Quantitative representation method of invasive blast wave in double-layer curtain wall space

Abstract

This invention relates to the field of blasting testing technology and discloses a method for quantitatively representing intrusive blasting waves within a double-layer curtain wall space. The method includes establishing an experimental system, creating a basic model of the double-layer curtain wall structure, conducting blasting experiments, verifying the accuracy of the LS-DYNA simulation software's simulation of the experimental content, and parameter analysis. The parameter analysis includes quantitative analysis using blasting wave intensity, intrusion hole height H, and the distance C between the outer and inner curtain walls as variables. Through finite element simulation, combined with extensive data and theoretical analysis, a method for calculating the peak pressure of the intrusive blasting wave inside the structure is derived. This method for quantitatively representing intrusive blasting waves within a double-layer curtain wall space has the advantage of ease of use. It allows for the exploration of the blasting wave pressure inside the structure and the corresponding implementation of structural protection designs, effectively improving the scientific rigor and reference value of internal structural protection designs, and making a significant contribution to the stable management of structural safety.

Description

Technical Field

[0001] This invention relates to the field of blasting test technology, and specifically to a method for quantitatively representing intrusive blasting waves within a double-layered curtain wall space. Background Technology

[0002] In an open space, the pressure-time relationship curve of a blast wave can be obtained through theoretical calculations. However, when a blast wave penetrates into the interior of a space through an opening, the intensity of the blast wave, the size of the opening, and the dimensions of the curtain wall space all affect the pressure inside the structure. In particular, when the blast wave undergoes multiple emission and superposition inside the structure, its pressure expression becomes more complex. Nevertheless, the calculation of the peak value of the blast wave invading the structure has a direct impact on structural protection. Therefore, this invention focuses on the research of a method for calculating the peak value of blast waves inside a structure. Summary of the Invention

[0003] The technical problem to be solved by this invention is to overcome the shortcomings of the existing technology and provide a method for calculating the peak pressure of intrusion blast waves inside a structure by means of finite element simulation, combined with a large amount of data and theoretical analysis. This method effectively improves the scientificity and reference value of the internal protection design of the structure and provides a quantitative representation of intrusion blast waves in a double-layer curtain wall space.

[0004] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0005] A method for quantifying intrusive blast waves within a double-layered curtain wall space includes the following steps:

[0006] (S1) Establish an experimental system, which includes a central explosive, and a concrete structure and a double-layer curtain wall structure set at a radius R from the central explosive. The concrete structure is used to detect the curve relationship between external pressure and time, and the double-layer curtain wall structure is used to detect the curve relationship between internal pressure and time.

[0007] (S2) Establish a basic model of the double-layer curtain wall structure. The basic model includes an inner curtain wall and an outer curtain wall. The outer curtain wall is fixedly connected to the inner curtain wall and faces the central explosive. A first pressure detector is set at the center of the inner curtain wall. The inner curtain wall is a concrete wall with a height of 3 meters and a width of 1 meter. The outer curtain wall is a steel plate with a height of 3 meters and a width of 1 meter. The distance C between the outer curtain wall and the inner curtain wall is 0.225 meters. An intrusion hole with a height H of 0.2 meters and a width of 1 meter is set on the outer curtain wall 0.3 meters from the bottom. The blast wave enters the interior of the double-layer curtain wall structure through the intrusion hole.

[0008] (S3) Conduct a blasting experiment, detonate the central explosive, and obtain the curve relationship between external pressure and time at a distance R from the central explosive through the concrete structure, and obtain the curve relationship between internal pressure and time at a distance R from the central explosive through the double-layer curtain wall structure.

[0009] (S4) Use LS-DYNA simulation software to simulate the experimental content in steps (S1) to (S3), compare the obtained external pressure simulation data and internal pressure simulation data of the curtain wall with the experimental results obtained in step (S3), and verify the correctness of the LS-DYNA simulation software in simulating the experimental content.

[0010] (S5) With other conditions of the double-layer curtain wall structure unchanged, the height of the intrusion hole H is used as a variable. Multiple sets of internal pressure and time curves G(H) of the curtain wall are simulated using LS-DYNA simulation software. Using the multiple sets of internal pressure and time curves G(H) of the curtain wall obtained by simulation, the influence factor Cv corresponding to the height of the intrusion hole H is calculated. The influence factor Cv = the first peak of the internal pressure PsH / the peak of the external pressure Ps.

[0011] (S6) Based on the multiple sets of influencing factors Cv obtained in step (S5), plot the relationship between the intrusion hole height H and the influencing factor Cv, plot G(Cv). The value of the influencing factor Cv1 corresponding to any intrusion hole height Hm can be read from the relationship plot G(Cv). Hbase=0.2 meters is the basic model, and the influencing factor corresponding to the basic model is Cvbase. Define the influencing factor coefficient Cvm=Cv1 / Cvbase corresponding to the intrusion hole height Hm.

