一種計算支座約束影響下連續(xù)組合梁徐變次內(nèi)力的解析方法

Thispapermainlyintroducesananalyticalmethodforcalculatingthecreepsecondaryinternalforceofcontinuouscompositebeamsundertheconstrainteffectofbearings.Firstly,byexplainingthebasicconceptsandassumptionsofcontinuouscompositebeams,thetheoreticalbasisofthemethodisderived.Then,usingtraditionalstaticsmethodtoanalyzethebendingcreepforceofcontinuouscompositebeams,andonthisbasis,acalculationmodelforthecreepsecondaryinternalforceofcontinuouscompositebeamsconsideringtheconstrainteffectofbearingsisproposed.Finally,theaccuracyandfeasibilityofthemethodareverifiedbyexamplecalculation.Keywords:Continuouscompositebeams,Constraintofbearings,Creepsecondaryinternalforce,Analyticalmethod連續(xù)組合梁是由兩個或多個梁組合成一個梁的結(jié)構(gòu)形式，其結(jié)構(gòu)特點是上下聯(lián)通、變形連續(xù)。具體來說，連續(xù)組合梁由眾多單元構(gòu)成，每I形等。形率、切變力分別為M(x)、θ(x)、V(x)，則可以得到下面這個式子：dV/dx=q(x)-V(x)θ(x)dM/dx=V(x)dθ/dx=M(x)/EI+其中，q(x)表示分布荷載，EI為連續(xù)組合梁的彎曲剛度。（dV/dx，dM/dx，dθ/dxV(x)，M(x)，θ(x)求一階導(dǎo)數(shù)。V(x)=C1exp(λ1x)+C2exp(λ2x)-q(x)/λ3M(x)=C1exp(λ1x)-C2exp(λ2x)+q(x)/EIθ(x)=C3sin(αx)+C4cos(αx)-M(x)/(EIα^2)其中，λ1、λ2、λ3、α為常數(shù)，C1、C2、C3、C4為待定常數(shù)。這里設(shè)支座約束對連續(xù)組合梁的正向和反向徐變次內(nèi)力的影響分別為D1、D2，V(x)=C1exp(λ1x)+C2exp(λ2x)-q(x)/λ3+D1M(x)=C1exp(λ1x)-C2exp(λ2x)+q(x)/EI+D2θ(x)=C3