CN114862087A - Generalized interpolation object particle method-based subway tunnel explosion accident hazard evaluation method - Google Patents
Generalized interpolation object particle method-based subway tunnel explosion accident hazard evaluation method Download PDFInfo
- Publication number
- CN114862087A CN114862087A CN202210195662.3A CN202210195662A CN114862087A CN 114862087 A CN114862087 A CN 114862087A CN 202210195662 A CN202210195662 A CN 202210195662A CN 114862087 A CN114862087 A CN 114862087A
- Authority
- CN
- China
- Prior art keywords
- explosion
- model
- subway tunnel
- explosion accident
- calculation
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000004880 explosion Methods 0.000 title claims abstract description 76
- 238000000034 method Methods 0.000 title claims abstract description 67
- 238000011156 evaluation Methods 0.000 title claims abstract description 13
- 239000002245 particle Substances 0.000 title claims description 37
- 239000000463 material Substances 0.000 claims abstract description 85
- 230000006378 damage Effects 0.000 claims abstract description 54
- 238000004364 calculation method Methods 0.000 claims abstract description 35
- 208000027418 Wounds and injury Diseases 0.000 claims abstract description 28
- 208000014674 injury Diseases 0.000 claims abstract description 28
- 230000004044 response Effects 0.000 claims abstract description 21
- 238000004088 simulation Methods 0.000 claims abstract description 20
- 239000002689 soil Substances 0.000 claims abstract description 18
- 239000004567 concrete Substances 0.000 claims description 37
- 239000002360 explosive Substances 0.000 claims description 27
- 238000005192 partition Methods 0.000 claims description 23
- 238000005474 detonation Methods 0.000 claims description 15
- 238000004422 calculation algorithm Methods 0.000 claims description 14
- 238000006073 displacement reaction Methods 0.000 claims description 10
- 239000011435 rock Substances 0.000 claims description 10
- 229910000831 Steel Inorganic materials 0.000 claims description 6
- 230000008859 change Effects 0.000 claims description 6
- 239000010959 steel Substances 0.000 claims description 6
- 238000010586 diagram Methods 0.000 claims description 5
- 238000013507 mapping Methods 0.000 claims description 5
- 230000008569 process Effects 0.000 claims description 2
- 230000009471 action Effects 0.000 abstract description 7
- 230000000694 effects Effects 0.000 abstract description 5
- 238000009472 formulation Methods 0.000 abstract description 4
- 239000000203 mixture Substances 0.000 abstract description 4
- 238000011084 recovery Methods 0.000 abstract description 3
- 230000008439 repair process Effects 0.000 abstract description 3
- 230000007547 defect Effects 0.000 abstract description 2
- 238000011158 quantitative evaluation Methods 0.000 abstract description 2
- 238000005056 compaction Methods 0.000 description 6
- 229910001294 Reinforcing steel Inorganic materials 0.000 description 4
- 230000010354 integration Effects 0.000 description 4
- 238000005728 strengthening Methods 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 238000005482 strain hardening Methods 0.000 description 3
- 230000007704 transition Effects 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 239000011381 foam concrete Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000012546 transfer Methods 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q10/00—Administration; Management
- G06Q10/06—Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling
- G06Q10/063—Operations research, analysis or management
- G06Q10/0635—Risk analysis of enterprise or organisation activities
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06Q—INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR
- G06Q50/00—Information and communication technology [ICT] specially adapted for implementation of business processes of specific business sectors, e.g. utilities or tourism
- G06Q50/10—Services
- G06Q50/26—Government or public services
- G06Q50/265—Personal security, identity or safety
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06T—IMAGE DATA PROCESSING OR GENERATION, IN GENERAL
- G06T17/00—Three dimensional [3D] modelling, e.g. data description of 3D objects
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F2119/00—Details relating to the type or aim of the analysis or the optimisation
- G06F2119/14—Force analysis or force optimisation, e.g. static or dynamic forces
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T90/00—Enabling technologies or technologies with a potential or indirect contribution to GHG emissions mitigation
Landscapes
- Engineering & Computer Science (AREA)
- Business, Economics & Management (AREA)
- Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- Human Resources & Organizations (AREA)
- General Physics & Mathematics (AREA)
- Economics (AREA)
- Tourism & Hospitality (AREA)
- Strategic Management (AREA)
- Entrepreneurship & Innovation (AREA)
- Geometry (AREA)
- Marketing (AREA)
- Educational Administration (AREA)
- Development Economics (AREA)
- General Business, Economics & Management (AREA)
- Game Theory and Decision Science (AREA)
- Quality & Reliability (AREA)
- Computer Security & Cryptography (AREA)
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Primary Health Care (AREA)
- Computer Graphics (AREA)
- Operations Research (AREA)
- Software Systems (AREA)
- Computer Hardware Design (AREA)
- Evolutionary Computation (AREA)
- General Engineering & Computer Science (AREA)
- Management, Administration, Business Operations System, And Electronic Commerce (AREA)
Abstract
The invention provides a method for evaluating the hazard of an explosion accident of a subway tunnel based on a generalized interpolation material point method. The method utilizes a generalized interpolation material dot method to carry out explicit dynamic solution on a three-dimensional model of a subway tunnel structure and surrounding rock-soil bodies under the action of explosion. And finally, quantitatively calculating the model response under the explosion action, and obtaining the subareas of the personnel injury grade and the structure injury grade according to the overpressure calculation result and the injury factor calculation result, thereby quantitatively evaluating the hazard of the explosion accident. The method makes up the defects of the traditional experience-based qualitative evaluation, overcomes the numerical difficulty of the traditional finite element simulation method caused by grid distortion during explosion simulation, provides a set of feasible quantitative evaluation method for harmfulness, has a certain practical application value, has a positive propulsion effect on the formulation of a special emergency plan, and has a guiding significance on post-disaster first-aid repair and later-stage recovery work.