[0012] (S7) With other conditions of the double-layer curtain wall structure unchanged, the distance C between the outer curtain wall and the inner curtain wall is used as a variable. Multiple sets of internal pressure and time curves G(C) of the curtain wall are simulated using LS-DYNA simulation software. Using the multiple sets of internal pressure and time curves G(C) of the curtain wall obtained by simulation, the influence factor Cc corresponding to the multiple sets of distance C is calculated. The influence factor Cc = the first peak of the internal pressure of the curtain wall PsC / the peak of the external pressure Ps.

[0013] (S8) Based on the multiple sets of influence factors Cc obtained in step (S7), plot the relationship between the interval C and the influence factor Cc G(Cc). The influence factor Cc1 value corresponding to any interval Cm can be read from the relationship plot G(Cc). Cbase=0.225m is the basic model. The influence factor corresponding to the basic model is Ccbase. Define the influence factor coefficient Ccm=Cc1 / Ccbase corresponding to the interval Cm.

[0014] (S9) With other conditions remaining unchanged for the double-layer curtain wall structure (3), the first peak PsZin of the internal pressure of the curtain wall corresponding to multiple sets of proportional distances Z and the peak PsZout of the external pressure corresponding to multiple sets of proportional distances Z are simulated using LS-DYNA simulation software. The influence factor Cs corresponding to multiple sets of proportional distances Z is calculated. The influence factor Cs = the first peak PsZin of the internal pressure of the curtain wall / the peak PsZout of the external pressure. The calculation formula for the proportional distance Z is as follows:

[0015]

[0016] In the formula, R is the distance from the monitoring point to the central explosive, and W is the equivalent of the central explosive. Note: When the central explosive explodes in free air, W is taken as the equivalent of the central explosive when calculating the proportional distance Z. When the central explosive explodes on the ground, due to the reflection effect of the ground blast wave, W is taken as twice the equivalent of the central explosive when calculating the proportional distance Z.

[0017] (S10) Based on the multiple sets of influence factors Cs obtained in step (S9), plot the relationship graph G(Cs) between the proportional distance Z and the influence factor Cs. The influence factor Csm value corresponding to any proportional distance Zm can be read from the relationship graph G(Cs).

[0018] (S11) For the first peak of the internal pressure of the curtain wall with different intrusion hole heights H, different spacings C, and different proportional distances Z, Psm = Cvm * Ccm * Csm * the peak of the external pressure PsZout;

[0019] (S12) Since they belong to the same explosion source, the slope of the pressure decay inside the curtain wall is consistent with the slope of the pressure decay outside. Plot the decay diagram of the pressure inside the curtain wall after experiencing the first peak Psm. The value of the pressure inside the curtain wall after time Δt can be read from the decay diagram.

[0020] (S13) The first peak Psm of the internal pressure of the curtain wall obtained in step (S11) is superimposed with the value of the pressure attenuation inside the curtain wall obtained in step (S12). Then the maximum pressure peak value Psmax inside the curtain wall is Psm of the first peak Psm of the internal pressure of the curtain wall + value of the pressure attenuation inside the curtain wall Psn.

[0021] As a further explanation of the above technical solution:

[0022] The peak Ps of the external pressure is related to the proportional distance Z in step (S9). The peak Ps of the external pressure can be found in UFC 3-340-02 by the proportional distance Z value, or it can be calculated using CONWEP.

[0023] In step (S1), the concrete structure is a concrete wall that is 3 meters high and 1 meter wide, and a second pressure detector is installed at the center of the concrete structure.

[0024] In step (S5), the height H of the intrusion hole varies from 0.05 meters to 0.8 meters.

[0025] In step (S7), the spacing C varies from 0.225 meters to 1.5 meters.

[0026] In step (S12), time Δt = height of inner curtain wall / explosion wave velocity.

[0027] Compared with the prior art, the advantages of the present invention are as follows:

[0028] The present invention provides a quantitative representation method for intrusive blast waves within a double-layer curtain wall space. This method includes establishing an experimental system, creating a basic model of the double-layer curtain wall structure, conducting blasting experiments, verifying the accuracy of the LS-DYNA simulation software's simulation of the experimental content, and parameter analysis. The parameter analysis includes quantitative analysis using blast wave intensity, intrusion hole height H, and the distance C between the outer and inner curtain walls as variables. Through finite element simulation, combined with extensive data and theoretical analysis, a method for calculating the peak pressure of the intrusive blast wave inside the structure is derived. This method explores the pressure of the blast wave inside the structure and allows for corresponding structural protection design. It has the advantage of ease of use and can effectively improve the scientific nature and reference value of internal structural protection design, making a significant contribution to the stability of structural safety management. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the experimental system.

[0030] Figure 2 This is a schematic diagram of the double-layer curtain wall structure from the side view angle during the experiment.

