Test device and test method for explosion resistance of beam-type components based on squeeze film effect

Abstract

The present invention discloses a test device and a test method for explosion resistance of beam-type components based on the squeeze film effect. The device connects a plurality of circular steel pipes symmetrically arranged on both sides of the longitudinal direction of the beam-type structure to pads located on both sides of the longitudinal direction of the beam-type component through circular grooves. At the same time, rollers are arranged to enable the beam to freely expand and contract longitudinally after being subjected to a lateral load. The data acquisition device acquires the compression strain data ε monitored by the resistance strain gauge at different times. i The vertical displacement data monitored by the displacement sensor are used for calculation and statistical analysis to obtain the size of the compression film effect corresponding to the vertical displacement of the beam component at different times under the explosion load, as well as the deflection-time relationship of the beam component under the explosion load and the compression film effect. This can be used to quantitatively determine the influence of the compression film effect on the explosion-resistant bearing capacity of the beam component, thereby making reasonable use of the bearing capacity of the beam component and saving manufacturing materials and costs.

Description

Technical Field

[0001] The invention relates to a beam-type component explosion resistance test device and a test method based on a squeeze film effect, and belongs to the technical field of beam-type component explosion resistance testing. Background Art

[0002] In explosion-resistant structures, weakly connected frame beams or plates constrained by frames with analogous stiffness should not be simplified as simply supported or clamped beam-type components. Under the action of the explosion, the lower edge of the beam-type component is stretched. In some cases, its longitudinal deformation is constrained by the support, which causes compression at the end of the beam-type component and limits the elongation of the tension zone, while generating longitudinal pressure inside the structure. And because the longitudinal pressure belongs to the eccentric force of the tension zone at the bottom of the beam-type component, it will further generate a bending moment at the contact boundary between the support and the component. At the same time, the combined effect of longitudinal pressure and bending moment (i.e., the squeeze film effect) changes with the deflection of the beam-type component, and causes changes in the resistance and failure mode of the structure.

[0003] Generally speaking, the squeeze film effect will significantly increase the resistance of beam components, while the traditional yield line theory does not consider the influence of the squeeze film effect on the resistance of beam components. For example, the existing design specifications regard the influence of the squeeze film effect on the resistance as a safety reserve without in-depth research, or generally multiply the structural resistance obtained based on the yield line theory by a coefficient of 1.5 to 2.0, resulting in a serious underestimation of the structural bearing capacity of beam components, which makes it difficult to reasonably utilize the bearing capacity and increases the manufacturing materials and manufacturing costs of beam components. Therefore, clarifying the mechanism of the squeeze film effect on the structural resistance of beam components can more accurately predict the structural bearing capacity (resistance) of beam components, so that the bearing capacity of beam components can be reasonably utilized and save manufacturing materials and manufacturing costs. Summary of the invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and to provide a test device and a test method for the explosion resistance of beam-type components based on the squeeze film effect, in order to obtain relevant experimental data for studying and clarifying the mechanism of action of the squeeze film effect on the structural resistance of beam-type components.

[0005] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0006] In a first aspect, the present invention provides a beam-type component anti-explosion test device based on the squeeze film effect, comprising a concrete pier and a beam-type component located on the rolled concrete pier, and further comprising:

[0007] A film-pressing loading mechanism, the film-pressing loading mechanism comprising pads respectively attached to the longitudinal end walls of the beam-type component below the neutral plane, a plurality of circular steel pipes between the pads and the beam-type component, and rollers symmetrically arranged on both longitudinal sides of the bottom of the beam-type component;

[0008] A plurality of resistance strain gauges, each of which is provided at a cross section of the circular steel pipe on at least one side in the longitudinal direction of the beam-type component, and is used to monitor the compressive strain data of the circular steel pipe;

