A method and device for simulating unidirectional uniformly distributed load loading on a simply supported beam

Abstract

The present invention discloses a method and device for simulating the unidirectional uniformly distributed load of a simply supported beam, comprising: obtaining the maximum theoretical deflection of the simply supported beam specimen to be tested before the simulation test; determining the minimum stiffness of the spring and the stiffness distribution coefficient of the springs distributed along the rigid distribution beam based on the maximum theoretical deflection of the simply supported beam specimen; arranging a plurality of springs at the bottom of the rigid distribution beam according to the stiffness distribution coefficient of the springs along the rigid distribution beam, thereby forming a spring distribution beam for simulating the uniformly distributed load; and placing the spring distribution beam on the simply supported beam specimen during the simulation test, with the springs contacting the simply supported beam specimen and applying a concentrated load to the rigid distribution beam of the spring distribution beam. The spring distribution beam converts the concentrated load into a uniformly distributed load, and applies the uniformly distributed load to the simply supported beam specimen via the springs. The present invention uses the designed spring distribution beam to evenly distribute the load provided by the servo hydraulic jack to the tested beam specimen, thereby completing the loading simulation of the uniformly distributed load on the simply supported beam.

Description

Technical Field

[0001] The present invention relates to the technical field of civil engineering structure testing, and in particular to a method and device for simulating the loading of a simply supported beam with a unidirectional uniformly distributed load. Background Art

[0002] In civil engineering structures, simply supported beams are a common structural component, and the uniformly distributed load acting on simply supported beams is also a relatively common form of load.

[0003] At present, the loading simulation test of uniformly distributed load on simply supported beams is mainly carried out through the stacking method, that is, the counterweight blocks are placed on the simply supported beam specimen to achieve the load loading. Due to the limitations of the test conditions, it is usually difficult to accurately control and simulate the uniformly distributed load using this stacking method, especially when the load to be simulated is relatively large, the stacking method basically cannot achieve the target load loading. In addition, during the loading process, if the simply supported beam specimen to be tested is deformed, it will cause the stacking blocks stacked on the simply supported beam specimen to come into contact and collide, changing the load form, thereby affecting the test results. In more serious cases, it may even cause the stacking blocks to fall, resulting in a safety accident.

[0004] This shows that the control problem and load form problem of the loading method during the test are both uncontrollable factors, which not only cannot accurately simulate the target uniformly distributed load, but also poses a major safety hazard during the test. Summary of the Invention

[0005] To this end, the technical problem to be solved by the present invention is to overcome the defects in the existing technology, and aims to improve the load form and uncontrollable problems in loading control that occur in the stacking technology. A unidirectional uniformly distributed load simulation device for a simply supported beam is designed. During the test, the load size is controlled by a servo hydraulic jack, and the load state is monitored by a force sensor. Finally, the load provided by the servo hydraulic jack is evenly distributed to the tested beam specimen through the designed spring rigidity distribution beam to complete the simulation of the uniformly distributed load on the beam.

[0006] To solve the above technical problems, the present invention provides a method for simulating the loading of a simply supported beam with a unidirectional uniformly distributed load, comprising:

[0007] Before the simulation test, obtaining the maximum theoretical deflection of the simply supported beam specimen to be tested;

[0008] Determining the minimum stiffness of the spring and the stiffness distribution coefficient of the springs distributed along the stiffness distribution beam according to the maximum theoretical deflection of the simply supported beam specimen;

[0009] According to the stiffness distribution coefficient of the springs along the rigid distribution beam, a plurality of the springs are arranged at the bottom of the rigid distribution beam according to the stiffness distribution coefficient to form a spring distribution beam for simulating uniformly distributed load;

[0010] Among them, the minimum stiffness of the spring is

[0011]

[0012] Where E is the elastic modulus of the beam, I is the section moment of inertia of the beam, l is the span of the beam specimen, and δ max is the relative displacement coefficient at the maximum position along the span direction of the simply supported beam specimen;

[0013] The stiffness distribution coefficient of the springs distributed along the rigid distribution beam is

[0014]

[0015] Where k i is the spring stiffness required at different positions, k min is the minimum stiffness of the spring, δ i is the relative displacement coefficient at different positions along the span of the beam.

