Reinforced concrete target electromagnetic scattering rapid modeling method and system

Abstract

The invention belongs to the technical field of electromagnetic scattering modeling, and discloses a rapid modeling method and system for electromagnetic scattering of a reinforced concrete target. The modeling process is based on the electromagnetic field Huygens principle and an electromagnetic field high-frequency calculation method, reinforced concrete scattering echoes are obtained through high-frequency electromagnetic scattering mechanism analysis and quantitative calculation in combination with a line antenna radiation model, and the rapid simulation capacity of the electromagnetic scattering characteristics of the reinforced concrete structure is formed. The modeling technology provided by the invention is suitable for a reinforced concrete structure target with any shape, does not limit the embedding mode (the embedding shape can be a net shape or any other embedding shape) of the steel bars in the concrete, and lays a foundation for the research of electromagnetic scattering modeling from a simple structure or a general complex structure to a complex building in the future.

Description

Technical Field

[0001] The invention belongs to the technical field of electromagnetic scattering modeling, and in particular relates to a method and system for rapid electromagnetic scattering modeling of a reinforced concrete target. Background Art

[0002] High-value fixed building targets (such as hangars, bridges and other important buildings) are mostly made of reinforced concrete, and their radar characteristics need to be deeply understood and mastered. In view of the current lack of research reports on such issues at home and abroad, theoretical modeling research on the electromagnetic scattering characteristics of such targets has important theoretical significance and practical engineering application value.

[0003] Buildings constructed of reinforced concrete usually have complex shapes and variable internal reinforcement structures, making radar scattering characteristics modeling extremely challenging.

[0004] The research on the estimation and application of radar target characteristics still faces two challenges. First, most of the above-mentioned electromagnetic scattering characteristic calculation methods are based on numerical calculation methods. The numerical calculation methods of target electromagnetic scattering are often limited by computing resources and cannot effectively calculate the problem of electrically large-sized targets. In many cases, they are even uncalculated. When the target electrical size reaches thousands or even tens of thousands of wavelengths, numerical methods often need to use tens of GB or even TB of memory to complete the calculation. High-frequency asymptotic methods represented by physical optics (PO), physical diffraction theory (PTD), and ray bouncing (SBR) methods have shown obvious advantages in electromagnetic scattering analysis of (super) electrically large and complex targets, large-scale scattering characteristic calculations, real-time (quasi-real-time) scattering characteristic calculations, and the design and optimization of characteristic signal control. For example, they have high computational efficiency, extremely low memory consumption, low requirements for computer simulation hardware, clear physical mechanism explanations, and are easy to perform optimization design and scattering mechanism analysis.

[0005] Secondly, most of the existing electromagnetic scattering models, algorithms and simulation software are based on perfect conductive (PEC) targets. In the context of practical applications, it is urgent to expand the modeling objects to metal and dielectric mixed structure targets. For example, building targets are mostly made of reinforced concrete, and their radar characteristics need to be deeply understood and grasped. Compared with PEC targets, electromagnetic scattering of complex targets containing dielectrics involves more complex electromagnetic scattering mechanisms. Its electromagnetic scattering characteristics are very different from those of PEC targets, and the electromagnetic scattering modeling process is also more complicated. At present, there is a lack of research reports on such issues at home and abroad. Theoretical modeling research on the electromagnetic scattering characteristics of such targets has important theoretical significance and practical engineering application value. Summary of the invention

[0006] The problem solved by the present invention is to provide a rapid modeling method and system for the electromagnetic scattering characteristics of reinforced concrete structure targets. The modeling process is based on the Huygens principle of electromagnetic field and the high-frequency calculation method of electromagnetic field, combined with the wire antenna radiation model, and through the high-frequency electromagnetic scattering mechanism analysis and quantitative calculation, the reinforced concrete scattered echo is obtained to form a rapid simulation capability of the electromagnetic scattering characteristics of the reinforced concrete structure. The modeling technology proposed by the present invention is applicable to reinforced concrete structure targets of any shape, and does not limit the embedding method of the steel bars in the concrete (it can be a mesh or other arbitrary embedding shape), which paves the way for the future upgrade and transformation of electromagnetic scattering modeling from simple structures or general complex structures to complex buildings.