[0009] A plurality of displacement sensors, which are arranged directly below the beam-type component and spaced longitudinally to monitor the vertical displacement of different parts of the beam-type component; and a data acquisition device, which is used to collect the compressive strain data monitored by each resistance strain gauge and the vertical displacement data monitored by each displacement sensor at different moments when the beam-type component is subjected to the combined action of the explosion load and the squeeze film effect, so as to provide for subsequent calculation and statistical analysis in combination with the known elastic modulus, diameter, length L, Poisson's ratio u, loading angle α of the circular steel pipe and the distance di between the axis of each circular steel pipe and the neutral plane, so as to obtain the longitudinal total constraint force data N and the total resistance bending moment data M provided by all the circular steel pipes for the beam-type component at the different moments, thereby obtaining the squeeze film effect size corresponding to the vertical displacement of the beam-type component at different moments under the action of the explosion load, and the deflection-time relationship of the beam-type component under the explosion load and the squeeze film effect.

[0010] Furthermore, two pads are provided on both longitudinal sides of the beam-type component, one of the pads is tightly combined with the end walls on both sides of the beam-type component through high-strength epoxy resin, and the side walls of the pads are evenly provided with semicircular first grooves, and the two are tightly combined to form circular grooves. At the same time, the diameter of the circular steel pipe is suitable for the horizontal groove for the circular steel pipe to be inserted. One of the pads is tightly combined with the end wall of the beam through high-strength epoxy resin, and the other pad is tightly combined with the concrete pier.

[0011] Furthermore, the number of the circular steel pipes is consistent with the circular groove, and the upper end surface of the pad coincides with the horizontal center axis of the beam-type component.

[0012] Furthermore, the beam-type component is horizontally mounted on two rollers arranged at intervals horizontally, so that the beam can freely expand and contract longitudinally after the explosion. The rollers are erected above the concrete piers, and the concrete piers are fixed to the rigid ground. A rigid crossbeam is also connected between the two concrete piers. The rigid crossbeam is fixed to the concrete piers through a steel plate. A plurality of displacement sensors are installed on the rigid crossbeam at a position directly below the beam-type component, and are evenly distributed from the position corresponding to the longitudinal center of the beam-type component toward one of the concrete piers.

[0013] Furthermore, the number of circular steel pipes symmetrically arranged on both sides of the beam-type component in the longitudinal direction is three, and the axial distance between two adjacent circular steel pipes in the vertical direction is d.

[0014] The test device and test method for the explosion resistance of beam-type components based on the squeeze film effect as described in claim 1 are characterized by: further comprising a calculation and analysis device, which executes the relationship between stress and strain when the circular cross-section is subjected to a uniformly distributed load and obtains the longitudinal total constraint force data N and the total resistance bending moment data M, as well as the deflection-time relationship of the beam-type component under the explosion load and the squeeze film effect.

[0015] Furthermore, the test method of the beam-type component anti-explosion test device based on the squeeze film effect as described in any one of the above items comprises the steps of:

[0016] S1. Arrange the test device and set the explosive at a certain height just above the center of the beam member;

[0017] S2, detonating the explosive to apply an explosion load to the upper surface of the beam member;

[0018] S3. The data acquisition and analysis device is used to collect the compressive strain data monitored by each resistance strain gauge and the vertical displacement monitored by each displacement sensor at different times when the beam-type component is subjected to the explosion load, so as to carry out subsequent calculation and statistical analysis in combination with the known elastic modulus, diameter, length L, Poisson's ratio, loading angle α of the circular steel pipe and the distance di between the axis of each circular steel pipe and the neutral plane, so as to obtain the longitudinal total constraint force data N and the total resistance bending moment data M provided by all the circular tie rods to the beam-type component at the different times, so as to obtain the size of the compression film effect corresponding to the vertical displacement of the beam-type component at different times under the explosion load, and the deflection-time relationship of the beam-type component under the explosion load and the compression film effect.