Description
Technical Field
The invention relates to the technical field of hazard evaluation, in particular to a method for evaluating hazard of an explosion accident of a subway tunnel based on a generalized interpolation material point method.
Background
The development of underground space and the construction of subway tunnels are one of the basic tasks in the development and construction of modern cities, and the problems of large city environment protection, traffic jam and the like can be effectively relieved by means of the development of the subway tunnels.
However, subway tunnels have the characteristics of dense pipelines, closed space, high personnel density and the like, and once safety accidents such as explosion occur, great harm is generated to personnel safety and social order. At present, a complete subway tunnel explosion disaster emergency treatment plan is not established in China, and the emergency plan is made by mainly taking the management measures of strengthening safety inspection, explosive investigation, accelerating anti-terrorism emergency response speed and the like by taking the reference of foreign experiences.
When an explosion accident occurs, due to different subway tunnel structures, the response rule is very complex, and the damage of the explosion to structural facilities and internal personnel is difficult to be qualitatively measured only by experience. However, the existing theoretical or numerical method cannot solve the complex problem of ultra-high speed and large deformation caused by explosion well.
Therefore, the method suitable for evaluating the hazard of the subway tunnel explosion accident is established, has a positive propulsion effect on the formulation of a special emergency plan, and has guiding significance on post-disaster rush repair and later recovery work.
Disclosure of Invention
The invention aims to provide a method for evaluating the hazard of an explosion accident of a subway tunnel based on a generalized interpolation material point method, which aims to solve the problems in the prior art.
The technical scheme adopted for achieving the purpose of the invention is that the method for evaluating the hazard of the explosion accident of the subway tunnel based on the generalized interpolation material point method comprises the following steps:
1) and constructing an engineering physical model according to the engineering structural characteristics. The engineering physical model comprises a structural model of the subway tunnel and a geological model of surrounding rock and soil masses. Discretizing a continuum of an engineering physics model to N p Each of the material points is assigned a corresponding material parameter. And covering the whole calculation domain by adopting a uniform structural grid to generate a background grid.
2) And setting the time step length of each step of calculation according to the initial condition, the boundary condition and the load condition of the engineering physical model.
3) Setting the position of the detonation point according to the actual situation, and calculating the equivalent weight of the explosive according to the type and the volume of the explosive.
4) And solving the explosion response by using a material dot method.
5) Drawing an overpressure distribution cloud chart according to the explosion response; and (5) drawing a personnel injury grade partition map according to personnel injury grade division standards.
6) And drawing a damage factor cloud picture according to the explosion response. And drawing a structural damage grade partition diagram according to the structural damage grade division standard.
7) And carrying out comprehensive explosion accident hazard evaluation according to the personnel injury grade partition map and the structural injury grade partition map.
Further, in step 4), the calculation process of the explosion response at a single time step is as follows: and mapping the material point information and the external force to the background grid nodes. And (4) carrying out display integration solution on the model by using a generalized interpolator particle method containing a contact algorithm. And after the calculation is finished, outputting the overpressure value and wavefront distribution of each air matter particle, outputting the stress value, displacement value and plastic strain value of each concrete matter particle, and outputting the stress value, displacement value and plastic strain value of each rock matter particle. And remapping the calculation result on each material point to the background grid node. And (4) obtaining a distribution cloud picture of each calculation result by adopting an interpolation algorithm on the nodes. And judging whether the time to the end point is calculated or not, if not, switching to the next time step, and if so, ending.
