ON THE CONSTITUTIVE RELATIONS OF ELASTICITY-CREEPS OF CONCRETE

The deformations of concrete are related to not only the loading time interval (t-τ) but also the age of concrete while loading, the relation between strain and stress takes a complex integral form. Because of the complexity of the constitutive relations, the problem of R.C. or P.C. structures can not be solved satisfactorily in a special case, the author has given the constitutive relation in the form of Laplace transformation, and presented the solving method, respect to the general constitutive relation of elasticity-creeps used in current international literatures, the author gives the algebraic (linear or nonlinear) strain-stress relations while strain and stress tend to constants when t→∞, and the linear relation while strain and stress are periodic functions when t→∞. For simplicity, only one dimensional case is considered, it is easyto extend to the three dimensional case by2. When the constitutive reintions are given, the structural problems of frames, plates and shells can be calculaed by 1and2.