CN100575924C - Non-destructive health detecting method for large structural matter - Google Patents

Abstract

The present invention is a non-destructive health detecting method for large structural matter, and its step has: storing step; The identification positioning step; The degree of injury appraisal procedure; Compare determining step.Can monitor out the works damage position effectively and the correctness of hindering the result is examined in checking according to this method.Using structure tension and compression modal strain energy in this detection method examines and hinders index (AMSECR); And/or the structure bending mode strain energy examines and hinders index (TMSECR), calculates and examines the numerical value of hindering index: thus STRUCTURE DAMAGE LOCATION is determined in diagnosis.Determine to hinder index value according to examining of calculating, according to SD in the process of degree of injury in diagnosis _j〉=-1, determine structural damage degree; Further definite works safety/or dangerous.The present invention proposes to be applicable to the large scale structure method of monitoring in real time, be used to set up the works health monitoring systems, improve the fatigue lifetime of works and the viability under the very big environmental load, to reach security, the economy that improves works and the operating personnel is had a sense of security.

Description

Non-destructive health detecting method for large structural matter

Technical field

The present invention relates to the improvement of large scale civil engineering structure thing health monitoring systems, specifically is a kind of non-destructive health detecting method for large structural matter.It is primarily aimed at complicated large scale civil engineering structure things such as ocean platform, under the environmental load excitation, utilizes dynamic test that structure is carried out lossless detection method.The present invention proposes to be applicable to the real-time damage diagnosis methods of monitoring of large scale structure such as ocean platform, be used to set up structural healthy monitoring system, improve the fatigue lifetime of structure and the viability under the very big environmental load, to reach security, the economy that improves structure and the operating personnel is had a sense of security.

Background technology

As everyone knows, the not Easy Test of environmental excitation power obtains, and is very crucial based on the diagnosing structural damage technology under the environmental load effect for the real-time monitoring structural health conditions of ocean platform therefore.Manually applying exciting force needs a large amount of specialized equipments and makes that test is very expensive for large scale civil engineering structure.In addition, large structure damages unavoidably during one's term of military service at it.The offshore platform structure long service and is subjected to reciprocation as various load such as wind load, seaway load, ice loads in abominable marine environment, also be in for earthquake, typhoon, tsunami, ship sometimes and unexpected the strike such as bump.Offshore platform structure itself also will suffer environmental corrosion, and foundation soil such as washes away at the effect of influence, its complex structure, involves great expense.In case have an accident, not only can cause very big pollution to marine environment, also can bring immeasurable economic loss and casualties, cause bad society and politics influence.Usually the damage of large structure is inevitable in structure during one's term of military service.But, being life security, the minimizing property loss of guaranteeing personnel, unique method is a structural damage of diagnosing out works early, and can in time carry out repair.Because the use of offshore platform structure can not be interrupted and expensive cost, the safety assessment of existing structure should be the method for harmless or little damage, and range estimation is usually used lossless detection method, and for the damage as the member fracture, range estimation can be judged damage.Yet the damage that causes for material aging, damage are in zone that can not be close or to be covered with by paint, rust and sea life be to be difficult to utilize range estimation to detect damage, are insecure so utilize range estimation to carry out Non-Destructive Testing.If modal parameter is by the identification down of environmental load incentive condition, be employed based on the damage diagnosis method of this technology is easier, develop long-range, structural healthy monitoring system will be feasible automatically, but the structural modal vibration shape that obtains under this condition is can't quality normalized, and for the such labyrinth of ocean platform, single damage criterion damage position accurately location is to realize.Other Dynamic Non-Destruction Measurement also belongs to the structure partial damage detecting method as methods such as X-ray check, Ultrasonic Detection, industry CT.It is known that this class technology only is used for damage field, even environmental load excitation modal parameter down can be discerned, the modal parameter that identifies can't quality normalization, and therefore, it is inapplicable that the examining of mostly present developmental research hindered algorithm.In addition, these technology also require special testing apparatus and professional.Therefore, these methods are inconvenient for the Non-Destructive Testing of offshore platform structure and are expensive.

