CN105426691A - Method for calculating normal section ultimate bearing capacity of reinforced core beam by bar planting method - Google Patents

Abstract

The invention provides a method for calculating the normal section ultimate bearing capacity of a reinforced core beam by a bar planting method, belonging to the technical field of beam reinforcement. The calculation method comprises the following steps: (1) making a basic assumption on the reinforcing process; (2) calculating the stress-strain relation of the cross section of a core material under the condition that each material is damaged; (3) calculating the height of a pressure zone of the cross section of the core material under the condition that each material is damaged; (4) calculating the height of plastic development of the pressure zone of the cross section of the core material under the condition that each material is damaged; and (5) calculating the normal section bending capacity of the reinforced core beam according to the height of the pressure zone and the height of plastic development of the pressure zone of the cross section of the core material under the condition that each material is damaged, thus obtaining the normal section ultimate bearing capacity of the reinforced core beam in consideration with the plastic development. The calculation method can be used for effectively calculating the normal section ultimate bearing capacity of the reinforced core beam in consideration with the plastic development by the bar planting method, thus providing powerful theoretical guidance for engineering application.

Description

Bar planting method adds the computing method of the Ultimate flexural strength being installed with core beam

Technical field

The invention belongs to beam reinforcement technique field, relate to a kind of computing method of ultimate bearing capacity, especially add the computing method of the ultimate bearing capacity being installed with core beam.

Background technology

The Chinese ancient architecture overwhelming majority is under the jurisdiction of timber buildings, and these ancient buildings are owing to being exposed to the sun and rain for a long time, and termite moth erosion infringement, component surface corrosion and ageing, the security of building is reducing year by year.Current is all generally adopt to change whole beam to the reinforcement and repair of historic building fire prevention, or carries out grout filling to hole, crack.These methods improve the security of ancient building to a certain extent; Its weak point needs before being to change beam column to unload the beam column of building, and there is potential safety hazard, and speed of application is slow, cost is high.After changing in addition there is notable difference in the outward appearance of component and original part, run counter to the principle with antique value ancient building " restoring the old as the old ".

The corrosion of timber buildings central sill, a tree, used in making timber for boats component mainly occurs in two ends and the upper position of component, and near courtyard He Men, Lang Chu beam generally than the beam of building interior destroy even more serious, especially the Hui Style Architecture such as some ancestral halls, mansion government office in feudal China, temple, long neglected and in disrepair, the phenomenon such as cornice position is many can exist roof leaking, leak, cause beam outwardly sound, but the special damage-form of one when medulla part is rotted, and this phenomenon is also comparatively general.

For the method and technology that wood beam reinforcing is repaired, there are a large amount of theories and analysis of experiments both at home and abroad, but be all directly paste the reinforcing modes such as steel, cloth material and embedding rib on the surface of former beam substantially, what adopt is improve the reinforcement technique that the bearing capacity of destroyed test specimen or rigidity are main target, and the mode of consolidation process be unidirectional, irreversible, can not second consolidation, and to the appearance effects of wooden frame larger.The particularly important is; to see and can the reinforcement technique of second consolidation for architecture protection beyond the region of objective existence can be realized; how systematic research is carried out to its structural system design theory; currently do not form the theoretical foundation and analysis design method that instruct engineer applied yet, more do not have corresponding specification can be according to.Especially, when calculating the ultimate bearing capacity of reinforcement, usually only considering the ultimate bearing capacity of Flexible development, and not considering the ultimate bearing capacity of plasticity, the performance of reinforcement can not be reacted comparatively objectively, rational theoretical foundation can not be provided for engineer applied.

Summary of the invention

The object of the present invention is to provide and a kind ofly can realize architecture protection beyond the region of objective existence to see and can the method that calculates of the Ultimate flexural strength of beam reinforced of the reinforcement technique of second consolidation adopting.