Further, in the step 4), the subway tunnel structure part adopts HJC concrete model. The concrete structure internal reinforcing steel bars are dispersed into rod units by adopting a hybrid particle method. The rod unit nodes move together with the concrete material points. The constitutive model of the rod unit node adopts an ideal elastic-plastic model.
Further, after the step 7), the method also comprises the steps of changing the equivalent weight of different explosives, the positions of explosion points, the structural forms and the material parameters, repeating the steps, and analyzing the change rule of the explosion accident risk in different scenes according to different simulation results.
The technical effects of the invention are undoubted:
A. the generalized interpolation material point simulation method is utilized to overcome the problem that the traditional finite element simulation method is difficult to generate numerical values due to grid distortion during explosion simulation, and the problems of ultra-high speed and large deformation of explosion can be better solved;
B. the HJC model is utilized to better solve the impact problem of the concrete structure under the action of explosion, and the important function of the steel bar in the structure is considered by utilizing the hybrid particle method;
C. the transfer characteristics of the explosive stress wave among different object interfaces are better reflected by utilizing a material point contact algorithm;
D. according to the quantitative numerical simulation result, a personnel injury grade partition map and a structure injury grade partition map can be obtained, so that comprehensive hazard evaluation is further performed on the explosion accident, and the formulation of a special emergency plan can be better guided;
E. the equivalent weight of explosive, the position of an explosion point, the structural form, the material parameters and the like can be adjusted at will in the model, so that the change rule of the explosion accident risk under different scenes can be conveniently analyzed according to different simulation results.
Drawings
FIG. 1 is a flow chart of an implementation method;
FIG. 2 is a three-dimensional structure model constructed at a subway station according to example 7;
FIG. 3 is a cloud diagram of the peak overpressure distribution calculated by simulation of a subway station in example 7;
FIG. 4 is a plot of the injury level of the personnel calculated by the simulation of the subway platform in example 7;
fig. 5 is a cloud view (top view) of the distribution of the damage factors of the concrete floor calculated by simulation of the subway platform in example 7;
FIG. 6 is a sectional view (top view) of the damage level of the concrete floor calculated by the simulation of the subway platform according to example 7;
FIG. 7 is a cloud view (cross-sectional view) of the distribution of the damage factors of the concrete floor calculated by simulation at a subway station platform according to example 7;
fig. 8 is a sectional view (cross-sectional view) of the damage level of the concrete floor calculated by the simulation of the subway station according to example 7.
Detailed Description
The present invention is further illustrated by the following examples, but it should not be construed that the scope of the above-described subject matter is limited to the following examples. Various substitutions and alterations can be made without departing from the technical idea of the invention and the scope of the invention is covered by the present invention according to the common technical knowledge and the conventional means in the field.
Example 1:
referring to fig. 1, the embodiment discloses a method for evaluating the hazard of an explosion accident of a subway tunnel based on a generalized interpolation material point method, which comprises the following steps:
1) and constructing an engineering physical model according to the engineering structural characteristics. The engineering physical model comprises a structural model of a subway tunnelAnd geological models of surrounding rock-soil masses. Discretizing a continuum of an engineering physics model to N p Each of the material points is assigned a corresponding material parameter. And covering the whole calculation domain by adopting a uniform structural grid to generate a background grid.
2) And setting the initial condition, the boundary condition and the load condition of the engineering physical model, and setting the time step length of each step of calculation.
3) Setting the position of the detonation point according to the actual situation, and calculating the equivalent weight of the explosive according to the type and the volume of the explosive.
4) And solving the explosion response by using a material dot method.
5) Drawing an overpressure distribution cloud chart according to the explosion response; and (5) drawing a personnel injury grade partition map according to personnel injury grade division standards.
6) And drawing a damage factor cloud picture according to the explosion response. And drawing a structural damage grade partition diagram according to the structural damage grade division standard.
7) And carrying out comprehensive explosion accident hazard evaluation according to the personnel injury grade partition map and the structural injury grade partition map.
The physical Point Method (MPM) as a meshless algorithm has the advantages of no mesh distortion, no convection term in a control equation, and the like. The embodiment provides an effective way for researching the evaluation method problem of the harmfulness of the subway tunnel explosion accident.
Example 2:
the main steps of the embodiment are the same as those of embodiment 1, wherein, in step 4), the three-dimensional models of the infrastructure structure and the surrounding rock-soil mass are subjected to explicit dynamic solution under the action of explosion by using a generalized interpolation material dot method.
The explosion response calculation flow of a single time step is as follows: and mapping the material point information and the external force to the background grid nodes. And (3) carrying out display integration solution on the model by using a generalized interpolator particle method containing a contact algorithm. And after the calculation is finished, outputting the overpressure value and wavefront distribution of each air matter particle, outputting the stress value, displacement value and plastic strain value of each concrete matter particle, and outputting the stress value, displacement value and plastic strain value of each rock matter particle. And remapping the calculation result on each material point to the background grid node. And (4) obtaining a distribution cloud picture of each calculation result by adopting an interpolation algorithm on the nodes. And judging whether the time to the end point is calculated or not, if not, switching to the next time step, and if so, ending.
