CN101881089A - Evaluation method of earthquake resistant performance of steel tube concrete building and application - Google Patents

Abstract

The invention relates to an evaluation method of earthquake resistant performance of a steel tube concrete building. A building support component is formed by steel tube concrete. The evaluation method comprises the following steps of establishing a space fiber beam finite element model of the steel tube concrete building, developing an analysis method suitable for a fiber beam, considering that the confinement effect and the material characteristic of the elasto-plasticity under earthquake cyclic loading damage a constitutive model and a corresponding subprogram, calculating the finite element model by adopting a software and combining with the material subprogram, evaluating the earthquake resistant performance, and designing the earthquake resistant measure of the building. In the provided evaluation method of the earthquake resistant performance of the steel tube concrete building, the earthquake resistant performance of the building is evaluated on the basis of the maximum inter-story displacement angle limit value required by a steel tube concrete structure by establishing the space fiber beam finite element model of the steel tube concrete building, developing the analysis method suitable for the fiber beam, considering that the confinement effect and the material characteristic of the elasto-plasticity under earthquake cyclic loading damage the constitutive model, calculating the finite element model by adopting the software and obtaining the maximum inter-story displacement angle of the building, and building earthquake resistant measures are planed according to the evaluation result of the earthquake resistant performance of the building.

Description

Evaluation method of earthquake resistant performance of steel tube concrete building and application

Technical field

The present invention relates to a kind of Antiseismic building performance estimating method and application, relate in particular to a kind of evaluation method of earthquake resistant performance of steel tube concrete building and application.

Background technology

Building aseismicity designing requirement " little shake is not bad; middle shake can be repaiied; no collapsing with strong earthquake " at present, at concrete structure design, requiring the seismic Calculation of high-rise building mainly is under the frequently occurred earthquake effect, press reacting spectrum theory and calculate geological process, with elastic method calculating internal force and displacement, and with ultimate limit state method designed component; For important building or when specific (special) requirements is arranged, use the direct driving force method---the time-history analysis method is replenished and is calculated, and the deformation analysis under the effect of shaking greatly.

Calculate and to be divided into over against structural seismic: static(al) method and dynamic method.Wherein, the static(al) method mainly is based on reacting spectrum theory and the equivalent analysis method set up, as at the modal analysis method of frequently occurred earthquake flexibility analysis, at Static Elasto-Plastic Analysis method of big shake etc.Dynamic method then directly puts on geological process on the structure, adopts progressively the method for integration to find the solution transient state internal force and the distortion situation of structure under geological process, as elasticity and elastoplasticity Dynamic time history analysis method etc.Wherein, elastoplasticity Dynamic time history analysis method can obtain structure from elasticity to the elastoplasticity, and ftracture gradually, damage until the overall process of collapsing, thus can be by the condition of control destructiveness, and then seek the measure prevent structural collapse, be The common calculation methods comparatively at present.

Elastoplasticity Dynamic time history analysis method is by after seismic wave was quantized by the period, the oscillatory differential equation of input structure system, adopt step by step integration to carry out the analysis of structure dynamic elastoplastic response, calculate the vibrational state overall process of structure in whole earthquake time domain, provide each internal force and distortion of each rod member constantly, and the influence of direction, characteristic and the continuous action of reflection ground motion the order of plastic hinge appears, in each rod member.It checks the safety and the Aseismic Reliability of structure from intensity and two aspects of distortion, and distinguishes structure surrender mechanism and type.

At present, steel tube concrete building is more and more widely used, and is mainly used in transmission of electricity, in power transformation tower engineering and some high levels and the high-rise structure.Do not carry out high-rise elastoplasticity anti-seismic performance assessment but be applied to time-history analysis for steel tube concrete building, it is not enough to cause anti-seismic performance to be analyzed.

At high-rise concrete filled steel tube elastoplasticity seismic Calculation, in order to show the different qualities of steel pipe and concrete material really, and their cuff effect, the general solid element that adopts when modeling analysis, because number of components is a lot of during global analysis, the material model complexity, load has dynamic effect simultaneously, cause computing time very long, final being difficult to realized.If employing beam element, in general procedure, can only can use beam element, and concrete filled steel tube is made up of two kinds of materials at homogenous material, inapplicable, and do not have to be applicable to this structure of concrete fiber of space beam element kinematic analysis in a lot of softwares, finally also can't effectively analyze.