[0007] In order to achieve the above purpose, the present invention adopts the following scheme:

[0008] In a first aspect, the present invention provides a method for rapid modeling of electromagnetic scattering of reinforced concrete targets, comprising the following steps:

[0009] Step 1. Construct a reinforced concrete structure geometric model and select a Huygens surface to enclose the reinforced concrete geometric model;

[0010] Step 2. Decompose the target surface tangential field of the reinforced concrete structure geometric model into three scattering mechanism fields, and perform electromagnetic modeling on the three scattering mechanism fields respectively;

[0011] Step 3. Obtain the scattering contributions of the three scattering mechanism fields respectively;

[0012] Step 4. Perform vector superposition of the scattering contributions of the three scattering mechanism fields to obtain the total scattering field of the reinforced concrete structure.

[0013] Furthermore, in step 1, a Huygens surface is selected to enclose the reinforced concrete geometric model, and the Huygens principle is applied to represent the scattering of the reinforced concrete by a tangential electromagnetic field on the closed surface.

[0014] Furthermore, in step 2, the target surface tangential field is decomposed into: ① the primary scattered field of the outer surface of concrete, ② the field where the penetrating electromagnetic wave is first scattered by the steel bars and then penetrates, and ③ the field where the penetrating electromagnetic wave is first scattered by the inner surface of concrete and then penetrates.

[0015] Furthermore, the calculation method of the scattering contribution of the electromagnetic wave first being scattered by the steel bars and then penetrating the field in step 3 is as follows:

[0016] (1) Ray tracing is performed on the radiation field of the penetrating electromagnetic wave that is first scattered by the steel bars and then penetrates the field, determining the excited area of ​​the steel bars in the reinforced concrete geometric model and calculating the penetration field of the irradiated area;

[0017] (2) The scattered field of the steel bars in the reinforced concrete geometric model is equivalent to the radiation field of the steel bar line source. Based on the excited area of ​​the steel bars in the reinforced concrete geometric model, the radiation field of a certain excited area of ​​the steel bars in the concrete is calculated.

[0018] Furthermore, the method of determining the excited area of ​​the steel bars in the reinforced concrete geometric model is as follows: a finite number of triangular prism beams are used to simulate the penetrating electromagnetic waves in the concrete, the steel bars are regarded as thin cylinders and no longer discretized on the surface, and the excited area on the steel bars is calculated by the geometric intersection determination method of the prism and the thin cylinder.

[0019] Furthermore, the scattering of complex steel structure is decomposed into the superposition of radiation from each small section of steel, and the steel radiation field is constrained to be scattering within the range of the nearby double station angle. The physical optics method is used to give the backscattering contribution of the steel radiation field through the concrete.

[0020] Furthermore, in step 3, the scattering contribution of the primary scattered field of the outer surface of the concrete and the field where the penetrating electromagnetic wave is first scattered by the inner surface of the concrete and then penetrates through the concrete is calculated using geometric optics and physical optics methods.

[0021] In another aspect, the present invention provides a reinforced concrete target electromagnetic scattering rapid modeling system, comprising:

[0022] Module 1, which is used to construct a reinforced concrete structure geometric model and select a Huygens surface to enclose the reinforced concrete geometric model;

[0023] Module 2 is used to decompose the target surface tangential field of the reinforced concrete structure geometric model into three scattering mechanism fields, and perform electromagnetic modeling on the three scattering mechanism fields respectively;

[0024] Module three, which is used to obtain the scattering contributions of three scattering mechanism fields respectively;

[0025] Module 4 is used to vector superimpose the scattering contributions of the three scattering mechanism fields to obtain the total scattering field of the reinforced concrete structure.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] 1. Rapid estimation of electromagnetic scattering characteristics of large reinforced concrete structures (electrical dimensions can be greater than 10,000 times the wavelength) can be achieved on ordinary computers;

[0028] Second, the concrete shape is allowed to be any complex shape, and the internal steel bars can be any non-periodic buried conditions;

[0029] 3. The electromagnetic scattering responses of different mechanisms can be clearly calculated. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0031] Figure 1 This is a flow chart of an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the propagation process of electromagnetic waves in a reinforced concrete structure according to an embodiment of the present invention;