Summary of the invention

From the literature review of the structure lossless detection method that changes based on structural dynamic characteristic, can see that there is the limitation of some practical applications in most methods, need the normalized vibration shape of quality, and the modal parameter of complete modal information, high-order or the like.The present invention is directed to above-mentioned limitation, propose new goal of the invention and be: use modal strain energy and decompose lossless detection method.Propose the damage positioning index, do not need the normalized vibration shape of quality, utilize first three rank Mode Shape of structural damage front and back to get final product.In addition, modal strain energy decomposition method of the present invention is examined and is hindered the material behavior that index need not known structure itself, only needs the topology information between the structural elements connection.Method of the present invention will be used under the multiple damage operating mode, and can accurately orient the damage position of offshore platform structure, makes method of the present invention have actual application value.

The present invention is based on a typical offshore platform structure or other three-dimensional frame structure, and its main member is by pile element, and horizontal brace member and diagonal supporting member are formed.When the mode of considering only is based on level or lateral vibration, rather than up and down (vertically) vibrate, then the modal strain energy of pile element will be to be changed to the master with the mode of flexural vibration strain energy.In other one side, the modal strain energy of horizontal brace member will be to be changed to the master with the tension and compression modal strain energy.When the loss of the stiffness of structural member of an offshore platform structure, will reduce corresponding to this member matrix element value of structural entity stiffness matrix.Corresponding, near the Mode Shape the degree of freedom of link will have significant variation.Because these nodes are with the damage member and do not damage member and be connected, so component damage causes that it will be not only damage member itself that the unit modal strain energy changes, and also will comprise these and damage the member that member links to each other thus.

Task of the present invention is finished by following technical scheme, has developed a kind of non-destructive health detecting method for large structural matter, and described detection method is based on large structure existing structure kinematic behavior and the method implemented, and it comprises the steps:

(1) storing step: at first, with the structure of said structure thing not under the environmental excitation under the faulted condition structural dynamic response data storage go in the private memory; Secondly, under the existing structure power faulted condition with the said structure thing, the structural dynamic response data storage that is about to the environmental excitation lower sensor actual measurement in structure military service stage is gone in the private memory;

(2) identification positioning step:. utilize natural excitation technique to identify the forward and backward modal parameter of said structure thing structural damage, determine the position that the structural elements damage occurs;

Promptly at first, modal parameter is expanded rank, secondly, use the degree of freedom cohesion of finite element model the sensor actual measurement; Once more, carry out structural environment excitation Modal Parameter Identification down: use the structural elements damage position that the modal strain energy decomposition method is diagnosed the said structure thing;

(3) degree of injury appraisal procedure: utilize natural excitation technique to identify the forward and backward modal parameter of said structure thing structural elements damage, utilize structure tension and compression modal strain energy change indicator and/or structure bending mode strain energy change indicator, analysis and evaluation said structure thing structural damage degree;

(4) compare determining step: according to above-mentioned (1)---(3) step, determine that the evaluation index numerical value of the degree of injury of said structure thing structural elements exists :-1≤SD _jIn≤0 scope, SD in the formula _jThe degree of injury of expression structural elements.

The position of using modal strain energy decomposition method deagnostic structure component damage in described (2) identification positioning step is to utilize structure tension and compression modal strain energy to change, that is:

1), utilization structure tension and compression modal strain energy is examined and is hindered index: $Z_j^a=\frac{{\mathrm{\β}}_j^a-\stackrel{\‾}{{\mathrm{\β}}^a}}{{\mathrm{\σ}}_{{\mathrm{\β}}^a}}$ 1. structure tension and compression modal strain energy is changed in the formula: ${\mathrm{\β}}_j^a=\underset{i=1}{\overset{N_m}{\mathrm{\Σ}}}\frac{({{\mathrm{\Φ}}_i^{*}}^T{K}_{j0}^a{\mathrm{\Φ}}_i^{*}+{{\mathrm{\Φ}}_i^{*}}^T{K}_0^a{\mathrm{\Φ}}_i^{*}){{\mathrm{\Φ}}_i}^T{K}_0^a{\mathrm{\Φ}}_i}{({{\mathrm{\Φ}}_i}^T{K}_{j0}^a{\mathrm{\Φ}}_i+{{\mathrm{\Φ}}_i}^T{K}_0^a{\mathrm{\Φ}}_i){{\mathrm{\Φ}}_i^{*}}^T{K}_0^a{\mathrm{\Φ}}_i^{*}}$ 2. Φ in the formula _i,