Summary of the invention

The technical problem that the present invention solves is: overcome and do not adopt elastoplasticity Dynamic time history analysis method that steel tube concrete building is carried out the anti-seismic performance analysis in the prior art in steel tube concrete building, the technical problem of anti-seismic performance analytical effect difference.

Technical scheme of the present invention is: a kind of evaluation method of earthquake resistant performance of steel tube concrete building is provided, and described building supporting member is formed by concrete filled steel tube, comprises the steps:

Set up the space fiber beam FEM (finite element) model of steel tube concrete building: the steel pipe and the concrete of concrete filled steel tube part in the building are all adopted the beam element modeling, physical dimension according to concrete filled steel tube is provided with steel pipe and concrete cross section, assemble steel pipe and concrete unit locus according to building in FEM (finite element) model, introduce and give the material structure model and the concrete material structure model of steel pipe in the building model, described constitutive model adopts the fiber elastoplastic Damage model of considering material behavior under cuff effect and the earthquake cyclic loading, be provided with that steel and concrete lotus root close condition in each concrete filled steel tubular member, by on finite element software, developing introducing.

Adopt software that described FEM (finite element) model is calculated: to set the fringe conditions of building model structure and apply geological process and carry out power Elastic time-history analysis and elasto-plastic time history analysis, thereby obtain the maximum relative storey displacement angle of building under seismic stimulation.

Anti-seismic performance assessment:, require the anti-seismic performance of assessment building according to the maximum relative storey displacement angle limit value that in " seismic design provision in building code " encased structures is required by the maximum relative storey displacement of the building angle value of obtaining.

The seismic measures of design building thing: according to the seismic measures of the assessment result design building thing of Antiseismic building performance.

Further technical scheme of the present invention is: in setting up the FEM (finite element) model step of steel tube concrete building, when adopting the beam element modeling, beam column is reduced to beam element, floor etc. is reduced to shell unit, the method of employing fiber beam is reduced to solid material the fibrous material of one dimension, and the influence of consideration cuff effect, consider damage and the fracture behaviour of material under reciprocating simultaneously, develop introducing by software.

Further technical scheme of the present invention is: in setting up the FEM (finite element) model step of steel tube concrete building, steel pipe and the direct constraints of concrete unit are coupling fully in the definition building model.

Further technical scheme of the present invention is: adopting software that described FEM (finite element) model is carried out in the calculation procedure, also comprising building model is divided grid, setting resistance coefficient and computing time.

Further technical scheme of the present invention is: adopting software that described FEM (finite element) model is carried out in the calculation procedure, the described method that applies geological process comprises load application and seismic wave.

Further technical scheme of the present invention is: adopting software that described FEM (finite element) model is carried out in the calculation procedure, described load application comprises compressive load and gravity load.

Further technical scheme of the present invention is: in setting up the FEM (finite element) model step of steel tube concrete building, also be included in building steel core concrete column and the beam connecting node place device unit that connects, local coordinate be set at the node place make connector unit meet the real work situation of steel tube concrete building.

Further technical scheme of the present invention is: in setting up the FEM (finite element) model step of steel tube concrete building, the value of node rigidity is less than 25 times beam line rigidity.

Technical scheme of the present invention is: evaluation method of earthquake resistant performance of steel tube concrete building is applied on the civilian construction or industrial construction that adopt steel tube concrete building.

Technique effect of the present invention is: the invention provides a kind of evaluation method of earthquake resistant performance of steel tube concrete building, by setting up the space fiber beam elastoplastic finite meta-model of steel tube concrete building, adopt software that described FEM (finite element) model is calculated then, by the maximum relative storey displacement of the building angle that obtains, the maximum relative storey displacement angle limit value that encased structures is required requires the anti-seismic performance of assessment building, according to the seismic measures of the assessment result design building thing of Antiseismic building performance.

Description of drawings

Fig. 1 is a flow chart of the present invention.

Fig. 2 is a steel single shaft hysteresis constitutive model of the present invention.

Fig. 3 is the confined concrete constitutive model of consideration lock ring of the present invention effect.

The specific embodiment

Below in conjunction with specific embodiment, technical solution of the present invention is further specified.