[0019] Furthermore, in step S3, the longitudinal total restraint force data N and the total resistance bending moment data M are calculated based on the relationship between stress and strain when the circular cross section is subjected to a uniformly distributed load, specifically:

[0020] From bottom to top, the longitudinal restraint provided by each of the two symmetrical circular steel tubes 7 is:

[0021]

[0022] Total longitudinal restraint provided by all circular steel tubes 7:

[0023] N=∑N i Formula (2);

[0024] From bottom to top, the bending moment resistance provided by each of the two symmetrical circular steel tubes 7 is:

[0025] M i =Nd i Formula (3);

[0026] Total moment resistance provided by all circular ties:

[0027] M=∑M i Formula (4);

[0028] Substituting formula (1) into formula (2) yields the total longitudinal restraint force N provided by all circular steel tubes 7, and substituting formula (3) into formula (4) yields the total resistance bending moment M provided by all circular steel tubes 7, where i is 1, 2, 3, ..., n.

[0029] Furthermore, in step S3, the acquisition device acquires a compressive strain data detected by the corresponding resistance strain gauge and a vertical displacement data detected by the displacement sensor every 0.001 milliseconds.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The present invention provides a test device and a test method for explosion resistance of beam-type components based on the squeeze film effect. A plurality of circular steel pipes symmetrically arranged on both sides of the longitudinal direction of the beam-type structure are connected to pads located on both sides of the longitudinal direction of the beam-type component through circular grooves. At the same time, rollers are arranged to enable the beam to freely expand and contract longitudinally after being subjected to a lateral load. The data acquisition device collects the compression strain data ε monitored by the resistance strain gauge at different times. i And the vertical displacement data monitored by the displacement sensor for subsequent comparison with the known elastic modulus E of the circular steel pipe s , diameter D, length L, Poisson's ratio μ, loading angle α and the distance d between the axis of each circular steel tube and the neutral plane i By combining calculation and statistical analysis, the total longitudinal restraint force data N and the total resistance bending moment data M provided by all circular steel tubes for the beam-type components at the different times are obtained, so as to obtain the size of the compression film effect corresponding to the vertical displacement of the beam-type components at different times under the explosion load, and the deflection-time relationship of the beam-type components under the explosion load and the compression film effect, and thereby quantitatively judge the influence of the compression film effect on the explosion resistance bearing capacity of the beam-type components, thereby making reasonable use of the bearing capacity of the beam-type components and saving manufacturing materials and manufacturing costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A longitudinal cross-sectional view of an embodiment of the present invention;

[0033] Figure 2 The figure is a schematic diagram of the coordination between the pad, the circular steel pipe and the beam member;

[0034] Figure 3 is a lateral view of the pad;

[0035] Figure 4 Schematic diagram of the working principle of pads, circular steel pipes and beam components.

[0036] In the figure: 1, compression film loading mechanism; 2, resistance strain gauge; 3, displacement sensor; 4, roller; 5, pad; 6, steel plate; 7, round steel pipe; 8, splint; 100, beam member; 200, rolling concrete pier; 300, rigid beam; 111, first groove; 121, second groove. DETAILED DESCRIPTION

[0037] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0038] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions 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", "second", and the like are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", and the like may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0039] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0040] Example 1

[0041] The invention provides a beam-type component anti-explosion test device based on the squeeze film effect.

[0042] In the embodiment of the present invention, Figures 1 to 4 As shown, the beam-type component anti-explosion test device based on the squeeze film effect includes a squeeze film loading mechanism 1, a plurality of resistance strain gauges 2, a plurality of displacement sensors 3 and a data acquisition device (not shown).

