CN105366026B - A kind of axis pressure Material Stiffened Panel post-buckling carrying design method - Google Patents
A kind of axis pressure Material Stiffened Panel post-buckling carrying design method Download PDFInfo
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- CN105366026B CN105366026B CN201510825123.3A CN201510825123A CN105366026B CN 105366026 B CN105366026 B CN 105366026B CN 201510825123 A CN201510825123 A CN 201510825123A CN 105366026 B CN105366026 B CN 105366026B
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Abstract
The invention discloses a kind of axis pressure Material Stiffened Panel post-bucklings to carry design method, belongs to field of airplane structure.The method includes pressing the sectional parameter of Material Stiffened Panel according to axis first, rib spacing b, muscle spacing a and skin thickness t presses the beginning buckling load of siding rib to calculate axis and calculates the breaking load of axis pressure siding rib, finally, calculate the ratio n of the breaking load and the beginning buckling load of axis pressure siding rib of axis pressure siding rib, and reset a, b and t values, until n meets preset value, to reach the efficient design to axis pressure Material Stiffened Panel post-buckling carrying, pass through this method, it can be designed that the highest metal shaft pressure siding of construction weight efficiency under bearing requirements；Half theoretical semiempirical formula of the design method combination Accurate Prediction bursting stress, using simple, conveniently.
Description
Technical field
The invention belongs to field of airplane structure, and in particular to a kind of axis pressure Material Stiffened Panel post-buckling carrying design side
Method.
Background technology
In airplane design technical field, buckling structure is one of sixty-four dollar question in aeroplane structure design, is held as master
The axis of power component presses Material Stiffened Panel, the quality of design to depend primarily on buckling design.
Composite Material Stiffened Panel is widely used as a kind of typical structure, however in real process, it will usually by
To the effect of the load such as compression, shearing, buckling failure is most common failure mode, and the Composite Material Stiffened Panel after buckling
With higher post-buckling bearing capacity, Material Stiffened Panel buckling is usually adopted in the prior art to the post-buckling state between destroying
With the semi-theoretical analysis method of semiempirical, the bursting stress of prediction and agreement with experimental data it is fine.But existing design method is not
It can determine when to start buckling, when destroy construction weight efficiency highest.
Invention content
To solve the above-mentioned problems, the present invention proposes a kind of axis pressure Material Stiffened Panel post-buckling carrying design method, mainly
Include the following steps：
S1, Material Stiffened Panel stand under load figure is drawn, and rib section shape is designed according to loading conditions, obtain the section ginseng
Number, the sectional parameter includes the moment of inertia and area of the section；
S2, according to the type of attachment and Material Stiffened Panel of rib and web in Material Stiffened Panel and the connection shape of peripheral structure
Formula determines that the boundary supports conditions of Material Stiffened Panel, the rib include several orthogonal lengthways of rod and lateral rib；
The spacing of S3, the spacing initial setting a for giving adjacent lengthways of rod and given adjacent transverse rib are initially set
Value b, while the thickness t of given covering are set, the skin thickness is the rib web thickness of the Material Stiffened Panel；
S4, the beginning buckling that axis presses siding rib is calculated according to the sectional parameter in step S1 and a, b value in step S3
Load；
S5, the breaking load that axis presses siding rib is calculated according to the sectional parameter in step S1, a, b value in step S3；
The ratio n of S6, the breaking load and the beginning buckling load of axis pressure siding rib for calculating axis pressure siding rib, and
A, b and t value are reset, step S3~S6 is repeated, until n meets preset value.
Preferably, the back of the breaking load for calculating axis pressure siding rib further includes calculating axis pressure siding rib
Euler's stress and axis pressure siding rib siding crushing intensity, the breaking load σ of axis pressure siding ribc0=[1- (1-
σcr/σf)(σcr/σe)]σf, wherein the σeEuler's stress of siding rib, σ are pressed for axisfThe wall of siding rib is pressed for the axis
Plate crushing intensity, σcrThe beginning buckling load of siding rib is pressed for the axis.