Wherein subscript " T " refers to transposition, K _J0=K _j/ E _jAnd K _j=j does not damage the unit system stiffness matrix, K ₀ ^aBe by cell matrix K _J0 ^aThe system matrix that assembles; β _j ^aAlso represent E _j/ E _j ^*Ratio, E _j, E _j ^*Each represents the elastic modulus of the structural elements after structure is not damaged and damaged, and estimates the damage position of the structural elements of said structure thing; And/or

2), utilization structure mode of flexural vibration strain energy is examined and is hindered index: $Z_j^t=\frac{{\mathrm{\&beta;}}_j^t-\stackrel{\&OverBar;}{{\mathrm{\&beta;}}^t}}{{\mathrm{\&sigma;}}_{{\mathrm{\&beta;}}^{\mathrm{<figure-callout\; id="3"\; label="t"\; filenames="C2005100445760010H5.png,C2005100445760010H6.png"\; state="\{\{state\}\}">t</figure-callout>}}}}$ 3. the structure bending mode strain energy is changed in the formula; ${\mathrm{\&beta;}}_j^t=\underset{i=1}{\overset{\mathrm{NM}}{\mathrm{\&Sigma;}}}\frac{({{\mathrm{\&Phi;}}_i^{*}}^T{K}_{j0}^t{\mathrm{\&Phi;}}_i^{*}+{{\mathrm{\&Phi;}}_i^{*}}^T{K}_0^t{\mathrm{\&Phi;}}_i^{*}){{\mathrm{\&Phi;}}_i}^T{K}_0^t{\mathrm{\&Phi;}}_i}{({{\mathrm{\&Phi;}}_i}^T{K}_{j0}^t{\mathrm{\&Phi;}}_i+{{\mathrm{\&Phi;}}_i}^T{K}_0^t{\mathrm{\&Phi;}}_i){{\mathrm{\&Phi;}}_i^{*}}^T{K}_0^t{\mathrm{\&Phi;}}_i^{*}}$ 4. Φ in the formula _i,

Wherein subscript " T " refers to transposition, K _J0=K _j/ E _jAnd K _j=j does not damage the unit system stiffness matrix, K ₀ ^tBe by cell matrix K _J0 ^tThe system matrix that assembles; β _j ^tAlso represent E _j/ E _j ^*Ratio, E _j, E _j ^*Each represents the elastic modulus of the structural elements after structure is not damaged and damaged, and estimates the damage position of the structural elements of said structure thing.

Analysis and evaluation structural damage degree in described (3) degree of injury appraisal procedure is the structure tension and compression modal strain energy change indicator that utilizes the said structure thing, promptly ${\mathrm{SD}}_j={\mathrm{\&alpha;}}_j^a=\frac{{E_j^a}^{*}-E_j^a}{E_j^a}=\frac{1}{{\mathrm{\&beta;}}_j^a}-1$ 5. SD in the formula _j〉=-1, estimate the degree of injury of the structural elements of said structure thing; And/or utilize the structure bending mode strain energy change indicator of said structure thing, promptly ${\mathrm{SD}}_j={\mathrm{\&alpha;}}_j^t=\frac{{E_j^t}^{*}-E_j^t}{E_j^t}=\frac{1}{{\mathrm{\&beta;}}_j^t}-1$ 6. SD in the formula _j〉=-1, estimate the degree of injury of the structural elements of said structure thing;

Determine the degree of injury judge index of the structural elements of said structure thing: if SD _j=0, then represent the not damage of j cellular construction member of said structure thing; If SD _j=-1, represent that then the rigidity of the j cellular construction member of said structure thing completely loses; The degree of injury evaluation index numerical value of promptly determining structural elements exists :-1≤SD _jIn≤0 scope.

