CN116975969A

CN116975969A - Method and system for real-time positioning and damage quantification of concrete dam crack expansion under explosive load

Info

Publication number: CN116975969A
Application number: CN202310887312.8A
Authority: CN
Inventors: 李典庆; 苏正洋; 王顺; 许宵; 王睿珺
Original assignee: Wuhan University WHU
Current assignee: Wuhan University WHU
Priority date: 2023-07-19
Filing date: 2023-07-19
Publication date: 2023-10-31
Anticipated expiration: 2043-07-19
Also published as: CN116975969B

Abstract

The invention provides a method and a system for real-time positioning and damage quantification of concrete dam crack extension under explosive load, which can objectively, efficiently and accurately perform real-time crack identification, positioning and damage quantification. The method comprises the following steps: step 1, pretreatment; step 2, constructing a numerical simulation frame under the action of explosion load; step 2-1, setting a dam particle constitutive model and a breaking criterion of the dam particles; step 2-2, converting the contact force of the interaction of the particles of different materials into stress; taking the water pressure and the lifting pressure as a layer of mechanical boundary containing pressure information; step 2-3, carrying out fracture damage judgment and characteristic information solving on the dam particles; step 2-4, simulating concrete fracture expansion; and step 3, obtaining damage types of damage particles and the number of the damage particles corresponding to each damage type through a numerical simulation framework, thereby determining the damage types in real time, and classifying, quantifying and evaluating the damage evolution process of the concrete dam under the action of explosion load in real time respectively or totally.

Description

Method and system for real-time positioning and damage quantification of concrete dam crack expansion under explosive load

Technical Field

The invention belongs to the technical field of concrete dam antiknock, and particularly relates to a method and a system for real-time positioning and damage quantification of crack expansion of a concrete dam under explosive load.

Background

At present, the demands of high-efficiency water resource utilization, hydropower energy development and the like are higher and higher, and a series of 100-300 m-level high dams are built, are currently or are about to be built. The dam (most of concrete dams) has serious loss of results, and the dam antiknock safety evaluation and protection problems under the action of sudden explosion impact load are worth focusing on. The nonlinear dynamic response behavior and damage mechanism of the concrete dam under the action of explosion load are researched, the crack propagation path of the dam is accurately identified, the crack evolution process of the dam after the dam is subjected to explosion attack is evaluated, and the method is very important for improving the antiknock safety of hydraulic and hydroelectric engineering.

At present, the concrete dam antiknock research is concentrated on the aspects of tests and numerical simulation. In the aspect of the test, due to the limitations of test conditions and expenses and the defects that the similarity of a scaling model is difficult to meet at the same time, the data of an explosion near field region is difficult to collect accurately, adverse effects on the surrounding environment are easy to cause and the like, the research results of the dam explosion test are relatively few, which are reported in public at home and abroad. Although the centrifuge test has certain advantages in the aspect of developing the structural underwater explosion antiknock performance evaluation, certain technical problems still exist in simulating the dam explosion damage effect, and the technical problems mainly comprise: the model size of the centrifuge test is often smaller, factors such as dam key holes, construction joints, foundation surfaces and the like are difficult to consider, the small-dose explosion test in the centrifuge is difficult to reproduce the equivalent near-field explosion damage characteristics, complex shock wave reflection can be generated in the centrifuge after the explosion of the explosive, the dynamic response of the structure is influenced and the like.

In the aspect of numerical simulation, aiming at crack expansion, students calculate crack expansion and damage conditions of a dam by adopting an expansion finite element method, but the method is that the positions and the expansion directions of the cracks are preset, the positions and the expansion directions are possibly inconsistent with the actual expansion process, the grid is required to be reconstructed in the calculation process, the calculation amount is very large, and the problem of error accumulation exists. Some students use a combination of Finite Element (FEM) and smooth particle fluid dynamics (SPH) methods to calculate crack propagation of a concrete dam under explosive load, such methods generally set a region in advance as a potential SPH particle region, the model is initially composed of grids, stress or strain is generally used as a discrimination condition, when the stress or strain value of a certain region reaches a preset value, the crack is considered to be generated at this time, and the grids of the part in the model are converted into SPH particles. This approach also suffers from drawbacks such as the inability to calculate if the actual fracture propagates beyond the model area preset as SPH particles. In addition, the method has to be improved in terms of crack initiation criteria, crack propagation directions, damage quantification and the like, and currently lacks a unified computing framework and algorithm in terms of concrete dam antiknock computation. In addition, the current calculation is mainly focused on two-dimensional calculation due to the limitation of calculation efficiency, the defects still exist in the process of representing the three-dimensional structure of the concrete dam, one grid reaches two meters in the existing grid-based method, and the material nonuniformity is rough in representation in the process of calculating crack extension. In recent years, simulation of crack propagation by a grid-free method such as a smooth particle fluid dynamic method has been a trend, but the particle-based method has disadvantages such as difficulty in load boundary application and large calculation amount of contact judgment.

Aiming at dam damage quantification and evaluation, the existing damage evaluation method is mainly aimed at damage characteristics and damage areas of dam damage areas, strength or stability characteristics and the like of the dam damage areas are analyzed through static calculation, and calculation has more assumptions and limitations. If in the aspect of actual engineering calculation, the concrete dam explosion damage is initially evaluated, the damage effect of explosion load on materials cannot be quantified by the traditional material mechanics method, the strength and stability of the dam are calculated, the strength parameters are often reduced, and the parameter selection has a certain subjectivity. Therefore, the current mainstream method is to quantify the damage degree of the concrete dam by adopting damage factors, but the grid-based method can only give damage distribution cloud images, and the method for quantifying the area or the volume of a damaged area of the dam is still lacking.

Disclosure of Invention

The invention aims to solve the problems, and aims to provide the real-time positioning and damage quantification method and system for the crack expansion of the concrete dam under the explosive load, which can objectively, efficiently and accurately identify, position and quantify the crack of the dam in real time.