[0031] Figure 3 This is a schematic diagram of the double-layer curtain wall structure from the frontal view.

[0032] Figure 4 The graph shows the relationship between external and internal pressure and time, based on experimental results and LS-DYNA simulations.

[0033] Figure 5 The graph G(H) shows the relationship between internal pressure and time in the curtain wall for multiple sets of intrusion hole heights H.

[0034] Figure 6 The graph G(Cv) shows the relationship between the intrusion hole height H and the influencing factor Cv.

[0035] Figure 7 G(C) shows the curve relationship between internal pressure and time in the curtain wall corresponding to multiple spacings C.

[0036] Figure 8 The graph G(Cc) shows the relationship between the spacing C and the influence factor Cc.

[0037] Figure 9 The graph G(Cs) shows the relationship between the proportional distance Z and the influence factor Cs.

[0038] Figure 10 This is a comparison chart showing the verification results of the quantization representation method of the present invention.

[0039] Figure 11 This is a graph showing the relationship between various blast wave pressures and proportional distance Z in UFC 3-340-02.

[0040] Legend:

[0041] 1. Central explosive device; 2. Concrete structure; 3. Double-layer curtain wall structure; 301. Inner curtain wall; 302. Outer curtain wall; 303. First pressure detector. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0043] This invention proposes a method for quantifying intrusive blast waves within a double-layer curtain wall space, comprising the following steps:

[0044] (S1) Establish an experimental system, such as Figure 1 As shown, the experimental system includes a central explosive 1, and a concrete structure 2 and a double-layer curtain wall structure 3 positioned at a radius R from the central explosive 1. The concrete structure 2 is used to detect the relationship between external pressure and time, and the double-layer curtain wall structure 3 is used to detect the relationship between internal pressure and time within the curtain wall. Specifically, the central explosive 1, placed on the ground, is 250 kg TNT, and the concrete structure 2 and the double-layer curtain wall structure 3 are positioned at a distance of 52 meters from the 250 kg TNT, i.e., R = 52 meters.

[0045] (S2) Establish the basic model of the double-layer curtain wall structure 3, such as Figure 2 and Figure 3 As shown, the basic model includes an inner curtain wall 301 and an outer curtain wall 302. The outer curtain wall 302 is fixedly connected to the inner curtain wall 301 and faces the central explosive 1. A first pressure detector 303 is installed at the center of the inner curtain wall 301. The inner curtain wall 301 is a concrete wall with a height of 3 meters and a width of 1 meter. The outer curtain wall 302 is a steel plate with a height of 3 meters and a width of 1 meter. The distance C between the outer curtain wall 302 and the inner curtain wall 301 is 0.225 meters. An intrusion hole with a height H of 0.2 meters and a width of 1 meter is provided on the outer curtain wall 302 0.3 meters from the bottom. The blast wave enters the interior of the double-layer curtain wall structure 3 through this intrusion hole.

[0046] (S3) Conduct a blasting experiment, detonate the central explosive 1 (250Kg TNT) placed on the ground, obtain the external pressure versus time curve at a distance of radius R (52 meters) from the central explosive 1 through the concrete structure 2, and obtain the internal pressure versus time curve at a distance of radius R (52 meters) from the central explosive 1 through the double-layer curtain wall structure 3.

[0047] In summary, the basic model of the blasting experiment is as follows: the equivalent W of the central explosive 1 placed on the ground is 250 kg TNT; the distance R from the detection point to the central explosive 1 is 52 meters; the inner curtain wall 301 is a 3-meter-high and 1-meter-wide concrete wall; the outer curtain wall 302 is a 3-meter-high and 1-meter-wide steel plate; the distance C between the outer curtain wall 302 and the inner curtain wall 301 is 0.225 meters; and an intrusion hole with a height H of 0.2 meters and a width of 1 meter is provided on the outer curtain wall 302 at a distance of 0.3 meters from the bottom. The research focuses on the influence of the blast wave intensity, the height H of the intrusion hole, and the distance C between the outer and inner curtain walls on the internal pressure of the curtain wall when the blast wave enters the double-layer curtain wall structure 3 through the intrusion hole. When the above three parameters change, the corresponding coefficients are introduced to transform the different influencing factors into the basic model.

[0048] (S4) Using LS-DYNA simulation software, simulate the experimental content from steps (S1) to (S3). Compare the obtained external pressure simulation data and internal curtain wall pressure simulation data with the basic model experimental results obtained in step (S3) to verify the correctness of the LS-DYNA simulation software's simulation of the experimental content. Specifically, such as... Figure 4 As shown in the left-hand "Comparison of External Explosion Pressure vs. Time Curves" graph, the external pressure versus time curve (red line) simulated by LS-DYNA simulation software matches the external pressure versus time curve (green line) obtained from the experimental test of concrete structure 2. Similarly, in the right-hand "Comparison of Internal Explosion Pressure vs. Time Curves" graph, the internal pressure versus time curve (red line) simulated by LS-DYNA simulation software matches the internal pressure versus time curve (green line) obtained from the experimental test of double-layer curtain wall structure 3. This verifies the correctness of the LS-DYNA simulation software's simulation of this experimental situation. Subsequent parameter analysis will be based on the simulation results of the LS-DYNA simulation software.