[0033] Figure 3 A schematic diagram of the conversion between the global coordinate system and the local coordinate system according to an embodiment of the present invention;

[0034] Figure 4 Schematic diagram of the relative position of the beam corresponding element and the steel bar in the local coordinate system of the embodiment of the present invention Figure 1 ;

[0035] Figure 5 Schematic diagram of the relative position of the beam corresponding surface element and the steel bar in the local coordinate system of the embodiment of the present invention Figure 2 ;

[0036] Figure 6 This is a schematic diagram of the intersection of the beam and the steel bar in an embodiment of the present invention;

[0037] Figure 7 This is a schematic diagram of a cubic reinforced concrete structure according to an embodiment of the present invention;

[0038] Figure 8 A schematic diagram showing the comparison of scattering fields of different mechanisms of a cubic reinforced concrete structure according to an embodiment of the present invention;

[0039] Fig. 9 Schematic diagram of the total scattered field comparison when different numbers of steel bars are placed in a cubic concrete structure according to an embodiment of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0041] It should be noted that, in the description of the embodiments of the present invention, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "include one..." do not exclude the existence of other identical elements in the process, method, article or device including the elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0042] The terms "first", "second", etc. in this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0043] <Example 1>

[0044] like Figure 1 As shown, this embodiment provides a method for rapid modeling of electromagnetic scattering of reinforced concrete targets, including the following steps:

[0045] Step 1. Construct a reinforced concrete structure geometric model and select a Huygens surface to enclose the reinforced concrete geometric model;

[0046] Step 2. Decompose the target surface tangential field of the reinforced concrete structure geometric model into three scattering mechanism fields, and perform electromagnetic modeling on the three scattering mechanism fields respectively;

[0047] Step 3. Obtain the scattering contributions of the three scattering mechanism fields respectively;

[0048] Step 4. Perform vector superposition of the scattering contributions of the three scattering mechanism fields to obtain the total scattering field of the reinforced concrete structure.

[0049] In step 1 of this embodiment, the outer surface of the reinforced concrete is taken as the Huygens surface.

[0050] like Figure 2As shown in the figure, the tangential field of the target surface is decomposed into: ① the once scattered field of the outer surface of the concrete, ② the field where the penetrating electromagnetic wave is first scattered by the steel bars and then penetrates, and ③ the field where the penetrating electromagnetic wave is first scattered by the inner surface of the concrete and then penetrates. Different high-frequency calculation methods are used to carry out electromagnetic modeling of the fields of these three scattering mechanisms.

[0051] The calculation method for the scattering contribution of the electromagnetic wave that penetrates in step 3, which is first scattered by the steel bars and then penetrates the field, is as follows:

[0052] (1) Ray tracing is performed on the radiation field of the penetrating electromagnetic wave that is first scattered by the steel bars and then penetrates the field, determining the excited area of ​​the steel bars in the reinforced concrete geometric model and calculating the penetration field of the irradiated area;

[0053] (2) The scattered field of the steel bars in the reinforced concrete geometric model is equivalent to the radiation field of the steel bar line source. Based on the excited area of ​​the steel bars in the reinforced concrete geometric model, the radiation field of a certain excited area of ​​the steel bars in the concrete is calculated.

[0054] Among them, ray tracing of the radiation field of the penetrating electromagnetic wave that is first scattered by the steel bars and then penetrates the field includes:

[0055] See also Figure 3 , select the center of the bottom circle of the steel bar as the origin of the local coordinate system xyz coordinates, the axial direction of the steel bar as the z axis, let the direction vector of the transmitted beam be in the xoz plane, and establish a local coordinate system. Convert to the local coordinate system and perform the following judgment steps in the local coordinate system:

[0056] ① Determine whether the x coordinates of the three vertices of the face element are all greater than 0. Figure 4 If the x-coordinates of the three vertices of the triangular facet on the concrete surface corresponding to the beam are all greater than 0, it means that the steel bar is located in front of the propagation direction of the transmitted wave and may be illuminated by the beam, and continue to the next step; otherwise, the steel bar is located behind the propagation direction of the transmitted wave and cannot be illuminated by the transmitted beam.