[0043] The compression film loading mechanism 1 comprises a pad 5 respectively fitted with the longitudinal end wall of the beam component 100 below the neutral plane, a clamping plate 8, a plurality of circular steel pipes 7 between the pad 5 and the clamping plate 8, and rollers 4 symmetrically arranged on both longitudinal sides of the bottom of the beam component 100. The facing walls of the pad 5 and the pad 8 are respectively formed with a first semicircular groove 111 and a second groove 121 for the circular steel pipe 7 to be inserted, so as to prevent the circular steel pipe 7 from sliding and dislocating during the test. The pad 5 is tightly combined with the beam end wall through high-strength epoxy resin, and the pad 8 is tightly combined with the concrete pier 200. At the same time, the rollers 4 symmetrically arranged on both longitudinal sides of the bottom of the beam component 100 are used so that the beam component 100 can freely expand and contract longitudinally after the explosion, so that the steel pipe 7, the pad 5, the clamping plate 8 and the beam component 100 swing in unison, and the longitudinal constraint of the circular steel pipe 7 forms a combined longitudinal pressure and bending moment (i.e., compression film effect) on the end of the beam component 100. The circular steel tubes 7 located at least on one side of the longitudinal direction of the beam-type component 100 are respectively equipped with the resistance strain gauges 2 for monitoring the compressive strain data ε of the circular steel tubes 7. i The plurality of displacement sensors 3 are arranged below the beam member 100 and are spaced apart longitudinally to monitor the vertical displacement of different parts of the beam member 100. The data acquisition device is used to collect the compression strain data ε monitored by each resistance strain gauge 2 at different moments when the beam member 100 is subjected to the combined action of the explosion load and the squeeze film effect. i And the vertical displacement data monitored by each displacement sensor 3. For subsequent comparison with the known elastic modulus E of the circular steel pipe 7 s , diameter D, length L, Poisson's ratio μ, loading angle α and the distance di (i.e., the lever arm) between the axis of each circular steel tube 7 and the neutral plane are combined for calculation and statistical analysis to obtain the longitudinal total constraint force data N and the total resistance bending moment data M provided by all the circular steel tubes 7 for the beam component 100 at the different times (the longitudinal total constraint force data N and the total resistance bending moment data M provided by the circular steel tubes 7 for the beam component 100 are finally acted on the end of the beam component 100 through the pads 5 and 8 to form a combined longitudinal pressure and bending moment), so as to obtain the size of the compression film effect corresponding to the vertical displacement of the beam component 100 at different times under the explosion load, and the deflection-time relationship of the beam component 100 under the explosion load and the compression film effect, and thereby quantitatively judge the influence of the compression film effect on the explosion resistance bearing capacity of the beam component, so that the bearing capacity of the beam component 100 can be reasonably utilized and the manufacturing materials and manufacturing costs can be saved.

[0044] In the embodiment of the present invention, the number of the circular steel tubes 7 can be two, three, four, five or more, and the diameter of the circular steel tube 7 is suitable for the circular groove formed by the semicircular first groove 111 of the cushion block 5 and the semicircular second groove 121 of the cushion block 8, so as to allow the circular steel tube 7 to be inserted, so as to prevent the circular steel tube 7 from sliding and dislocating during the test. Specifically, the number of the circular steel tubes 7 is preferably consistent with the semicircular first groove 111 and the second groove 121, the length of the circular steel tube 7 is consistent with the width of the cushion block 5 and the cushion block 7, and the axis extension line of the circular steel tube 7 is preferably perpendicular to the central axis of the cushion block 5 and the cushion block 8, so as to facilitate the determination of the distance di between the axis of the round steel tube 7 and the neutral plane.

[0045] In the embodiment of the present invention, the pad 8 is tightly combined with the end wall of the beam member 100 by high-strength epoxy resin. The beam member 100 is horizontally mounted on two horizontally spaced rollers 4. The rollers 4 only provide vertical support force and do not limit the horizontal movement and bending of the beam, so that the beam member 100 can freely expand and contract longitudinally after the explosion. In the embodiment of the present invention, there are many ways to connect the rigid cross beam 300 to the concrete pier 200, such as through a snap-on structure, welding or through a threaded connection structure. It is preferably connected through a threaded connection structure. In a preferred embodiment, the rigid cross beam 300 is connected to the concrete pier 200 through a reserved bolt hole and a steel plate 6. It can be understood that the displacement sensor 3 is a prior art, and it has multiple implementation methods. A sliding wire resistance displacement meter is preferred. It can be connected to a data acquisition device via a data line or a wireless communication module (such as at least one of a WIFI communication module, a GPRS communication module or a Bluetooth communication module, etc.). By adjusting the sampling frequency of the data acquisition device, for example, a vertical displacement data detected by the corresponding displacement sensor 3 is collected every 0.001 milliseconds, and the corresponding deflections at different times are automatically recorded, thereby obtaining the deflection-time relationship curve of the beam component 100 during the test.