[0016] As a preferred embodiment of the present invention, the step of obtaining the maximum theoretical deflection of the simply supported beam specimen includes:

[0017] According to the span of the simply supported beam specimen and the size of the uniformly distributed load, the bending moment distribution of the simply supported beam specimen under the uniformly distributed load is obtained;

[0018] A deflection curve formula is obtained based on the bending moment distribution;

[0019] The parameters of different positions of the simply supported beam specimen are brought into the deflection curve formula to obtain the theoretical deflection coefficient χ at different positions along the span direction of the simply supported beam specimen. i , see Table 1,

[0020] Table 1. Deflection coefficient χ under uniformly distributed load i

[0021]

[0022] As a preferred embodiment of the present invention, the step of determining the minimum stiffness of the spring includes:

[0023] According to the uniformly distributed load and the theoretical deflection coefficient, the deflection formula of the simply supported beam specimen under the uniformly distributed load is obtained;

[0024] According to the deflection formula of the simply supported beam specimen under uniformly distributed load and Hooke's law, the spring stiffness k required at different positions of the simply supported beam specimen is obtained. i ,

[0025]

[0026] Where, δ iis the relative displacement coefficient at different positions along the span of the beam, i is 0, 1 / 10, 2 / 10, 3 / 10, 4 / 10, 5 / 10, 6 / 10, 7 / 10, 8 / 10, 9 / 10, 1;

[0027] The minimum stiffness of the spring is obtained according to the maximum relative mid-span displacement of the simply supported beam specimen under the uniformly distributed load.

[0028] As a preferred embodiment of the present invention, the relative displacement coefficients δ at different positions along the beam span direction are i It can be determined according to the following formula:

[0029] δ i =|χ i -χ max |.

[0030] As a preferred embodiment of the present invention, the step of determining the stiffness distribution coefficient of the springs distributed along the rigid distribution beam includes:

[0031] Determine the deflection of the simply supported beam specimen at different positions under the uniformly distributed load according to the deflection formula of the simply supported beam specimen under the uniformly distributed load;

[0032] Determine the stiffness distribution coefficient γ of the spring along the rigid distribution beam according to the relative displacement coefficients at different positions i , according to the stiffness distribution coefficient γ i Determine the stiffness distribution coefficient of the spring along the rigid distribution beam, see Table 2,

[0033] Table 2. Spring stiffness distribution coefficient along beam span

[0034]

[0035] As a preferred embodiment of the present invention, when the simply supported beam specimens with different spans are tested, the stiffness of the smallest spring is the minimum stiffness k of the spring. min Given, the stiffness coefficient of the spring is given by linear interpolation according to Table 2.

[0036] As a preferred embodiment of the present invention, during the simulation test, the spring distribution beam is placed on the simply supported beam specimen, the spring contacts the simply supported beam specimen, and a concentrated load is applied to the rigid distribution beam of the spring distribution beam. The spring distribution beam converts the concentrated load into a uniformly distributed load, and applies the uniformly distributed load to the simply supported beam specimen through the spring.

[0037] As a preferred embodiment of the present invention, the springs are distributed at equal intervals.

[0038] A device for simulating the loading of a simply supported beam with a uniformly distributed unidirectional load. The method for simulating the loading of a simply supported beam with a uniformly distributed unidirectional load as described above uses the device to complete the test, comprising:

[0039] Support, on which the simply supported beam specimen is placed;

[0040] Servo-hydraulic jacks for providing controlled concentrated loads;

[0041] A spring distribution beam comprises a rigid distribution beam and a plurality of springs arranged at equal intervals at the bottom of the rigid distribution beam; the minimum stiffness of the springs and the stiffness distribution coefficient of the springs distributed along the rigid distribution beam are determined by the maximum theoretical deflection of the simply supported beam specimen; the springs are distributed along the rigid distribution beam with a stiffness that is greater in the middle and smaller at both ends;

[0042] Among them, the minimum stiffness of the spring is

[0043]

[0044] Where E is the elastic modulus of the beam, I is the section moment of inertia of the beam, l is the span of the beam specimen, and δ max is the relative displacement coefficient at the maximum position along the span direction of the simply supported beam specimen;

[0045] The stiffness distribution coefficient of the springs distributed along the rigid distribution beam is

[0046]

[0047] Where k i is the spring stiffness required at different positions, k min is the minimum stiffness of the spring, δ i is the relative displacement coefficient at different positions along the span of the beam;

[0048] During the simulation test, the servo hydraulic jack applies a concentrated load to the rigid distribution beam, and the rigid distribution beam and the spring convert the concentrated load into a uniformly distributed load and apply it to the simply supported beam specimen.