[0057] ② Determine whether the y coordinates of the three vertices of the face element are not all greater than 0 or less than 0. Figure 5 In the local coordinate system, the straight line where the steel bar axis is located is the z-axis of the coordinate system. When the y coordinates of the three vertices of the surface element are not all greater than 0 or less than 0 (such as Figure 3-5 When the beam intersects the z-axis, it may illuminate the steel bar and make the next judgment; on the contrary, when the y coordinates of the three vertices of the face element are all less than 0 or greater than 0 (such as Figure 3-5 In the case of ΔA′B′C′ and ΔA″B″C″), the beam does not intersect the z-axis and cannot illuminate the steel bars.

[0058] ③Calculate the two intersection points of the beam and the z-axis.

[0059] Calculate the two points E and F on the three sides of ΔABC whose y coordinates are 0. In the order of y coordinates from small to large, assign the x, y, and z coordinates of the three vertices A, B, and C of the triangle to points N1, N2, and N3 respectively. If N2<0, then

[0060]

[0061] Calculate the transmitted wave direction vector in the local coordinate system

[0062]

[0063] Calculate the three-dimensional coordinates of the projection points G and H of points E and F along the wave vector on the z-axis. Figure 6 , the z coordinates of points G(x,y,z) and H(x,y,z) are:

[0064] ④ Determine the excited area on the steel bar surface. For the steel bar length to be H, let m1 = min(G z ,H),m1=max(G z ,H). If m2<0||m1>H, the steel bar cannot be excited by the beam; if m1<0, then in the local coordinate system, the interval in which the steel bar is excited by the beam is a cylinder with point O′(x,y,z)=(0,0,m2 / 2) as the center and height h=m2; if m1>H, then O′(x,y,z)=(0,0,m2 / 2+h / 2) and height h=H-m1; if m1≥0&&m2≤H, then O′(x,y,z)=(0,0,m1 / 2+m2 / 2) and h=m2-m1.

[0065] The calculation of the radiation field of steel bars that can penetrate concrete includes:

[0066] According to the induction theorem, the steel bar surface excites induced current when the ray beam is irradiated, which is the equivalent source of the scattered field. The scattered field of the steel bar structure can be equivalent to the radiation field of the "steel bar line source". The "steel bar line source" model refers to the "wire antenna" model and adds the back propagation constraint corresponding to the back echo received by the radar. From the incremental length diffraction coefficient (ILDC) theory, it can be known that "the scattering field generated by the edge of any shape can be obtained by integrating the irradiated part", that is, each small section is modeled by the so-called "incremental length" method, and the radiation field of the "steel bar line source" of finite length can be obtained by integrating the induced surface current.

[0067] The smaller the target electrical size, the smaller its near field range. When calculating the contribution of the steel bar radiation field penetrating the concrete surface, the concrete surface is finely divided. At this time, each tiny surface element on the concrete surface is located in the far field area of ​​the steel bar radiation field, that is, for any point on a single surface element, the steel bar radiation field is a uniform plane wave, and the field size and phase can be determined by the relative spatial position of the surface element center and the excited area. The radiation field of a certain excited area of ​​steel bars in concrete is:

[0068]

[0069] In the formula, are the horizontally polarized and vertically polarized radiation field components respectively; E0 is the incident electric field amplitude; θ s and are the elevation angle and azimuth angle of the receiving direction respectively; k0 and k c are the wave vector constants in free space and concrete respectively; r is the distance from the origin to the field point; the forms of M and N are as follows:

[0070]

[0071] The contribution of the steel bar radiation field penetrating the concrete surface is calculated by physical optics method. The scattering and penetration-reflection-transmission scattering contribution of the concrete surface are calculated by geometric optics and physical optics methods.

[0072] The total scattered field of the reinforced concrete structure is obtained by superimposing the reinforcement scattering contribution, the concrete surface scattered field and the penetration-reflection-transmission field vector.

[0073] like Figure 7 As shown, the outer side length of the reinforced concrete structure geometric model constructed in this embodiment is 8 meters, with 84 built-in steel bars, each of which is 6 meters long and has a radius of 0.03 meters.