Example 3:
the main steps of this embodiment are the same as those of embodiment 1, wherein, in step 4), the subway tunnel structure portion adopts HJC concrete model, and the equation of state of HJC concrete model is shown in formulas (8) to (10):
elastic phase p ═ K elastic μ (8)
Transition phase
Compaction phase
Wherein p is the concrete ball stress, K elastic Is the elastic volume modulus, mu is the elastic volume strain,
is plastic volume strain, F is compaction factor, K 1 ，K 2 ，K 3 Are all material parameters. In this example, K 1 The values are as follows: 85GPa, K 2 The values are as follows: 171GPa, K 3 The values are as follows: 208 GPa.
The concrete structure internal reinforcing steel bars are dispersed into rod units by adopting a hybrid particle method. The rod unit nodes move together with the concrete material points. The constitutive model of the rod unit node adopts an ideal elastic-plastic model. The material model of the steel bar is shown as the formula (11):
in the formula, σ y To yield stress,. epsilon p In order to be equivalent to the plastic strain,
is a dimensionless equivalent plastic strain rate, A is a reference strain rate and an initial yield stress at a reference temperature, B is a material strain hardening modulus, n is a hardening parameter, C is a material strain rate strengthening parameter, m is a softening parameter of the material, and T is a softening parameter of the material * Is a dimensionless temperature.
The surrounding rock-soil mass adopts a DP constitutive model, and the yield function of the model is shown as the formula (12):
wherein f is the yield function, I 1 Is a first constant of stress, J 2 And is a second bias stress invariant, and alpha and k are normal numbers. In this embodiment, α is 0.134, and k is 11.11.
The state equation adopted by explosive explosion is shown as formula (13):
wherein p is the pressure of the detonation products, E is the internal energy per unit initial volume of the detonation products, V is the volume of the detonation products, A, B, R 1 、R 2 And ω is a user-defined material parameter. In this embodiment, the value of A is 371.2GPa, the value of B is 3.23GPa, and R 1 A value of 4.15, R 2 A value of 0.95 and omega of 0.30
Air is expressed by the equation of state of a linear polynomial as in equation (14):
p＝c 0 +c 1 μ+c 2 μ 2 +c 3 μ 3 +(c 4 +c 5 μ+c 6 μ 2 )E (14)
wherein p is pressure, c 0 ～c 6 For custom material constants, μ is the air volume strain and E is the internal energy per unit volume of air. In this example, c 0 ～c 6 The values are as follows in sequence: 0. 0,0.4 and 0.
Example 4:
the main steps of this embodiment are the same as embodiment 1, wherein, after step 7), the method further comprises the steps of changing the equivalent weight of different explosives, the position of an explosion point, the structural form and the material parameters, repeating the steps, and analyzing the change rule of the explosion accident risk in different scenes according to different simulation results.
Example 5:
the main steps of this embodiment are the same as those of embodiment 1, wherein a generalized interpolation particle method is used to perform explicit dynamic solution under the explosion effect on a three-dimensional model of an infrastructure structure and surrounding rock-soil mass, and the shape function derivative of the generalized interpolation particle method are shown in formulas (15) to (16):
wherein L is the length of the grid, 2L p Is the particle length, x p Are the coordinates of the particles. x is the number of I Are the coordinates of the nodes.
Example 6:
the method for evaluating the hazard of the explosion accident of the subway tunnel based on the generalized interpolation material point method comprises the following steps:
1) and constructing an engineering physical model according to the engineering structural characteristics. The engineering physical model comprises a structural model of the subway tunnel and a geological model of surrounding rock and soil masses. Discretizing a continuum of an engineering physics model to N p And obtaining a group of three-dimensional lattice coordinates by the object points. Each material point is assigned a corresponding material parameter. Behind the material points a layer of computational mesh is arranged. The density of the material point and background grid arrangement can affect the accuracy of the calculated results.
2) The initial conditions, boundary conditions (fixed boundary, non-reflection boundary, etc.) and loading conditions (buildings on top of the facility, personnel loads, etc.) of the engineering physical model are given, and the time step length of each step of calculation is set. The time step of each calculation is required to be smaller than the maximum critical step so as to ensure the convergence of the calculation.
3) Setting the position of the detonation point according to the actual situation, and calculating the equivalent weight of the explosive according to the type and the volume of the explosive. And (4) dividing the total internal energy of the explosive by the energy released by the TNT explosion of unit mass to calculate the equivalent of the explosive.