In order to achieve the above object, the present invention adopts the following scheme:

< method >

The invention provides a method for real-time positioning and damage quantification of crack propagation of a concrete dam under an explosive load, which is characterized by comprising the following steps:

Step 1, a three-dimensional solid model of a concrete dam is established through modeling software, and then the concrete dam is discretized into equidistant particle models;

step 2, constructing a numerical simulation frame under the action of explosion load on the basis of the step 1;

step 2-1, selecting a linear elastic solid constitutive equation as a dam particle constitutive model, and setting a breaking damage criterion of the dam particles;

step 2-2, converting the contact force of the interaction of the particles of different materials into stress;

the water pressure and the lifting pressure are used as a layer of mechanical boundary n containing pressure information _x,i Treating, characterizing its properties by a layer of particles, and setting the upstream water level difference as H _w The water pressure distributed along the upstream dam face of the concrete dam is P _w The elevating force distributed along the bedrock surface is U _w The explosion pressure is P _E The method comprises the steps of carrying out a first treatment on the surface of the The dam particles, the reservoir water particles, the explosive particles and the elevating force particles are endowed with different particle type values for distinguishing; the reservoir water particles and the lifting pressure particles are all single layers;

1) The contact force between the dam particles i and the reservoir water particles caused by the water pressure is converted into stress to which the dam particles i are subjected:

in the method, in the process of the invention,represents the pressure of water from dam particles i as P _w Stress components caused by single-layer water particles in the directions of stress xx, yy and xy respectively; and n _y,i Direction vectors along the x and y directions, respectively; ρ is density, g is gravitational acceleration;

2) The contact force between the dam particles i and the pumping force particles caused by pumping force is converted into stress to which the dam particles i are subjected:

in the method, in the process of the invention,indicating that the dam particles i are subjected to a lifting force U _w Stress components caused by pressure components of single-layer lifting pressure particles in the directions of stress xx, yy and xy respectively;

3) The contact force between the dam particles i and the explosive particles caused by the explosion pressure is converted into stress to which the dam particles i are subjected:

in the method, in the process of the invention,representing the pressure of explosion P experienced by the dam particles i _E Stress components caused by pressure components of explosive particles in the directions of stress xx, yy and xy respectively;

wherein, the step 2-1 and the step 2-2 have no sequence;

step 2-3, carrying out fracture damage judgment and characteristic information solving on the dam particles based on the steps 2-1 to 2-2;

firstly, carrying out contact judgment on the current dam particle i and all other N particles in the influence domain of the dam particle i, calculating stress among corresponding material particles according to the step 2-2 after judging that the current dam particle i is in contact, otherwise, carrying out traversal to obtain stress caused by other N particles received by the dam particle i, accumulating the stress to obtain stress state information of the dam particle i, determining whether the dam particle i is broken and damaged according to the stress state information by a breaking and damage criterion, changing the value of a breaking shielding mark xi to be xi=0 when the particle is broken and damaged, marking the dam particle as damaged particle, otherwise, xi=1, and finally solving characteristic information of the dam particle i according to the breaking shielding mark xi and the stress received by the dam particle i; repeating the process for each dam particle to be simulated until all the dam particles to be simulated are traversed; the characteristic information at least comprises stress, strain, acceleration, speed and density information;

Step 2-4, simulating concrete fracture expansion;

taking the characteristic information and the xi value obtained by calculating the current time step as initial values for calculating the next time step; repeating the above process until reaching the preset time step number; simulating crack propagation conditions of the concrete dam through characteristic information of each dam particle in different time steps;

and step 3, obtaining the damage types of the damage particles and the number of the damage particles corresponding to each damage type through the numerical simulation framework in the step 2, thereby determining the damage types in real time, and classifying, respectively or totally quantifying and evaluating the damage evolution process of the concrete dam under the action of explosion load in real time.

In the process, the crack propagation direction of the concrete dam is judged based on the fracture criteria, and the reservoir water boundary, the pumping force boundary, the explosive region and the dam material are characterized by adopting particles.

Preferably, in the method for real-time positioning and damage quantification of concrete dam crack extension under explosive load, in the step 2-3, the actions of water pressure, lifting force and explosive load are considered, meanwhile, fracture shielding marks xi are introduced to represent the particle state, and the stress calculated in the step 2-2 is brought into the following formula to solve the characteristic information of dam particles i:

Wherein: t is the calculation time; m is mass; v is the velocity of the dam particles; x is the position coordinates of the particle; t is an artificial sticky term; w is a smooth kernel function; delta and beta refer to vector directions of stress, the stress is a third-order tensor, and delta and beta can respectively take three directions of 1,2 and 3; taking dam i particles as the center, surrounding N particles, and marking j as dam particles, explosive particles, reservoir water particles or elevating pressure particles;stress of j particles to i particles, +.>The stress of the i particles to the j particles is that the j particles and the i particles are dam particles; />In the case of the existence of water particles in the influence domain, the water pressure P generated by the water particles _W Stress on the j particles; />In the case of the existence of the winnowing pressure particles in the influence domain, the winnowing pressure U generated by the winnowing pressure particles _W Stress on the j particles; />In order to influence the explosive pressure P generated by the explosive particles in the presence of the explosive particles in the domain _E Stress on the j particles.

Preferably, in the method for real-time positioning and damage quantification of crack propagation of a concrete dam under explosive load provided by the invention, in the step 2-3, contact judgment between a dam particle i and other particles is specifically as follows: taking the current dam particle i as a center, setting the particle radius as r, wherein the influence area of the dam particle i is f times the radius range of the surrounding area, f is more than or equal to 2, and if particles exist in the influence area, the contact action with the dam particle i is divided into four types, namely the contact with the same type of dam particles, the contact with reservoir water particles, the contact with the elevating pressure particles and the contact with explosive particles, and judging the contact type through a particle type value; if the dam particles are judged to be in contact with the reservoir water particles, calculating stress by adopting a formula 2-2-1; if the dam particles are judged to be in contact with the lifting pressure particles, calculating stress by adopting a formula 2-2-2; if the dam particles are judged to be in contact with the explosive particles, calculating stress by adopting the formula 2-2-3; if the dam particles are judged to be in contact with the dam particles, the stress is calculated by the constitutive equation.

In the method for real-time positioning and damage quantification of concrete dam crack extension under explosive load, in the step 2-3, if the current dam particle i is judged to be broken and destroyed, and xi=0, the channel of information communication between the dam particle i and surrounding particles is shielded, the contact force between the dam particle i and other particles in an influence domain is not calculated any more, and the judgment of the dam particle i is ended; and then carrying out fracture damage judgment on the next dam particles. Preferably, in the method for real-time positioning and damage quantification of concrete dam crack extension under explosive load provided by the invention, in step 2-1, the fracture criteria are as follows:

σ _f ＝σ _t (2-1-1)

In sigma _f And τ _f The maximum tensile stress and the shear stress of the imaginary fracture surface; sigma (sigma) _t Is the tensile strength of the particle; c is the cohesion of the particles;is the internal friction angle of the dam material; sigma (sigma) _t 、c、σ _f All are obtained according to the stress state of the dam particles i; when the dam particles i satisfy the tensile failure condition of the formula 2-1-1, judging that the particles are tensile-broken; when the formula 2-1-1 is not satisfied, the shear failure is judged by the formula 2-1-2, and if the dam particle i satisfies the formula 2-1-2, the shear failure is judged to occur in the particle.