As shown in Figure 1, the specific embodiment of the present invention: a kind of evaluation method of earthquake resistant performance of steel tube concrete building is provided, and described building supporting member is formed by concrete filled steel tube, comprises the steps:

Step 100: the space fiber beam FEM (finite element) model of setting up steel tube concrete building: at first, the steel pipe and the concrete of concrete filled steel tube part in the building are all adopted the beam element modeling, promptly set up leverage and shell model, and leverage and shell model are that beam column is reduced to beam element, and floor etc. is reduced to shell unit.Then, physical dimension according to concrete filled steel tube is provided with steel pipe and concrete cross section, assemble steel pipe and concrete unit locus according to building in FEM (finite element) model, introduce and give the constitutive model and the concrete constitutive model of steel pipe in the building model, described constitutive model adopts the fiber elastoplastic Damage model of considering material behavior under cuff effect and the earthquake cyclic loading, be provided with that steel and concrete lotus root close condition in each concrete filled steel tubular member, by on finite element software, developing introducing.

Particularly, as shown in Figure 2, in the constitutive model of steel of the present invention, get steel single shaft hysteresis constitutive model and set up steel constitutive relation in the concrete filled steel tube.The steel model of exploitation is the Menegotto-Pinto boundary surface model, can consider steel etc. to reinforcement, can consider the Bauschinger effect in the hysteresis loading procedure simultaneously.

Among Fig. 2, in this model, tension is for just, and pressurized needs the parameter of definition to have 10: yield strength f for negative _yThe initial elasticity model E ₀Strengthen factor of proportionality b=E _t/ E ₀Initial elastoplasticity transforms controlling parameter R ₀, value does not have special demands to get 20 usually generally greater than 15; Elastoplasticity transforms the coefficient a in the controlling parameter design formulas ₁And a ₂, do not have the common a of special demands ₁=0.925, a ₂=0.15; Pressurized is strengthened design factor A ₁, A ₂If do not consider to strengthen, usually A ₁=0, A ₂=1; Tension is strengthened design factor A ₃, A ₄If do not consider to strengthen, usually A ₃=0, A ₃=1.

By the strain-stress relation in the hysteresis process of Fig. 2 as can be known, in the process of positive and negative loading, the relation of stress-strain is mainly by two point control, the i time starting point strain stress R _i(ε _r, σ _r) and turning point strain stress O _i(ε ₀, σ ₀), i is the number of times of mold cycle, during i=1, and R ₁(ε _r, σ _r) be the initial point of figure, O ₁(ε ₀, σ ₀) in σ ₀=f _y, wherein, f _yThe expression yield strength.The curvilinear equation of tension curve correspondence is as follows:

${\mathrm{\σ}}^{*}=b{\mathrm{\ϵ}}^{*}+\frac{(1-b){\mathrm{\ϵ}}^{*}}{{(1+{\mathrm{\ϵ}}^{*R})}^{1/R}}---\left(1\right)$

Wherein, ${\mathrm{\σ}}^{*}=\frac{\mathrm{\σ}-{\mathrm{\σ}}_r}{{\mathrm{\σ}}_0-{\mathrm{\σ}}_r};$ ${\mathrm{\ϵ}}^{*}=\frac{\mathrm{\ϵ}-{\mathrm{\ϵ}}_r}{{\mathrm{\ϵ}}_0-{\mathrm{\ϵ}}_r};$ $R=R_0-\frac{a_1\mathrm{\ξ}\left(i\right)}{a_2+\mathrm{\ξ}\left(i\right)}.$

Wherein, ε represents strain, and σ represents stress, R _i(ε _r, σ _r) the i time starting point strain stress: a of expression ₁, a ₂For elastoplasticity transforms controlling parameter, there is not the common a of special demands ₁=0.925, a ₂=0.15; B=E _t/ E ₀, b represents to strengthen factor of proportionality.

ξ (i) is the horizontal range of i curve break and historical maximum pressurized (or tension) point, turns to when drawing when curve has to press, and is the maximum tension point of history, when the curve tension turns to pressurized, is the maximum pressure spot of history; The corresponding yield point of initial maximum pressure spot and tension point position, and ξ (1)=0.

Strengthen criterion:

Pressurizeds etc. are when strengthening, and pressurized yield strength correction factor is k _c,

Pressurized yield strength after then strengthening is: f ' _Yc=k _cf _y

Tensions etc. are when strengthening, and tension yield stress correction factor is k _t,

Tensile yield strength after then strengthening is: f ' _Yt=k _tf _y

Wherein, ε _Max, ε _MinBe respectively historical maximum strain and minimum strain, f ' _Yc, f ' _YtBe respectively pressurized yield strength and tensile yield strength after the reinforcement.