4) And solving the explosion response by using a particle method. And (3) carrying out explicit dynamic solution on the three-dimensional models of the infrastructure structure and the surrounding rock-soil mass under the action of explosion by utilizing a generalized interpolation material particle method. The concrete adopts an HJC model, the steel bars adopt a rod unit model, the rock-soil body adopts a DP model, the explosive adopts a JWL explosion model, and meanwhile, the contact between air and the concrete structure and the rock-soil body is considered.
The explosion response calculation flow of a single time step is as follows: and mapping the material point information and the external force to the background grid nodes. And (4) carrying out display integration solution on the model by using a generalized interpolator particle method containing a contact algorithm. And a material point contact algorithm proposed by Bardenhagen is adopted between the air and concrete structures and between the concrete structures and rock and soil bodies. And after the calculation is finished, outputting the overpressure value and wavefront distribution of each air matter particle, outputting the stress value, displacement value and plastic strain value of each concrete matter particle, and outputting the stress value, displacement value and plastic strain value of each rock matter particle. And remapping the calculation result on each material point to the background grid node. And (4) obtaining a distribution cloud picture of each calculation result by adopting an interpolation algorithm on the nodes. And judging whether the time to the end point is calculated or not, if not, switching to the next time step, and if so, ending.
The subway tunnel structure part adopts an HJC concrete model, and parameters such as initial density, unconfined compressive strength, elastic volume modulus, specific heat capacity and the like of a concrete material need to be input. HJC the concrete model equation of state is shown in equations (17) - (19):
elastic phase p ═ K elastic μ (17)
Transition phase
Compaction stage
Wherein p is the concrete ball stress, K elastic Is the elastic volume modulus, mu is the elastic volume strain,
is plastic volume strain, F is compaction factor, K 1 ，K 2 ，K 3 Are all material parameters. In this example, K 1 The values are: 85GPa, K 2 The values are as follows: 171GPa, K 3 The values are as follows: 208 GPa.
The concrete structure internal reinforcing steel bars are dispersed into rod units by adopting a hybrid particle method. The rod unit nodes move together with the concrete material points. The constitutive model of the rod unit node adopts an ideal elastic-plastic model, and parameters such as shear modulus, plastic modulus and the like need to be input. The material model of the steel bar is shown as the formula (20):
in the formula, σ y To yield stress,. epsilon p In order to be equivalent to the plastic strain,
is a dimensionless equivalent plastic strain rate, A is a reference strain rate and an initial yield stress at a reference temperature, B is a material strain hardening modulus, n is a hardening parameter, C is a material strain rate strengthening parameter, m is a softening parameter of the material, and T is a softening parameter of the material * Is a dimensionless temperature.
The surrounding rock-soil body adopts a DP constitutive model, and the parameters of cohesive force, internal friction angle and the like of the rock-soil body need to be input. The model yield function is shown in equation (21):
wherein f is the yield function, I 1 Is a first constant of stress, J 2 And is a second bias stress invariant, and alpha and k are normal numbers. In this embodiment, α is 0.134, and k is 11.11 kPa.
In the state equation of explosive explosion, parameters such as internal energy per unit volume, detonation velocity, initial density, specific heat ratio and the like of the explosive need to be input. The state equation adopted by explosive explosion is shown as formula (22):
where p is the pressure of the detonation products, E is the internal energy per unit initial volume of the detonation products, V is the volume of the detonation products, A, B, R 1 、R 2 And ω is a user-defined material parameter. In this embodiment, the value of A is 371.2GPa, the value of B is 3.23GPa, and R 1 A value of 4.15, R 2 The value is 0.95 and omega is 0.30.
The air adopts a linear polynomial equation of state, and parameters such as air density, specific heat ratio, wave speed and the like need to be input. The air adopts a linear polynomial state equation as shown in the formula (23);
p＝c 0 +c 1 μ+c 2 μ 2 +c 3 μ 3 +(c 4 +c 5 μ+c 6 μ 2 )E (23)
wherein p is pressure, c 0 ～c 6 For custom material constants, μ is the air volume strain and E is the internal energy per unit volume of air. In this example, c 0 ～c 6 The values are as follows in sequence: 0,0,0,0,0.4,0.4,0.
5) And comparing the impact wave overpressure in the table 1 with personnel injury grade division standards, and drawing a personnel injury grade partition map according to an overpressure distribution cloud map.
TABLE 1
6) Determining a structural damage factor by using the equivalent plastic strain increment and the plastic volume strain increment at the current moment and the ratio of the accumulated total equivalent plastic strain and the plastic volume strain:
wherein D is a damage factor, Δ ε p And Δ μ p Respectively an equivalent plastic strain increment and a plastic volume strain increment of the current time step;
and
total equivalent plastic strain and total plastic volume strain, respectively. And then drawing a damage factor cloud picture, and drawing a structural damage grade partition picture by comparing with structural damage grade division standards in the table 2.