Preferably, in the method for positioning and quantifying concrete dam crack propagation in real time under explosive load, in step 3, the number of damaged particles under each damage type is counted in each time step to obtain the change condition of the total number of the damaged particles under each damage type along with time, so that the concrete dam damage evolution process under the action of explosive load is quantified and evaluated respectively in a classified manner; and summing the numbers of the damaged particles under all the damage types in each time step to obtain the time-dependent change condition of the total number of the damaged particles of the concrete dam, thereby comprehensively quantifying and evaluating the damage evolution process of the concrete dam under the action of explosion load.

Preferably, the method for real-time positioning and damage quantification of concrete dam crack extension under explosive load provided by the invention further comprises the following steps: and 4, according to the damage degree of the concrete dam positioned and quantified in the step 3 under different damage types, selecting a proper material according to the corresponding damage type and the damage degree to perform reinforcement simulation on the corresponding crack area of the concrete dam so as to obtain the optimal reinforcement effect.

Preferably, the method for real-time positioning and damage quantification of concrete dam crack propagation under explosion load provided by the invention comprises the following steps of 2-2, wherein the pressure P generated by explosion of explosive materials _E The following formula is adopted for calculation:

where V is the relative volume and E is the initial internal energy per unit volume of explosive, a=3.712×10 ¹¹ Pa，B＝3.231×10 ⁹ Pa，R ₁ ＝4.15，R ₂ ＝0.95，ω＝0.3。

Preferably, in the method for real-time positioning and damage quantification of concrete dam crack propagation under explosive load provided by the invention, in step 1, a sampling algorithm is used for dispersing a solid model into an equidistant particle model; and the shear strength parameters of the dam are subjected to Weber distribution treatment by considering the spatial variation characteristics of the strength parameters of the dam.

< System >

Furthermore, the invention also provides a real-time positioning and damage quantifying system capable of automatically realizing the crack expansion of the concrete dam under the explosive load of the method, which is characterized by comprising the following steps:

The pretreatment part establishes a concrete dam three-dimensional solid model through modeling software, and then discretizes the concrete dam three-dimensional solid model into equidistant particle models;

a numerical simulation frame construction part for constructing a numerical simulation frame under the action of explosion load based on the equidistant particle model; comprising the following steps: the device comprises a setting unit, a contact force conversion unit, a judgment solving unit and a fracture expansion simulation unit;

the setting unit is used for selecting a linear elastic solid constitutive equation as a dam particle constitutive model and setting a breaking and breaking criterion of the dam particles;

a contact force conversion unit for converting the contact force of the interaction of the particles of different materials into stress; the water pressure and the lifting pressure are treated as a layer of mechanical boundary containing pressure information, a layer of particles is adopted to characterize the property of the pressure information, and the upstream water level difference is set as H _w The water pressure distributed along the upstream dam face of the concrete dam is P _w The elevating force distributed along the bedrock surface is U _w The explosion pressure is P _E The method comprises the steps of carrying out a first treatment on the surface of the The dam particles, the reservoir water particles, the explosive particles and the elevating force particles are endowed with different particle type values for distinguishing; the reservoir water particles and the lifting pressure particles are all single layers;

In the method, in the process of the invention,represents the pressure of water from dam particles i as P _w Stress components caused by single-layer water particles in the directions of stress xx, yy and xy respectively; n is n _x,i And n _y,i Direction vectors along the x and y directions, respectively; ρ is density, g is gravitational acceleration;

the judging and solving unit is used for judging the fracture and damage of the dam particles and solving the characteristic information; firstly, judging that the current dam particle i contacts with all other N particles in the influence domain, calculating stress among corresponding material particles according to the step 2-2 after judging that the current dam particle i contacts, otherwise, traversing to obtain stress caused by other N particles received by the dam particle i, accumulating the stress to obtain stress state information of the dam particle i, determining whether the dam particle i is broken and damaged according to the stress state information through a breaking damage criterion, changing the value of a breaking shielding mark zeta to be zeta=0 (adopting the contact force effect between broken particles shielded by a breaking shielding mark coefficient zeta and intact particles, marking the broken particles as damaged particles at the moment), marking the dam particle as damaged particles, otherwise, zeta=1, and finally solving the characteristic information of the dam particle i according to the broken shielding mark zeta and the stress received by the dam particle i; repeating the process for each dam particle to be simulated until all the dam particles to be simulated are traversed;

The fracture expansion simulation unit is used for performing concrete fracture expansion simulation; taking the characteristic information and the xi value obtained by calculating the current time step as initial values for calculating the next time step; repeating the above process until reaching the preset time step number; simulating crack propagation conditions of the concrete dam through characteristic information of each dam particle in different time steps;

the quantitative evaluation part is used for obtaining the damage types of the damage particles and the number of the damage particles corresponding to each damage type based on the numerical simulation framework, so as to determine the damage types in real time, and classifying, respectively or totally quantifying and evaluating the damage evolution process of the concrete dam under the action of explosion load in real time;

and the control part is in communication connection with the preprocessing part, the numerical simulation framework construction part and the quantitative evaluation part and controls the operation of the preprocessing part, the numerical simulation framework construction part and the quantitative evaluation part.

Preferably, the system for real-time positioning and damage quantification of concrete dam crack extension under explosive load provided by the invention further comprises: and the input display part is communicated with the control part, and allows an operator to input an operation instruction and display the operation instruction correspondingly.

Preferably, the system for real-time positioning and damage quantification of concrete dam crack extension under explosive load provided by the invention further comprises: and the early warning part is in communication connection with the control part and carries out real-time early warning on dam damage according to the safety threshold and the real-time quantized and estimated concrete dam damage evolution process under the action of the explosion load of the quantized and estimated part.