[0049] (S5) With other conditions remaining unchanged for the double-layer curtain wall structure 3, and using the intrusion hole height H as a variable, multiple sets of curves G(H) showing the relationship between internal pressure and time in the curtain wall were obtained using LS-DYNA simulation software, such as... Figure 5As shown, using the simulated curves G(H) of multiple sets of internal pressure versus time curves of the curtain wall, the influence factor Cv corresponding to multiple sets of intrusion hole heights H is calculated. This influence factor Cv = the first peak PsH of the internal pressure of the curtain wall / the peak Ps of the external pressure. Specifically, the intrusion hole height H varies from 0.05 meters to 0.8 meters. In one specific embodiment of the invention, the intrusion hole height H takes values ​​of 0.05 meters, 0.1 meters, 0.15 meters, 0.2 meters, 0.3 meters, 0.4 meters, 0.6 meters, and 0.8 meters, respectively. Figure 5 The first peak PsH of the internal pressure of the curtain wall corresponding to the intrusion hole height H of each group can be read from the data. Figure 5 The reflected pressure represents the curve relationship between external pressure and time. Figure 4 The external pressure versus time curve obtained from the LS-DYNA simulation software is consistent, and is placed here... Figure 5 To illustrate the relationship between internal and external pressures of the curtain wall under the variable intrusion hole height H, the peak value Ps of the external pressure is related to the proportional distance Z. The peak value Ps of the external pressure can be found in UFC 3-340-02 using the proportional distance Z value. Figure 11 As shown, or calculated using CONWEP, the formula for calculating the proportional distance Z is as follows:

[0050]

[0051] In the formula, R is the distance from the detection point to the central explosive 1, and W is the equivalent of the central explosive 1. Note: When the central explosive 1 explodes in free air, W is taken as the equivalent value of the central explosive 1 when calculating the proportional distance Z. When the central explosive 1 explodes on the ground, due to the reflection effect of the ground blast wave, W is taken as twice the equivalent value of the central explosive 1 when calculating the proportional distance Z. It should be noted that since the central explosive 1 in steps (S1) to (S3) is placed on the ground, substituting the basic model R = 52 meters and W = (250 * 2) kg TNT into the above formula, we get Z = 6.55 m / kg. 1 / 3 And thus, from Figure 11 The peak value Ps of the external pressure is calculated. It should be noted that in this embodiment, the peak value Ps of the external pressure refers to Z = 6.55 m / Kg. 1 / 3 The corresponding peak value of the external pressure. Figure 5 The values ​​of the first peak PsH of the internal pressure of the curtain wall corresponding to the intrusion hole height H of each group were read from the data, and Z = 6.55 m / Kg. 1 / 3 Substituting the corresponding external pressure peak value Ps into the influence factor Cv = first peak of internal pressure PsH of curtain wall / peak of external pressure Ps, the influence factor Cv corresponding to the intrusion hole height H of each group can be calculated.

[0052] (S6) Based on the multiple sets of influencing factors Cv obtained in step (S5), plot the relationship between the intrusion hole height H and the influencing factor Cv as shown in the figure G(Cv). Figure 6 As shown, the influence factor Cv1 value corresponding to any intrusion hole height Hm can be read from the relationship diagram G(Cv). Hbase = 0.2 meters is the basic model, and the influence factor corresponding to this basic model is Cvbase. The influence factor coefficient Cvm corresponding to the intrusion hole height Hm is defined as Cv1 / Cvbase. Specifically, Figure 6 The x-axis represents the intrusion hole height H, and the y-axis represents the influence factor Cv. The influence factor Cv corresponding to each group of intrusion hole heights H obtained in step (S5) is filled into the table. Figure 6 A graph G(Cv) showing the relationship between the intrusion hole height H and the influencing factor Cv was plotted, using Hbase=0.2 meters as the basic model. Figure 6 If the corresponding Cvbase=0.5393 is read from the data, then the influence factor coefficient Cvm=Cv1 / 0.5393 for any intrusion hole height Hm is determined. Therefore, when the intrusion hole height H changes, the corresponding coefficient Cvm is introduced to transform the influence factor Cv into the basic model.