TABLE 2
7) And carrying out comprehensive explosion accident hazard evaluation according to the personnel injury grade partition map and the structural injury grade partition map.
8) Changing the equivalent weight of different explosives, the positions of explosion points, the structural forms and the material parameters, repeating the steps, and analyzing the change rule of the explosion accident risk in different scenes according to different simulation results.
The method overcomes the defects of the traditional qualitative evaluation based on experience, overcomes the numerical difficulty of the traditional finite element simulation method caused by grid distortion during explosion simulation, provides a set of feasible quantitative evaluation method for harmfulness, has a certain practical application value, has a positive propulsion effect on the formulation of a special emergency plan, and has a guiding significance on post-disaster emergency repair and later recovery work.
Example 7:
the main steps of this embodiment are the same as those of embodiment 1, wherein a certain subway station is selected in this embodiment, the size of the whole model is 99m × 61m × 40m, the platform structure size is 19m × 61m × 6m, and the structure thickness is 1 m. The three-dimensional model shown in figure 2 was constructed and discretized into 247599 particles with a 1m x 1m background grid placed over the entire area, with the explosive equivalent set at 5kg, at the geometric centre of the platform structure floor. After numerical calculation is carried out on the model by using a particle method, an overpressure distribution cloud chart as shown in fig. 3 is obtained, and a personnel injury grade partition chart is drawn according to the standard of classification of the impact wave overpressure on the personnel injury grade as shown in fig. 4. Then, the concrete floor damage factor distribution cloud charts shown in fig. 5 and 7 are obtained through calculation, and according to the structural damage grade division standard, the structural damage grade division charts shown in fig. 6 and 8 are drawn.
Example 8:
the embodiment discloses a method for evaluating the hazard of an explosion accident of a subway tunnel based on a generalized interpolation material point method, which comprises the following steps of:
1) and constructing an engineering physical model according to the engineering structural characteristics. The engineering physical model comprises a structural model of the subway tunnel and a geological model of surrounding rock and soil masses. Discretizing a continuum of an engineering physics model to N p Each material point is assigned a corresponding material parameter. And covering the whole calculation domain by adopting a uniform structural grid to generate a background grid.
2) And setting the initial condition, the boundary condition and the load condition of the engineering physical model, and setting the time step length of each step of calculation.
3) Setting the position of the detonation point according to the actual situation, and calculating the equivalent weight of the explosive according to the type and the volume of the explosive.
4) And solving the explosion response by using a material dot method. And (3) carrying out explicit dynamic solution on the three-dimensional models of the infrastructure structure and the surrounding rock-soil mass under the action of explosion by utilizing a generalized interpolation material particle method.
The explosion response calculation flow of a single time step is as follows: and mapping the material point information and the external force to the background grid nodes. And (4) carrying out display integration solution on the model by using a generalized interpolator particle method containing a contact algorithm. And after the calculation is finished, outputting the overpressure value and wavefront distribution of each air matter particle, outputting the stress value, displacement value and plastic strain value of each concrete matter particle, and outputting the stress value, displacement value and plastic strain value of each rock matter particle. And remapping the calculation result on each material point to the background grid node. And (4) obtaining a distribution cloud picture of each calculation result by adopting an interpolation algorithm on the nodes. And judging whether the time to the end point is calculated or not, if not, switching to the next time step, and if so, ending.
The subway tunnel structure part adopts HJC concrete model, HJC concrete model equation of state is shown in formulas (8) - (10):
elastic phase p ═ K elastic μ (8)
Transition phase
Compaction phase
Wherein p is the concrete ball stress, K elastic Is the elastic volume modulus, mu is the elastic volume strain,
is plastic volume strain, F is compaction factor, K 1 ，K 2 ，K 3 Are all material parameters. In this example, K 1 The values are as follows: 85GPa, K 2 The values are: 171GPa, K 3 The values are as follows: 208 GPa.
The concrete structure internal reinforcing steel bars are dispersed into rod units by adopting a hybrid particle method. The rod unit nodes move together with the concrete material points. The constitutive model of the rod unit node adopts an ideal elastic-plastic model. The material model of the steel bar is shown as the formula (11):
in the formula, σ y To yield stress,. epsilon p In order to be equivalent to the plastic strain,
is a dimensionless equivalent plastic strain rate, A is a reference strain rate and an initial yield stress at a reference temperature, B is a material strain hardening modulus, n is a hardening parameter, C is a material strain rate strengthening parameter, m is a softening parameter of the material, and T is a softening parameter of the material * Is a dimensionless temperature.