[0049] As a preferred embodiment of the present invention, the present invention further comprises:

[0050] a force sensor for monitoring the force applied by the servo hydraulic jack;

[0051] The reaction floor is provided with the support seat.

[0052] The reaction frame is erected on the reaction floor; the servo hydraulic jack is connected to the reaction frame, and a self-balancing system is formed between the reaction frame and the reaction floor.

[0053] The above technical solution of the present invention has the following advantages over the prior art:

[0054] The present invention discloses a method and apparatus for simulating unidirectional uniformly distributed loads on a simply supported beam. A spring distribution beam is designed by combining a rigid distribution beam with a spring to convert the concentrated load provided by a servo-hydraulic jack into a uniformly distributed load, which is then applied to the simply supported beam specimen. The minimum stiffness of the springs on the designed spring distribution beam is determined based on the maximum theoretical deflection of the simply supported beam specimen. The stiffness distribution coefficient of the springs on the designed spring distribution beam is also determined. When testing beams of different spans, different spring distribution beams are designed to evenly distribute the load provided by the servo-hydraulic jack across the simply supported beam specimen, completing the simulation of the uniformly distributed load. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to make the contents of the present invention more clearly understood, the present invention is further described in detail below based on specific embodiments of the present invention in conjunction with the accompanying drawings.

[0056] Figure 1 It is a schematic diagram of the workflow of a unidirectional uniformly distributed load loading simulation method for a simply supported beam of the present invention.

[0057] Figure 2 It is a schematic diagram of a unidirectional uniformly distributed load simulation device for a simply supported beam of the present invention.

[0058] Explanation of the reference numerals in the accompanying drawings in the specification: 1. Reaction floor; 2. Support; 3. Reaction frame; 4. Force sensor; 5. Servo hydraulic jack; 6. Spring distribution beam; 61. Rigid distribution beam; 62. Spring; 7. Simply supported beam specimen. DETAILED DESCRIPTION

[0059] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. However, the embodiments are not intended to limit the present invention.

[0060] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, features defined as "second" and "first" may explicitly or implicitly include one or more of the features. In the description of the present invention, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0061] In the present invention, unless otherwise expressly specified or limited, terms such as "mounted," "connected," "connect," and "fixed" should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0062] Unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may be such that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. In addition, the term "comprising" is intended to cover non-exclusive inclusions, such as a process, method, system, product, or apparatus that includes a series of steps or units, is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products, or apparatuses.

[0063] Example 1

[0064] Reference Figures 1-2 As shown, an embodiment of a method for simulating unidirectional uniformly distributed load loading on a simply supported beam according to the present invention specifically includes:

[0065] Before the simulation test, the maximum theoretical deflection of the simply supported beam specimen 7 to be tested is obtained.

[0066] According to the maximum theoretical deflection of the simply supported beam specimen 7 , the minimum stiffness of the spring 62 and the stiffness distribution coefficient of the spring 62 distributed along the stiffness distribution beam 61 are determined.

[0067] According to the stiffness distribution coefficient of the springs 62 along the rigid distribution beam 61 , a plurality of the springs 62 are evenly distributed on one side of the rigid distribution beam 61 to form a spring distribution beam 6 for testing the simply supported beam specimen 7 .

[0068] Specifically, the step of obtaining the maximum theoretical deflection of the simply supported beam specimen 7 includes:

[0069] According to the span of the simply supported beam specimen 7 and the size of the uniformly distributed load, the bending moment distribution of the simply supported beam specimen 7 under the uniformly distributed load is obtained.

[0070] The bending moment of the simply supported beam specimen 7 under the uniformly distributed load is distributed along the simply supported beam specimen 7 as follows:

[0071]

[0072] Where M is the bending moment, q is the uniformly distributed load, and l is the span of the beam specimen.

[0073] From the mechanics of materials, we know that the deflection curve and bending moment satisfy the equilibrium differential equation

[0074]

[0075] Where E is the elastic modulus of the beam, and I is the section moment of inertia of the beam.