Consider the confined concrete constitutive model of lock ring effect:

As shown in Figure 3, adopt modified Kent-Park model model for the CONCRETE CONSTITUTIVE RELATIONSHIP in the concrete-filled steel tubular hollow.In this model, tension is for just, and pressurized needs the parameter of definition to have 7: pressurized peak stress strain coordinate: (ε for negative _Cc, f _Cc), pressurized crushing place ess-strain coordinate: (ε _Cu, f _Cu), the loss coefficient of crushing place elastic analogy: α.The tension limit: f _t, tension softening stress-displacement stage modulus: E _t

Consider the formula description of the confined concrete constitutive model of lock ring effect:

If the initial pressurized modulus of elasticity of material The tension peak strain

The tension limiting strain is ${\mathrm{\ϵ}}_{\mathrm{ut}}=\frac{f_t}{E_t}+\frac{f_t}{E_0}.$

The confined concrete constitutive model envelope curve formula of considering the lock ring effect is:

During tension: $\left\{\begin{array}{cc}\mathrm{\ϵ}\≥{\mathrm{\ϵ}}_{\mathrm{ut}},& \mathrm{\σ}=0.0\\ {\mathrm{\ϵ}}_t\≤\mathrm{\ϵ}\≤{\mathrm{\ϵ}}_{\mathrm{ut}},& \mathrm{\σ}=-E_t(\mathrm{\ϵ}-{\mathrm{\ϵ}}_{\mathrm{ut}})\\ 0\≤\mathrm{\ϵ}\≤{\mathrm{\ϵ}}_t,& \mathrm{\σ}=E_0\mathrm{\ϵ}\end{array}\right.---\left(2\right)$

During pressurized, $\left\{\begin{array}{cc}{\mathrm{\ϵ}}_{\mathrm{cc}}\≤\mathrm{\ϵ}\≤0,& \mathrm{\σ}=f_{\mathrm{cc}}[2\left(\frac{\mathrm{\ϵ}}{{\mathrm{\ϵ}}_{\mathrm{cc}}}\right)-{\left(\frac{\mathrm{\ϵ}}{{\mathrm{\ϵ}}_{\mathrm{cc}}}\right)}^2]\\ {\mathrm{\ϵ}}_{\mathrm{cu}}\≤\mathrm{\ϵ}\≤{\mathrm{\ϵ}}_{\mathrm{cc}},& \mathrm{\σ}=\frac{f_{\mathrm{cc}}-f_{\mathrm{cu}}}{{\mathrm{\ϵ}}_{\mathrm{cc}}-{\mathrm{\ϵ}}_{\mathrm{cu}}}(\mathrm{\ϵ}-{\mathrm{\ϵ}}_{\mathrm{cc}})+f_{\mathrm{cc}}\\ \mathrm{\ϵ}\≥{\mathrm{\ϵ}}_{\mathrm{cu}},& \mathrm{\σ}=f_{\mathrm{cu}}\end{array}\right.---\left(3\right)$

As shown in Figure 3, hysteresis process rule: the tensile region is that linearity is got back to initial point;

Pressure zone: loading curve 3 was some R once more, and slope is the straight line of E, and wherein, some P was that the initial point slope is E ₀Straight line is α E with crossing a crushing point slope ₀The intersection point of straight line.Slope E is according to point (σ on the envelope _c, ε _c) and the R point come to determine.Unloading curve 1 was point (σ _c, ε _c) slope is E ₀Straight line, curve 2 be curve 1 and * the axle intersection point, slope is the straight line of E/2.