The surrounding rock-soil mass adopts a DP constitutive model, and the yield function of the model is shown as the formula (12):
wherein f is the yield function, I 1 Is a first constant of stress, J 2 And is a second bias stress invariant, and alpha and k are normal numbers. In this embodiment, α is 0.134, and k is 11.11 kPa.
The state equation adopted by explosive explosion is shown as formula (13):
where p is the pressure of the detonation products, E is the internal energy per unit initial volume of the detonation products, V is the volume of the detonation products, A, B, R 1 、R 2 And ω is a user-defined material parameter. In this embodiment, the value of A is 371.2GPa, the value of B is 3.23GPa, and R 1 A value of 4.15, R 2 The value is 0.95 and omega is 0.30.
Air is expressed by the equation of state of a linear polynomial as in equation (14):
p＝c 0 +c 1 μ+c 2 μ 2 +c 3 μ 3 +(c 4 +c 5 μ+c 6 μ 2 )E (14)
wherein p is pressure, c 0 ～c 6 For custom material constants, μ is the air volume strain and E is the internal energy per unit volume of air. In this example, c 0 ～c 6 The values are as follows in sequence: 0,0,0,0,0.4,0.4,0.
Utilizing a generalized interpolation material dot method to carry out explicit dynamic solution on a three-dimensional model of an infrastructure structure and surrounding rock-soil mass under the action of explosion, wherein the form function and the derivative of the form function of the generalized interpolation material dot method are shown in formulas (15) to (16):
wherein L is the length of the grid, 2L p Is the particle length, x p Are the coordinates of the particles. x is the number of I Are the coordinates of the nodes.
5) Drawing an overpressure distribution cloud chart according to the explosion response; and (5) drawing a personnel injury grade partition map according to the personnel injury grade division standard.
6) And drawing a damage factor cloud picture according to the explosion response. And drawing a structural damage grade partition diagram according to the structural damage grade division standard.
7) And carrying out comprehensive explosion accident hazard evaluation according to the personnel injury grade partition map and the structural injury grade partition map.
8) Changing the equivalent weight of different explosives, the positions of explosion points, the structural forms and the material parameters, repeating the steps, and analyzing the related steps of the change rule of the explosion accident risk in different scenes according to different simulation results.
It should be noted that the Material Point Method (MPM) as a non-grid algorithm has the advantages of no grid distortion, no convection term in the control equation, and the like. The embodiment provides an effective way for researching the harmfulness evaluation method of the subway tunnel explosion accident.
Claims (4)
1. A method for evaluating the hazard of an explosion accident of a subway tunnel based on a generalized interpolation material point method is characterized by comprising the following steps:
1) constructing an engineering physical model according to the engineering structure characteristics; the engineering physical model comprises a structural model of the subway tunnel and a geological model of surrounding rock and soil masses; discretizing a continuum of an engineering physics model to N p Each material point is endowed with corresponding material parameters; covering the whole calculation domain by adopting a uniform structural grid to generate a background grid;
2) setting initial conditions, boundary conditions and load conditions of the engineering physical model, and setting the time step length of each step of calculation;
3) setting the position of a detonation point according to actual conditions, and calculating the equivalent weight of the explosive according to the type and volume of the explosive;
4) solving explosion response by using a material dot method;
5) drawing an overpressure distribution cloud chart according to the explosion response; drawing a personnel injury grade partition map according to personnel injury grade division standards;
6) drawing a damage factor cloud picture according to the explosion response; drawing a structure damage grade partition diagram according to the structure damage grade division standard;
7) and carrying out comprehensive explosion accident hazard evaluation according to the personnel injury grade partition map and the structural injury grade partition map.
2. A method for evaluating the harmfulness of an explosion accident of a subway tunnel based on a generalized interpolation material point method according to claim 1, wherein in the step 4), an explosion response calculation process of a single time step is as follows: mapping the material point information and the external force to background grid nodes; carrying out display integral solution on the model by utilizing a generalized interpolation material dot method containing a contact algorithm; after the calculation is finished, outputting the overpressure value and wavefront distribution of each air matter particle, outputting the stress value, displacement value and plastic strain value of each concrete matter particle, and outputting the stress value, displacement value and plastic strain value of each rock matter particle; remapping the calculation results on the material points to the background grid nodes; and (4) obtaining a distribution cloud picture of each calculation result by adopting an interpolation algorithm on the nodes. And judging whether the time to the end point is calculated or not, if not, switching to the next time step, and if so, ending.