[0076] The deflection curve formula is obtained based on the bending moment distribution. Substituting equation (1) into equation (2) and solving the equilibrium differential equation and substituting the displacement boundary conditions, the deflection curve formula of the simply supported beam specimen 7 under uniformly distributed load can be obtained.

[0077]

[0078] Substitute the parameters of different positions of the simply supported beam specimen 7 into the deflection curve formula to obtain the theoretical deflection coefficients at different positions along the span direction of the simply supported beam specimen 7. In formula (3), q is used as the load variable. As the deflection constant, the rest is the deflection position variable; by substituting the different position parameters of the simply supported beam specimen 7 into the deflection position variable in formula (3), the theoretical deflection coefficient χ at different positions along the span direction of the simply supported beam specimen 7 can be obtained. i See Table 1.

[0079] Table 1. Deflection coefficient χ under uniformly distributed load i

[0080]

[0081] The step of determining the minimum stiffness of the spring 62 includes:

[0082] The deflection formula of the simply supported beam specimen 7 under the uniform load is obtained based on the uniform load and the theoretical deflection coefficient. The deflection of the simply supported beam specimen 7 under the uniform load can be expressed as the uniform load multiplied by the deflection invariant and then multiplied by the deflection coefficient χ i Right now

[0083]

[0084] According to the deflection formula of the simply supported beam specimen 7 under uniform load and Hooke's law, the stiffness of the spring 62 required at different positions of the simply supported beam specimen 7 is obtained. The stiffness of the spring 62 required at different positions is determined according to Hooke's law:

[0085]

[0086] Where, δ i is the relative displacement coefficient at different positions along the span of the beam, and i is 0, 1 / 10, 2 / 10, 3 / 10, 4 / 10, 5 / 10, 6 / 10, 7 / 10, 8 / 10, 9 / 10, and 1.

[0087] δ i It can be determined according to the following formula

[0088] δ i =|χ i -χ max | (6)

[0089] The minimum stiffness of the spring 62 is obtained from the maximum relative mid-span displacement of the simply supported beam specimen 7 under the uniformly distributed load. The minimum stiffness of the spring 62 in the spring distribution beam 6 is obtained from the maximum relative mid-span displacement of the simply supported beam under the uniformly distributed load.

[0090]

[0091] The step of determining the stiffness distribution coefficient of the springs 62 distributed along the rigid distribution beam 61 includes:

[0092] According to the deflection formula of the simply supported beam specimen 7 under uniform load, the deflection of the simply supported beam specimen 7 at different positions under uniform load is determined. According to the deflection calculation formula (4) of the simply supported beam specimen 7 under uniform load, the deflection of the simply supported beam at different positions under uniform load is determined.

[0093] Then, the stiffness of the spring 62 required at different positions is determined according to equation (5).

[0094] The stiffness distribution coefficient of the spring 62 along the rigid distribution beam 61 is determined according to the relative displacement coefficients at different positions. i Determine the stiffness distribution coefficient of the spring along the rigid distribution beam 61,

[0095]

[0096] Finally, the stiffness distribution coefficient of the spring 62 along the rigid distribution beam 61 is determined according to formula (8), as shown in Table 2.

[0097] Table 2. Spring stiffness distribution coefficient along beam span

[0098]

[0099] When the simply supported beam specimens 7 of different spans are tested, the minimum stiffness of the spring 62 is given by formula (7), and the stiffness coefficient of the spring 62 is given by linear interpolation according to Table 2.

[0100] During the test, the concentrated load is controlled by the servo hydraulic jack, the load state is monitored by the force sensor 4, and finally the load provided by the servo hydraulic jack is evenly distributed on the simply supported beam specimen 7 by the spring distribution beam 6 to complete the simulation of uniformly distributed load.

[0101] Example 2

[0102] Reference Figures 1-2 As shown, an embodiment of a unidirectional uniformly distributed load loading simulation device for a simply supported beam according to the present invention uses any of the above-mentioned unidirectional uniformly distributed load loading simulation methods for a simply supported beam, including:

[0103] The reaction floor 1 can be selected as a reaction floor 1 or a reaction groove according to laboratory conditions. If the laboratory does not have a reaction floor 1 or a reaction groove, an I-beam or a box-shaped steel beam can be used as a ground beam instead.