[0074] like Figure 8 As shown, under the conditions of an incident radio frequency of 5 GHz, VV polarization mode, and θ=90°, the reinforced concrete structure constructed in this embodiment has the strongest total backscattering field when the azimuth angles are 0°, ±90°, and ±180°; when the azimuth angles are ±45° and ±135°, the total backscattering field is relatively weak.

[0075] like Fig. 9As shown in the figure, with the increase of the number of built-in steel bars, the contribution of the scattered part after the radiation of the induced current of the steel bars and then passing through the concrete surface becomes larger and larger, and the total field gradually increases accordingly; but at azimuth angles of 0°, ±90°, and ±180°, the propagation direction of the incident electromagnetic wave is perpendicular to the outer surface of the cubic concrete, and the primary scattering field on the outer surface is very strong and dominates the total field. Therefore, the increase in the number of steel bars has no obvious effect on the changes in the total scattered field under these postures, which is consistent with theoretical knowledge.

[0076] This embodiment aims at the geometric characteristics of reinforced concrete structures (concrete piers, bridges, buildings), draws on the traditional ray tracing ideas, and innovatively proposes a set of tracing methods suitable for the penetration ray field inside reinforced concrete structures, which is used to determine the irradiated (or excited) area of ​​the steel bars in the concrete, and calculate the penetration field of the irradiated area. A limited number of triangular prism beams are used to simulate the penetrating electromagnetic waves in the concrete, and the steel bars are regarded as thin cylinders and no longer discretized on the surface. The excited area on the steel bars is calculated by the geometric intersection judgment method of the prism and the thin cylinder, avoiding the heavy triangular face intersection calculation in the traditional ray tracing method. The time complexity of ray tracing in concrete is reduced from M*N to M+m (M is the number of rough divisions of the concrete outer surface, and m is the number of buried steel bars in the concrete), which greatly reduces the time consumption of ray tracing, making the tracing of the radiation ray field of steel bars in concrete efficient and feasible.

[0077] The scattering of complex steel bar structure is properly decomposed into the superposition of radiation of each small section of steel bar, and grid division is no longer performed. Based on the principle of grasping the main scattering contribution of steel bar, the radiation field of steel bar is constrained to be scattering within the range of double station angle near the back. Finally, the physical optics method is used to give the backscattering contribution of the steel bar radiation field through the concrete, so as to realize the calculation of electromagnetic scattering characteristics of electrically small-sized curved surface targets inside the medium.

[0078] The PO method and GO-GO-PO algorithm are used to calculate the primary scattering field and penetration-reflection-transmission field of complex media. Geometric optics is used to determine the ray path on the surface and inside of the medium target, and the physical optics method is used to calculate the contribution of the primary scattering field on the surface and the transmission wave that is transmitted into the medium and then refracted after reflection on the inner surface to the scattering field.

[0079] <Example 2>

[0080] The second embodiment provides a reinforced concrete target electromagnetic scattering rapid modeling system, including:

[0081] Module 1, which is used to construct a reinforced concrete structure geometric model and select a Huygens surface to enclose the reinforced concrete geometric model;

[0082] Module 2 is used to decompose the target surface tangential field of the reinforced concrete structure geometric model into three scattering mechanism fields, and perform electromagnetic modeling on the three scattering mechanism fields respectively;

[0083] Module three, which is used to obtain the scattering contributions of three scattering mechanism fields respectively;

[0084] Module 4 is used to vector superimpose the scattering contributions of the three scattering mechanism fields to obtain the total scattering field of the reinforced concrete structure.

[0085] The specific working process of the units and modules in the above-mentioned system can refer to the corresponding process in the above-mentioned method embodiment, which will not be repeated here. The technicians in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the system is divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit, and the above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of this application.

[0086] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0087] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed in the invention can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0088] In the embodiments provided by the present invention, it should be understood that the disclosed methods and systems can be implemented in other ways. For example, the system embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or modules can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0089] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0090] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0091] If the integrated module / unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the present invention implements all or part of the processes in the above-mentioned embodiment method, and can also be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium. When the computer program is executed by the processor, the steps of the above-mentioned embodiments of the power system transient stability adaptive evaluation method considering the loss of PMU data can be implemented. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may include: any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electric carrier signal, telecommunication signal and software distribution medium.