It is preferably in the above scheme, the back of the beginning buckling load for calculating axis pressure siding rib includes meter
Calculate the siding crushing intensity for stating axis pressure siding rib.
It is preferably in the above scheme, the Europe tensile stress sigma for calculating axis pressure siding ribe=C π2E/(L'/ρ)2,
Middle C is that coefficient is supported in Material Stiffened Panel end, and L is rib spacing, i.e. the spacing b of adjacent transverse rib,
I and A is respectively the moment of inertia and area of Material Stiffened Panel section.
It is preferably in the above scheme, the siding crushing intensity σ of the axis pressure siding ribf=σ0.2β[(fδt/F)
(E/σ0.2)(1/2)]0.4, wherein β is the pressure loss coefficient determined according to cutting number and flange number, and f cuts the sum of number and flange number, δ
Skin thickness, F are Material Stiffened Panel sectional area, σ0.2For the yield limit of material, E is the elasticity modulus of material.
It is preferably in the above scheme, the local buckling limit stress σ of the axis pressure siding ribcr=K π2Eδ2/[12
(1-μ2)a2], wherein K is that coefficient is supported on the boundary of reinforcement covering.
It is preferably in the above scheme, the preset value n is 1.5.
It is preferably in the above scheme, the obtaining value method of described a, b and t include keeping a, b value motionless, with particular step size
Increase x and increase the value of t, alternatively, keeping a, t value motionless, increases the value of b with particular step size x, alternatively, keeping b, t value motionless, with specific step
Long x increases the value of a.
It is preferably in the above scheme, the value of the x is 0.2mm.
It is an advantage of the invention that：
Meet axis pressure siding bearing requirements, i.e. ultimate load do not destroy, the requirement of limitation load not unstability；This method is not only
Suitable metal axis presses Material Stiffened Panel, is applicable in the thin-wall construction of related to Post-Buckling Analysis, the n in the above method is changed to
Required restrictive condition predicts that the parabolic formula of bursting stress and breaking load calculation formula can with technological progress
To be changed to more accurate formula；This method can be designed that the highest metal shaft pressure wall of the construction weight efficiency under bearing requirements
Plate；Half theoretical semiempirical formula of the design method combination Accurate Prediction bursting stress, using simple, conveniently.
Description of the drawings
Fig. 1 is the flow chart for the preferred embodiment that Material Stiffened Panel post-buckling carrying design method is pressed according to axis of the present invention.
Fig. 2 is that the axis of embodiment illustrated in fig. 1 presses Material Stiffened Panel structural schematic diagram.
Wherein, 1 is web, and 2 be lengthways of rod, and 3 be lateral rib.
Specific implementation mode
To keep the purpose, technical scheme and advantage that the present invention is implemented clearer, below in conjunction in the embodiment of the present invention
Attached drawing, technical solution in the embodiment of the present invention is further described in more detail.In the accompanying drawings, identical from beginning to end or class
As label indicate same or similar element or element with the same or similar functions.Described embodiment is the present invention
A part of the embodiment, instead of all the embodiments.The embodiments described below with reference to the accompanying drawings are exemplary, it is intended to use
It is of the invention in explaining, and be not considered as limiting the invention.Based on the embodiments of the present invention, ordinary skill people
The every other embodiment that member is obtained without creative efforts, shall fall within the protection scope of the present invention.Under
Face is described in detail the embodiment of the present invention in conjunction with attached drawing.
In the description of the present invention, it is to be understood that, term "center", " longitudinal direction ", " transverse direction ", "front", "rear",
The orientation or positional relationship of the instructions such as "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outside" is based on attached drawing institute
The orientation or positional relationship shown, is merely for convenience of description of the present invention and simplification of the description, and does not indicate or imply the indicated dress
It sets or element must have a particular orientation, with specific azimuth configuration and operation, therefore should not be understood as protecting the present invention
The limitation of range.