[0104] Support 2, the simply supported beam specimen 7 is placed on the support 2, and the support 2 is mounted on the reaction floor 1. Preferably, there are two supports 2, which are respectively arranged at the two ends of the simply supported beam specimen 7. The supports 2 can use concrete supports 2 or steel supports 2 according to conditions. During the test, the position between the supports 2 is adjusted according to the span of the simply supported beam specimen 7, and the supports 2 are fixed to the reaction floor 1 by bolt rods. Furthermore, the simply supported beam specimen 7 is connected to the two supports 2 in different ways, one end of which is connected by a fixed hinge support 2, and the other end is connected by a rolling hinge support 2. For the reliability between the simply supported beam specimen 7 and the support 2, the simply supported beam specimen 7, the hinge support 2 and the support 2 can be fixed to the reaction floor 1 by bolt rods.

[0105] The reaction frame 3 is mounted on the reaction floor 1. The servo-hydraulic jack 5 is connected to the reaction frame 3, forming a self-balancing system between the reaction frame 3 and the reaction floor 1. The reaction frame 3 is composed of two I-beam columns and an I-beam crossbeam. The I-beam crossbeam and columns are bolted together to form a gantry. The bolted connection between the reaction frame 3 and the reaction floor 1 forms a complete self-balancing system.

[0106] The servo hydraulic jack 5 is used to provide a concentrated load. The servo hydraulic jack 5 is installed on the reaction frame 3 to apply downward force. During the test, the servo hydraulic jack 5 is located directly above the simply supported beam specimen 7.

[0107] The spring distribution beam 6 is used to realize the conversion of concentrated load to uniformly distributed load. The spring distribution beam 6 comprises a rigid distribution beam 61 and a plurality of springs 62 arranged at the bottom of the rigid distribution beam 61 at equal intervals.

[0108] The rigid distribution beam 61 is welded with I-beams or steel structural materials, and its bending stiffness should be much greater than that of the simply supported beam specimen 7 to prevent the rigid distribution beam 61 from being deformed too much during the test.

[0109] The minimum stiffness of the spring 62 and the stiffness distribution coefficient of the spring 62 distributed along the rigid distribution beam 61 are determined by the maximum theoretical deflection of the simply supported beam specimen 7. The springs 62 are distributed along the rigid distribution beam 61 with a stiffness that is greater in the middle and smaller at both ends. The springs 62 are preferably springs, with varying stiffnesses selected according to the design. The springs 62 are evenly spaced and installed on one side of the rigid distribution beam 61 with the designed stiffness distribution coefficient.

[0110] The minimum stiffness of the spring 62 is determined by the span, elastic modulus, and section moment of inertia of the simply supported beam specimen 7 .

[0111] Among them, the minimum stiffness of the spring is

[0112]

[0113] Where E is the elastic modulus of the beam, I is the section moment of inertia of the beam, l is the span of the beam specimen, and δ i is the relative displacement coefficient at different positions along the span of the beam.

[0114] The stiffness distribution coefficient of the springs distributed along the rigid distribution beam is

[0115]

[0116] Where k i is the spring stiffness required at different positions, k min is the minimum stiffness of the spring, δ maxis the relative displacement coefficient at the maximum position along the span direction of the simply supported beam specimen.

[0117] The springs 62 are distributed along the rigid distribution beam 61, with spring stiffness being greater in the middle and lower at both ends. The springs are welded to the rigid distribution beam 61. Different springs 62 are installed on the rigid distribution beam 61 according to their distribution coefficients to form the spring distribution beam 6, which is then used in conjunction with the servo hydraulic jack 5 to simulate uniformly distributed loads.

[0118] During the test, the spring 62 of the spring distribution beam 6 contacts the simply supported beam specimen 7, and the servo hydraulic jack 5 applies a concentrated load to the rigid distribution beam 61. The rigid distribution beam 61 and the spring 62 convert the concentrated load into a uniformly distributed load and apply it to the simply supported beam specimen 7.

[0119] A force sensor 4 is used to monitor the force applied by the servo hydraulic jack 5. The force sensor 4 is connected to the reaction frame 3 via bolts, and the servo hydraulic jack 5 and the force sensor 4 are connected via bolts and an adapter plate.