Preferably, in the real-time positioning and damage quantifying system for concrete dam crack extension under explosive load provided by the invention, in the judging and solving unit, the action of water pressure, lifting force and explosive load is considered, meanwhile, a fracture shielding mark xi is introduced to represent the particle state, and the stress calculated by the contact force converting unit is brought into the following formula to solve the characteristic information of dam particles i:

wherein: t is the calculation time; m is mass; v is the velocity of the dam particles; x is the position coordinates of the particle; t is an artificial sticky term; w is a smooth kernel function; delta and beta refer to vector directions of stress, the stress is a third-order tensor, and delta and beta can respectively take three directions of 1,2 and 3; taking dam i particles as the center, surrounding N particles, and marking j as dam particles, explosive particles, reservoir water particles or elevating pressure particles;stress of j particles to i particles, +.>The stress of the i particles to the j particles is that the j particles and the i particles are dam particles; />In the case of the existence of water particles in the influence domain, the water pressure P generated by the water particles _W Stress on the j particles; />To influence the existence of a domainIn the case of the pumping force particles, pumping force U generated by the pumping force particles _W Stress on the j particles; / >In order to influence the explosive pressure P generated by the explosive particles in the presence of the explosive particles in the domain _E Stress on the j particles.

Preferably, in the real-time positioning and damage quantifying system for concrete dam crack propagation under explosive load provided by the invention, in the judging and solving unit, the contact judgment between the dam particles i and other particles is specifically as follows: taking the current dam particle i as a center, setting the particle radius as r, wherein the influence area of the dam particle i is f times the radius range of the surrounding area, f is more than or equal to 2, and if particles exist in the influence area, the contact action with the dam particle i is divided into four types, namely the contact with the same type of dam particles, the contact with reservoir water particles, the contact with the elevating pressure particles and the contact with explosive particles, and judging the contact type through a particle type value; if the dam particles are judged to be in contact with the reservoir water particles, calculating stress by adopting a formula 2-2-1; if the dam particles are judged to be in contact with the lifting pressure particles, calculating stress by adopting a formula 2-2-2; if the dam particles are judged to be in contact with the explosive particles, calculating stress by adopting the formula 2-2-3; if the dam particles are judged to be in contact with the dam particles, the stress is calculated by the constitutive equation.

Preferably, in the real-time positioning and damage quantifying system for concrete dam crack propagation under explosive load provided by the invention, if the current dam particle i is judged to be broken and destroyed, and ζ=0, shielding the channel of the information communicated between the dam particle i and surrounding particles, and not calculating the contact force between the dam particle i and other particles in the influence domain, wherein the judgment of the dam particle i is finished; and then carrying out fracture damage judgment on the next dam particles. Preferably, the method for real-time positioning and damage quantification of concrete dam crack extension under explosion load provided by the invention has the following breaking criteria in the setting unit:

σ _f ＝σ _t (2-1-1)

Preferably, the real-time positioning and damage quantification system for concrete dam crack propagation under explosive load provided by the invention is characterized in that in the quantification evaluation part, the quantity of damage particles under each damage type is counted in each time step, so that the change condition of the total quantity of the damage particles under each damage type along with time is obtained, and the concrete dam damage evolution process under the action of explosive load is respectively quantified and evaluated in a classified manner; and summing the numbers of the damaged particles under all the damage types in each time step to obtain the time-dependent change condition of the total number of the damaged particles of the concrete dam, thereby comprehensively quantifying and evaluating the damage evolution process of the concrete dam under the action of explosion load.

Preferably, the method for real-time positioning and damage quantification of concrete dam crack extension under explosive load provided by the invention further comprises the following steps: and the reinforcement simulation part is used for performing reinforcement simulation on corresponding crack areas of the concrete dam by selecting proper materials according to the corresponding damage types and the damage degrees according to the damage degrees of the concrete dam positioned and quantized in the quantization evaluation part under different damage types.

Preferably, the system for real-time positioning and damage quantification of concrete dam crack extension under explosion load provided by the invention has the advantages that in the contact force conversion unit, the pressure P generated by explosion of explosive materials is generated _E The following formula is adopted for calculation:

Preferably, in the real-time positioning and damage quantifying system for concrete dam crack propagation under explosive load provided by the invention, a sampling algorithm is used for dispersing a solid model into an equidistant particle model in a pretreatment part; and the shear strength parameters of the dam are subjected to Weber distribution treatment by considering the spatial variation characteristics of the strength parameters of the dam.

Preferably, in the concrete dam crack expansion real-time positioning and damage quantifying system under the explosion load, the input display part can convert digital text information obtained by each part into binary VTK file to realize visualization; and controlling particle output of different partitions through particle types to realize material output classification, and respectively outputting and displaying binary files containing dams, explosives and boundary particles.

Effects and effects of the invention

(1) The invention breaks through the limitation that the traditional grid method needs to reconstruct grids and preset crack propagation paths, builds a numerical simulation frame under the action of explosion load for the first time, does not need grids, and realizes the high-efficiency, accurate and real-time quantitative evaluation of the large deformation, crack propagation simulation and damage of the concrete dam under the action of explosion load under the frame, and the calculated amount is less.

(2) According to the concrete dam concrete expansion method, concrete dam centimeter-level fine modeling and high-fidelity modeling can be realized, the spatial variation characteristic of concrete strength parameters is considered, cracks and expansion paths thereof can be positioned and calculated more accurately, and technical support is provided for targeted risk removal reinforcement of the concrete dam after being attacked by explosion load.

(3) The method solves the problems of difficult identification, difficult quantification and difficult prediction of the internal damage of the traditional concrete dam, realizes the real-time accurate identification, positioning and quantification of the internal damage of the concrete dam under the action of the explosion load, considers the time effect, can evaluate the damage condition of the dam caused by crack expansion in real time, can carry out strength check on the dam according to the stress field, and truly reconstructs the internal damage evolution process of the dam under the action of the explosion load.

(4) The method can be applied to the field of concrete dam explosion prevention, and comprises pre-explosion dam protection measure selection, post-explosion dam danger removal reinforcement measure selection and crack-containing dam further damage evolution analysis and evaluation.