The structure of axis pressure Material Stiffened Panel of the present invention is as shown in Figure 2, wherein 1 is web, and 2 be lengthways of rod, and 3 is laterally
Rib.It should be noted that in Fig. 2, adjacent to the spacing of rib is a, and the spacing of adjacent transverse rib is b, the thickness of covering
For t.
In the present embodiment, axis presses Material Stiffened Panel post-buckling to carry design method, mainly includes the following steps that：
S1, Material Stiffened Panel stand under load figure is drawn, and rib section shape is designed according to loading conditions, obtain the section ginseng
Number, the sectional parameter includes the moment of inertia and area of the section；
S2, according to the type of attachment and Material Stiffened Panel of rib and web in Material Stiffened Panel and the connection shape of peripheral structure
Formula determines that the boundary supports conditions of Material Stiffened Panel, the rib include several orthogonal lengthways of rod and lateral rib；
The spacing of S3, the spacing initial setting a for giving adjacent lengthways of rod and given adjacent transverse rib are initially set
Value b, while the thickness t of given covering are set, the skin thickness is the rib web thickness of the Material Stiffened Panel；
S4, the beginning buckling that axis presses siding rib is calculated according to the sectional parameter in step S1 and a, b value in step S3
Load；
S5, the breaking load that axis presses siding rib is calculated according to the sectional parameter in step S1, a, b value in step S3；
The ratio n of S6, the breaking load and the beginning buckling load of axis pressure siding rib for calculating axis pressure siding rib, and
A, b and t value are reset, step S3~S6 is repeated, until n meets preset value.
Preferably, the back of the breaking load for calculating axis pressure siding rib further includes calculating axis pressure siding rib
Euler's stress and axis pressure siding rib siding crushing intensity, the breaking load σ of axis pressure siding ribc0=[1- (1-
σcr/σf)(σcr/σe)]σf, wherein the σeEuler's stress of siding rib, σ are pressed for axisfThe wall of siding rib is pressed for the axis
Plate crushing intensity, σcrThe beginning buckling load of siding rib is pressed for the axis.
It is preferably in the above scheme, the back of the beginning buckling load for calculating axis pressure siding rib includes meter
Calculate the siding crushing intensity for stating axis pressure siding rib.
It is preferably in the above scheme, the Euler's stress for calculating axis pressure siding rib:
σe=C π2E/(L'/ρ)2, wherein C is that coefficient is supported in Material Stiffened Panel end, and L is rib spacing, i.e. adjacent transverse rib
Spacing b,I and A is respectively the moment of inertia and area of Material Stiffened Panel section.
It is preferably in the above scheme, the siding crushing intensity of the axis pressure siding rib:
σf=σ0.2β[(fδt/F)(E/σ0.2)(1/2)]0.4, wherein β is the crushing system determined according to cutting number and flange number
Number, f cut the sum of number and flange number, δ skin thickness, and F is Material Stiffened Panel sectional area, σ0.2For the yield limit of material, E is material
The elasticity modulus of material.
It is preferably in the above scheme, local buckling's limit stress of the axis pressure siding rib:
σcr=K π2Eδ2/[12(1-μ2)a2], wherein K is that coefficient is supported on the boundary of reinforcement covering.
It is preferably in the above scheme, the preset value n is 1.5.
It is preferably in the above scheme, the obtaining value method of described a, b and t include keeping a, b value motionless, with particular step size
Increase x and increase the value of t, alternatively, keeping a, t value motionless, increases the value of b with particular step size x, alternatively, keeping b, t value motionless, with specific step
Long x increases the value of a.
It is preferably in the above scheme, the value of the x is 0.2mm.
Siding bearing requirements are pressed meeting axis, i.e. ultimate load do not destroy, the requirement of limitation load not unstability；This method is not
Only suitable metal axis presses Material Stiffened Panel, is applicable in the thin-wall construction of related to Post-Buckling Analysis, the n in the above method is changed
For required restrictive condition the parabolic formula and breaking load calculation formula of bursting stress are predicted with technological progress
It is readily modified as more accurate formula；This method can be designed that the highest metal shaft pressure of the construction weight efficiency under bearing requirements
Siding；Half theoretical semiempirical formula of the design method combination Accurate Prediction bursting stress, using simple, conveniently.