3. The method for evaluating the harmfulness of the subway tunnel explosion accident based on the generalized interpolation material point method according to claim 1 or 2, is characterized in that: in the step 4), the subway tunnel structure part adopts an HJC concrete model; dispersing the steel bars in the concrete structure into rod units by adopting a hybrid material point method; the rod unit node and the concrete material point move together; the constitutive model of the rod unit node adopts an ideal elastic-plastic model.
4. The method for evaluating the harmfulness of the subway tunnel explosion accident based on the generalized interpolation material point method according to claim 1 or 3, is characterized in that: and 7) after the step 7), changing the equivalent weight of different explosives, the positions of explosion points, the structural forms and the material parameters, repeating the steps, and analyzing the related change rules of the explosion accident risk in different scenes according to different simulation results.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210102209 | 2022-01-27 | ||
| CN2022101022093 | 2022-01-27 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114862087A true CN114862087A (en) | 2022-08-05 |
Family
ID=82627097
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210195662.3A Pending CN114862087A (en) | 2022-01-27 | 2022-03-01 | Generalized interpolation object particle method-based subway tunnel explosion accident hazard evaluation method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114862087A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114547870A (en) * | 2022-01-27 | 2022-05-27 | 重庆大学 | Tunnel damage assessment method under fire disaster-explosion based on particle method |
| CN115408907A (en) * | 2022-08-26 | 2022-11-29 | 中国地质调查局军民融合地质调查中心 | Method and system for evaluating anti-knock striking performance of earth surface |
-
2022
- 2022-03-01 CN CN202210195662.3A patent/CN114862087A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114547870A (en) * | 2022-01-27 | 2022-05-27 | 重庆大学 | Tunnel damage assessment method under fire disaster-explosion based on particle method |
| CN114547870B (en) * | 2022-01-27 | 2024-04-05 | 重庆大学 | Method for evaluating tunnel damage under fire disaster-explosion based on object particle method |
| CN115408907A (en) * | 2022-08-26 | 2022-11-29 | 中国地质调查局军民融合地质调查中心 | Method and system for evaluating anti-knock striking performance of earth surface |
| CN115408907B (en) * | 2022-08-26 | 2024-02-23 | 中国地质调查局军民融合地质调查中心 | Method and system for evaluating surface antiknock striking performance |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Abedini et al. | Comparison of ALE, LBE and pressure time history methods to evaluate extreme loading effects in RC column | |
| Yuan et al. | A study of RC bridge columns under contact explosion | |
| Sarhosis et al. | A detailed micro-modelling approach for the structural analysis of masonry assemblages | |
| Jiang et al. | Failure performance of 3DP physical twin-tunnel model and corresponding safety factor evaluation | |
| Wu et al. | Residual axial compression capacity of localized blast-damaged RC columns | |
| Fan et al. | Mechanical behavior of rock-like jointed blocks with multi-non-persistent joints under uniaxial loading: a particle mechanics approach | |
| Anil et al. | Experimental and numerical investigation of reinforced concrete beams with variable material properties under impact loading | |
| CN114862087A (en) | Generalized interpolation object particle method-based subway tunnel explosion accident hazard evaluation method | |
| Adhikary et al. | Dynamic behavior of reinforced concrete beams under varying rates of concentrated loading | |
| Jiang et al. | Simulation of cracking near a large underground cavern in a discontinuous rock mass using the expanded distinct element method | |
| Amnieh et al. | Dynamic analysis of non-homogeneous concrete blocks mixed by SiO2 nanoparticles subjected to blast load experimentally and theoretically | |
| Jin et al. | Numerical study on the impact performances of reinforced concrete beams: A mesoscopic simulation method | |
| Xu et al. | Four-point combined DE/FE algorithm for brittle fracture analysis of laminated glass | |
| Castedo et al. | Numerical study and experimental tests on full-scale RC slabs under close-in explosions | |
| Min et al. | Influence of cracks at the invert on the mechanical behavior of the tunnel structures | |
| Lu et al. | Large-scale test as the basis of investigating the fire-resistance of underground RC substructures | |
| Abdel-Motaal et al. | Mutual seismic interaction between tunnels and the surrounding granular soil | |
| CN101603285A (en) | A kind of runway arresting system and block the Forecasting Methodology of performance | |
| Ma et al. | Research on propagation laws of explosion shock wave inside metro station | |
| Li et al. | A numerical study of the overall stability of flexible giant crane booms | |
| Anil et al. | Experimental and numerical study of rc columns under lateral low-velocity impact load | |
| CN114547870B (en) | Method for evaluating tunnel damage under fire disaster-explosion based on object particle method | |
| Chee et al. | Shallow buried RC structures behavior under airblast in the time and PI domains | |
| Draganić et al. | Numerical simulation of effect of explosive action on overpasses | |
| Liao et al. | Experimental study on consistency of the impact performance between composite beams and reinforced concrete beams |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |