with a diameter of 3. f v3 bIt is the shear strength of bolt 3.

[0033] 6. Determine the maximum force required to be applied to the transverse loading plate 3-2. F T The calculation method is the sum of the maximum shear force that all vertical columns 4-1 can withstand, and the formula is as follows: (17) In the formula: k q This is the maximum shear force coefficient of the vertical column, taken as 3; d i It is the first i The failure displacement of the vertical column; E i It is the first i The elastic modulus of the vertical column; I i It is the first i The moment of inertia of the vertical column section rotating along the loading direction; l i It is the first i The length of the vertical column; n This represents the total number of vertical columns.

[0034] 7. Determine the loading method and counterweight for loading execution component 3-2. Design a suitable loading method and counterweight to enable it to apply... F T This ensures the stability of displacement control.

[0035] Numerical simulations were performed for the above operating conditions.

[0036] This embodiment comprises two parts: The first part involves the vertical columns failing at displacements of 4mm, 10mm, and 16mm, representing coarse, thin, and medium thicknesses, respectively. All columns are 30cm high and are solid cylindrical. The top fastener 4-2 is a hinged connection, and the strength-to-stiffness ratio is set to 2:5:8 based on the failure displacement, demonstrating the shear force distribution principle of the frame columns. The second part reinforces the vertical column that failed at 16mm in the first part by replacing its cross-section with a higher-strength, higher-stiffness material and increasing its diameter, thus altering the failure sequence and demonstrating the reinforcement principle.

[0037] This embodiment uses OpenSees for simulation. The simulation model is built according to the actual loading conditions, such as... Figure 7 The `equaldof` command was used to simulate a horizontally loaded plate, causing the vertical columns to undergo the same horizontal displacement. The `Concrete06` constitutive model was used to simulate brittle materials. The displacement was applied in 2000 steps using the `integrator` command, slowly loading to 0.02 mm to simulate actual loading conditions.

[0038] Figure 8The material and dimensional parameters of each vertical column in this embodiment are shown. Figure 9 The force-displacement curves from finite element simulations based on these parameters are shown, along with the column states at each stage. Results show that the simulation based on the column material and dimensions designed using formula (2) yields a failure displacement almost equal to the designed failure displacement. Furthermore, the peak shear force calculated for each column using formula (12) is very close to the peak shear force obtained from the simulation. This design method effectively calculates the failure displacement and failure shear force of brittle material columns, providing a reliable theoretical basis for demonstrating the device's principle. Simultaneously, due to material differences, column failure does not follow a sequence from coarse to fine; instead, it exhibits a failure sequence of coarse → fine → medium. This demonstrates the objective law that thick columns are not necessarily safe in building structures.

[0039] right Figure 9 The column that ultimately failed was reinforced by replacing the original material with one having a tensile strength of 800 MPa and an elastic modulus of 400 GPa, and increasing the cross-sectional diameter to 12.6 mm. The force-displacement curves and the column's state at each stage are shown below. Figure 10 It was found that although the reinforced vertical column could withstand significantly increased shear force, the displacement at failure was less than that of the reinforced column. Figure 9 The second column that failed experienced a small displacement, demonstrating the actual situation where a project reinforced with high-strength, high-rigidity materials failed first under earthquake conditions.

[0040] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A shear force distribution science popularization device, comprising a base, a support mechanism, a loading mechanism, and a demonstration mechanism, characterized in that: The base (1) is a rigid load-bearing structure; the support mechanism (2) is a frame structure (2-1) with a slide rail, which is fixedly connected to the base (1) by bolts; the loading mechanism (3) includes: a displacement control component (3-1), a loading execution component (3-2) and a transmission component (3-3). The displacement control component (3-1) and the loading execution component (3-2) are connected to the support mechanism (2) by bolts. The displacement control component (3-1) and the loading execution component (3-2) are connected by the transmission component (3-3). The loading execution component (3-2) is fixedly connected to the connecting base (3-4); the demonstration mechanism (4) includes multiple vertical columns (4-1) arranged at intervals along the loading direction. The vertical columns (4-1) are fixed with fixing parts (4-2) installed on the top and bottom. The vertical columns (4-1) are fixedly connected to the base (1) by the bottom fixing part (4-3). The vertical columns (4-1) are connected to the connecting base (3-4) by the top fixing part (4-2).

2. The cop of claim 1, wherein: The frame structure (2-1) has preset installation positions on both sides. The vertical slide rail (2-2) is fixedly connected to the frame structure (2-1) by bolts. The horizontal slide rail (2-3) has a mating structure extending along the length direction on both sides. The mating structure forms a sliding fit with the vertical slide rail (2-2).

3. The coplanar device of claim 1, wherein: The frame structure (2-1) has preset base mounting positions on its left and right sides respectively. The displacement control component base (3-1.2) is fixedly connected to the base mounting position of the frame structure (2-1) by bottom bolts. The displacement control component base (3-1.2) is coaxially fitted with a loading shaft (3-1.3) and a displacement limiting device (3-1.4). The loading shaft (3-1.3) is connected to the displacement control rocker (3-1.6) by bolts.

4. The shear force distribution science popularization device according to claim 1, characterized in that: The loading execution component (3-2) is provided with an upper preset mounting position, which is movably connected to the displacement control component (3-1) through the transmission component (3-3); the loading execution component (3-2) is provided with a lower preset mounting position, and the connecting base (3-2.1) is fixedly connected to the loading execution component (3-2) by bolts; the loading execution component (3-2) is provided with a mating structure extending along the length direction on both sides, which forms a sliding fit with the horizontal slide rail (2-3); the vertical column (4-1) is hinged or fixedly connected to the connecting base (3-2.1) through the top fixing part (4-2).

5. A design method for an engineering science popularization device based on shear force distribution, characterized in that: Design vertical columns with different strength-stiffness ratios ω, and design fastener connections sufficient to withstand the load-bearing capacity of the vertical columns.

6. A method of designing a popular science device for shear distribution method according to claim 5, wherein, The formula for the strength-to-stiffness ratio ω is: (1) wherein: f is the flexural strength of the column material; E is the elastic modulus of the column material; h is the height of the column cross-section in the loading direction; ω the smaller, the more the column will fail; the column failure displacement and ω are directly proportional to the ratio.

7. A method of designing a shear distribution method for a cop according to claim 5, wherein The method specifically includes the following steps: S1. Determine the information of the vertical column to be designed, including the failure displacement d of different vertical columns, the gravity Fn of the load-bearing component of the vertical column, the height l of the vertical column, the cross-sectional shape of the vertical column, and the connection form of the top fastener (4-2) of the vertical column; S2. Design the stiffness ratio of the vertical column, and design the material and cross-sectional height of the vertical column accordingly; S3. Verify the compressive bearing capacity and buckling ultimate bearing capacity of the vertical column. If the requirements are not met, return to S1. S4. Based on the maximum load-bearing capacity of the vertical column, design the dimensions of the top fixing component (4-2) connector and the bottom fixing component (4-3) connector of the vertical column; S5. Based on the total shear force borne by the vertical column, design the loading method and counterweight of the loading execution component (3-2).

8. The steps of claim 7, wherein: By precisely designing the columnar structure parameters, stiffness ratio, and connectors, it is possible to achieve the destruction of three columnar structures of different thicknesses in a pre-set order, and the destruction order can be freely adjusted according to the needs of popular science education.

9. The method of claim 5, wherein: The vertical load and the bearing capacity of the connecting parts need to be verified. The compressive bearing capacity and buckling ultimate bearing capacity of the vertical column are both greater than the vertical load transmitted by the loading actuator (3-2). F n The connection between the bottom fixing part (4-3) and the base (1) can withstand the maximum load borne by the vertical column; the force that the loading execution part can apply is greater than the total shear force borne by the vertical column; the verification formula is in accordance with the "Steel Structure Design Standard" GB 50017-2017.

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