In the present embodiment, given parameters are as follows first：
Given initial value is as follows：Material Stiffened Panel safety coefficient n=1.5, Material Stiffened Panel design load P=580kN；Material：
Aluminium alloy, E=69GPa；
Geometric parameter：Rib spacing b=650mm, muscle spacing a=100mm, skin thickness t=2mm, 5 ribs are whole to add
Muscle siding, border coefficient K=6.1.
Above-mentioned parameter is substituted into formula respectively:
σc0=[1- (1- σcr/σf)(σcr/σe)]σf；
σe=C π2E/(L'/ρ)2；
σf=σ0.2β[(fδt/F)(E/σ0.2)(1/2)]0.4；
σcr=K π2Eδ2/[12(1-μ2)a2]。
It is obtained finally by above-mentioned：
Buckling load σcr=147MPa,
Material Stiffened Panel breaking load σc0=252MPa,
σc0/σcr=1.714 ＞ 1.5,
Skin thickness, t=2.2mm are adjusted by step-length of x=0.2mm, remaining parameter constant continues ratio calculated n；It can be with
Understand, x values here are determined on a case-by-case basis, for example, in the case of skin thickness 2.2, x is set as 5mm, that is, adjusts
Whole skin thickness t=2.2mm, rib spacing a=105mm, remaining parameter constant are calculated again：
Buckling load σcr=168MPa,
Material Stiffened Panel breaking load σc0=255MPa,
At this point, σc0/σcr=1.52, requirement is still not satisfied,
Consider public journey rounding and technique level of processing, finally obtains：Skin thickness t=2.2mm, rib spacing a=
105mm, rib spacing b=650mm, at this point, σc0/σcr=1.2, in the case where meeting the requirements, ratio is smaller, meets the requirements, together
When, the bearing capacity of siding at this time is obtained by further calculating：
P1=σc0A=584Kn meets intensity requirement, it is believed that in the case where other parameters are given, which weighs at this time
It measures optimal.
It is last it is to be noted that：The above embodiments are merely illustrative of the technical solutions of the present invention, rather than its limitations.To the greatest extent
Present invention has been described in detail with reference to the aforementioned embodiments for pipe, it will be understood by those of ordinary skill in the art that：It is still
Can be with technical scheme described in the above embodiments is modified, or which part technical characteristic is equally replaced
It changes；And these modifications or replacements, the essence for various embodiments of the present invention technical solution that it does not separate the essence of the corresponding technical solution
God and range.
Claims (9)
1. a kind of axis pressure Material Stiffened Panel post-buckling carries design method, which is characterized in that including：
S1, Material Stiffened Panel stand under load figure is drawn, and rib section shape is designed according to loading conditions, obtain the sectional parameter, institute
State the moment of inertia and area that sectional parameter includes the section；
S2, according to the type of attachment of rib and web in Material Stiffened Panel and the type of attachment of Material Stiffened Panel and peripheral structure, really
Determine the boundary supports conditions of Material Stiffened Panel, the rib includes several orthogonal lengthways of rod and lateral rib；
The spacing initial setting of S3, the spacing initial setting a for giving adjacent lengthways of rod and given adjacent transverse rib
B, while the thickness t of given covering, the skin thickness are the rib web thickness of the Material Stiffened Panel；
S4, the beginning buckling load that axis presses siding rib is calculated according to the sectional parameter in step S1 and a, b value in step S3；
S5, the breaking load that axis presses siding rib is calculated according to the sectional parameter in step S1, a, b value in step S3；
The ratio n of S6, the breaking load and the beginning buckling load of axis pressure siding rib for calculating axis pressure siding rib, and again
A, b and t value are set, step S3~S6 is repeated, until n meets preset value.
