Method and device for analyzing collapse process of reinforced concrete frame structure

Abstract

The invention relates to a reinforced concrete frame structure collapse process analysis method and device, and belongs to the technical field of engineering structure simulation analysis, and the method comprises the steps: building a structure constitutive model according to reinforced concrete frame structure data; the mass of the reinforced concrete frame structure in the structural constitutive model is concentrated to all nodes, and a dynamic model is determined; and based on an explicit gradual integration algorithm, solving the dynamic model to obtain a collapse evaluation index, and based on the collapse evaluation index, analyzing the progressive collapse resistance of the structure. According to the method, the mass is concentrated on all nodes, the iterative convergence problem is avoided, the dynamic model is solved in combination with explicit gradual integration, an equation set does not need to be solved through the iterative process, efficient simulation of the whole collapse process of the reinforced concrete frame structure under various column disassembly working conditions is achieved, and the calculation efficiency is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of engineering structure simulation analysis, and in particular to a method and device for analyzing the collapse process of a reinforced concrete frame structure. Background Art

[0002] As modern building structures continue to expand in size, the threat posed by accidental loads to structural safety is gaining increasing attention. Accidental events such as explosions and impacts can cause localized structural damage, which can then propagate and cause wider-scale structural damage or even complete collapse. This phenomenon, in which localized damage progresses to a structural collapse disproportionate to the initial damage, is defined as progressive collapse. Progressive collapse of building structures is often accompanied by severe casualties and enormous economic losses, potentially triggering social panic and posing a significant threat to public safety and social stability. Numerous major accidents throughout history have demonstrated the serious hazards of progressive collapse. Against this backdrop, researching and improving the progressive collapse resistance of building structures has become a critical and pressing issue in the field of civil engineering. Currently, research on progressive collapse resistance often utilizes the component removal method, also known as the alternate load path method. This method involves removing one or more components from a building structure according to specific principles and methods to simulate initial localized damage under accidental loads. By comparing the load-bearing capacity of the remaining structure, the risk or probability of progressive collapse is assessed.

[0003] In existing technologies, scholars have used the component removal method to study the mechanical mechanisms of progressive collapse. Qian Kai et al. combined experiments and simulations to investigate the collapse resistance of RC beam-slab structures under side column failure, exploring the load and resistance mechanisms. Yi Weijian et al. used the pushdown method to study the collapse resistance of planar RC frame structures, proposed a calculation method based on reliability theory, and analyzed the effect of the number of floors. Xiao Yuzhe et al. conducted static and dynamic tests on reinforced concrete beam-column substructures, revealing the evolution of the force mechanism and dynamic response. Zhou Yun et al. analyzed the force and load transfer paths under central column failure through prefabricated substructure tests. Adam et al. conducted dynamic tests on the bottom corner column of a two-story, two-span RC slab-column structure to evaluate the contributions of the floor slab's bending and hollow mechanisms. Cheng Xiaowei et al. used LS-DYNA software to simulate the dynamic response of frame structures under impact, evaluating the accuracy and efficiency differences between the component removal method and the full-process impact method. Kim et al. used OpenSees software to study the progressive collapse mechanism of planar steel frame structures, comparing the accuracy of linear and nonlinear dynamic analysis methods and identifying weaknesses in collapse-resistant design. Yu Xiaohui et al. used OpenSees to build an RC frame model and analyzed the impact of the catenary mechanism on its collapse-resistant performance.

[0004] Although nonlinear finite element analysis can reveal complex collapse behavior, finite element modeling usually requires iterative solution, which is time-consuming and not suitable for rapid evaluation. In addition, nonlinear static / dynamic analysis often has iterative non-convergence problems due to material and geometric nonlinearities. Summary of the Invention

[0005] In view of this, it is necessary to provide a method and device for analyzing the collapse process of reinforced concrete frame structures to solve the technical problems of time-consuming solution and non-convergence of iteration in the existing technology.

[0006] In order to solve the above problems, in a first aspect, the present invention provides a method for analyzing the collapse process of a reinforced concrete frame structure, comprising: Construct a structural constitutive model based on reinforced concrete frame structure data; The mass of the reinforced concrete frame structure in the structural constitutive model is concentrated at all nodes to determine the dynamic model; The dynamic model is solved based on an explicit step-by-step integration algorithm to obtain a collapse evaluation index, and the ability of the structure to resist progressive collapse is analyzed based on the collapse evaluation index.