[0092] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A method for rapid modeling of electromagnetic scattering of reinforced concrete targets, characterized in that: The steps include: Step 1. Construct a reinforced concrete structure geometric model and select a Huygens surface to enclose the reinforced concrete geometric model; Step 2. Decompose the target surface tangential field of the reinforced concrete structure geometric model into three scattering mechanism fields, and perform electromagnetic modeling on the three scattering mechanism fields respectively; Step 3. Obtain the scattering contributions of the three scattering mechanism fields respectively; Step 4. Perform vector superposition of the scattering contributions of the three scattering mechanism fields to obtain the total scattering field of the reinforced concrete structure.

2. The method for rapid electromagnetic scattering modeling of reinforced concrete targets according to claim 1 is characterized in that: In the step 1, a Huygens surface is selected to enclose the reinforced concrete geometric model, and the Huygens principle is applied to represent the scattering of the reinforced concrete with a tangential electromagnetic field on the closed surface.

3. The method for rapid electromagnetic scattering modeling of reinforced concrete targets according to claim 1 is characterized in that: In step 2, the target surface tangential field is decomposed into: ① the primary scattered field of the outer surface of the concrete, ② the field where the penetrating electromagnetic wave is first scattered by the steel bars and then penetrates, and ③ the field where the penetrating electromagnetic wave is first scattered by the inner surface of the concrete and then penetrates.

4. The method for rapid electromagnetic scattering modeling of reinforced concrete targets according to claim 3 is characterized in that: The calculation method of the scattering contribution of the electromagnetic wave that penetrates the field in step 3 is as follows: (1) Ray tracing is performed on the radiation field of the penetrating electromagnetic wave that is first scattered by the steel bars and then penetrates the field, determining the excited area of ​​the steel bars in the reinforced concrete geometric model and calculating the penetration field of the irradiated area; (2) The scattered field of the steel bars in the reinforced concrete geometric model is equivalent to the radiation field of the steel bar line source. Based on the excited area of ​​the steel bars in the reinforced concrete geometric model, the radiation field of a certain excited area of ​​the steel bars in the concrete is calculated.

5. The method for rapid electromagnetic scattering modeling of reinforced concrete targets according to claim 4 is characterized in that: The method for determining the excited area of ​​the steel bars in the reinforced concrete geometric model is specifically as follows: a finite number of triangular prism beams are used to simulate the penetrating electromagnetic waves in the concrete, the steel bars are regarded as thin cylinders and no longer discretized on the surface, and the excited area on the steel bars is calculated by the geometric intersection determination method of the prism and the thin cylinder.

6. The method for rapid electromagnetic scattering modeling of reinforced concrete targets according to claim 4 is characterized in that: The scattering of complex steel structure is decomposed into the superposition of radiation from each small section of steel, and the steel radiation field is constrained to be scattered within the range of the nearby double-station angle in the backward direction. The physical optics method is used to give the backscattering contribution of the steel radiation field penetrating the concrete.

7. The method for rapid electromagnetic scattering modeling of reinforced concrete targets according to claim 4 is characterized in that: In step 3, the scattering contribution of the primary scattered field on the outer surface of the concrete and the field in which the penetrating electromagnetic wave is first scattered by the inner surface of the concrete and then penetrates through the concrete is calculated using geometric optics and physical optics methods.

8. A reinforced concrete target electromagnetic scattering rapid modeling system, characterized in that: include: Module 1, which is used to construct a reinforced concrete structure geometric model and select a Huygens surface to enclose the reinforced concrete geometric model; Module 2 is used to transform the reinforced concrete structure geometry The target surface tangential field of the model is decomposed into three scattering mechanism fields, and electromagnetic modeling is performed on the three scattering mechanism fields respectively; Module three, which is used to obtain the scattering contributions of three scattering mechanism fields respectively; Module 4 is used to vector superimpose the scattering contributions of the three scattering mechanism fields to obtain the total scattering field of the reinforced concrete structure; The reinforced concrete target electromagnetic scattering rapid modeling system is used to execute the steps in the reinforced concrete target electromagnetic scattering rapid modeling method described in any one of claims 1-7.

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