[0053] (S7) With other conditions of the double-layer curtain wall structure 3 unchanged, and the distance C between the outer curtain wall 302 and the inner curtain wall 301 as the variable, multiple sets of curves G(C) showing the relationship between internal pressure and time in the curtain wall are obtained using LS-DYNA simulation software, such as... Figure 7 As shown, and using the simulated curves G(C) of multiple sets of internal pressure versus time curves of the curtain wall, the influence factor Cc corresponding to multiple sets of spacing C is calculated. This influence factor Cc = the first peak PsC of the internal pressure of the curtain wall / the peak Ps of the external pressure. Specifically, the spacing C varies from 0.225 meters to 1.5 meters. In one specific embodiment of the present invention, the spacing C takes values ​​of 0.225 meters, 0.3 meters, 0.4 meters, 0.5 meters, 0.6 meters, 0.8 meters, 1 meter, and 1.5 meters, respectively. It should be noted that from... Figure 7 As can be seen, when the distance C between the outer curtain wall 302 and the inner curtain wall 301 is greater than 0.6 meters, multi-wave reflection occurs, and the situation is very complex. Therefore, the quantitative analysis of this invention is for the case where the distance C is less than or equal to 0.6 meters. Figure 7 The first peak PsC of the internal pressure of the curtain wall corresponding to each spacing C (less than or equal to 0.6 meters) can be read from the data. Figure 7 The reflected pressure represents the curve relationship between external pressure and time. Figure 4 The external pressure versus time curve obtained from the LS-DYNA simulation software is consistent, and is placed here... Figure 7To illustrate the relationship between internal and external pressures of the curtain wall under a variable spacing C, Z = 6.55 m / kg. 1 / 3 The corresponding external pressure peak Ps can be calculated using existing formulas, which will not be elaborated here. Figure 7 The values ​​of the first peak PsC of the internal pressure of the curtain wall corresponding to each spacing C (less than or equal to 0.6 meters) read from the data, and Z = 6.55 m / kg. 1 / 3 Substituting the corresponding external pressure peak value Ps into the influence factor Cc = first peak of internal pressure PsC / peak of external pressure Ps, the influence factor Cc corresponding to each group of spacing C is calculated.

[0054] (S8) Based on the multiple sets of influence factors Cc obtained in step (S7), plot the relationship between the interval C and the influence factor Cc, G(Cc), as follows. Figure 8 As shown, the influence factor Cc1 value corresponding to any interval Cm can be read from the relationship graph G(Cc). Cbase = 0.225 meters is the basic model, and the influence factor corresponding to this basic model is Ccbase. The influence factor coefficient Ccm corresponding to this interval Cm is defined as Cc1 / Ccbase. Specifically, Figure 8 The x-axis represents the interval C, and the y-axis represents the impact factor Cc. The impact factor Cc corresponding to each interval C obtained in step (S7) is then filled into the table. Figure 8 Plot the relationship between spacing C and influence factor Cc G(Cc), using Cbase = 0.225 meters as the basic model. Figure 8 If the corresponding Ccbase=0.5424 is read from the table, then the influence factor coefficient Ccm=Cc1 / 0.5424 for any interval Cm is determined. Therefore, when the interval C changes, the corresponding coefficient Ccm is introduced to transform the influence factor Cc into the basic model.

[0055] (S9) With other conditions remaining unchanged for the double-layer curtain wall structure (3), the first peak PsZin of the internal pressure of the curtain wall corresponding to multiple sets of proportional distances Z and the peak PsZout of the external pressure corresponding to multiple sets of proportional distances Z are simulated using LS-DYNA simulation software. The influence factor Cs corresponding to multiple sets of proportional distances Z is calculated. The influence factor Cs = the first peak PsZin of the internal pressure of the curtain wall / the peak PsZout of the external pressure. The calculation formula for the proportional distance Z is as follows:

[0056]

[0057] In the formula, R is the distance from the detection point to the central explosive 1, and W is the equivalent of the central explosive 1. Note: When the central explosive 1 explodes in free air, W is taken as the equivalent value of the central explosive 1 when calculating the proportional distance Z. When the central explosive 1 explodes on the ground, due to the reflection effect of the ground blast wave, W is taken as twice the equivalent value of the central explosive 1 when calculating the proportional distance Z. Specifically, substituting R = 52 meters and W = (250 * 2) kg TNT from the basic model in step (S1) into the above formula, we can obtain Z = 6.55 m / kg. 1 / 3 In one specific embodiment of the present invention, the proportional distance Z is taken as 14.11 m / Kg. 1 / 3 11.20m / Kg 1 / 3 8.25m / Kg 1 / 3 6.55m / Kg 1 / 3 5.72m / Kg 1 / 3 5.2m / Kg 1 / 3 and 4.12m / Kg 1 / 3 Using LS-DYNA simulation software, the first peak PsZin of the internal pressure of the curtain wall corresponding to each group of proportional distance Z, and the peak PsZout of the external pressure corresponding to each group of proportional distance Z can be obtained. Substituting the obtained values ​​of the first peak PsZin of the internal pressure of the curtain wall corresponding to each group of proportional distance Z, and the peak PsZout of the external pressure corresponding to each group of proportional distance Z, into the formula Cs = first peak PsZin of the internal pressure of the curtain wall / peak PsZout of the external pressure, the influence factor Cs corresponding to each group of proportional distance Z can be calculated.