Structural dynamic response data under the environmental excitation of described structured design phase, itself or acceleration, and/or be speed, and/or be displacement, and/or be elastic modulus.

The be on active service structural dynamic response data of environmental excitation lower sensor actual measurement in stage of described structure, itself or acceleration, and/or be speed, and/or be displacement, and/or be elastic modulus.

The advantage of the modal strain energy decomposition method that the present invention proposes is: since two indexs of examining wound for: if horizontal brace or diagonal supporting member have damaged, the tension and compression modal strain energy of support member is examined and is hindered index and will change maximum, and the mode of flexural vibration strain energy desired value of the pile element that links to each other with the damage unit will change bigger; If vertical pile element has damaged, the mode of flexural vibration strain energy desired value of pile element will change bigger, and the tension and compression modal strain energy desired value of the support member that links to each other with pile element will change bigger.Around this principle can effectively monitor out the damage position and the further checking of structure and examine the correctness of hindering the result.

It is of the present invention that power under the large structure environmental excitation is examined the bleeding journey is as follows:

1), storing step: with works not under the faulted condition under the environmental excitation structural dynamic response data storage go in the private memory; When works is on active service the stage, structural dynamic response data under the environmental excitation under the structural damage state also are stored in this private memory again;

2) it is rapid that, parameter expands step: the modal parameter under the works environmental excitation is carried out modal parameter expand rank;

3), the identification step of the model frequency and the vibration shape: the modal parameter that the parameter under the works environmental excitation is expanded rank carries out the identification of the model frequency and the vibration shape;

4), determine whether damage step occurs: the modal parameter that the comparative structure thing damages after preceding and the damage changes, and determines whether structural damage occurs, even damage, or does not damage;

5), calculating is examined and hindered the index step: application structure tension and compression modal strain energy is examined and is hindered index (AMSECR); And/or the structure bending mode strain energy examines and hinders index (TMSECR), calculates to examine and hinders index (AMSECR) and/or numerical value (TMSECR); STRUCTURE DAMAGE LOCATION is determined in diagnosis;

6), the degree of injury step is determined in diagnosis: examine according to calculating and hinder index (AMSECR) and/or numerical value (TMSECR), structural damage degree is determined in diagnosis;

7), determine whether security step of structure: according to SD _j〉=-1, determine structural safety/or dangerous;

8), further examine in detail and hinder step: as the case may be, further structure is examined wound in detail.

Accompanying drawing and embodiment thereof

Embodiments of the invention further specify as follows in conjunction with the accompanying drawings:

Fig. 1 is: enforcement offshore platform structure finite element model figure of the present invention.

Fig. 2 is: index curve map (operating mode A) is hindered in axially examining of enforcement offshore platform structure of the present invention.

Fig. 3 is: index curve map (operating mode A) is hindered in laterally examining of enforcement offshore platform structure of the present invention.

Fig. 4 is: the index Z of enforcement offshore platform structure of the present invention _j ^aCell position synoptic diagram (operating mode A).

Fig. 5 is: the index Z of enforcement offshore platform structure of the present invention _j ^tCell position synoptic diagram (operating mode A).

Fig. 6 is: index curve map (operating mode B) is hindered in axially examining of enforcement offshore platform structure of the present invention.

Fig. 7 is: the bending of enforcement offshore platform structure of the present invention is examined and is hindered index curve map (operating mode B).

Fig. 8 is: the index Z of enforcement offshore platform structure of the present invention _j ^aCell position synoptic diagram (operating mode B).

Fig. 9 is: the index Z of enforcement offshore platform structure of the present invention _j ^tCell position synoptic diagram (operating mode B).