Drawings

FIG. 1 is a schematic diagram of an algorithm for converting a solid model into a particle model according to an embodiment of the present invention;

FIG. 2 is a modeling diagram of the heterogeneous distribution of the elastic modulus of a concrete dam according to an embodiment of the present invention;

FIG. 3 is a concrete solid fracture constitutive model according to an embodiment of the invention;

FIG. 4 is a schematic diagram of different types of particle distributions in accordance with an embodiment of the present invention;

FIG. 5 is a schematic diagram of interaction of reservoir particles and dam particles and coordinate system conversion according to an embodiment of the present invention;

FIG. 6 is a schematic partial diagram of a prior art particle method according to an embodiment of the present invention;

FIG. 7 is a graph (customizable) of the blast load time profile according to an embodiment of the present invention;

FIG. 8 is a schematic diagram of the influence domain range of a dam particle i;

FIG. 9 is a graph showing comparison of crack growth morphology of a concrete sample under uniaxial compression according to an embodiment of the present invention, wherein (a) to (c) are the crack growth morphology change processes calculated by the method of the present invention, and (d) is the actual measurement result;

FIG. 10 is a simulated graph of a crack propagation process under an explosive load test according to an embodiment of the present invention, where (a) is the crack propagation process and the damaged area distribution of a sample under an explosive load test, and (b) is the maximum principal stress distribution diagram of the sample under an explosive load test;

FIG. 11 is a schematic diagram of a concrete dam high-fidelity model (in cm scale) according to an embodiment of the present invention, wherein (a) is a dam model considering parameter randomness, (b) is a front view of the concrete dam high-fidelity model, and (c) is a three-dimensional high-fidelity model perspective view of the concrete dam;

FIG. 12 shows the crack propagation process of a concrete dam under the combined action of water pressure (reservoir Shui Hezai), lifting pressure and explosive load according to the embodiment of the invention;

fig. 13 is a graph showing real-time statistical results of concrete dam damage under the combined action of water pressure, lifting force and explosion load according to an embodiment of the present invention.

Detailed Description

The concrete dam crack expansion real-time positioning and damage quantifying method and the concrete dam crack expansion real-time positioning and damage quantifying system are described in detail below with reference to the accompanying drawings.

Example 1

The method for real-time positioning and damage quantification of concrete dam crack extension under explosion load provided by the embodiment comprises the following steps:

Step 1, a three-dimensional solid model of a concrete dam is established through modeling software, and then the concrete dam is discretized into equidistant particle models; inputting a dam model, a lifting pressure particle, an explosive particle, a reservoir water particle area model, dispersing into particles, and acquiring initial particle coordinate information by taking the particles as an input model.

And building a concrete dam three-dimensional solid model in basic modeling software such as CAD or rhinoceros, and then dispersing the solid model into equidistant particle models by using a sampling algorithm. As shown in fig. 1, the sampling algorithm thinking is: setting a point inside the solid model as a seed generation point, and setting a computing domain B with a range including the solid model ₂ Particles are generated in this calculation domain, and the particle generation usage judgment criteria are as follows: when the particle is at the internal boundary B of the solid model ₁ Generating the particle when the particle is not at the internal boundary B of the solid model ₁ Discarding the particle when the particle is present, wherein B ₂ The region contains B ₁ An area.

The accuracy of dam modeling can reach centimeter level, in addition, the spatial variation characteristic of dam strength parameters is considered, weber distribution processing is carried out on the dam shear strength parameters, and the formula is as follows:

wherein x is the fundamental mechanical parameter (elastic modulus, compressive strength, cohesive force, etc.) of the particle, x ₀ Is the average value of the parameter, and m is the degree of non-uniformity of the particles. Fig. 2 shows a concrete dam model taking into account the spatial variation characteristics of the elastic modulus parameters.

inputting parameter values into each region in the model, including: velocity initialization is initially 0, density, single particle volume, elastic modulus, poisson's ratio, cohesion, internal friction angle, shear strength, particle type (four), fracture shielding mark (initially 1).

as shown in FIG. 3, a linear elastic solid constitutive model is selected, and the total stress tensor sigma is adopted ^αβ From hydrostatic pressure p and viscous shear force τ ^αβ ，σ ^αβ The expression is:

σ ^αβ ＝-pδ ^αβ +τ ^αβ (2)

the failure of the particles follows the modified maximum tensile stress criterion as follows:

σ _f ＝σ _t (3)

in sigma _f And τ _f The maximum tensile stress and the shear stress of the imaginary fracture surface; sigma (sigma) _t Is the tensile strength of the dam particles; c is the cohesion of the dam particles;is the internal friction angle of the dam material; when the particles meet the tensile failure condition of formula 3, preferentially judging the tensile failure; when equation 3 is not satisfied, the shear failure is determined by equation 4. And judging the type of the internal damage mode of the dam under the action of the explosion load according to the rule.

as shown in fig. 5, four materials, namely dam material type (i) =3, single layer reservoir water particle type (i) =4, explosive material type (i) =5, single layer elevating pressure particle type (i) =6, are considered in total in this embodiment.

The equivalent of reservoir water and lifting force is that a distributed load is applied to SPH particles, and concentrated force or distributed force cannot be directly applied to SPH in a traditional model; first, contact judgment is performed, when the reservoir particles and the dam particles are in contact, the interaction force (contact force) is calculated, otherwise, no force is generated, and the calculation of the interaction force is shown in fig. 5.

In the conventional smooth particle fluid dynamic method, only acceleration mode is adopted to apply field force such as gravity, so that distributed load such as water load and lifting force is difficult to apply, and as shown in fig. 6, in the prior art, water load is applied by arranging water particles in a region in front of a dam in the particle method, at the moment, the quantity of water particles in a reservoir is greatly increased, more contact force needs to be calculated, and the calculation cost is greatly increased; the invention breaks through the limitation of the traditional smooth particle fluid dynamic method to apply boundary conditions, treats the water pressure and the lifting force as a layer of mechanical boundary containing pressure information, and adopts a layer of particles to characterize the properties.

(1) Let the upstream water level difference be H _w Water pressure P _w The distribution along the upstream dam face of the concrete dam is as follows:

P _w ＝ρgH _w (5)

water pressure P _w Conversion to stress to which particle i is subjected:

for the dam particles i, stress components caused by water pressure in each direction are calculated as interaction forces:

in the method, in the process of the invention,representing stress components caused by pressure components in the directions of stress xx, yy and xy respectively generated by the reservoir pressure p; n is n _x,i And n _y,i The direction vectors in the x and y directions, respectively.

(2) Lifting force U _w The distribution along the bedrock face is:

in the method, in the process of the invention, _L x (i) is the abscissa of the ith particle, alpha is the lifting force reduction coefficient, rho is water density, and g is gravity acceleration.

Will raise the pressure U _w Conversion to stress to which particle i is subjected:

/>

in the method, in the process of the invention,indicating the elevating force U _w The stress components caused by the pressure components in the directions of the stress xx, yy and xy respectively; n is n _x,i And n _y,i The direction vectors in the x and y directions, respectively.

(3) Explosion pressure P _E Pressure P generated by explosion of explosive material _E The following formula is adopted for calculation:

Will explode pressure P _E Conversion to stress to which particle i is subjected:

in the method, in the process of the invention,representing the explosion pressure P _E The stress components caused by the pressure components in the directions of the stress xx, yy and xy respectively; n is n _x,i And n _y,i The direction vectors in the x and y directions, respectively.