[0058] (S10) Based on the multiple sets of influence factors Cs obtained in step (S9), plot the relationship between the proportional distance Z and the influence factors Cs, G(Cs), as follows. Figure 9 As shown, the influence factor Csm value corresponding to any proportional distance Zm can be read from the relationship graph G(Cs). Specifically, Figure 9 The x-axis represents the proportional distance Z, and the y-axis represents the influence factor Cs. The influence factor Cs corresponding to each proportional distance Z obtained in step (S9) is then filled into the table. Figure 9 Plot the relationship between the proportional distance Z and the influence factor Cs, and then draw the graph G(Cs).

[0059] (S11) For different intrusion hole heights H, different spacings C, and different proportional distances Z, the first peak Psm of the internal pressure of the curtain wall is calculated as: Psm = Cvm * Ccm * Csm * the peak of the external pressure PsZout. Specifically, by introducing coefficients Cvm and Ccm, the double-layer curtain wall structures 3 of different sizes are converted into a basic model, i.e., the intrusion hole height H = 0.2 meters, the spacing C between the outer curtain wall 302 and the inner curtain wall 301 is 0.225 meters, and then by introducing coefficients Csm for different detection points to the distance R from the central explosive 1 and the equivalent W of the central explosive 1, the first peak Psm of the internal pressure of the curtain wall for different intrusion hole heights H, the spacing C between the outer curtain wall and the inner curtain wall, and the intensity of the blast wave can be calculated, i.e., the first peak Psm of the internal pressure of the curtain wall is calculated as: Psm = Cvm * Ccm * Csm * the peak of the external pressure PsZout.

[0060] (S12) Since they belong to the same explosion source, the slope of the pressure decay inside the curtain wall is consistent with the slope of the external pressure decay. A decay diagram of the internal pressure after experiencing the first peak Psm is plotted. The pressure value Psn after time Δt can be read from this decay diagram. Specifically, step (S11) only calculated the value of the first peak Psm of the internal pressure. Next, the second peak value of the internal pressure needs to be calculated. An auxiliary diagram needs to be plotted for the second peak value of the internal pressure. Figure 5 and Figure 7 As can be seen, after the first peak Psm is plotted on the pressure versus time curve inside the curtain wall, the slope of the subsequent internal blast wave attenuation is basically the same as that of the external blast wave attenuation. Based on this, an attenuation diagram of the internal blast wave after experiencing the first peak Psm can be drawn. The value of the first peak Psm is plotted according to the slope of the external blast wave attenuation. After a time Δt, the specific value of the internal pressure Psn is obtained, where Δt = (inner curtain wall height 301) / blast wave velocity. It should be noted that the curtain wall height does not affect the peak value of the internal blast wave, but it does affect the length of the blast wave propagation path within the curtain wall, i.e., time Δt = (inner curtain wall height 301) / blast wave velocity.

[0061] (S13) The first peak Psm of the internal pressure of the curtain wall obtained in step (S11) is superimposed with the attenuation value Psn of the internal pressure of the curtain wall obtained in step (S12). Then, the maximum pressure peak value Psmax of the internal pressure of the curtain wall = the first peak Psm of the internal pressure of the curtain wall + the attenuation value Psn of the internal pressure of the curtain wall. Specifically, since the first peak Psm of the internal pressure of the curtain wall returns to the center position (i.e., at the first pressure detector 303) after time Δt, the attenuation value Psn of the internal pressure of the curtain wall plus the value of the first peak Psm of the internal pressure of the curtain wall is the second peak value of the internal pressure of the curtain wall. This second peak is the maximum pressure peak value Psmax of the internal pressure of the curtain wall.

[0062] The following verification of the quantitative representation method of the above-mentioned intrusion blast wave in the double-layer curtain wall space is carried out with a specific model. The specific model is that the equivalent W of the central explosive 1 placed in free air is 400 kg TNT, the distance R from the detection point to the central explosive 1 is 52 meters, the inner curtain wall 301 is a concrete wall with a height of 1.9 meters and a width of 1 meter, the outer curtain wall 302 is a steel plate with a height of 1.9 meters and a width of 1 meter, the distance C between the outer curtain wall 302 and the inner curtain wall 301 is 0.35 meters, and there is an intrusion hole with a height H of 0.25 meters and a width of 1 meter at the bottom of the outer curtain wall 302.