For encased structures, need to consider the cuff effect that according to the model of K.A.S.Susantha, the value rule of corresponding 7 parameters is as follows:

Concrete (being confined concrete) the pressurized extreme point of considering the sleeve pipe effect is (ε _Cc, f _Cc), design formulas is as follows:

f _cc＝f _c+mf _rp

${\mathrm{\ϵ}}_{\mathrm{cc}}={\mathrm{\ϵ}}_c[1+5(\frac{f_{\mathrm{cc}}}{f_c}-1)]---\left(4\right)$

Wherein, f _CcThe compressive strength of expression confined concrete;

ε _CcThe strain of the compressive strength correspondence of expression confined concrete;

f _cRepresent concrete prismatic compressive strength;

ε _cThe strain of expression concrete strength correspondence;

M represents empirical coefficient, gets m=4;

f _RpRepresent radially maximum lateral pressure, for being deformed into equivalent maximum lateral pressure, value is as follows more:

For circular cross-section:

$f_{\mathrm{rp}}=(v_e-v_s)\frac{2t}{D-2t}{f}_y---\left(5\right)$

Wherein, v _eSteel pipe poisson's ratio when expression has concrete to fill, value is as follows.

$v_e=0.2312+0.3582v_e^{\′}-0.1524\left(\frac{f_c}{f_y}\right)+4.843v_e^{\′}\left(\frac{f_c}{f_y}\right)-9.169{\left(\frac{f_c}{f_y}\right)}^2---\left(6\right)$

$v_e^{\′}=0.881\×{10}^{-6}{\left(\frac{D}{t}\right)}^3-2.58\×{10}^{-4}{\left(\frac{D}{t}\right)}^2+1.953\×{10}^{-2}\left(\frac{D}{t}\right)+0.4011$

Wherein: v _sRepresent the steel pipe poisson's ratio when no concrete is filled, during the steel pipe surrender, v _s=0.5;

D represents the external diameter of steel pipe;

T represents the wall thickness of steel pipe;

f _yThe yield strength of expression steel.

For quadrangle and octagonal cross-section:

Quadrangle:

$f_{\mathrm{rp}}=-6.5R\frac{{\left(f_c\right)}^{1.46}}{f_y}+0.12{\left(f_c\right)}^{1.03}---\left(7\right)$

Octagon:

$f_{\mathrm{rp}}=-35.0R\frac{{\left(f_c\right)}^{1.35}}{f_y}+0.22{\left(f_c\right)}^{1.02}---\left(8\right)$

Wherein, R represents steel pipe flakiness ratio parameter, and value is as follows;

$R=\frac{b}{t}\sqrt{\frac{12(1-v^2)}{4{\mathrm{\π}}^2}}\sqrt{\frac{f_y}{E_s}}$

f _cRepresent concrete prismatic compressive strength;

f _yThe yield strength of expression steel;

B represents the length on a limit of polygonal steel pipe;

T represents the wall thickness of steel pipe;

V represents the poisson's ratio of steel, and is desirable, v=0.3;

E _sThe modulus of elasticity of expression steel; Desirable, E _s=2.06 * 10 ⁵MPa.

Consider concrete (confined concrete) crushing point (ε of sleeve pipe effect _Cu, f _Cu), design formulas is as follows:

f _cu＝f _cc-Z(ε _cu-ε _cc)??????????????????????(9)

Wherein, f _CcThe compressive strength of expression confined concrete;

ε _CcThe strain of the compressive strength correspondence of expression confined concrete;

f _CuThe intensity of crushing place of expression confined concrete;

ε _CuThe strain of expression concrete strength correspondence;

Z represents the tangent line model of this structure of concrete descending branch, the i.e. absolute value of slope.

For circular cross-section, the design formulas of Z is:

$Z=\left\{\begin{array}{cc}0& ,R_t\left(\frac{f_c}{f_y}\right)\≤0.006\\ 1\×{10}^5{R}_t\left(\frac{f_c}{f_y}\right)-600& ,R_t\left(\frac{f_c}{f_y}\right)\≥0.006,f_y\≤283\mathrm{MPa}\\ {\left(\frac{f_y}{283}\right)}^{13.4}[1\×{10}^5{R}_t\left(\frac{f_c}{f_y}\right)-600]& ,R_t\left(\frac{f_c}{f_y}\right)\≥\mathrm{0.006,283}\mathrm{MPa}\≤f_y\≤336\mathrm{MPa}\\ 1\×{10}^6{R}_t\left(\frac{f_c}{f_y}\right)-6000& ,R_t\left(\frac{f_c}{f_y}\right)\≥0.006,f_y\≥336\mathrm{MPa}\end{array}\right.---\left(10\right)$

ε _cu＝0.025

Wherein, R _tExpression steel pipe radius-thickness ratio parameter, value is as follows;

$R_t=\sqrt{3(1-v^2)}\frac{f_y}{E_s}\frac{D}{2t}$

f _yThe yield strength of expression steel;

f _cRepresent concrete prismatic compressive strength;

D represents the diameter of round steel pipe;

T represents the wall thickness of steel pipe;

V represents the poisson's ratio of steel, and is desirable, v=0.3;

E _sThe modulus of elasticity of expression steel; Desirable, E _s=2.06 * 10 ⁵MPa.