[0120] Before the simulation test, the position of the support 2 on the reaction floor 1 is adjusted according to the span of the simply supported beam specimen 7 to be tested, and the support 2 is fixedly connected to the reaction floor 1. The simply supported beam specimen 7 to be tested is placed on the support 2, and the simply supported beam specimen 7 is connected to the support 2. The designed spring distribution beam 6 is placed on the simply supported beam specimen 7, and the spring 62 is in contact with the simply supported beam specimen 7. The force sensor 4 is connected to the reaction frame 3 by bolts, and the servo hydraulic jack 5 is connected to the force sensor 4 by bolts and an adapter plate.

[0121] During the simulation test, the servo hydraulic jack 5 applies a concentrated load to the spring distribution beam 6 placed on the simply supported beam specimen 7. The spring distribution beam 6 designed by combining the rigid distribution beam 61 and the spring 62 converts the concentrated load provided by the servo hydraulic jack 5 into a uniformly distributed load and applies it to the simply supported beam specimen 7 to be tested.

[0122] The size of the concentrated load is controlled by the servo hydraulic jack 5, the force state and load size of the concentrated load are monitored by the force sensor 4, and finally the load provided by the servo hydraulic jack 5 is evenly distributed on the simply supported beam specimen 7 through the spring distribution beam 6 to complete the simulation of uniformly distributed load.

[0123] The above technical solution of the present invention has the following advantages over the prior art:

[0124] The present invention discloses a method and apparatus for simulating the application of a unidirectional uniformly distributed load to a simply supported beam. A device for simulating the application of a unidirectional uniformly distributed load to a simply supported beam specimen is designed using a reaction frame, a reaction floor, a servo-hydraulic jack, and a spring distribution beam. A spring distribution beam is designed by combining a rigid distribution beam with a spring to convert the concentrated load provided by the servo-hydraulic jack into a uniformly distributed load, which is then applied to the simply supported beam specimen. The minimum stiffness of the springs on the designed spring distribution beam is determined based on the maximum theoretical deflection of the simply supported beam specimen. The stiffness distribution coefficient of the springs on the designed spring distribution beam is then determined. Different spring distribution beams are designed for testing beams of different spans. During the test, the load is controlled by the servo-hydraulic jack, and the load status is monitored by the force sensor. Finally, the load provided by the servo-hydraulic jack is evenly distributed across the simply supported beam specimen via the spring distribution beam, completing the simulation of the uniformly distributed load.

[0125] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications arising therefrom remain within the scope of protection of the present invention.

Claims

1. A method for simulating unidirectional uniformly distributed load loading on a simply supported beam, characterized in that: include: Before the simulation test, obtain the maximum theoretical deflection of the simply supported beam specimen to be tested; Determining the minimum stiffness of the spring and the stiffness distribution coefficient of the springs distributed along the stiffness distribution beam according to the maximum theoretical deflection of the simply supported beam specimen; According to the stiffness distribution coefficient of the springs along the rigid distribution beam, a plurality of the springs are arranged at the bottom of the rigid distribution beam according to the stiffness distribution coefficient to form a spring distribution beam for simulating uniformly distributed load; Among them, the minimum stiffness of the spring is Where E is the elastic modulus of the beam, I is the section moment of inertia of the beam, l is the span of the beam specimen, and δ max is the relative displacement coefficient at the maximum position along the span direction of the simply supported beam specimen; The stiffness distribution coefficient of the springs distributed along the rigid distribution beam is Where k i is the spring stiffness required at different positions, k min is the minimum stiffness of the spring, δ i is the relative displacement coefficient at different positions along the span of the beam.

2. The method for simulating unidirectional uniform load loading of a simply supported beam according to claim 1, characterized in that: Obtaining the maximum theoretical deflection of the simply supported beam specimen to be tested includes: According to the span of the simply supported beam specimen and the size of the uniformly distributed load, the bending moment distribution of the simply supported beam specimen under the uniformly distributed load is obtained; A deflection curve formula is obtained based on the bending moment distribution; The parameters of different positions of the simply supported beam specimen are brought into the deflection curve formula to obtain the theoretical deflection coefficient χ at different positions along the span direction of the simply supported beam specimen. i , see Table 1, Table 1. Deflection coefficient χ under uniformly distributed load i 3. The method for simulating unidirectional uniformly distributed load loading on a simply supported beam according to claim 2, characterized in that: The step of determining the minimum stiffness of the spring comprises: According to the uniformly distributed load and the theoretical deflection coefficient, the deflection formula of the simply supported beam specimen under the uniformly distributed load is obtained; According to the deflection formula of the simply supported beam specimen under uniformly distributed load and Hooke's law, the spring stiffness k required at different positions of the simply supported beam specimen is obtained. i , Where, δ i is the relative displacement coefficient at different positions along the span of the beam, i is 0, 1 / 10, 2 / 10, 3 / 10, 4 / 10, 5 / 10, 6 / 10, 7 / 10, 8 / 10, 9 / 10, 1; The minimum stiffness of the spring is obtained according to the maximum relative mid-span displacement of the simply supported beam specimen under the uniformly distributed load.