In order to achieve the above object, solution of the present invention is:

Bar planting method adds computing method for the Ultimate flexural strength being installed with core beam, and wherein said muscle, as reinforcement material, implants the bottom of core to reinforce core, to reinforce described beam in the tensile region that described core is arranged on the shell of beam again; Said method comprising the steps of:

(1) basic assumption is done to reinforcing process;

(2) calculate described in add and be installed with in core beam under each material damage situation, the stress-strain relation of the xsect of described core;

(3) under calculating each material damage situation, the height of the plasticity of the compressive region of the height of the compressive region of the xsect of described core and the xsect of described core;

(4) according to the height of compressive region of the xsect of described core under each material damage situation and the height of the plasticity of compressive region, add the flexure bearing capacity being installed with core beam under calculating corresponding each material damage situation, obtain adding the Ultimate flexural strength of the consideration plasticity being installed with core beam.

Described muscle is CFRP muscle or reinforcing bar.

The basic assumption of described step (1) comprising:

(11) suppose that the shell of beam is zero to adding the contribution being installed with core beam;

(12) all plane is kept before and after the cross-sectional deformation supposing to put core beam;

(13), before supposing to put core beam tensile region cracking, there is not bond-slip phenomenon in compatible deformation between reinforcement material and core;

(14) suppose that the pressurized constitutive model of core gets ideal elastoplastic model, tension constitutive model line taking elastic model;

(15) when described muscle is CFRP muscle, the constitutive model line taking elastic model of CFRP muscle is supposed; When described muscle is reinforcing bar, suppose that the constitutive model of reinforcing bar selects ideal elastoplastic model.

Described core is timber, comprises xylogen; Described each material damage situation comprises:

The destruction caused broken by the xylogen of the core of tension;

The xylogen of the core of pressurized reaches capacity the destruction straining and cause;

When described muscle is CFRP muscle, CFRP muscle reaches capacity the destruction that intensity causes; When described muscle is reinforcing bar, the destruction of ftractureing and causing broken by the xylogen of reinforcement yielding, core.

Described step (2) comprising:

When the xylogen being calculated as follows the core of tension is broken and is caused destruction, the stress-strain relation of the xsect of core:

$\frac{{\mathrm{\ϵ}}_{tu}^w}{{\mathrm{\ϵ}}_{cy}^w}=\frac{h_0-x_c}{x_c-x_{cp}}=\frac{{\mathrm{\σ}}_{tu}^w}{{\mathrm{\σ}}_{cy}^w}=R_{\mathrm{\σ}}$

Wherein: represent the ultimate tensile strength of the xylogen of core;

represent the yield pressure strain of the xylogen of core;

H ₀represent the distance of stressed geometric center to the pressurized edge of core of muscle;

X _crepresent the height of the compressive region of the xsect of core;

X _cprepresent the height of the plastic zone development of the compressive region of the xsect of core;

represent the ultimate tensile stress of the xylogen of core when considering strength degradation;

represent the yield bearing stress of the xylogen of core when not considering strength degradation;

R _σrepresent the maximum tension stress of xylogen and the ratio of maximum crushing stress of core;

The xylogen being calculated as follows the core of pressurized reaches capacity compressive strain when causing destruction, the stress-strain relation of the xsect of core:

$\frac{x_{cp}}{x_c-x_{cp}}=\frac{{\mathrm{\ϵ}}_{cu}^w-{\mathrm{\ϵ}}_{cy}^w}{{\mathrm{\ϵ}}_{cy}^w}={\mathrm{\γ}}_{\mathrm{\ϵ}}$

Wherein: represent the compressive ultimate strain of the xylogen of core;

γ _εrepresent the ultimate plastic strain of xylogen and the ratio of elastic strain of core;

When described muscle is CFRP muscle, is calculated as follows CFRP muscle and reaches capacity intensity when causing destruction, the stress-strain relation of the xsect of core:

$\frac{{\mathrm{\ϵ}}_{tu}^F}{{\mathrm{\ϵ}}_{cy}^w}=\frac{{\mathrm{\σ}}_{tu}^F}{{\mathrm{\α}}_E{\mathrm{\σ}}_{cy}^w}=\frac{h_0-x_c}{x_c-x_{cp}}$

Wherein: represent the ultimate tensile strength in CFRP muscle constitutive model;

represent the ultimate tensile stress in CFRP muscle constitutive model;