Fig. 7 shows the explosive load change condition set in the present embodiment.

In addition, the steps 2-1 and 2-2 are in parallel relationship without sequence.

as shown in fig. 8, in this embodiment, when the dam particle i is taken as the center and the particle radius is set to r, the influence area of the dam particle i is 4 times the radius area around, and if particles exist in the influence area, the contact action with the dam particle is performed, and the contact action types are mainly divided into four types, namely, contact with the same type of dam particle, contact with the reservoir water particle, contact with the booster particle, and contact with the explosive particle.

Specifically, firstly, the current dam particle i is contacted with all other N particles in the influence domain of the current dam particle i, after the contact is judged, the stress among the corresponding material particles is calculated according to the step 2-2, otherwise, the stress is 0, the stress caused by the other N particles and received by the dam particle i is obtained through traversing, and then the stress is accumulated (in each direction Vector summation) to obtain stress state information of the dam particles i, and then obtaining sigma of the particles according to the stress state information (the stress state information can be used for obtaining sigma of the particles _t 、c、σ _f ) Determining whether the dam particles i are broken and damaged or not and the type of the broken and damaged by a breaking and damage criterion (whether 3 and 4 are met or not) and changing the value of a broken shielding mark xi to be xi=0 when the particles are broken and damaged, marking the dam particles as damaged particles, otherwise, xi=1, and finally solving the characteristic information of the dam particles i according to the broken shielding mark xi and the stress suffered by the dam particles i; repeating the process for each dam particle to be simulated until all the dam particles to be simulated are traversed; the characteristic information includes information such as stress, strain, acceleration, speed, density, and the like.

Taking the effects of water pressure, lifting force and explosion load into consideration, introducing a fracture shielding mark xi to represent the state of particles, and bringing the stress calculated in the step 2-2 into the following formula to solve the characteristic information of the dam particles i:

wherein: t is the calculation time; m is mass; v is the velocity of the dam particles; x is the position coordinates of the particle; t is an artificial sticky term; w is a smooth kernel function; alpha and beta refer to the vector direction of stress, the stress is a third-order tensor, and delta and beta can respectively take three directions of 1,2 and 3; taking dam i particles as the center, surrounding N particles, and marking j as dam particles, explosive particles, reservoir water particles or elevating pressure particles; Stress of j particles to i particles, +.>Is the stress of the i particles to the j particles, and the j particles and the i particles at the momentThe sub-components are dam particles (stress values calculated by adopting constitutive equation); />In the case of the existence of water particles in the influence domain, the water pressure P generated by the water particles _W Stress on the j particles (using the calculation result of formula 6); />In the case of the existence of the winnowing pressure particles in the influence domain, the winnowing pressure U generated by the winnowing pressure particles _W Stress on the j particles (using the calculation result of formula 8);in order to influence the explosive pressure P generated by the explosive particles in the presence of the explosive particles in the domain _E Stress on the j particles (calculation result using equation 10).

It should be noted that if the dam particle i meets the fracture criterion, i.e., the particle is damaged, the fracture shielding flag value is 0, i.e., the channel where the dam particle i communicates information with surrounding particles is shielded, and then the contact effect of this dam particle i is not calculated (including calculation centered on the dam particle i and the case where the dam particle i exists in the influence domain when calculation centered on other dam particles). The recalculation requires contact calculation centered on otherwise intact dam particles, cycling the process. If there are no pool water particles in the influence region of the current dam particle i, then in equation 12 The term is 0; if no pressure-raising particles are present, +.in formula 12>The term is 0; if no explosive particles are present, +.in formula 12>In the itemIs 0.

The fracture contact judging method comprises the following steps: the contact judgment is performed by adopting the particle type, taking the contact judgment and calculation of the explosive particles and the dam particles as an example, wherein the bidirectional contact judgment and calculation of the dam and the explosive are as follows (here, it is assumed that the two particles i and j are not determined which is the dam particle):

for j particles, when the absolute value of the itape (i) -3 is less than 0.00001 (i.e., itape (i) =3) and itape (j) =5 (also judged according to absolute value and error), the stress component caused by explosion pressure in different directions is calculated using the above formula 10; here, the calculation is performed for the case where i is a dam particle and j is an explosive particle. For the i particles, when the absolute value of the itape (i) -5 is less than 0.00001 (i.e., itape (i) =5) and itape (j) =3 (also judged according to absolute value and error), the stress component caused by the explosion pressure in different directions is calculated using the above formula 10; here, the calculation is performed for the case where j is a dam particle and i is an explosive particle. After the contact judgment is carried out, when the reservoir water particles are contacted with the dam particles, the interaction force is calculated subsequently, and otherwise, no force is generated. Since it is possible that i is a dam and j is an explosive; it is also possible that i is an explosive and j is a dam, so that the determination is made twice, and the contact force is calculated each time the contact condition is satisfied.

The contact judgment algorithm flow is as follows:

(1) in the particle modeling stage, designating a material range, dividing the material range into a dam particle region, an explosive particle region, a water pressure particle region and a pressurizing particle region, and endowing particle density, elastic modulus, strength parameters and the like of each region, and endowing particle type attribute values of each region to facilitate subsequent contact judgment; the initial value of xi is 1;

(2) breaking contact judgment, the specific judgment is described in the above "breaking contact judgment method";

(3) performing the contact force (stress) calculation of the current dam particles;

for other three material particles except the dam particles, the contact force such as water pressure, lifting force, explosion pressure and the like is not calculated among the particles with the same attribute, namely the contribution of external force to stress is 0; calculating a contact force, such as the contact of the dam particles and the explosive particles, according to the contact type based on the step 2-2 for materials with different properties, and then calculating a stress component to the dam particles generated by the explosion pressure by adopting a formula (formula 10) that the explosion pressure is converted into stress; if the dam particles are in contact with the reservoir water particles, calculating a stress component on the dam particles generated by the water pressure by adopting a formula (formula 6) of converting the water pressure into stress; if the dam particles are in contact with the winnowing force particles (formula 8), calculating the stress component of the winnowing force on the dam particles by adopting a formula of converting the winnowing force into stress; if the dam particles are in contact with the dam particles, adopting constitutive equation to calculate;

(4) After the stress is calculated, determining whether the current dam particles are broken and damaged and the type of the broken by a broken and damaged criterion, and correspondingly determining whether the broken shielding mark xi is changed to 0, wherein the interaction force is not calculated between the damaged particles and the intact particles in the subsequent calculation;

(5) for the current dam particles, the fracture shielding marks zeta and the contact stress values are brought into 11 and 12 to be calculated, and then information such as stress, strain, acceleration, speed, displacement and the like of the particles is solved.

