General and Approximate Method for the Analysis of Linear Visco-Elastic Structures Sensitive to Second Order Effects
Abstract
Creep causes a variation of the state of stress in redundant slender R.C. structures because the deformations of the single parts are not related by affinity and depend on the applied axial load. The general method of analysis of slender R.C. frame structures in which lateral displacements are prevented leads to a set of systems of integro-differential Volterra equations and is of rather complex application. For this reason an approximate procedure is presented, based on the Age Adjusted Effective Modulus Method (AAEMM) which allows to solve the problem through a particular elastic analysis especially recommended for practical uses. Two numerical examples show the application of the Method.
Keywords
Versus Versus Versus Order Effect Versus Versus Versus Versus Compatibility Equation Concrete CreepRésumé
Le fluage donne lieu à une variation de l’état de contrainte dans les structures élancées en béton armé car les déformations des éléments structuraux ne sont pas liées par affinité et dépendent de l’intesité de léaction normale appliquée. La méthode générale d’analyse des portiques élancés en béton armé avec les noeuds qui ne sont pas déplaçables conduit à la résolution de systhèmes d’équations intégrodifférentielles de Volterra et pourtant est de très difficile application. Pour cette raison est ici présenté un procédé approché de calcul basé sur la Méthode AAEMM (Age Adjusted Effective Modulus Method) qui permet de reconduire la solution du problème à une analyse élastique particulière. Deux exemples numériques montrent l’application du procédé qui par sa simplicité se prête bien à un usage pratique.
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