α _erepresent the ratio of the elastic modulus of CFRP muscle and the elastic modulus of core;

When described muscle is reinforcing bar, is calculated as follows reinforcement yielding, the xylogen of core break cracking when causing destruction, the stress-strain relation of the xsect of core:

$\frac{{\mathrm{\ϵ}}_{tu}^w}{{\mathrm{\ϵ}}_{cy}^w}=\frac{{\mathrm{\σ}}_{tu}^w}{{\mathrm{\σ}}_{cy}^w}=\frac{h_0-x_c}{x_c-x_{cp}}.$

Under calculating each material damage situation in described step (3), the height of the compressive region of the xsect of described core comprises: when the xylogen calculating the core of tension is according to the following formula broken and caused destruction, the xylogen of the core of pressurized reaches capacity compressive strain when causing destruction, CFRP muscle when described muscle is CFRP muscle reaches capacity intensity when causing destruction, reinforcement yielding when described muscle is reinforcing bar, the xylogen of core break cracking when causing destruction, the height x of the compressive region of the xsect of core _c:

$\ΣF_i={\∫}_{-h/2}^{h/2}{\mathrm{\σ}}^w\left(x_c\right)b\left(x_c\right){\mathrm{dx}}_c+{\mathrm{\σ}}_t^F{A}^F=0$

Wherein: F _irepresent the internal force of each material or component;

H represents the height of the xsect of core;

σ ^w(x _c) represent the height x of compressive region of the xsect of core _cthe stress of place's xylogen;

B (x _c) represent the height x of compressive region of the xsect of core _cthe cross-sectional width at place;

represent the tension of tension reinforcement material;

A ^frepresent the area of tension reinforcement material.

Under calculating each material damage situation in described step (3), the height of the plasticity of the compressive region of the xsect of described core comprises: the stress-strain relation of the xsect of core under each material damage situation calculated in integrating step (2), the height x of the plasticity of the compressive region of the xsect of core under each material damage situation that calculating is corresponding _cp.

Described step (4) comprising:

The flexure bearing capacity being installed with core beam is added under being calculated as follows each material damage situation:

$M={\mathrm{\σ}}_{cy}^{w}b\left(x_{cp}\right(x_c-\frac{x_{cp}}{2})+\frac{{(x_c-x_{cp})}^3+{(h-x_c)}^3}{3(x_c-x_{cp})})+\frac{{\mathrm{\α}}_E{\mathrm{\σ}}_{cy}^w{A}^F{(h-x_c)}^2}{x_c-x_{cp}}$

Wherein: the flexure bearing capacity putting core beam after M represents reinforcing;

B represents the width of the xsect of core;

X _crespectively according to the x under destruction situation corresponding in step (3) _cexploitation;

X _cprespectively according to the x under destruction situation corresponding in step (3) _cpexploitation.

Described step (4) also comprises: add under tried to achieve each material damage situation and be installed with in the flexure bearing capacity of core beam, gets minimum value as the described Ultimate flexural strength adding the consideration plasticity being installed with core beam.

Owing to adopting such scheme; the invention has the beneficial effects as follows: the present invention proposes the computing method that a kind of bar planting method adds the Ultimate flexural strength being installed with core beam; add for adopting bar planting method the design being installed with core beam and provide theoretical direction; ensure that adopt reinforce in this way put core beam and can reach designing requirement; thus effectively architecture protection beyond the region of objective existence see intact, intensity reaches requirement and can second consolidation.

Accompanying drawing explanation

Fig. 1 a is the schematic diagram of the core after adopting bar planting mode to reinforce in the embodiment of the present invention;

Fig. 1 b is the schematic diagram of embodiment of the present invention Central Plains beam shell;

Fig. 1 c be obtain after reinforcing the former beam shell of Fig. 1 b with the core of Fig. 1 a add the schematic diagram being installed with core beam;

Fig. 2 is the curve map of the constitutive relation model of core in the embodiment of the present invention;

Fig. 3 is the curve map of the constitutive relation model of CFRP muscle in the embodiment of the present invention;

Fig. 4 is the curve map of the constitutive relation model of regular reinforcement in the embodiment of the present invention;