[0007] In one possible implementation, a structural constitutive model is constructed based on reinforced concrete frame structure data, including: According to the reinforced concrete frame structure data, the steel bar constitutive model and the concrete constitutive model are constructed; The beam-column components in the reinforced concrete frame structure are divided into several segments along the longitudinal axis. Each segment corresponds to an integration point. The concrete and steel bars are discretized into several fibers at the cross section corresponding to each integration point. Based on the steel bar constitutive model and the concrete constitutive model, the fibers on the cross section are integrated to obtain the cross section resistance and cross section stiffness. The cross section resistance and cross section stiffness corresponding to the integration points on the beam-column components are integrated along the longitudinal axis to obtain the total resistance and total stiffness, and the structural constitutive model is determined.

[0008] In a possible implementation, the concrete constitutive model includes a constrained area concrete constitutive model and a non-constrained area concrete constitutive model.

[0009] In a possible implementation, the steel bar constitutive model adopts the Steel02 model.

[0010] In a possible implementation, the total resistance and total stiffness are calculated and obtained by using a Gauss-Legendre integration algorithm.

[0011] In a possible implementation, a uniaxial nonlinear unit is further added to each node in the dynamic model, and the uniaxial nonlinear unit adopts a uniaxial nonlinear spring model.

[0012] In a possible implementation, the collapse evaluation index is a collapse degree, and the collapse degree is the ratio of the height of the center of gravity of the reinforced concrete frame structure dropped after the components are removed to the original center of gravity height.

[0013] In a second aspect, the present invention further provides a device for analyzing the collapse process of a reinforced concrete frame structure, comprising: The constitutive model construction unit is used to construct a structural constitutive model based on reinforced concrete frame structure data; A dynamic model construction unit concentrates the mass of the reinforced concrete frame structure in the structural constitutive model to all nodes to determine the dynamic model; The collapse simulation solving unit solves the dynamic model based on an explicit step-by-step integration algorithm to obtain a collapse evaluation index, and analyzes the ability of the structure to resist progressive collapse based on the collapse evaluation index.

[0014] In a third aspect, the present invention further provides an electronic device comprising a memory and a processor; The memory is used to store programs; The processor is coupled to the memory and is used to execute the program stored in the memory to implement the steps of the above-mentioned reinforced concrete frame structure collapse process analysis method.

[0015] In a fourth aspect, the present invention further provides a computer-readable storage medium having a program or instruction stored thereon, which, when executed by a processor, implements the steps of the above-mentioned reinforced concrete frame structure collapse process analysis method.

[0016] The beneficial effects of the present invention are as follows: the method for analyzing the collapse process of reinforced concrete frame structures provided by the present invention, by concentrating the mass on all nodes, makes all the degrees of freedom of the reinforced concrete frame structure dynamic degrees of freedom, thereby avoiding the iterative convergence problem. In combination with the explicit step-by-step integration to solve the dynamic model, no iterative process is required to solve the equation group. The displacement of the next time step is explicitly calculated using the motion equation based on the known physical quantities of the current time step and the information of the previous time step, thereby realizing efficient simulation of the entire collapse process of the reinforced concrete frame structure under various column removal conditions, and effectively improving the calculation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic flow chart of an embodiment of the method for analyzing the collapse process of a reinforced concrete frame structure provided by the present invention; Figure 2 For the present invention Figure 1 A schematic flow chart of an embodiment of step S101; Figure 3 Schematic diagram of the constitutive model curve of the restrained area concrete and the constitutive model curve of the unrestrained area concrete provided by the present invention; Figure 4 A schematic diagram of a fiber cross section of a component provided by the present invention; Figure 5 Schematic diagram of the discrete mass model provided by the present invention; Figure 6 Schematic diagram of the uniaxial nonlinear spring model provided by the present invention; Figure 7 A comparison of the final collapse forms of OpenSees and LS-DYNA for the removal of the bottom floor side columns provided by the present invention; Figure 8 A comparison of the final collapse forms of the bottom-level side columns and secondary middle columns provided by the present invention using OpenSees and LS-DYNA; Figure 9 A comparison of the final collapse forms of OpenSees and LS-DYNA for the demolition of the ground floor side columns, secondary middle columns and middle columns provided by the present invention; Figure 10 A schematic structural diagram of an embodiment of the reinforced concrete frame structure collapse process analysis device provided by the present invention; Figure 11 This is a schematic structural diagram of an embodiment of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0018] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of the present invention.