For quadrangle, the design formulas of Z is:

$Z=\left\{\begin{array}{cc}0& ,R\left(\frac{f_c}{f_y}\right)\≤0.0039\\ 23400R\left(\frac{f_c}{f_y}\right)-91.26& ,R\left(\frac{f_c}{f_y}\right)>0.0039\end{array}\right.$

${\mathrm{\&epsiv;}}_{\mathrm{cu}}=\left\{\begin{array}{cc}0.04& ,R\left(\frac{f_c}{f_y}\right)\&le;0.042\\ 14.5{\left[R\left(\frac{f_c}{f_y}\right)\right]}^2-2.4R\left(\frac{f_c}{f_y}\right)+0.116& ,0.042<R\left(\frac{f_c}{f_y}\right)<0.073\\ 0.018& ,R\left(\frac{f_c}{f_y}\right)\&GreaterEqual;0.073\end{array}\right.---\left(11\right)$

Wherein, R represents steel pipe flakiness ratio parameter, and value is seen top formula;

f _cRepresent concrete prismatic compressive strength;

f _yThe yield strength of expression steel.

Restrictive condition and explanation:

Be f _CuCan only be at pressure zone.

For octagon, the design formulas of Z is:

$Z=\left\{\begin{array}{cc}0& ,R\left(\frac{f_c}{f_y}\right)\&le;0.018\\ 2.85\&times;{10}^{4}R\left(\frac{f_c}{f_y}\right)-513& ,R\left(\frac{f_c}{f_y}\right)>0.018\end{array}\right.$

${\mathrm{\&epsiv;}}_{\mathrm{cu}}=\left\{\begin{array}{cc}0.035& ,R\left(\frac{f_c}{f_y}\right)\&le;0.03\\ -0.566R\left(\frac{f_c}{f_y}\right)+0.052& ,R\left(\frac{f_c}{f_y}\right)>0.03\end{array}\right.---\left(12\right)$

Wherein, R represents steel pipe flakiness ratio parameter, and value is seen top formula;

f _cRepresent concrete prismatic compressive strength;

f _yThe yield strength of expression steel.

Restrictive condition and explanation:

Be f _CuCan only be at pressure zone.

Can determine 4 parameters by top formula, other 3 parameters are respectively: the loss coefficient of crushing place elastic analogy: α.The tension limit: f _t, tension softening stress-displacement stage modulus: E _tBecause the part in tension influence is less, so can get f _t=f _Cc/ 10, E _t=E ₀/ 10, or littler value.The value of α is 0＜α≤1, can get 0.1 usually according to the actual conditions adjustment.

At constitutive model and the concrete constitutive model of introducing and give steel pipe in the building model, steel and concrete lotus root close condition in each concrete filled steel tubular member by being provided with, and described constitutive model adopts the fiber elastoplastic Damage model of considering material behavior under cuff effect and the earthquake cyclic loading promptly to set up.

Preferred implementation of the present invention is, in this step, also is included in building steel core concrete column and the beam connecting node place device unit that connects, and local coordinate is set at the node place makes connector unit meet the real work situation of steel tube concrete building.Local coordinate described here is meant sets coordinate direction to connector unit, and the rotation direction when making connector unit with the node real work is consistent.

Secondly, after having made up material model, make up the geometrical model of steel tube concrete building again.Comprise: the physical dimension according to concrete filled steel tube is provided with steel pipe and concrete cross section, and then according to the locus of building steel pipe and concrete unit is assembled in FEM (finite element) model.

