Ultimate Strength and Fatigue Life of Concrete Elements Reinforced with Carbon Fiber Sheet Based on Continuum Damage Mechanics

Abstract

by using Drucker-Prager's equivalent stress in order to consider the difference between the tensile and the compressive strength of concrete. The formulated constitutive equation is implemented in the two-dimensional finite element program. The material constants are identified by using the material test results under uniaxial tension and compression and applied to the ultimate strength and fatigue life analysis. The formulation of the elasto-plastic damage constitutive equation and its identification are described in the section 2. The section 3 contains the experimental results for RC structural members under static and cyclic loading with CF-sheet. The results of finite element analysis are compared with the experimental results. An another equivalent stress is applied for the purpose of evaluating shear behavior for de-lamination or surface detachment between CF-sheet, epoxy resin and concrete in the section 4. The section 5 is the concluding remarks. ABSTRACT: Continuum Damage Mechanics (C.D.M) was applied to evaluate the mechanical behavior of concrete structural elements reinforced with carbon fiber sheet (CF-sheet) under quasi-static and cyclic loading. A constitutive equation for elasto-plastic damageable solids is formulated by using Drucker-Prager's equivalent stress and identified by the uniaxial compressive and tensile experimental results for concrete, tensile results for CF-sheet. And then finite element analyses are carried out for real-scale cantilever reinforced concrete slabs and concrete blocks with CF-sheet. Finally It was concluded that the application of C.D.M for concrete structural ultimate strength and fatigue durability comparing the experimental data and the calculation by 2-dimensional finite element method (F.E.M) was very useful.