Fig. 5 a is one of calculating schematic diagram of the height of the compressive region of the xsect of core in the embodiment of the present invention;

Fig. 5 b is the calculating schematic diagram two of the height of the compressive region of the xsect of core in the embodiment of the present invention;

Fig. 6 a is one of schematic diagram of the flexure bearing capacity calculation of the mid-core wooden frame of the embodiment of the present invention;

Fig. 6 b is the schematic diagram two of the flexure bearing capacity calculation of the mid-core wooden frame of the embodiment of the present invention;

Fig. 6 c is the schematic diagram three of the flexure bearing capacity calculation of the mid-core wooden frame of the embodiment of the present invention.

In accompanying drawing: 1, muscle; 2, core; 3, former beam shell.

Embodiment

Below in conjunction with accompanying drawing illustrated embodiment, the present invention is further illustrated.

For lacking in prior art ancient building outward appearance can be protected and the technology of second consolidation beam can carry out the technology of theoretical research, the present invention proposes the computing method that a kind of bar planting method adds the Ultimate flexural strength being installed with core beam.This bar planting method adds in the technology being installed with core beam, and adopt muscle 1 as reinforcement material, reinforce core 2, the core 2 after reinforcing is inserted in the tensile region of former beam shell 3.Wherein, bar planting method is adopted to be that bottom muscle 1 being inserted core 2 reinforces core 2 to the process that core is reinforced.Fig. 1 a is the schematic diagram of the core after adopting CFRP (carbon fibre reinforced composite) plate to reinforce; Fig. 1 b is the schematic diagram of former beam shell, and wherein area of absence is its tensile region; Fig. 1 c be obtain after reinforcing the former beam shell of Fig. 1 b with the reinforcing core of Fig. 1 a add the schematic diagram being installed with core beam.In the present embodiment, core 2 is timber, comprises xylogen.

The computing method that the bar planting method that the present invention proposes adds the Ultimate flexural strength being installed with core beam comprise the following steps:

The first step, following basic assumption is done to this reinforcing process:

1) supposing not consider that former beam shell is to adding the contribution being installed with core beam, namely supposing that former beam is zero to adding the contribution being installed with core beam;

2) suppose to add before and after the cross-sectional deformation being installed with core beam and all keep plane, namely meet plane cross-section assumption;

3) suppose to add be installed with core beam tensile region cracking before, there is not bond-slip phenomenon in compatible deformation between reinforcement material (i.e. muscle) and core;

4) suppose that core pressurized constitutive model gets ideal elastoplastic model, tension constitutive model line taking elastic model, as shown in Figure 2.Wherein, the pressure-proof elasticity modulus of core with tensile modulus of elasticity get identical numerical value, get wherein, the compressive ultimate strain of the xylogen of core, the yield pressure strain of the xylogen of core, it is the ultimate tensile strength of the xylogen of core.In Fig. 2, ε ^wrepresent the strain of the xylogen of core; σ ^wrepresent the stress of the xylogen of core; represent the limit compressive stress of the xylogen of core; represent the ultimate tensile stress of the xylogen of core.

5) when muscle is CFRP muscle, suppose that CFRP muscle only considers the intensity of the direction of wooden fibers along core, stress equals to strain the product with its elastic modulus, but its absolute value is not more than its corresponding strength failure criterion, constitutive model chooses linear elastic model, as shown in Figure 3.Wherein, represent the ultimate tensile strength of CFRP muscle; represent the ultimate tensile stress of CFRP muscle; represent the tensile modulus of elasticity of CFRP muscle; σ ^frepresent the stress of CFRP muscle; ε ^frepresent the strain of CFRP muscle.

When muscle is regular reinforcement, suppose that the stress of regular reinforcement equals the product of its strain and its elastic module, but its absolute value is not more than the strength failure criterion of its respective design, ultimate tensile strength get 0.01, constitutive model selects ideal elastoplastic model, as shown in Figure 4.In Fig. 4, σ ^srepresent the stress of regular reinforcement; represent the surrender stretching strain of regular reinforcement; represent the yield bearing stress of regular reinforcement; represent the yield pressure strain of regular reinforcement; represent the surrender tension of regular reinforcement; ε ^srepresent the strain of regular reinforcement; represent the tensile modulus of elasticity of regular reinforcement.