Figure 10 is: index curve map (operating mode C) is hindered in axially examining of enforcement offshore platform structure of the present invention.

Figure 11 is: the bending of enforcement offshore platform structure of the present invention is examined and is hindered index curve map (operating mode C).

Figure 12 is: the index Z of enforcement offshore platform structure of the present invention _j ^aCell position synoptic diagram (operating mode C).

Figure 13 is: the index Z of enforcement offshore platform structure of the present invention _j ^tCell position synoptic diagram (operating mode C).

Figure 14 is: diagnosis of complex three-dimensional structure damage schematic flow sheet of the present invention.

Specific embodiment is as follows, and protection scope of the present invention not only is confined in following examples.

One, set up the ocean platform finite element numerical model:

Embodiments of the invention are modeling effories, and offshore platform structure is positioned at depth of water 97.4m, and structure is made up of vertical stake, horizontal brace and diagonal supporting member, and totally 207 unit are seen shown in Figure 1.Utilize commercial finite element software (275 Technology Drive, Canonsburg, PA 15317. for Ansys Version7.0, ANSYS Inc.) to produce the dynamic response data of simulation.The acceleration transducer that the present invention adopts, its model: U.S. SILICON DESIGNS company produces Model2220-005.In addition, adopted data collecting instrument, its model: the integrated observing and controlling of German Imc company limited produces PL16-DCB8.Buildings on this outer platform is simulated with mass unit, has also used several special structural units, comprises simulation marine environment load, as wave, and stream, additional mass etc.

Two, damage analysis:

The finite element model that the front is introduced is as a benchmark model.For the ease of examining the explanation of hindering the result, each unit of offshore platform structure indicates with a number.Present embodiment has been simulated three kinds of typical damage operating modes, comprises the horizontal brace component damage, diagonal supporting member and pile element damage.Concrete damage operating mode is shown in Table 1.

Table 1 Simulation Damage operating mode:

The damage operating mode	The damage member	Unit number	The stiffness of structural member reduction
				A	Horizontal brace	14	5％
B	Diagonal brace	105	5％
				C	Pile element	78&79	10％

1) damage operating mode A---horizontal brace component damage: what first damaged Work condition analogue is unit 14 losss of rigidity 5%; The utilization modal strain energy decomposition method that this paper carried: provided among Fig. 2 axially to examine and hindered desired value Z _j ^aFig. 3 has provided laterally to examine and has hindered desired value Z _j ^tFrom Fig. 2, Fig. 3, Fig. 4 easily sees among Fig. 5, index Z is hindered in examining of horizontal brace member 14 and diagonal supporting member 106 (its position view is seen Fig. 4) _j ^aBigger, so these two members may be the damage unit.Similar therewith, pile element 79,78 and 55 (its position view is seen Fig. 5) also is the unit member that possible damage.If pile element has damaged, near the Z of the horizontal brace/diagonal supporting member this member so _j ^aDesired value is bigger, and is apparent, is not such among Fig. 2.In other one side, if horizontal brace member 14 has damaged, near the support member it is as 79,78, and desired value Z is hindered in 55 laterally examine _j ^tBigger.Therefore, the horizontal brace unit 14 of can reaching a conclusion has damaged.

2) damage operating mode B---diagonal supporting member damage: second damage Work condition analogue be unit 105 losss of rigidity 5%; Axially examine and hinder index Z _j ^aAnd laterally examine and hinder desired value Z _j ^t, be presented at Fig. 6 and Fig. 7 respectively.From Fig. 6, may there be damage in diagonal supporting member 105 and 106 as can be seen, (its position view such as Fig. 8).In like manner, in Fig. 7, easy analysis draws plumb pile unit 56 and 80 and may have damage (its position view such as Fig. 9).If the damage unit is pile element 56 or 80, near the diagonal brace it and the Z of horizontal brace member _j ^aDesired value inevitable bigger, but from Fig. 6, easily see and do not exist. Diagonal brace unit 105 or 106 has damaged, near the pile element 56,80 it, Z _j ^tDesired value is bigger, so the possibility of these two component damages is bigger.Since unit 105, Z _j ^tDesired value is big than unit 106, so can be sure of unit 105 damage has taken place.