[0046] It can be understood that the resistance strain gauge 2 is a prior art, which is pasted at the cross section corresponding to the corresponding circular steel pipe 7, and is connected to the data acquisition device through a data line or a wireless communication module (such as at least one of a WIFI communication module, a GPRS communication module or a Bluetooth communication module, etc.), and by adjusting the sampling frequency of the data acquisition device, for example, a compression strain data ε detected by the corresponding resistance strain gauge 2 is collected every 0.001 milliseconds. i .

[0047] In the embodiment of the present invention, the beam-type component 100 is horizontally mounted on two rollers 4 arranged at intervals horizontally. The rollers 4 restrict the vertical movement of the two ends of the beam-type component 100, but do not restrict the horizontal movement and bending of the beam, so as to ensure that the beam-type component 100 can freely expand and contract in the longitudinal direction after being subjected to an explosion. The beam-type component 100 is preferably of uniform cross-section, and its cross-sectional shape is preferably rectangular or square. The rollers 4 stand above the concrete pier 200, and the concrete pier 200 is fixed to the rigid ground. A rigid crossbeam 300 is also connected between the two concrete piers 200, and the rigid crossbeam 300 is fixed to the concrete pier 200 by a steel plate 6. The number of the displacement sensors 3 can be two, three, four, five or more, such as Figure 1 As shown, there are three displacement sensors 3 installed at longitudinal intervals on the rigid cross beam 300 directly below the beam member 100. This can ensure accurate detection of the vertical displacement of the corresponding parts of the beam member 100 while preventing the displacement sensors 3 from being damaged by the shock wave of the explosion.

[0048] Preferably, the displacement sensors 3 are evenly distributed from the longitudinal center of the corresponding beam member 100 toward one of the concrete piers 200. The rigid cross beam 300 is made of angle steel, and its two ends are detachably connected to the concrete pier 200.

[0049] It can be understood that the total longitudinal restraint force data N and the total resistance bending moment data M can be calculated based on the relationship between stress and strain when the circular cross section is subjected to a uniformly distributed load, specifically:

[0050] From bottom to top, the longitudinal restraint force provided by each of the two symmetrical circular steel tubes 7 is:

[0051]

[0052] Total longitudinal restraint provided by all circular steel tubes 7:

[0053] N=∑N i Formula (2);

[0054] From bottom to top, the bending moment resistance provided by each of the two symmetrical circular steel tubes 7 is:

[0055] M i =Nd i Formula (3);

[0056] The total moment resistance provided by all the circular tie rods 14 is:

[0057] M=∑M i Formula (4);

[0058] Substituting formula (1) into formula (2) can obtain the total longitudinal restraint force N provided by all circular steel tubes 7, and substituting formula (3) into formula (4) can obtain the total resistance bending moment M provided by all circular steel tubes 7, where E s is the elastic modulus of the circular steel tube 7, D is the diameter of the circular steel tube 7, L is the length of the circular steel tube 7, μ is the Poisson's ratio of the circular steel tube 7, α is the loading angle when the circular steel tube 7 is subjected to a uniformly distributed load, di is the distance between the axis of the circular steel tube 7 and the neutral plane, all of which are known quantities, ε i is the compressive strain of the i-th circular steel tube 7 from bottom to top detected by the corresponding resistance strain gauge 2, where i is 1, 2, 3..., n.

