Abstract
On the basis of consideration on dynamic deformation test data of geomaterial, the author defined a physical parameter, namely, Momentary Deformation Modulus abbreviated as MDM that means the secant stiffness at very small strain near the origin in the every moment the latest maximum strain comes out under cyclic loading. Then, the author proposed a cyclic stress-strain model named MDM model that uses a skeleton function considering the maximum strain dependent change of the Momentary Deformation Modulus, applying the Masing law to the skeleton function. Besides, the author proposed a new hysteresis law and a determination procedure of parameters of the proposed model, and made the difference clear between the past hysteresis models and the proposed model. Furthermore, the author showed the flexible applicability of the proposed model by means of evidence that it could simulate the real stress-strain relationships of the quite soft soil and the extremely hard steel.