2. axis pressure Material Stiffened Panel post-buckling as described in claim 1 carries design method, it is characterised in that：The calculating axis pressure
The back of the breaking load of siding rib further includes the Euler's stress and axis pressure siding rib for calculating axis pressure siding rib
Siding crushing intensity, the breaking load σ of the axis pressure siding ribc0=[1- (1- σcr/σf)(σcr/σe)]σf, wherein the σe
Euler's stress of siding rib, σ are pressed for axisfThe siding crushing intensity of siding rib, σ are pressed for the axiscrSiding is pressed for the axis
The beginning buckling load of rib.
3. axis pressure Material Stiffened Panel post-buckling as claimed in claim 2 carries design method, it is characterised in that：The calculating axis pressure
The back of the beginning buckling load of siding rib includes calculating the siding crushing intensity for stating axis pressure siding rib.
4. axis pressure Material Stiffened Panel post-buckling as claimed in claim 3 carries design method, it is characterised in that：The calculating axis pressure
The Europe tensile stress sigma of siding ribe=C π2E/(L'/ρ)2, wherein C is that coefficient is supported in Material Stiffened Panel end, and L is rib spacing, i.e. phase
The spacing b of adjacent transverse direction rib,I and A is respectively the moment of inertia and area of Material Stiffened Panel section.
5. axis pressure Material Stiffened Panel post-buckling as claimed in claim 4 carries design method, it is characterised in that：The axis presses siding
The siding crushing intensity σ of ribf=σ0.2β[(fδt/F)(E/σ0.2)(1/2)]0.4, wherein β is to be determined according to cutting number and flange number
Fixed pressure loss coefficient, f cut the sum of number and flange number, δ skin thickness, and F is Material Stiffened Panel sectional area, σ0.2For the surrender of material
The limit, E are the elasticity modulus of material.
6. axis pressure Material Stiffened Panel post-buckling as claimed in claim 4 carries design method, it is characterised in that：The axis presses siding
The local buckling limit stress σ of ribcr=K π2Eδ2/[12(1-μ2)a2], wherein K is that coefficient is supported on the boundary of reinforcement covering.
7. axis pressure Material Stiffened Panel post-buckling as described in claim 1 carries design method, it is characterised in that：The preset value n
It is 1.5.
8. axis pressure Material Stiffened Panel post-buckling as described in claim 1 carries design method, it is characterised in that：Described a, b and t
Obtaining value method include keep a, b value motionless, with particular step size increase x increase t value, alternatively, keeping a, t value motionless, with particular step size x
Increase the value of b, alternatively, keeping b, t value motionless, increases the value of a with particular step size x.
9. axis pressure Material Stiffened Panel post-buckling as claimed in claim 8 carries design method, it is characterised in that：The value of the x is
0.2mm。
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| CN110887737B (en) * | 2019-12-24 | 2022-04-19 | 中国航空工业集团公司西安飞机设计研究所 | Method for determining pressure loss strength test of composite material reinforced wall plate |
| CN111159943B (en) * | 2019-12-25 | 2023-07-21 | 中国航空工业集团公司西安飞机设计研究所 | Buckling treatment method of movable airfoil surface sealing structure |
| CN111274670B (en) * | 2019-12-31 | 2023-08-08 | 中国航空工业集团公司沈阳飞机设计研究所 | Shaft pressure bearing capacity test design method for titanium alloy profile combined wallboard |
| CN111553030B (en) * | 2020-04-24 | 2023-05-23 | 中国飞机强度研究所 | Method for calculating damage load of integral reinforced wallboard |
| CN112763317B (en) * | 2020-12-29 | 2024-05-24 | 中国航空工业集团公司西安飞机设计研究所 | Method for measuring end support coefficient of axial compression clamp |
| CN113443169B (en) * | 2021-06-11 | 2022-08-02 | 航空工业第一飞机设计研究院 | Test method for actively controlling damage and fracture of integral wallboard structure |
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