Second step, according to plane cross-section assumption, calculates the stress-strain relation of putting the xsect of core under each material damage situation of core beam after reinforcing, comprising:

When the xylogen being calculated as follows the core of tension is broken and is caused destruction, the stress-strain relation of the xsect of core:

$\frac{{\mathrm{\ϵ}}_{tu}^w}{{\mathrm{\ϵ}}_{cy}^w}=\frac{h_0-x_c}{x_c-x_{cp}}=\frac{{\mathrm{\σ}}_{tu}^w}{{\mathrm{\σ}}_{cy}^w}=R_{\mathrm{\σ}}$

Wherein: represent the ultimate tensile strength of the xylogen of core;

represent the yield pressure strain of the xylogen of core;

H ₀represent the distance of stressed geometric center to the pressurized edge of core of muscle;

X _crepresent the height of the compressive region of the xsect of core;

X _cprepresent the plasticity height of the compressive region of the xsect of core;

to represent when considering strength degradation the ultimate tensile stress of the xylogen of (when namely considering the reduction of the defects such as core tensile region knaur, hole and desciccation crack to tensile strength) core;

to represent when not considering strength degradation the yield bearing stress of the xylogen of (when namely not considering the reduction of the defects such as core tensile region knaur, hole and desciccation crack to tensile strength) core;

R _σrepresent the maximum tension stress of xylogen and the ratio of maximum crushing stress of core.

The xylogen being calculated as follows the core of pressurized reaches capacity compressive strain when causing destruction, the stress-strain relation of the xsect of core:

$\frac{x_{cp}}{x_c-x_{cp}}=\frac{{\mathrm{\ϵ}}_{cu}^w-{\mathrm{\ϵ}}_{cy}^w}{{\mathrm{\ϵ}}_{cy}^w}={\mathrm{\γ}}_{\mathrm{\ϵ}}$

Wherein: represent the compressive ultimate strain of the xylogen of core;

γ _εrepresent the ultimate plastic strain of xylogen and the ratio of elastic strain of core.

When muscle is CFRP muscle, is calculated as follows CFRP muscle and reaches capacity intensity when causing destruction, the stress-strain relation of the xsect of core:

$\frac{{\mathrm{\ϵ}}_{tu}^F}{{\mathrm{\ϵ}}_{cy}^w}=\frac{{\mathrm{\σ}}_{tu}^F}{{\mathrm{\α}}_E{\mathrm{\σ}}_{cy}^w}=\frac{h_0-x_c}{x_c-x_{cp}}$

Wherein: represent the ultimate tensile strength in CFRP plate constitutive model;

represent the ultimate tension in CFRP plate constitutive model;

α _erepresent the ratio of the elastic modulus of CFRP plate and the elastic modulus of core.

When muscle is regular reinforcement, is calculated as follows regular reinforcement bar planting material yield, the xylogen of core break cracking when causing destruction, the stress-strain relation of the xsect of core:

$\frac{{\mathrm{\ϵ}}_{tu}^w}{{\mathrm{\ϵ}}_{cy}^w}=\frac{{\mathrm{\σ}}_{tu}^w}{{\mathrm{\σ}}_{cy}^w}=\frac{h_0-x_c}{x_c-x_{cp}}$

3rd step, according to various in second step and cross section static balance condition, when calculating each material damage according to the following formula, namely when the xylogen of the core of tension is broken and is caused destruction, the xylogen of the core of pressurized reach capacity the CFRP muscle of compressive strain when causing destruction, when muscle is CFRP muscle reach capacity the regular reinforcement surrender of intensity when causing destruction, when muscle is regular reinforcement, core xylogen break cracking when causing destruction, the height x of the compressive region of the xsect of core _c, as shown in figure 5 a and 5b:

$\ΣF_i={\∫}_{-h/2}^{h/2}{\mathrm{\σ}}^w\left(x_c\right)b\left(x_c\right){\mathrm{dx}}_c+{\mathrm{\σ}}_t^F{A}^F=0$

Wherein: F _irepresent the internal force of each material or component;

H represents the height of the xsect of core;

σ ^w(x _c) represent the height x of xsect of core _cthe stress of place's xylogen;

B (x _c) represent the height x of xsect of core _cthe width in the cross section at place;

represent the tension of tension reinforcement material;

A ^frepresent the area of tension reinforcement material.