3) damage operating mode C---vertical pile element damage: what the third damaged Work condition analogue is pile element unit 78 and unit 79 losss of rigidity 10%; Examine and hinder desired value Z _j ^tAnd Z _j ^tAt Figure 10 and shown in Figure 11.As seen from Figure 10: diagonal supporting member 94 and 96 (its position view sees 12) has bigger Z with some other member _j ^aThis shows that also this desired value only plays a booster action for the identification of damage unit.Hinder desired value Z from examining _j ^t, see that easily vertical pile element unit 78 and 79 may be damage unit (its position view is seen Figure 13).Hinder ultimate principle according to examining of introducing previously, be not difficult to infer that unit 78 and 79 has damaged, and near the diagonal brace these two unit and the Z of horizontal brace member _j ^aExamine that to hinder desired value bigger.

Those of ordinary skill in the art can understand, and in protection scope of the present invention, makes amendment for the foregoing description, and it all is possible adding and replacing, and it does not all exceed protection scope of the present invention.

Claims (2)

1, a kind of lossless detection method based on large-scale existing structure thing kinematic behavior is characterized in that:

Described method comprises the steps:

(1) storing step: at first, with the said structure thing not under the faulted condition promptly the structural dynamic response data storage under the environmental excitation of structured design phase go in the private memory; Secondly, be that the structural dynamic response data storage that the sensor under the structure environmental excitation in military service stage is surveyed is gone in the private memory under the existing structure dynamic regime with the said structure thing;

(2) identification positioning step: utilize natural excitation technique to identify the forward and backward modal parameter of said structure thing damage, determine the position that the structural elements damage occurs;

Promptly at first, modal parameter is expanded rank; Secondly, use the degree of freedom cohesion of finite element model with the sensor actual measurement; Once more, carry out structural environment excitation Modal Parameter Identification down: use the concrete damage position that the modal strain energy decomposition method is diagnosed the said structure thing;

(3) degree of injury appraisal procedure: utilize structure tension and compression modal strain energy change indicator and structure bending mode strain energy change indicator, the degree of injury of analysis and evaluation said structure thing damage member;

(4) compare determining step:, determine that the evaluation index numerical value of said structure component of thing degree of injury exists :-1≤SD according to above-mentioned steps (3) _jIn≤0 scope, SD in the formula _jThe degree of injury of expression structural elements;

The damage position of using modal strain energy decomposition method deagnostic structure thing in described (2) identification positioning step is specially:

1), utilization structure tension and compression modal strain energy is examined and is hindered index: $Z_j^a=\frac{{\mathrm{\&beta;}}_j^a-\stackrel{\&OverBar;}{{\mathrm{\&beta;}}^a}}{{\mathrm{\&sigma;}}_{{\mathrm{\&beta;}}^a}}$ 1. structure tension and compression modal strain energy is changed in the formula: ${\mathrm{\&beta;}}_j^a=\underset{i=1}{\overset{N_m}{\mathrm{\&Sigma;}}}\frac{({{\mathrm{\&Phi;}}_i^{*}}^T{K}_{j0}^a{\mathrm{\&Phi;}}_i^{*}+{{\mathrm{\&Phi;}}_i^{*}}^T{K}_0^a{\mathrm{\&Phi;}}_i^{*}){{\mathrm{\&Phi;}}_i}^T{K}_0^a{\mathrm{\&Phi;}}_i}{({{\mathrm{\&Phi;}}_i}^T{K}_{j0}^a{\mathrm{\&Phi;}}_i+{{\mathrm{\&Phi;}}_i}^T{K}_0^a{\mathrm{\&Phi;}}_i){{\mathrm{\&Phi;}}_i^{*}}^T{K}_0^a{\mathrm{\&Phi;}}_i^{*}}$ 2. Φ in the formula _i, Φ _i ^*Refer to before the structural damage respectively and the Mode Shape after the damage, wherein subscript " T " refers to transposition, K _J0=K _j/ E _i, K wherein _jBe that the j unit does not damage system stiffness matrix, K _J0 ^aBe the tensile compressive stiffness matrix of j unit, K ₀ ^aBe by cell matrix K _J0 ^aThe tension and compression system matrix that assembles; β _j ^aAlso expression