[0019] It should be understood that the schematic drawings are not drawn to scale. The flowcharts used in the present invention illustrate operations implemented according to some embodiments of the present invention. It should be understood that the operations of the flowcharts can be implemented out of sequence, and steps that have no logical contextual relationship can be reversed in order or implemented simultaneously. In addition, those skilled in the art, guided by the content of the present invention, can add one or more other operations to the flowcharts or remove one or more operations from the flowcharts. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different networks and / or processor systems and / or microcontroller systems.

[0020] The terms "first" and "second" in the embodiments of the present invention are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, technical features specified as "first" or "second" may explicitly or implicitly include at least one of these features. "And / or" describes the association between associated objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone.

[0021] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0022] The present invention provides a method and device for analyzing the collapse process of a reinforced concrete frame structure, which are described below.

[0023] Figure 1 A schematic flow chart of an embodiment of the method for analyzing the collapse process of reinforced concrete frame structures provided by the present invention is shown as follows: Figure 1 As shown in Figure 1, the analysis method for the collapse process of reinforced concrete frame structures includes: S101. Construct a structural constitutive model based on reinforced concrete frame structure data; In order to better construct the structural constitutive model, in some embodiments of the present invention, such as Figure 2 As shown, step S101 includes: S201. Constructing a steel bar constitutive model and a concrete constitutive model based on reinforced concrete frame structure data; It should be noted that this application uses OpenSees software for simulation. When undertaking the complex task of simulating actual structures, accurately selecting the appropriate constitutive model is crucial. Based on a variety of factors, including the mechanical properties, load-bearing mode, and operating environment of the specific structure being simulated, the most appropriate steel and concrete constitutive models must be carefully selected from the rich and diverse resources in the OpenSees database. This is by no means a random exercise, as different constitutive models vary significantly in their reflection of the material's true stress-deformation behavior. Choosing the wrong model can lead to simulation results that differ significantly from the actual situation.

[0024] In the process of in-depth research, the key constraint effect of stirrups on concrete is fully considered. In order to improve the simulation accuracy, in some embodiments of the present invention, the concrete is divided into the core concrete of the constraint area and the concrete of the non-constraint area. The concrete constitutive model includes the constrained area concrete constitutive model and the non-constrained area concrete constitutive model, such as Figure 3 As shown in the figure, there are obvious differences between the constitutive model of the core concrete in the constrained area and the constitutive model of the concrete in the unconstrained area, resulting in large differences in their mechanical behaviors when subjected to stress. The steel bar constitutive model adopts the Steel02 model, which is a modified model based on the research results of Menegotto et al. This modified model can incorporate the influence of strain hardening and can reflect the Bauschinger effect. Therefore, the results obtained by simulation using this model are highly consistent with the performance of steel bars in actual repeated loading tests. It should be noted that the steel bar constitutive model is not limited to the Steel02 model. The Steel02 model is selected here based on a comprehensive consideration of accuracy and computational efficiency. When simulating actual situations, the material of the steel bar constitutive model can be replaced.

[0025] S202. Divide the beam-column components in the reinforced concrete frame structure into a plurality of segments along the longitudinal axis, each segment corresponding to an integration point, and discretize the concrete and steel bars into a plurality of fibers at the cross section corresponding to each integration point; It should be noted that in the beam element of the beam-column component, the longitudinal axis is the straight line direction from one end of the beam to the other end, and in the column element, the longitudinal axis is the vertical direction from the top of the column to the bottom of the column; the fiber cross section of the component is as follows: Figure 4 ,When the number of divided fibers is not less than 6, the results of numerical simulation are closer.