[0059] Taking the case where there are three circular steel tubes 7 symmetrically arranged on both sides of the longitudinal direction of the beam-type component 100, and the distance between the axis of the circular steel tubes from bottom to top and the neutral plane of the beam is di (i.e., d1 corresponds to the distance between the first circular steel tube from bottom to top and the neutral plane of the beam), the total longitudinal restraint force provided by all the circular steel tubes 7 is:

[0060]

[0061] The total bending moment resistance provided by all the circular steel tubes 7 is:

[0062]

[0063] Specifically, it also includes a calculation and analysis device, which can perform the above calculation based on the relationship between stress and strain when the circular cross section is subjected to a uniformly distributed load and obtain the longitudinal total restraint force data N and the total resistance bending moment data M, as well as obtain the deflection-time relationship of the beam-type component 100 under the explosion load and the squeeze film effect, and quantitatively determine the influence of the squeeze film effect on the explosion resistance bearing capacity of the beam-type component. Specifically, the calculation and analysis device can be computer software stored in the memory of the data acquisition device, or it can be a device independent of the data acquisition device.

[0064] After introducing the implementation of the beam-type component anti-explosion test device based on the squeeze film effect of the present invention, the implementation of the beam-type component anti-explosion test method based on the squeeze film effect of the present invention will be introduced next. The specific structure of the beam-type component anti-explosion test device based on the squeeze film effect is shown in the above embodiment, and the repeated parts will not be repeated.

[0065] The present invention also proposes a test method for anti-explosion action of beam-type components based on the squeeze film effect, comprising the steps of:

[0066] S1. Arrange the test device and place explosives at a certain height just above the center of the beam member 100;

[0067] Specifically, the explosive is preferably TNT spherical explosive, which is suspended just above the longitudinal center of the beam component 100. The vertical distance between the explosive and the beam component 100 can be determined according to test requirements and in combination with factors such as the equivalent of the explosive and the material, length and cross-sectional size of the beam component 100.

[0068] S2, detonating explosives to apply an explosion load to the upper surface of the beam-type component 100 (i.e., generating an explosion shock wave effect on the beam-type component 100);

[0069] Specifically, there are multiple ways to detonate the explosives, so as to ensure the safety of the test and not affect the smooth progress of the test. For example, a No. 4 copper electric detonator can be used for remote central detonation, and after the explosives explode, the explosion load is mainly applied to the upper surface of the beam member 100; in addition, by changing the mass of the explosives, the explosion loads of different proportions of explosion distances can be obtained, and different magnitudes of explosion effects can be applied.

[0070] S3, using a data acquisition and analysis device to collect the compression strain data ε monitored by each resistance strain gauge 2 at different times when the beam-type component 100 is subjected to the explosion load i And the vertical displacement monitored by each displacement sensor 3 is used to compare with the known elastic modulus E of the circular steel pipe. s , diameter D, length L, Poisson's ratio μ, loading angle α and the distance di between the axis of each circular steel tube and the neutral plane are combined for calculation and statistical analysis to obtain the total longitudinal constraint force data N and the total resistance bending moment data M provided by all the circular steel tubes 7 for the beam component 100 at the different times, so as to obtain the size of the compression film effect corresponding to the vertical displacement of the beam component 100 at different times under the explosion load, and the deflection-time relationship of the beam component 100 under the explosion load and the compression film effect, and thereby quantitatively judge the influence of the compression film effect on the explosion-resistant bearing capacity of the beam component, so as to make reasonable use of the bearing capacity of the beam component 100, correctly guide the engineering explosion-resistant design, and save manufacturing materials and manufacturing costs.