And then cycling (2) (3) (4) until all dam particles have been traversed.

Step 2-4, simulating concrete fracture expansion;

taking the characteristic information and the xi value obtained by calculating the current time step as initial values for calculating the next time step; repeating the above process until reaching the preset time step number; and simulating the crack expansion condition of the concrete dam through the characteristic information of each dam particle at different time steps.

In the embodiment, the number of the damaged particles under each damage type is counted in each time step to obtain the time-dependent change condition of the total number of the damaged particles under each damage type, so that the damage evolution process of the concrete dam under the action of explosion load is respectively quantized and evaluated in a classified manner; and summing the numbers of the damaged particles under all the damage types in each time step to obtain the time-dependent change condition of the total number of the damaged particles of the concrete dam, thereby comprehensively quantifying and evaluating the damage evolution process of the concrete dam under the action of explosion load.

Step 4, post-processing visualization;

the field variable information such as stress, strain, displacement, speed, acceleration and the like of each particle is calculated and obtained through a smooth particle fluid dynamics method, the obtained information is digital text information, and the digital text information is converted into binary VTK file to be output and visualized. The particle output of different partitions is controlled by particle types, so that the material output classification can be realized, and finally, binary files containing dams, explosives and boundary particles can be respectively output, and the files can be displayed in some general open source software such as Paraview.

The method of the invention is characterized by comprising the following steps of verifying rationality, namely simulating and verifying uniaxial compression crack growth, simulating and verifying experimental crack growth under the action of explosion load, performing three-dimensional high-fidelity modeling on the concrete dam, and quantifying crack growth and damage of the dam.

As shown in FIG. 9, the crack propagation condition of the concrete sample under uniaxial compression obtained by calculation and simulation of the method is compared with the actual measurement result, so that the crack propagation form is consistent with the actual measurement result, and the method has the advantages that the predicted crack propagation direction is accurate, the accurate predicted crack propagation path and crack positioning can be realized, and reliable data can be provided for carrying out danger removal and reinforcement on a crack region in a later engineering.

As shown in fig. 10, the method calculates the simulated crack growth process and damage area distribution condition of the sample under the action of the explosion load and the maximum principal stress distribution condition of the sample under the action of the explosion load; FIG. 11 is a concrete dam high-fidelity model constructed by the method of the invention, no grid is needed, and the accuracy can reach the centimeter level; FIG. 12 is a graph showing the crack propagation process of a concrete dam under the combined action of simulated water pressure, lifting force and explosion load calculated by the method of the invention; fig. 13 shows real-time statistics of concrete dam damage under the combined action of reservoir water load, lifting force and explosion load. The simulation calculation results show that the invention can accurately and intuitively quantify the damage process, the crack extension process and the damage condition and obtain high-precision simulation results.

Through the above data, the accuracy, reliability and robustness of the present invention are demonstrated. The method can accurately calculate the crack propagation path, and is suitable for solving the problems of real-time accurate identification and positioning of the damage inside the concrete dam under the action of explosion load; the real-time statistics of the damage inside the dam body is realized, and the method can be used for solving the problems of real-time quantification and evaluation of the damage inside the concrete dam under the action of explosion load; and the method does not need to use grids, and is suitable for solving the problem of fine and high-fidelity modeling of the concrete dam in centimeter level. In addition, the invention can consider the spatial distribution non-uniformity of the aggregate and other materials of the concrete dam, and carry out uncertainty surface pointing on the strength parameters of the concrete dam, and the built model is more practical and can evaluate the crack propagation path more accurately.

< example two >

The second embodiment provides a real-time positioning and damage quantifying system capable of automatically realizing the concrete dam crack expansion under the explosion load of the method, which comprises a preprocessing part, a numerical simulation frame construction part, a quantifying evaluation part, an early warning part, an input display part and a control part.

The preprocessing part is used for executing the content described in the step 1, and the three-dimensional solid model of the concrete dam is built through modeling software and further is discretized into equidistant particle models.

The numerical simulation frame construction part is used for executing the content described in the step 2, and constructing the numerical simulation frame under the action of explosion load based on the equidistant particle model. The device comprises a setting unit, a contact force conversion unit, a judgment solving unit and a fracture expansion simulation unit. The setting unit is used for executing the content described in the step 2-1, selecting a linear elastic solid constitutive equation as a dam particle constitutive model, and setting a fracture failure criterion of the dam particles; the contact force conversion unit is used for executing the content of the step 2-2, and converting the contact force interacted by the particles of different materials into stress; the judging and solving unit is used for executing the content described in the step 2-3, and judging the fracture and damage of the dam particles and solving the characteristic information; the fracture expansion simulation unit is used for executing the content described in the step 2-4, and performing concrete fracture expansion simulation.

The quantitative evaluation part is used for executing the content described in the step 3, obtaining the damage types of the damage particles and the number of the damage particles corresponding to each damage type based on the numerical simulation framework, thereby determining the damage types in real time, and classifying and quantifying and evaluating the damage evolution process of the concrete dam under the action of explosion load in real time.

The early warning part is used for carrying out real-time early warning on dam damage according to the real-time quantification and the estimated concrete dam damage evolution process under the action of the explosion load of the safety threshold and the quantification estimating part.

The input display unit allows an operator to input an operation instruction, and can display input, output, and intermediate processing information of each unit according to the operation instruction.

The control part is communicated with the preprocessing part, the numerical simulation frame construction part, the quantitative evaluation part, the early warning part and the input display part, and controls the operation of the preprocessing part, the numerical simulation frame construction part, the quantitative evaluation part, the early warning part and the input display part.

The above embodiments are merely illustrative of the technical solutions of the present invention. The method and system for real-time positioning and damage quantification of concrete dam crack propagation under explosive load according to the present invention are not limited to the above embodiments, but the scope of the invention is defined by the claims. Any modifications, additions or equivalent substitutions made by those skilled in the art based on this embodiment are within the scope of the invention as claimed in the claims.