[0026] S203. Based on the steel bar constitutive model and the concrete constitutive model, the fibers on the cross section are integrated to obtain the cross section resistance and cross section stiffness. The cross section resistance and cross section stiffness corresponding to the integration points on the beam-column components are integrated along the longitudinal axis to obtain the total resistance and total stiffness, and the structural constitutive model is determined.

[0027] It should be noted that the cross-sectional resistance and cross-sectional stiffness are obtained by integrating the uniaxial constitutive relations of each fiber material under the assumption of a flat cross-section and small deformation; the total resistance and total stiffness are obtained by calculating the resistance and stiffness at each integration point and integrating along the rod length using the Gauss-Legendre integration algorithm. The Gauss-Legendre integration is extremely important in the application of the present invention, as explained below: In the integral interval In, by integral points Constructed interpolation quadrature formula

[0028] Where, and Indicates the longitudinal axis endpoint position of the beam-column structure, represents the integral variable, the integral interval Any position within Indicates location The section resistance or section stiffness at Indicates the number of points. represents the integral weight, represents the location of the integration point, Indicates integral points Section resistance or section stiffness at .

[0029] have Sub-algebraic accuracy is called the Gauss quadrature formula, and the integral point is is the Gauss point, and is then determined as follows according to Legendre's definition:

[0030] Where, represents the polynomial order, express Legendre polynomial of order, Represents a constant.

[0031] After nonlinear transformation, Gauss-Legendre integral formula for two points on an interval

[0032] Where, and Indicates the longitudinal endpoint position of the beam-column structure.

[0033] S102. Concentrate the mass of the reinforced concrete frame structure in the structural constitutive model on all nodes and determine the dynamic model; It should be noted that if Figure 5As shown, conventionally, the mass is concentrated at the end nodes of beams and columns, so that there will be static degrees of freedom. In the solution of structural dynamic response based on static degrees of freedom (such as the Newton-Raphson iteration method for nonlinear static problems), repeated iterations are usually required to approximate the solution. Iterative convergence problems usually occur in the iterative solution process. For example, when solving nonlinear static equilibrium equations, it is necessary to continuously adjust the displacement increment so that the residual force converges to a sufficiently small value. However, this application uses a discrete mass model to concentrate the mass at all nodes, eliminating the static degrees of freedom. The only degree of freedom of the structure is the dynamic degrees of freedom. According to the D'Alembert principle, the equilibrium equation can be listed. The final displacement response of the structure can be obtained by using the explicit step-by-step integration method. In the solution of the structural dynamic response based on dynamic degrees of freedom, there is no such equilibrium iteration process. The motion equation of the dynamic problem is an accurate description of the structural motion in the time domain. As long as the time step is selected appropriately and the coefficient matrix of the motion equation is positive definite, the response of the structure in the entire time history can be solved step by step and stably according to the time step. There will be no situation where the solution cannot be obtained due to non-convergence of the iteration, because it gradually advances the solution in the time history according to the laws of dynamics, rather than relying on iteration to find a solution that meets the equilibrium conditions.

[0034] Considering that the process of complete structural collapse inevitably involves node contact with the ground, in order to better simulate the mechanical behavior of structural collapse and contact with the ground, in some embodiments of the present invention, a uniaxial nonlinear unit is added to each node in the dynamic model. The uniaxial nonlinear unit uses a uniaxial nonlinear spring model to simulate the force and displacement behavior of the node contact with the ground, such as Figure 6 As shown in the figure, when the node does not touch the ground, the internal force of the spring is zero and does not hinder the development of structural displacement. After touching the ground, the internal force of the spring is zero. Rapidly increasing, , Indicates the spring applied position, 、 and Represents a constant, calibrated by experiment.

[0035] S103. Solve the dynamic model based on an explicit step-by-step integration algorithm to obtain a collapse evaluation index, and analyze the ability of the structure to resist progressive collapse based on the collapse evaluation index.

[0036] It should be noted that the explicit step-by-step integration algorithm takes the central difference method as an example. In the central difference method, the displacement The displacement of the first two time steps can be and And the relationship between velocity and acceleration can be directly calculated, the formula is

[0037] Where, represents the position of the next time step, represents the displacement of the current time step, represents the position of the previous time step, represents the time step, represents the diagonal mass matrix, represents the external load, represents the stiffness matrix, represents the damping matrix.