[0071] In the embodiment of the present invention, in step S3, the longitudinal total restraint force data N and the total resistance bending moment data M can be calculated based on the relationship between stress and strain when the circular cross section is subjected to a uniformly distributed load, specifically:

[0072] From bottom to top, the longitudinal restraint force provided by each of the two symmetrical circular steel tubes 7 is:

[0073]

[0074] Total longitudinal restraint provided by all circular steel tubes 7:

[0075] N=∑N i Formula (2);

[0076] From bottom to top, the bending moment resistance provided by each of the two symmetrical circular steel tubes 7 is:

[0077] M i =Nd i Formula (3);

[0078] The total moment resistance provided by all the circular tie rods 14 is:

[0079] M=∑M i Formula (4);

[0080] Substituting formula (1) into formula (2) can obtain the total longitudinal restraint force N provided by all circular steel tubes 7, and substituting formula (3) into formula (4) can obtain the total resistance bending moment M provided by all circular steel tubes 7, where E s is the elastic modulus of the circular steel tube 7, D is the diameter of the circular steel tube 7, L is the length of the circular steel tube 7, μ is the Poisson's ratio of the circular steel tube 7, α is the loading angle when the circular steel tube 7 is subjected to a uniformly distributed load, di is the distance between the axis of the circular steel tube 7 and the neutral plane, all of which are known quantities, ε i is the compressive strain of the i-th circular steel tube 7 from bottom to top detected by the corresponding resistance strain gauge 2, where i is 1, 2, 3..., n.

[0081] Taking the case where there are three circular steel tubes 7 symmetrically arranged on both sides of the longitudinal direction of the beam-type component 100, and the distance between the axis of the circular steel tubes from bottom to top and the neutral plane of the beam is di (i.e., d1 corresponds to the distance between the first circular steel tube from bottom to top and the neutral plane of the beam), the total longitudinal restraint force provided by all the circular steel tubes 7 is:

[0082]

[0083] The total bending moment resistance provided by all the circular steel tubes 7 is:

[0084]

[0085] Alternatively, in step S2, the sampling frequency of the data acquisition device may be adjusted, for example, to collect a compression strain data ε detected by the corresponding resistance strain gauge 2 every 0.001 milliseconds. i For calculation, the vertical displacement data detected by the displacement sensor 3 is collected, and the deflection corresponding to different moments is automatically recorded, thereby obtaining the deflection-time relationship curve of the beam component 100 during the test.

[0086] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A beam-type component explosion resistance test device based on squeeze film effect, comprising a concrete pier and a beam-type component located on the rolled concrete pier, characterized in that: Also includes: A film-pressing loading mechanism (1), the film-pressing loading mechanism (1) comprising pads (5) respectively fitted with the longitudinal end walls of the beam-type component (100) at the parts below the neutral plane, a plurality of circular steel pipes (7) located between the pads (5) and the beam-type component (100), and rollers (4) symmetrically arranged at both longitudinal sides of the bottom of the beam-type component (100); A plurality of resistance strain gauges (2), each of which is installed on a cross section of the circular steel pipe (7) located on at least one side in the longitudinal direction of the beam-type component (100), and is used to monitor the compressive strain data of the circular steel pipe (7); A plurality of displacement sensors (3), the plurality of displacement sensors (3) being arranged directly below the beam member (100) and spaced apart in the longitudinal direction, and used to monitor the vertical displacement of different parts of the beam member (100); and a data acquisition device, the data acquisition device being used to collect the compressive strain data monitored by each resistance strain gauge (2) and the vertical displacement data monitored by each displacement sensor (3) at different moments when the beam member (100) is subjected to the combined action of the explosion load and the compression film effect, so as to provide for subsequent comparison with the circular steel pipe (7) The known elastic modulus, diameter, length L, Poisson's ratio u, loading angle α and distance di between the axis of each circular steel tube (7) and the neutral plane are combined for calculation and statistical analysis to obtain the longitudinal total restraint force data N and total resistance bending moment data M provided by all the circular steel tubes (7) for the beam-type component (100) at the different moments, thereby obtaining the size of the compression film effect corresponding to the vertical displacement of the beam-type component (100) at different moments under the action of the explosion load, and the deflection-time relationship of the beam-type component (100) under the explosion load and the compression film effect; Two cushion blocks (5) are provided on both sides of the longitudinal direction of the beam-type component (100); one cushion block (5) is tightly combined with the end walls of both sides of the beam-type component (100) through high-strength epoxy resin; the side walls of the cushion blocks (5) are uniformly provided with semicircular first grooves, and the two are tightly combined to form a circular groove; at the same time, the diameter of the circular steel pipe (7) is suitable for the horizontal groove so that the circular steel pipe (7) can be inserted; one cushion block (5) is tightly combined with the beam end wall through high-strength epoxy resin, and the other cushion block (5) is tightly combined with the concrete pier; The number of the circular steel pipes (7) is consistent with the number of the circular grooves, and the upper end surface of the cushion block (5) coincides with the horizontal center axis of the beam member (100); The beam-type component (100) is horizontally mounted on two rollers (4) arranged at intervals horizontally, so that the beam can freely expand and contract longitudinally after the explosion. The rollers (4) are erected above the concrete piers, and the concrete piers are fixed to the rigid ground. A rigid crossbeam (300) is also connected between the two concrete piers. The rigid crossbeam (300) is fixed to the concrete piers through a steel plate (6). A plurality of displacement sensors (3) are installed at the rigid crossbeam (300) located directly below the beam-type component (100), and are evenly distributed from the position corresponding to the longitudinal center of the beam-type component (100) toward one of the concrete piers. The number of circular steel pipes (7) symmetrically arranged on both sides of the beam-type component (100) in the longitudinal direction is three, and the distance between the axes of two adjacent circular steel pipes (7) in the vertical direction is d; The invention also comprises a calculation and analysis device, which performs the relationship between stress and strain when the circular cross section is subjected to a uniformly distributed load and obtains the longitudinal total restraint force data N and the total resistance bending moment data M, as well as the deflection-time relationship of the beam-type component (100) under the explosion load and the compression membrane effect.