[0063] like Figure 10 As shown, the experimental content of the specific model was first simulated using LS-DYNA simulation software to obtain simulated external pressure data (blue lines in the figure) and simulated internal pressure data of the curtain wall (black lines in the figure). Then, by substituting W=400KgTNT and R=52 meters into the formula, Z=7.058m / Kg was calculated. 1 / 3 ,from Figure 9 The reading is Z = 7.058 m / kg. 1 / 3 The corresponding Csm value; based on the intrusion hole height H=0.25 meters, from Figure 6 Read the Cv1 value corresponding to H=0.25 meters, and then calculate Cvm=Cv1 / 0.5393; based on the spacing C=0.35 meters, from Figure 8 The value of Cc1 corresponding to C=0.35 meters is read from the table, and then Ccm=Cc1 / 0.5424 is calculated; based on Z=7.058m / Kg 1 / 3 ,from Figure 11 The peak value of the external pressure, PsZout, is read from the graph. The first peak value of the internal pressure of the curtain wall in this specific model, Psm, is calculated as Cvm*Ccm*Csm*the peak value of the external pressure, PsZout. The first peak value of the internal pressure, Psm, is plotted according to the slope of the attenuation of the external blast wave. After a time Δt = 1.9 m / blast wave velocity, the attenuation value of the internal pressure, Psn, is obtained. Finally, the maximum pressure peak value of the internal pressure, Psmax, is calculated as the first peak value of the internal pressure, Psm, plus the attenuation value of the internal pressure, Psn, yielding the internal blast wave data obtained through theoretical calculation (red line in the figure). Figure 10 In the experiment, the internal explosion wave data obtained by theoretical calculation (red line in the figure) and the internal pressure simulation data of the curtain wall obtained by LS-DYNA simulation software (black line in the figure) are consistent, thus verifying the correctness of the quantitative representation method of the intrusion explosion wave in the double-layer curtain wall space of the present invention in quantifying this experimental situation.

[0064] This invention provides a quantitative representation method for intrusive blast waves within a double-layer curtain wall space. The method includes establishing an experimental system, creating a basic model of the double-layer curtain wall structure, conducting blasting experiments, verifying the accuracy of the LS-DYNA simulation software's simulation of the experimental content, and parameter analysis. The parameter analysis includes quantitative analysis using blast wave intensity, intrusion hole height H, and the distance C between the outer and inner curtain walls as variables. Through finite element simulation, combined with extensive data and theoretical analysis, a method for calculating the peak pressure of the intrusive blast wave inside the structure is derived. This method explores the pressure of the blast wave inside the structure and allows for corresponding structural protection design. It has the advantage of ease of use and can effectively improve the scientific nature and reference value of internal structural protection design, making a significant contribution to the stability and safety management of structures.

[0065] The above description is merely a preferred embodiment of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. For those skilled in the art, improvements and modifications obtained without departing from the inventive concept should also be considered within the scope of protection of the present invention.