In Fig. 5 b, represent the compressive strain of the xylogen of core; represent the tensile strain of the xylogen of core; represent the tensile strain of tension reinforcement material.

4th step, in conjunction with the stress-strain relation of the xsect of core under each material damage situation calculated in second step, the height x of the plasticity of the compressive region of the xsect of core under each material damage situation that calculating is corresponding _cp.

5th step, as shown in Fig. 6 a, Fig. 6 b and Fig. 6 c, calculates the flexure bearing capacity putting core beam after reinforcing according to the following formula:

$M={\mathrm{\σ}}_{cy}^{w}b\left(x_{cp}\right(x_c-\frac{x_{cp}}{2})+\frac{{(x_c-x_{cp})}^3+{(h-x_c)}^3}{3(x_c-x_{cp})})+\frac{{\mathrm{\α}}_E{\mathrm{\σ}}_{cy}^w{A}^F{(h-x_c)}^2}{x_c-x_{cp}}$

Wherein: the flexure bearing capacity putting core beam after M represents reinforcing;

B represents the width of the xsect of core;

X _crespectively according to the x under destruction situation corresponding in the 3rd step _cexploitation;

X _cprespectively according to the x under destruction situation corresponding in the 4th step _cpexploitation.

Add under tried to achieve each material damage situation and be installed with in the flexure bearing capacity of core beam, get minimum value as the Ultimate flexural strength adding the consideration plasticity being installed with core beam.

In Fig. 6 a, a represents the distance of the stressed geometric center of muscle to the tension edge of core.F ^frepresent making a concerted effort of reinforcement material (regular reinforcement or CFRP muscle); represent the tension stress of the xylogen of core.

The Ultimate flexural strength putting core wooden frame obtained according to the method described above, can as the guidance of correlation theory research and engineer applied, auxiliaryly obtains reaching adding of designing requirement and is installed with core wooden frame.

Usually, the core wooden frame of putting that the bar planting method of complete design is reinforced meets following functional requirement the design life planted agent of regulation:

(1) the various effects that may occur can be born when normal construction and normal use;

(2) the indices control overflow of structure can be met when normal construction and normal use;

(3) when normal use, there is good serviceability;

(4) under conventional maintenance, there is enough endurance qualities;

(5) when the incident of design code occurs and after occurring, still required resistance to overturning can be kept.

The above-mentioned requirement of putting core wood structure member function of reinforcing bar planting method is in fact to have enough intensity, can bear the internal force that least favorable load effect produces, meet ultimate limit states requirement.In addition, economy and the operability of considering design proposal is also needed.

The design Main Basis following steps of putting core wood structure component that bar planting method is reinforced are carried out, and economy, reasonable, a feasible design proposal often need repeatedly to revise to calculate through several times just can obtain:

(1) second inner force of structure is determined;

(2) according to requirements and the overall plan worked out and version, with reference to existing design and related data, the sectional dimension of putting core wooden frame sectional dimension and bar planting material of taking to reinforce and length is tentatively determined;

(3) adopt model for internal force analysis, calculate the maximum effect of combination of load effect and controlling sections;

(4) according to the design internal force of controlling sections under ultimate limit states and serviceability limit state and the sectional dimension tentatively worked out, estimate the type of bar planting material, quantity, size and arrangement, and carry out reasonable Arrangement.If bar planting material cannot reasonable Arrangement, then should return (2) step, amendment sectional dimension;

(5) section stress of construction stage, transport and installation phase and operational phase is checked;

(6) anchorage length is checked.

In sum; the present invention proposes the computing method that a kind of bar planting method adds the Ultimate flexural strength being installed with core beam; add for adopting bar planting method the design being installed with core beam and provide theoretical direction; ensure that adopt reinforce in this way put core beam and can reach designing requirement; thus effectively architecture protection beyond the region of objective existence see intact, intensity reaches requirement and can second consolidation.