[0038] In some embodiments of the present invention, the collapse evaluation index is the collapse degree, which is the ratio of the height of the center of gravity of the reinforced concrete frame structure after the components are removed to the original center of gravity height. After the components are removed, the greater the collapse degree of the structure, the weaker the ability of the structure to resist progressive collapse. The calculation formula of the collapse degree is:

[0039] Where, Indicates the degree of collapse, Indicates the The quality of the nodes, Indicates the The vertical displacement of the nodes, represents the total mass of all nodes, Indicates the original center of gravity height of the structure.

[0040] In order to verify the effectiveness of the present invention, in a specific embodiment, a frame of an 8-story, 4-span reinforced concrete frame was specifically analyzed, and three working conditions were selected, namely, demolition of the bottom edge, demolition of the bottom side columns and secondary middle columns, and demolition of the bottom side columns, secondary middle columns and middle columns. The whole process of collapse of the reinforced concrete frame structure was simulated and compared based on the OpenSees model and the LS-DYNA model, respectively. Among them, the above-mentioned method of the present application was adopted based on the OpenSees model, and the Alpha-Os integration method in OpenSees was adopted as the optimal explicit step-by-step integration method. The Alpha-OS time integration method performs best in terms of balance accuracy and computational efficiency compared with other integration algorithms. The LS-DYNA model adopts the conventional method in the prior art. The final collapse forms of OpenSees and LS-DYNA with the bottom side columns demolished are compared. Figure 7 As shown in the figure, the final collapse shape of OpenSees and LS-DYNA after removing the side columns and secondary middle columns of the ground floor is compared. Figure 8 As shown in the figure, the final collapse shape of OpenSees and LS-DYNA after removing the side columns, secondary middle columns and middle columns of the ground floor is compared. Figure 9 As shown in Table 1, the calculation time comparison between the OpenSees model and the LS-DYNA model under different working conditions is shown in Table 1: Table 1: Comparison of computational time between the OpenSees model and the LS-DYNA model

[0041] Depend on Figure 7 It can be seen that the OpenSees model's key nodes experience slight vibrations when the structure touches the ground (at a displacement of 3600 mm), resulting in a final stable displacement of 3676 mm. This is because the OpenSees simplified model's ground contact elements utilize extremely stiff nonlinear springs, which begin to provide vertical reaction forces upon contact. During equilibrium, the nodes may displace below the ground and generate vibrations. The LS-DYNA model achieves a final stable displacement of 3279 mm. This is because the lower end of the damaged beam spanning one floor touches the ground during the simulation, and the beam height is 560 mm. The OpenSees model uses a fiber cross-section model and does not consider the cross-sectional shape of the beams and columns. Therefore, the displacements of the key nodes after stabilization differ by the beam height. Otherwise, the two models remain essentially consistent.

[0042] Depend on Figure 8 It can be seen that after the removal of the two columns on one side, most of the concrete of the bottom beam of the first span of the structural model was shattered, and the steel bars were exposed. The concrete at the ends of the beams of each layer in the second span of the structural model was shattered, and the steel bars were exposed to the yield state, which is the main concentrated area of ​​structural damage and deformation. The other two spans did not show obvious damage. Therefore, after the removal of the two columns, only the damaged span was destroyed, and the remaining structure was in a safe state.

[0043] Depend on Figure 9 It can be seen that under conditions where the structural damage is more severe (such as the removal of three columns on the ground floor), there are certain differences in the calculation results of the two models. The calculation results of the OpenSees model show that the structure has undergone directional collapse, while the LS-DYNA model simulates large-scale structural damage, but does not calculate the complete collapse state. Due to the extremely high degree of structural nonlinearity under this condition, the calculation difficulty of the LS-DYNA model increases significantly. Its simulation results may be limited by factors such as the material constitutive model and mesh division, and there is uncertainty in the description of the actual physical process. In contrast, the OpenSees model, through a simplified theoretical modeling method, still has high computational stability and clear theoretical support under highly nonlinear conditions, and can more reasonably describe the structural collapse behavior under complex conditions.

[0044] In summary, the method used in this application has very good timeliness in dismantling components and simulating the entire process of structural collapse.