Step 200: adopt software that described FEM (finite element) model is calculated, that is: set the fringe conditions of building model structure and apply geological process and carry out power Elastic time-history analysis and elasto-plastic time history analysis, for the power Elastic time-history analysis, the constitutive model of steel is only got relevant elastic part, promptly, steel plasticity coefficient of intensification gets 1, be in the formula (1), R=1), for elasto-plastic time history analysis, in the constitutive model of steel, in the formula (1)

Thus, obtain the distortion situation of building under seismic stimulation according to power mileage analytical method again, the basic motive equation of Dynamic time history analysis method:

$\left[M\right]\left\{\stackrel{\&CenterDot;\&CenterDot;}{x}\right\}+\left[C\right]\left\{\stackrel{\&CenterDot;}{x}\right\}+\left[K\right]\left\{x\right\}=-\left[M\right]\left\{\stackrel{\&CenterDot;\&CenterDot;}{z}\right\}---\left(13\right)$

Wherein: [M] represents mass matrix, generally adopts the lumped mass battle array, with the mass concentration of unit to node;

[C] represents damping matrix;

[K] represents stiffness matrix, and the Stiffness Matrix of using during with static analysis is identical;

{ x} represents displacement;

Expression is subjected to displacement the speed of variation;

Expression is subjected to displacement the vector acceleration of variation;

Expression ground movement acceleration vector.

Obtain the displacement of building each point under seismic stimulation according to power mileage analytical method, thereby obtain the maximum relative storey displacement angle of each point, displacement obtains relative storey displacement angle value divided by floor height.

The specific embodiment of the present invention is, employing is in modeling software, set the fringe conditions of building model structure earlier, steel pipe and the concrete constraints set up, among the present invention, the device unit that connects at the node place, the definition local coordinate makes the realistic working condition of connector unit at the node place.For the value of node rigidity for the analog node semi-rigid characteristic, can directly not use and be rigidly connected, but in the European norm of steel structure the semirigid principle of classification of node is as the criterion, the initial stiffness that is node is less than 25 times beam line rigidity, can think that node is semi-rigid node, load again and analyze and earthquake analysis.

Step 300: anti-seismic performance assessment, that is: the maximum relative storey displacement of the building angle value by obtaining requires to assess the anti-seismic performance of building according to the maximum relative storey displacement angle limit value that in " seismic design provision in building code " encased structures is required.

Among China's " seismic design provision in building code " GB 50011-2001 requirement has been done at the relative storey displacement angle of different structure under frequently occurred earthquake and rarely occurred earthquake condition, angle of displacement must not surpass the numerical value in the table 1 between the elastic layer that the condition of frequently occurred earthquake produces.

Table 1: earthquake resistant code is to the limit value of angle of displacement between elastic layer

Structure types	??[θ e]
		Reinforced concrete frame	??1/550

Structure types	??[θ e]
		Reinforced concrete frame-seismic structural wall, earthquake resistant wall, sheet-pile-seismic structural wall, earthquake resistant wall, framework-core tube	??1/800
Tube in steel concrete seismic structural wall, earthquake resistant wall, the tube	??1/1000
		Steel reinforced concrete frame props up layer	??1/1000
Many, high-rise steel structure	??1/300

The elastoplasticity relative storey displacement angle that produces under the condition of rarely occurred earthquake must not surpass the numerical value in the table 2.

Table 2: earthquake resistant code is to the limit value at elastoplasticity relative storey displacement angle

Structure types	??[θ e]
		Individual layer reinforced concrete post framed bent	??1/30
Reinforced concrete frame	??1/50
		Reinforced concrete frame-seismic structural wall, earthquake resistant wall, sheet-pile-seismic structural wall, earthquake resistant wall, framework-core tube	??1/100
Tube in steel concrete seismic structural wall, earthquake resistant wall, the tube	??1/100
		Steel reinforced concrete frame props up layer	??1/120
Many, high-rise steel structure	??1/50

In the specific implementation process, the node of choosing the bearing place earlier imposes restriction, the outer degree of freedom of constraint seismic stimulation direction.Define load again, described load application comprises compressive load and gravity load.Apply power during the definition load on beam, gravimetric analysis step and the seismic wave analysis step is set simultaneously, the gravimetric analysis step is provided with 5 seconds, finishes loading in 1 second of beginning, and the time of the reservation of back is to weaken gradually for the concussion that makes structure.At last, import seismic wave in the step, according to the anti-seismic performance of the building dynamic response result who will obtain according to China's " seismic design provision in building code " GB 50011-2001 assessment building in seismic wave analysis.

Step 400: the seismic measures of design building thing, that is: according to the seismic measures of the assessment result design building thing of Antiseismic building performance.