Above-mentioned is can understand and apply the invention for ease of those skilled in the art to the description of embodiment.Person skilled in the art obviously easily can make various amendment to these embodiments, and General Principle described herein is applied in other embodiments and need not through performing creative labour.Therefore, the invention is not restricted to embodiment here, those skilled in the art, according to announcement of the present invention, do not depart from improvement that scope makes and amendment all should within protection scope of the present invention.

Claims (9)

1. a bar planting method adds the computing method of the Ultimate flexural strength being installed with core beam, wherein said muscle is as reinforcement material, implant the bottom of core to reinforce core, to reinforce described beam in the tensile region that described core is arranged on the shell of beam again, it is characterized in that: said method comprising the steps of:

(1) basic assumption is done to reinforcing process;

(2) calculate described in add and be installed with in core beam under each material damage situation, the stress-strain relation of the xsect of described core;

(3) under calculating each material damage situation, the height of the plasticity of the compressive region of the height of the compressive region of the xsect of described core and the xsect of described core;

(4) according to the height of compressive region of the xsect of described core under each material damage situation and the height of the plasticity of compressive region, add the flexure bearing capacity being installed with core beam under calculating corresponding each material damage situation, obtain adding the Ultimate flexural strength of the consideration plasticity being installed with core beam.

2. bar planting method according to claim 1 adds the computing method of the Ultimate flexural strength being installed with core beam, it is characterized in that: described muscle is CFRP muscle or reinforcing bar.

3. bar planting method according to claim 2 adds the computing method of the Ultimate flexural strength being installed with core beam, it is characterized in that: the basic assumption of described step (1) comprising:

(11) suppose that the shell of beam is zero to adding the contribution being installed with core beam;

(12) all plane is kept before and after the cross-sectional deformation supposing to put core beam;

(13), before supposing to put core beam tensile region cracking, there is not bond-slip phenomenon in compatible deformation between reinforcement material and core;

(14) suppose that the pressurized constitutive model of core gets ideal elastoplastic model, tension constitutive model line taking elastic model;

(15) when described muscle is CFRP muscle, the constitutive model line taking elastic model of CFRP muscle is supposed; When described muscle is reinforcing bar, suppose that the constitutive model of reinforcing bar selects ideal elastoplastic model.

4. bar planting method according to claim 2 adds the computing method of the Ultimate flexural strength being installed with core beam, it is characterized in that: described core is timber, comprises xylogen; Described each material damage situation comprises:

The destruction caused broken by the xylogen of the core of tension;

The xylogen of the core of pressurized reaches capacity the destruction straining and cause;

When described muscle is CFRP muscle, CFRP muscle reaches capacity the destruction that intensity causes; When described muscle is reinforcing bar, the destruction of ftractureing and causing broken by the xylogen of reinforcement yielding, core.

5. bar planting method according to claim 3 adds the computing method of the Ultimate flexural strength being installed with core beam, it is characterized in that: described step (2) comprising:

When the xylogen being calculated as follows the core of tension is broken and is caused destruction, the stress-strain relation of the xsect of core:

$\frac{{\mathrm{\ϵ}}_{tu}^w}{{\mathrm{\ϵ}}_{cy}^w}=\frac{h_0-x_c}{x_c-x_{cp}}=\frac{{\mathrm{\σ}}_{tu}^w}{{\mathrm{\σ}}_{cy}^w}=R_{\mathrm{\σ}}$

Wherein: represent the ultimate tensile strength of the xylogen of core;

represent the yield pressure strain of the xylogen of core;

H ₀represent the distance of stressed geometric center to the pressurized edge of core of muscle;

X _crepresent the height of the compressive region of the xsect of core;

X _cprepresent the height of the plastic zone development of the compressive region of the xsect of core;

represent the ultimate tensile stress of the xylogen of core when considering strength degradation;

represent the yield bearing stress of the xylogen of core when not considering strength degradation;

R _σrepresent the maximum tension stress of xylogen and the ratio of maximum crushing stress of core;