Claims

1. The method for real-time positioning and damage quantification of the crack extension of the concrete dam under the explosive load is characterized by comprising the following steps:

the water pressure and the lifting pressure are treated as a layer of mechanical boundary containing pressure information, a layer of particles is adopted to characterize the property of the pressure information, and the upstream water level difference is set as H _w The water pressure distributed along the upstream dam face of the concrete dam is P _w The elevating force distributed along the bedrock surface is U _w The explosion pressure is P _E The method comprises the steps of carrying out a first treatment on the surface of the The dam particles, the reservoir water particles, the explosive particles and the elevating force particles are endowed with different particle type values for distinguishing; the reservoir water particles and the lifting pressure particles are all single layers;

wherein, the step 2-1 and the step 2-2 have no sequence;

Step 2-4, simulating concrete fracture expansion;

2. The method for real-time positioning and damage quantification of crack propagation of concrete dam under explosive load according to claim 1, wherein the method comprises the following steps:

in the step 2-3, taking the actions of water pressure, lifting force and explosion load into consideration, introducing a fracture shielding mark xi to represent the particle state, and bringing the stress calculated in the step 2-2 into the following formula to solve the characteristic information of the dam particle i:

wherein: t is the calculation time; m is mass; v is the velocity of the dam particles; x is the position coordinates of the particle; t is an artificial sticky term; w is a smooth kernel function; delta and beta refer to vector directions of stress, the stress is a third-order tensor, and delta and beta can respectively take three directions of 1,2 and 3; taking dam i particles as the center, surrounding N particles, wherein j is marked as dam particles, explosive particles, reservoir water particles or elevating pressure particles; Stress of j particles to i particles, +.>The stress of the i particles to the j particles is that the j particles and the i particles are dam particles; />In the case of the existence of water particles in the influence domain, the water pressure P generated by the water particles _W Stress on the j particles; />In the case of the existence of the winnowing pressure particles in the influence domain, the winnowing pressure U generated by the winnowing pressure particles _W Stress on the j particles; />In order to influence the explosive pressure P generated by the explosive particles in the presence of the explosive particles in the domain _E Stress on the j particles.

3. The method for real-time positioning and damage quantification of crack propagation of concrete dam under explosive load according to claim 1, wherein the method comprises the following steps:

in step 2-3, the contact judgment between the dam particles i and other particles is specifically: taking the current dam particle i as a center, setting the particle radius as r, wherein the influence area of the dam particle i is f times the radius range of the surrounding area, f is more than or equal to 2, and if particles exist in the influence area, the contact action with the dam particle i is divided into four types, namely the contact with the same type of dam particles, the contact with reservoir water particles, the contact with the elevating pressure particles and the contact with explosive particles, and judging the contact type through a particle type value;

if the dam particles are judged to be in contact with the reservoir water particles, calculating stress by adopting a formula 2-2-1; if the dam particles are judged to be in contact with the lifting pressure particles, calculating stress by adopting a formula 2-2-2; if the dam particles are judged to be in contact with the explosive particles, calculating stress by adopting the formula 2-2-3; if the dam particles are judged to be in contact with the dam particles, the stress is calculated by the constitutive equation.

4. The method for real-time positioning and damage quantification of crack propagation of concrete dam under explosive load according to claim 1, wherein the method comprises the following steps:

in step 2-3, if the current dam particle i is determined to be broken and destroyed, and ζ=0, shielding the channel of the information communication between the dam particle i and surrounding particles, and not calculating the contact force between the dam particle i and other particles in the influence domain, wherein the determination of the dam particle i is finished; and then carrying out fracture damage judgment on the next dam particles.

5. The method for real-time positioning and damage quantification of crack propagation of concrete dam under explosive load according to claim 1, wherein the method comprises the following steps:

wherein, in step 2-1, the fracture failure criterion is:

σ _f ＝σ _t (2-1-1)

In sigma _f And τ _f The maximum tensile stress and the shear stress of the imaginary damage surface of the dam; sigma (sigma) _t Is the tensile strength of the particle; c is the cohesion of the particles;is the internal friction angle of the dam material; sigma (sigma) _t 、c、σ _f All are obtained according to the stress state of the dam particles i; when the dam particles i satisfy the tensile failure condition of the formula 2-1-1, judging that the particles are tensile-broken; when the formula 2-1-1 is not satisfied, the shear failure is judged by the formula 2-1-2, and if the dam particle i satisfies the formula 2-1-2, the shear failure is judged to occur in the particle.

6. The method for real-time positioning and damage quantification of crack propagation of concrete dam under explosive load according to claim 1, wherein the method comprises the following steps:

in the step 3, counting the number of damaged particles under each damage type in each time step to obtain the time-dependent change condition of the total number of the damaged particles under each damage type, thereby classifying, quantifying and evaluating the concrete dam damage evolution process under the action of explosion load respectively; and summing the numbers of the damaged particles under all the damage types in each time step to obtain the time-dependent change condition of the total number of the damaged particles of the concrete dam, thereby comprehensively quantifying and evaluating the damage evolution process of the concrete dam under the action of explosion load.

7. The method for real-time positioning and damage quantification of crack propagation of a concrete dam under explosive load according to claim 1, further comprising:

and 4, selecting proper materials for reinforcing and simulating corresponding crack areas of the concrete dam according to the damage degree of the concrete dam under different damage types positioned and quantified in the step 3 and aiming at the corresponding damage types and damage degrees.

8. The method for real-time positioning and damage quantification of crack propagation of concrete dam under explosive load according to claim 1, wherein the method comprises the following steps:

Wherein in step 2-2, the pressure P generated by the explosion of the explosive material _E The following formula is adopted for calculation:

9. Concrete dam crack extension real-time positioning and damage quantization system under explosion load, its characterized in that includes:

The judging and solving unit is used for judging the fracture and damage of the dam particles and solving the characteristic information; firstly, carrying out contact judgment on the current dam particle i and all other N particles in the influence domain of the dam particle i, calculating stress among corresponding material particles according to the step 2-2 after judging that the current dam particle i is in contact, otherwise, carrying out traversal to obtain stress caused by other N particles received by the dam particle i, accumulating the stress to obtain stress state information of the dam particle i, determining whether the dam particle i is broken and damaged according to the stress state information by a breaking and damage criterion, changing the value of a breaking shielding mark xi to be xi=0 when the particle is broken and damaged, marking the dam particle as damaged particle, otherwise, xi=1, and finally solving characteristic information of the dam particle i according to the breaking shielding mark xi and the stress received by the dam particle i; repeating the process for each dam particle to be simulated until all the dam particles to be simulated are traversed;

10. The concrete dam crack propagation real-time locating and damage quantifying system according to claim 9, further comprising:

the early warning part is in communication connection with the control part and carries out real-time early warning on the damage of the concrete dam according to the safety threshold value and the damage evolution process of real-time quantification and evaluation of the quantification evaluation part;

and the input display part is communicated with the control part, and allows an operator to input an operation instruction and display the operation instruction correspondingly.