A BENDING DAMAGE THEORY FOR BEAMS UNDER PURE BENDING LOADS

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Based on the basic assumptions of pure bending damage of beams, a simplebending damage theory is proposed, in which the definition of bending damage variable is defined by reduction of moment of inertia similar to that of tensile damage variable by reductionof loading area by L. M. Kachanov (1958). For simplicity of application in engineering, theevolution law of bending damage variable can be adapted as a simple form. As an example,an exact bending damage inalysis of a beam for creep pure bending is made. The calculatingresults are compared with the results obtained by Kachanov' S tensile damage theory (1986).Moreover, in addition to determination by experiments (similar to the measurements of tensile damage, J. Lemaitre, 1987), the material' S constants of the simple bending damagemodel can be determined in first approximation to Kachanov' S tensile damage model.