The xylogen being calculated as follows the core of pressurized reaches capacity compressive strain when causing destruction, the stress-strain relation of the xsect of core:

$\frac{x_{cp}}{x_c-x_{cp}}=\frac{{\mathrm{\ϵ}}_{cu}^w-{\mathrm{\ϵ}}_{cy}^w}{{\mathrm{\ϵ}}_{cy}^w}={\mathrm{\γ}}_{\mathrm{\ϵ}}$

Wherein: represent the compressive ultimate strain of the xylogen of core;

γ _εrepresent the ultimate plastic strain of xylogen and the ratio of elastic strain of core;

When described muscle is CFRP muscle, is calculated as follows CFRP muscle and reaches capacity intensity when causing destruction, the stress-strain relation of the xsect of core:

Wherein: represent the ultimate tensile strength in CFRP muscle constitutive model;

represent the ultimate tensile stress in CFRP muscle constitutive model;

α _erepresent the ratio of the elastic modulus of CFRP muscle and the elastic modulus of core;

When described muscle is reinforcing bar, is calculated as follows reinforcement yielding, the xylogen of core break cracking when causing destruction, the stress-strain relation of the xsect of core:

6. bar planting method according to claim 5 adds the computing method of the Ultimate flexural strength being installed with core beam, it is characterized in that: under calculating each material damage situation in described step (3), the height of the compressive region of the xsect of described core comprises: when the xylogen calculating the core of tension is according to the following formula broken and caused destruction, the xylogen of the core of pressurized reaches capacity compressive strain when causing destruction, CFRP muscle when described muscle is CFRP muscle reaches capacity intensity when causing destruction, reinforcement yielding when described muscle is reinforcing bar, the xylogen of core breaks cracking when causing destruction, the height x of the compressive region of the xsect of core _c:

${\mathrm{\ΣF}}_i={\∫}_{-h/2}^{h/2}{\mathrm{\σ}}^w\left(x_c\right)b\left(x_c\right){\mathrm{dx}}_c+{\mathrm{\σ}}_t^F{A}^F=0$

Wherein: F _irepresent the internal force of each material or component;

H represents the height of the xsect of core;

σ ^w(x _c) represent the height x of compressive region of the xsect of core _cthe stress of place's xylogen;

B (x _c) represent the height x of compressive region of the xsect of core _cthe cross-sectional width at place;

represent the tension of tension reinforcement material;

A ^frepresent the area of tension reinforcement material.

7. bar planting method according to claim 5 adds the computing method of the Ultimate flexural strength being installed with core beam, it is characterized in that: under calculating each material damage situation in described step (3), the height of the plasticity of the compressive region of the xsect of described core comprises: the stress-strain relation of the xsect of core under each material damage situation calculated in integrating step (2), the height x of the plasticity of the compressive region of the xsect of core under each material damage situation that calculating is corresponding _cp.

8. bar planting method according to claim 7 adds the computing method of the Ultimate flexural strength being installed with core beam, it is characterized in that: described step (4) comprising:

The flexure bearing capacity being installed with core beam is added under being calculated as follows each material damage situation:

$M={\mathrm{\σ}}_{cy}^{w}b\left(x_{cp}\right(x_c-\frac{x_{cp}}{2})+\frac{{(x_c-x_{cp})}^3+{(h-x_c)}^3}{3(x_c-x_{cp})})+\frac{{\mathrm{\α}}_E{\mathrm{\σ}}_{cy}^w{A}^F{(h-x_c)}^2}{x_c-x_{cp}}$

Wherein: the flexure bearing capacity putting core beam after M represents reinforcing;

B represents the width of the xsect of core;

X _crespectively according to the x under destruction situation corresponding in step (3) _cexploitation;

X _cprespectively according to the x under destruction situation corresponding in step (3) _cpexploitation.

9. bar planting method according to claim 8 adds the computing method of the Ultimate flexural strength being installed with core beam, it is characterized in that: described step (4) also comprises: add under tried to achieve each material damage situation and be installed with in the flexure bearing capacity of core beam, get minimum value as the described Ultimate flexural strength adding the consideration plasticity being installed with core beam.