Claims

1. A method for quantitatively representing an intruding blast wave within a double-layered curtain wall space, comprising the following steps: (S1) Establish an experimental system, which includes a central explosive (1), a concrete structure (2) and a double-layer curtain wall structure (3) set at a radius R from the central explosive (1). The concrete structure (2) is used to detect the curve relationship between external pressure and time, and the double-layer curtain wall structure (3) is used to detect the curve relationship between internal pressure and time. (S2) Establish a basic model of the double-layer curtain wall structure (3). The basic model includes an inner curtain wall (301) and an outer curtain wall (302). The outer curtain wall (302) is fixedly connected to the inner curtain wall (301) and faces the central explosive (1). A first pressure detector (303) is set at the center of the inner curtain wall (301). The inner curtain wall (301) is a concrete wall with a height of 3 meters and a width of 1 meter. The outer curtain wall (302) is a steel plate with a height of 3 meters and a width of 1 meter. The distance C between the outer curtain wall (302) and the inner curtain wall (301) is 0.225 meters. An intrusion hole with a height H of 0.2 meters and a width of 1 meter is provided on the outer curtain wall (302) 0.3 meters from the bottom. The blast wave enters the interior of the double-layer curtain wall structure (3) through the intrusion hole. (S3) Conduct a blasting experiment, detonate the central explosive (1), obtain the curve relationship between external pressure and time at a radius R from the central explosive (1) through the concrete structure (2), and obtain the curve relationship between internal pressure and time of the curtain wall at a radius R from the central explosive (1) through the double-layer curtain wall structure (3). (S4) Use LS-DYNA simulation software to simulate the experimental content in steps (S1) to (S3), compare the obtained external pressure simulation data and internal pressure simulation data of the curtain wall with the experimental results obtained in step (S3), and verify the correctness of the LS-DYNA simulation software in simulating the experimental content. (S5) With other conditions unchanged, the height of the intrusion hole H is used as a variable. Multiple sets of internal pressure and time curves G(H) of the curtain wall are simulated using LS-DYNA simulation software. The influence factor Cv corresponding to the height of the intrusion hole H is calculated using the multiple sets of internal pressure and time curves G(H) of the curtain wall obtained by simulation. The influence factor Cv = the first peak of the internal pressure PsH / the peak of the external pressure Ps. (S6) Based on the multiple sets of influencing factors Cv obtained in step (S5), plot the relationship between the intrusion hole height H and the influencing factor Cv, plot G(Cv). The value of the influencing factor Cv1 corresponding to any intrusion hole height Hm can be read from the relationship plot G(Cv). Hbase=0.2 meters is the basic model, and the influencing factor corresponding to the basic model is Cvbase. Define the influencing factor coefficient Cvm=Cv1 / Cvbase corresponding to the intrusion hole height Hm. (S7) With other conditions of the double-layer curtain wall structure (3) unchanged, the distance C between the outer curtain wall (302) and the inner curtain wall (301) is used as a variable. Multiple sets of internal pressure and time curves G(C) of the curtain wall are simulated using LS-DYNA simulation software. The influence factor Cc corresponding to the multiple sets of internal pressure and time curves G(C) of the curtain wall are calculated using the simulated multiple sets of internal pressure and time curves G(C). The influence factor Cc = the first peak PsC of the internal pressure of the curtain wall / the peak Ps of the external pressure. (S8) Based on the multiple sets of influence factors Cc obtained in step (S7), plot the relationship between the interval C and the influence factor Cc G(Cc). The influence factor Cc1 value corresponding to any interval Cm can be read from the relationship plot G(Cc). Cbase=0.225m is the basic model. The influence factor corresponding to the basic model is Ccbase. Define the influence factor coefficient Ccm=Cc1 / Ccbase corresponding to the interval Cm. (S9) With other conditions remaining unchanged for the double-layer curtain wall structure (3), the first peak PsZin of the internal pressure of the curtain wall corresponding to multiple sets of proportional distances Z and the peak PsZout of the external pressure corresponding to multiple sets of proportional distances Z are simulated using LS-DYNA simulation software. The influence factor Cs corresponding to multiple sets of proportional distances Z is calculated. The influence factor Cs = the first peak PsZin of the internal pressure of the curtain wall / the peak PsZout of the external pressure. The calculation formula for the proportional distance Z is as follows: In the formula, R is the distance from the detection point to the central explosive (1), and W is the equivalent of the central explosive (1). Note: When the central explosive (1) explodes in free air, W is taken as the equivalent of the central explosive (1) when calculating the proportional distance Z. When the central explosive (1) explodes on the ground, due to the reflection effect of the ground blast wave, W is taken as twice the equivalent of the central explosive (1) when calculating the proportional distance Z. (S10) Based on the multiple sets of influence factors Cs obtained in step (S9), plot the relationship graph G(Cs) between the proportional distance Z and the influence factor Cs. The influence factor Csm value corresponding to any proportional distance Zm can be read from the relationship graph G(Cs). (S11) For the first peak of the internal pressure of the curtain wall with different intrusion hole heights H, different spacings C, and different proportional distances Z, Psm = Cvm * Ccm * Csm * the peak of the external pressure PsZout; (S12) Since they belong to the same explosion source, the slope of the pressure decay inside the curtain wall is consistent with the slope of the pressure decay outside. Plot the decay diagram of the pressure inside the curtain wall after experiencing the first peak Psm. The value of the pressure inside the curtain wall after time Δt can be read from the decay diagram. (S13) The first peak Psm of the internal pressure of the curtain wall obtained in step (S11) is superimposed with the value of the pressure attenuation inside the curtain wall obtained in step (S12). Then the maximum pressure peak value Psmax inside the curtain wall is Psm of the first peak Psm of the internal pressure of the curtain wall + value of the pressure attenuation inside the curtain wall Psn.

2. The method for quantifying intrusive blast waves in a double-layer curtain wall space according to claim 1, characterized in that, The peak Ps of the external pressure is related to the proportional distance Z in step (S9). The peak Ps of the external pressure can be found in UFC 3-340-02 by the proportional distance Z value, or it can be calculated using CONWEP.

3. The method for quantifying intrusive blast waves in a double-layer curtain wall space according to claim 1, characterized in that, In step (S1), the concrete structure (2) is a concrete wall that is 3 meters high and 1 meter wide, and a second pressure detector is installed at the center of the concrete structure (2).

4. The method for quantifying intrusive blast waves in a double-layer curtain wall space according to claim 1, characterized in that, In step (S5), the height H of the intrusion hole varies from 0.05 meters to 0.8 meters.

5. The method for quantifying intrusive blast waves in a double-layer curtain wall space according to claim 1, characterized in that, In step (S7), the spacing C varies from 0.225 meters to 1.5 meters.

6. The method for quantifying intrusive blast waves in a double-layer curtain wall space according to claim 1, characterized in that, In step (S12), time Δt = height of inner curtain wall (301) / explosion wave velocity.

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