In the preferred implementation of the present invention, in setting up the FEM (finite element) model step of steel tube concrete building, steel pipe and the direct constraints of concrete unit are coupling fully in the definition building model.Adopt software that described FEM (finite element) model is carried out in the calculation procedure, also comprising building model is divided grid, setting resistance coefficient and computing time.

Among the present invention, evaluation method of earthquake resistant performance of steel tube concrete building is in civilian construction that adopt steel tube concrete building or the application on the industrial construction.

Above content be in conjunction with concrete preferred implementation to further describing that the present invention did, can not assert that concrete enforcement of the present invention is confined to these explanations.For the general technical staff of the technical field of the invention, without departing from the inventive concept of the premise, can also make some simple deduction or replace, all should be considered as belonging to protection scope of the present invention.

Claims (9)

1. an evaluation method of earthquake resistant performance of steel tube concrete building is characterized in that, described building supporting member is formed by concrete filled steel tube, comprises the steps:

Set up the space fiber beam FEM (finite element) model of steel tube concrete building: the steel pipe and the concrete of concrete filled steel tube part in the building are all adopted the beam element modeling, physical dimension according to concrete filled steel tube is provided with steel pipe and concrete cross section, assemble steel pipe and concrete unit locus according to building in FEM (finite element) model, introduce and give the material structure model and the concrete material structure model of steel pipe in the building model, described constitutive model adopts the fiber elastoplastic Damage model of considering material behavior under cuff effect and the earthquake cyclic loading, be provided with that steel and concrete lotus root close condition in each concrete filled steel tubular member, by on finite element software, developing introducing.

Adopt software that described FEM (finite element) model is calculated: to set the fringe conditions of building model structure and apply geological process and carry out power Elastic time-history analysis and elasto-plastic time history analysis, thereby obtain the maximum relative storey displacement angle of building under seismic stimulation.

Anti-seismic performance assessment:, require the anti-seismic performance of assessment building according to the maximum relative storey displacement angle limit value that in " seismic design provision in building code " encased structures is required by the maximum relative storey displacement of the building angle value of obtaining.

The seismic measures of design building thing: according to the seismic measures of the assessment result design building thing of Antiseismic building performance.

2. according to the described evaluation method of earthquake resistant performance of steel tube concrete building of claim 1, it is characterized in that, in setting up the FEM (finite element) model step of steel tube concrete building, when adopting the beam element modeling, beam column is reduced to beam element, floor etc. is reduced to shell unit, the method of employing fiber beam is reduced to solid material the fibrous material of one dimension, and the influence of consideration cuff effect, consider tension and compression elastoplasticity, damage and the fracture behaviour of material under reciprocating simultaneously, develop introducing by software.

3. according to the described evaluation method of earthquake resistant performance of steel tube concrete building of claim 1, it is characterized in that, in setting up the FEM (finite element) model step of steel tube concrete building, steel pipe and the direct constraints of concrete unit are coupling fully in the definition building model.

4. according to the described evaluation method of earthquake resistant performance of steel tube concrete building of claim 1, it is characterized in that, adopting software that described FEM (finite element) model is carried out in the calculation procedure, also comprise building model is divided grid, set resistance coefficient and computing time.

5. according to the described evaluation method of earthquake resistant performance of steel tube concrete building of claim 1, it is characterized in that adopting software that described FEM (finite element) model is carried out in the calculation procedure, the described method that applies geological process comprises load application and seismic wave.

6. according to the described evaluation method of earthquake resistant performance of steel tube concrete building of claim 5, it is characterized in that adopting software that described FEM (finite element) model is carried out in the calculation procedure, described load application comprises compressive load, gravity load and seismic load.

7. according to the described evaluation method of earthquake resistant performance of steel tube concrete building of claim 1, it is characterized in that, in setting up the FEM (finite element) model step of steel tube concrete building, also be included in building steel core concrete column and the beam connecting node place device unit that connects, local coordinate be set at the node place make connector unit meet the real work situation of steel tube concrete building.

8. according to the described evaluation method of earthquake resistant performance of steel tube concrete building of claim 7, it is characterized in that in setting up the FEM (finite element) model step of steel tube concrete building, the value of node rigidity is less than 25 times beam line rigidity.

9. according to the described evaluation method of earthquake resistant performance of steel tube concrete building of above-mentioned arbitrary claim, it is characterized in that this method is in civilian construction that adopt steel tube concrete building or the application on the industrial construction.

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