2. The test method of the beam-type component explosion resistance test device based on the squeeze film effect as claimed in claim 1 is characterized in that: Includes steps: S1. Arrange the test device and place explosives at a certain height just above the center of the beam member (100); S2, detonating explosives to apply an explosion load to the upper surface of the beam member (100); S3, collecting the compressive strain data monitored by each resistance strain gauge (2) and the vertical displacement monitored by each displacement sensor (3) at different times when the beam-type component (100) is subjected to the explosion load by means of a data collection and analysis device, so as to combine the data with the known elastic modulus, diameter, length L, Poisson's ratio, loading angle α of the circular steel tube (7) and the distance di between the axis of each circular steel tube (7) and the neutral plane for subsequent calculation and statistical analysis, thereby obtaining the longitudinal total restraint force data N and the total resisting bending moment data M provided by all the circular tie rods for the beam-type component (100) at the different times, thereby obtaining the size of the compression film effect corresponding to the vertical displacement of the beam-type component (100) at different times under the explosion load, and the deflection-time relationship of the beam-type component (100) under the explosion load and the compression film effect; In step S3, the longitudinal total restraint force data N and the total resistance bending moment data M are calculated based on the relationship between stress and strain when the circular cross section is subjected to a uniformly distributed load, specifically: From bottom to top, the longitudinal restraint force provided by each of the two symmetrical circular steel tubes (7) is: The total longitudinal restraint provided by all circular steel tubes (7) is: N=ΣN i Formula (2): From bottom to top, the bending moment resistance provided by each of the two symmetrical circular steel tubes (7) is: M i =Nd i Formula (3); Total moment resistance provided by all circular ties: M=∑M i Formula (4); Substituting formula (1) into formula (2) can obtain the total longitudinal restraint force N provided by all circular steel tubes (7), and substituting formula (3) into formula (4) can obtain the total resistance bending moment M provided by all circular steel tubes (7), where i is 1, 2, 3..., n.

3. The test method according to claim 2, characterized in that: In step S3, the acquisition device acquires a piece of compression strain data detected by the corresponding resistance strain gauge (2) and a piece of vertical displacement data detected by the displacement sensor (3) every 0.001 milliseconds.

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