4. The method for simulating unidirectional uniformly distributed load loading on a simply supported beam according to claim 3, characterized in that: The relative displacement coefficient δ at different positions along the beam span direction is i It can be determined according to the following formula: d i =|x i -x max |。 5. The method for simulating unidirectional uniform load loading of a simply supported beam according to claim 3, characterized in that: The step of determining the stiffness distribution coefficient of the springs distributed along the rigid distribution beam comprises: Determine the deflection of the simply supported beam specimen at different positions under the uniformly distributed load according to the deflection formula of the simply supported beam specimen under the uniformly distributed load; Determine the stiffness distribution coefficient γ of the spring along the rigid distribution beam according to the relative displacement coefficients at different positions i , according to the stiffness distribution coefficient γ i Determine the stiffness distribution coefficient of the spring along the rigid distribution beam, see Table 2, Table 2. Spring stiffness distribution coefficient along beam span 6. The method for simulating unidirectional uniform load loading of a simply supported beam according to claim 5, characterized in that: When the simply supported beam specimens with different spans are tested, the stiffness of the smallest spring is calculated according to the minimum stiffness k of the spring. min Given, the stiffness coefficient of the spring is given by linear interpolation according to Table 2.

7. The method for simulating unidirectional uniform load loading of a simply supported beam according to claim 1, characterized in that: During the simulation test, the spring distribution beam is placed on the simply supported beam specimen, the spring contacts the simply supported beam specimen, and a concentrated load is applied to the rigid distribution beam of the spring distribution beam. The spring distribution beam converts the concentrated load into a uniformly distributed load and applies the uniformly distributed load to the simply supported beam specimen through the spring.

8. The method for simulating unidirectional uniform load loading of a simply supported beam according to claim 1, characterized in that: The springs are distributed at equal intervals.

9. A device for simulating the loading of a simply supported beam with a uniformly distributed unidirectional load, wherein the method for simulating the loading of a simply supported beam with a uniformly distributed unidirectional load according to any one of claims 1 to 8 is used to complete the test, characterized in that: include: Support, on which the simply supported beam specimen is placed; Servo-hydraulic jacks for providing controlled concentrated loads; A spring distribution beam comprises a rigid distribution beam and a plurality of springs arranged at equal intervals at the bottom of the rigid distribution beam; the minimum stiffness of the springs and the stiffness distribution coefficient of the springs distributed along the rigid distribution beam are determined by the maximum theoretical deflection of the simply supported beam specimen; the springs are distributed along the rigid distribution beam with a stiffness that is greater in the middle and smaller at both ends; Among them, the minimum stiffness of the spring is Where E is the elastic modulus of the beam, I is the section moment of inertia of the beam, l is the span of the beam specimen, and δ max is the relative displacement coefficient at the maximum position along the span direction of the simply supported beam specimen; The stiffness distribution coefficient of the springs distributed along the rigid distribution beam is Where k i is the spring stiffness required at different positions, k min is the minimum stiffness of the spring, δ i is the relative displacement coefficient at different positions along the span of the beam; During the simulation test, the servo hydraulic jack applies a concentrated load to the rigid distribution beam, and the rigid distribution beam and the spring convert the concentrated load into a uniformly distributed load and apply it to the simply supported beam specimen.

10. The unidirectional uniformly distributed load simulation device for a simply supported beam according to claim 9, characterized in that: Also includes: a force sensor for monitoring the force applied by the servo hydraulic jack; a reaction floor, on which the support is mounted; Reaction frame, erected on the reaction floor; The servo hydraulic jack is connected to the reaction frame, and a self-balancing system is formed between the reaction frame and the reaction floor.

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