[0045] Compared with the existing technology, this application concentrates the mass on all nodes so that all degrees of freedom of the reinforced concrete frame structure are dynamic degrees of freedom, thus avoiding the iterative convergence problem. Combined with the explicit step-by-step integration to solve the dynamic model, there is no need for an iterative process to solve the system of equations. The displacement of the next time step is explicitly calculated using the motion equation based on the known physical quantities of the current time step and the information of the previous time step, thereby achieving efficient simulation of the entire collapse process of the reinforced concrete frame structure under various column removal conditions, effectively improving the calculation efficiency.

[0046] In order to better implement a method for analyzing the collapse process of a reinforced concrete frame structure in an embodiment of the present invention, based on a method for analyzing the collapse process of a reinforced concrete frame structure, correspondingly, Figure 10 As shown, an embodiment of the present invention further provides a reinforced concrete frame structure collapse process analysis device 1000, comprising: A constitutive model building unit 1001 is used to build a structural constitutive model based on reinforced concrete frame structure data; The dynamic model construction unit 1002 concentrates the mass of the reinforced concrete frame structure in the structural constitutive model to all nodes and determines the dynamic model; The collapse simulation solving unit 1003 solves the dynamic model based on an explicit step-by-step integration algorithm to obtain a collapse evaluation index, and analyzes the ability of the structure to resist progressive collapse based on the collapse evaluation index.

[0047] The reinforced concrete frame structure collapse process analysis device 1000 provided in the above embodiment can implement the technical solution described in the above embodiment of the reinforced concrete frame structure collapse process analysis method. The specific implementation principles of the above units can refer to the corresponding contents in the above embodiment of the reinforced concrete frame structure collapse process analysis method, which will not be repeated here.

[0048] like Figure 11 As shown, the present invention also provides an electronic device 1100. The electronic device 1100 includes a processor 1101, a memory 1102 and a display 1103. Figure 11 Only some of the components of the electronic device 1100 are shown, but it should be understood that it is not required to implement all of the shown components, and more or fewer components may be implemented instead.

[0049] In some embodiments, the memory 1102 may be an internal storage unit of the electronic device 1100, such as a hard disk or memory of the electronic device 1100. In other embodiments, the memory 1102 may also be an external storage device of the electronic device 1100, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the electronic device 1100.

[0050] Furthermore, the memory 1102 may include both an internal storage unit of the electronic device 1100 and an external storage device. The memory 1102 is used to store application software installed on the electronic device 1100 and various data.

[0051] In some embodiments, the processor 1101 can be a central processing unit (CPU), a microprocessor, or other data processing chip, used to run the program code or process data stored in the memory 1102, such as the reinforced concrete frame structure collapse process analysis method of the present invention.

[0052] In some embodiments, display 1103 can be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, or an OLED (Organic Light-Emitting Diode) touchscreen. Display 1103 is used to display information on electronic device 1100 and to display a visual user interface. Components 1101-1103 of electronic device 1100 communicate with each other via a system bus.

[0053] In some embodiments of the present invention, when the processor 1101 executes the reinforced concrete frame structure collapse process analysis program in the memory 1102, the following steps may be implemented: Construct a structural constitutive model based on reinforced concrete frame structure data; The mass of the reinforced concrete frame structure in the structural constitutive model is concentrated on all nodes to determine the dynamic model; Based on the explicit step-by-step integration algorithm, the dynamic model is solved to obtain the collapse evaluation index, and the ability of the structure to resist progressive collapse is analyzed based on the collapse evaluation index.

[0054] It should be understood that when the processor 1101 executes the reinforced concrete frame structure collapse process analysis program in the memory 1102, in addition to the above functions, it can also implement other functions. For details, please refer to the description of the corresponding method embodiment above.

[0055] Furthermore, the embodiment of the present invention does not specifically limit the type of the electronic device 1100 mentioned. The electronic device 1100 may be a portable electronic device such as a mobile phone, a tablet computer, a personal digital assistant (PDA), a wearable device, a laptop computer, or the like. Exemplary embodiments of portable electronic devices include but are not limited to portable electronic devices equipped with IOS, Android, Microsoft, or other operating systems. The above-mentioned portable electronic devices may also be other portable electronic devices, such as a laptop computer with a touch-sensitive surface (e.g., a touch panel). It should also be understood that in some other embodiments of the present invention, the electronic device 1100 may not be a portable electronic device, but a desktop computer with a touch-sensitive surface (e.g., a touch panel).