Ratio, E _j ^a,

Each represents the structural elements elastic modulus after structure j unit does not damage and damages, and estimates the component damage position of said structure thing; With

2), utilization structure mode of flexural vibration strain energy is examined and is hindered index: $Z_j^t=\frac{{\mathrm{\&beta;}}_j^t-\stackrel{\&OverBar;}{{\mathrm{\&beta;}}^t}}{{\mathrm{\&sigma;}}_{{\mathrm{\&beta;}}^t}}$ 3. the structure bending mode strain energy is changed in the formula; ${\mathrm{\&beta;}}_j^t=\underset{i=1}{\overset{\mathrm{NM}}{\mathrm{\&Sigma;}}}\frac{({{\mathrm{\&Phi;}}_i^{*}}^T{K}_{j0}^t{\mathrm{\&Phi;}}_i^{*}+{{\mathrm{\&Phi;}}_i^{*}}^T{K}_0^t{\mathrm{\&Phi;}}_i^{*}){{\mathrm{\&Phi;}}_i}^T{K}_0^t{\mathrm{\&Phi;}}_i}{({{\mathrm{\&Phi;}}_i}^T{K}_{j0}^t{\mathrm{\&Phi;}}_i+{{\mathrm{\&Phi;}}_i}^T{K}_0^t{\mathrm{\&Phi;}}_i){{\mathrm{\&Phi;}}_i^{*}}^T{K}_0^t{\mathrm{\&Phi;}}_i^{*}}$ 4. Φ in the formula _i, Φ _i ^*Refer to before the structural damage respectively and the Mode Shape after the damage, wherein subscript " T " refers to transposition, K _J0=K _j/ E _j, K wherein _jBe that the j unit does not damage system stiffness matrix, K _J0 ^tBe the bending stiffness matrix of j unit, K ₀ ^tBe by cell matrix K _J0 ^tThe bending system matrix that assembles; β _j ^tAlso expression

Ratio, E _j ^t,

Each represents the structural elements elastic modulus after structure j unit does not damage and damages, and estimates the component damage position of said structure thing; β ^a, β ^tBe corresponding index β ^aAnd β ^tAverage,

Be meant standard variance;

The analysis and evaluation structural damage degree is in described (3) degree of injury appraisal procedure, utilizes the tension and compression modal strain energy change indicator of said structure thing

Promptly ${\mathrm{SD}}_j={\mathrm{\&alpha;}}_j^a=\frac{E_j^{a^{*}}-E_j^a}{E_j^a}=\frac{1}{{\mathrm{\&beta;}}_j^a}-1$ 5. SD in the formula _j〉=-1, estimate the component damage degree of said structure thing;

With

Utilize the mode of flexural vibration strain energy change indicator of said structure thing

Promptly ${\mathrm{SD}}_j={\mathrm{\&alpha;}}_j^t=\frac{E_j^{t^{*}}-E_j^t}{E_j^t}=\frac{1}{{\mathrm{\&beta;}}_j^t}-1$ 6. SD in the formula _j〉=-1, estimate the component damage degree of said structure thing;

Determine the component damage degree judge index of said structure thing: if SD _j=0, then represent the not damage of j cellular construction member of said structure thing; If SD _j=-1, represent that then the rigidity of the j cellular construction member of said structure thing completely loses; The degree of injury evaluation index numerical value of structural elements exists :-1≤SD _jIn≤0 scope.

2, according to the described lossless detection method based on large structure existing structure kinematic behavior of claim 1, it is characterized in that: structural dynamic response data under the environmental excitation of described structured design phase, it is an acceleration, or speed, or displacement.

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