[0056] Accordingly, an embodiment of the present invention also provides a computer-readable storage medium, which is used to store computer-readable programs or instructions. When the program or instructions are executed by a processor, the steps or functions of the reinforced concrete frame structure collapse process analysis method provided by the above-mentioned method embodiments can be implemented.

[0057] Those skilled in the art will appreciate that all or part of the process steps of the above-described embodiments can be implemented by instructing related hardware through a computer program, and the above-described program can be stored in a computer-readable storage medium, such as a magnetic disk, an optical disk, a read-only memory, or a random access memory.

[0058] The above is a detailed introduction to the method for analyzing the collapse process of a reinforced concrete frame structure provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

[0059] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with this technical field within the technical scope disclosed in the present invention should be covered by the scope of protection of the present invention.

Claims

1. A method for analyzing the collapse process of reinforced concrete frame structures, characterized in that: include: Construct a structural constitutive model based on reinforced concrete frame structure data; The mass of the reinforced concrete frame structure in the structural constitutive model is concentrated at all nodes to determine the dynamic model; The dynamic model is solved based on an explicit step-by-step integration algorithm to obtain a collapse evaluation index, and the ability of the structure to resist progressive collapse is analyzed based on the collapse evaluation index.

2. The method for analyzing the collapse process of reinforced concrete frame structure according to claim 1, characterized in that: Based on the reinforced concrete frame structure data, a structural constitutive model is constructed, including: According to the reinforced concrete frame structure data, the steel bar constitutive model and the concrete constitutive model are constructed; The beam-column components in the reinforced concrete frame structure are divided into several segments along the longitudinal axis. Each segment corresponds to an integration point. The concrete and steel bars are discretized into several fibers at the cross section corresponding to each integration point. Based on the steel bar constitutive model and the concrete constitutive model, the fibers on the cross section are integrated to obtain the cross section resistance and cross section stiffness. The cross section resistance and cross section stiffness corresponding to the integration points on the beam-column components are integrated along the longitudinal axis to obtain the total resistance and total stiffness, and the structural constitutive model is determined.

3. The method for analyzing the collapse process of reinforced concrete frame structure according to claim 2, characterized in that: The concrete constitutive model includes the constrained area concrete constitutive model and the unconstrained area concrete constitutive model.

4. The method for analyzing the collapse process of reinforced concrete frame structure according to claim 2, characterized in that: The steel bar constitutive model adopts the Steel02 model.

5. The method for analyzing the collapse process of reinforced concrete frame structure according to claim 2, characterized in that: The total resistance and total stiffness are calculated and obtained by using the Gauss-Legendre integration algorithm.

6. The method for analyzing the collapse process of reinforced concrete frame structure according to claim 1, characterized in that: A uniaxial nonlinear unit is further added to each node in the dynamic model, and the uniaxial nonlinear unit adopts a uniaxial nonlinear spring model.

7. The method for analyzing the collapse process of reinforced concrete frame structure according to claim 1, characterized in that: The collapse evaluation index is the collapse degree, which is the ratio of the height of the center of gravity of the reinforced concrete frame structure dropped after the components are removed to the original center of gravity height.

8. A device for analyzing the collapse process of reinforced concrete frame structures, characterized in that: include: The constitutive model construction unit is used to construct a structural constitutive model based on reinforced concrete frame structure data; A dynamic model construction unit concentrates the mass of the reinforced concrete frame structure in the structural constitutive model to all nodes to determine the dynamic model; The collapse simulation solving unit solves the dynamic model based on an explicit step-by-step integration algorithm to obtain a collapse evaluation index, and analyzes the ability of the structure to resist progressive collapse based on the collapse evaluation index.

9. An electronic device, characterized in that: including memory and processor; The memory is used to store programs; The processor is coupled to the memory and is used to execute the program stored in the memory to implement the steps of the reinforced concrete frame structure collapse process analysis method described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that The readable storage medium stores a program or instruction, which, when executed by a processor, implements the steps of the reinforced concrete frame structure collapse process analysis method described in any one of claims 1 to 7.

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