Fracture mechanic modeling of fiber reinforced polymer shear-strengthened reinforced concrete beam

Abstract

a b s t r a c tA numerical method is developed to model shear-strengthening of reinforced concrete beam by using fiber reinforced polymer (FRP) composites. Tensile crack is simulated by a non-linear spring element with softening behavior ahead of the crack tip to model the cohesive zone in concrete. A truss element is used, parallel to the spring element, to simulate the energy dissipation rate by the FRP. The strain energy release rate is calculated directly by using a virtual crack closure technique. It is observed that the length of the fracture process zone (FPZ) increases with the application of FRP shear-strengthening. The present model shows that the main diagonal crack is formed at the support in the control beam while it appears through the shear span in the shear-strengthened beam. Another important observation is that the load capacity increases with the number of CFRP sheets in the shear span.

Coupled cohesive zone models for mixed-mode fracture: A comparative study

“…The non-linear problem is solved with an iterative NewtonRaphson procedure, where the global tangent stiffness matrix is obtained through the consistent linearization of the Eq. (34). The model is implemented in the finite element code FEAP (courtesy of R. L. Taylor).…”

“…CZMs have been also used to simulate fracture under static [17][18][19], dynamic [11,20], and cyclic [21,22] loading conditions, delamination of layered composites at the micro-and macro-scale [23][24][25][26], delamination between a coating and a substrate [27], debonding of fiber reinforced polymer (FRP) sheets from concrete, masonry or steel substrates [28][29][30][31][32][33][34].…”

The development of a dynamic fracture propagation model for FRP-strengthened beam-column joints

“…The crack initiates from the surface and then is propagated in the concrete material. In the proposed model, the two parameter fracture model [4] is used to predict the initial crack. The model is used by Bruno et al [36] to predict dynamic debonding in FRP strengthened with the fracture mechanics approach.…”

“…Cracks in the joint start where the beam and column intersect because of stress increase [3]. The fracture mechanics theory is the best method for predicting this type of crack [4,5].…”

Theoretical and experimental analysis of multifunctional high performance cement mortar matrices reinforced with varying lengths of carbon fibers

“…Among synthetic fibers, CFs possess exceptional physical and mechanical characteristics; therefore, they are being used as reinforcement to augment the mechanical properties (i.e. strength and ductility) of composites (11)(12)(13)(14)(15)(16)(17). Beside strength and ductility, the fibers also improve the durability characteristics of the cementitious composites by refining their microstructure and restricting the development of induced micro cracks due to shrinkage and other chemical/physical phenomenon (18)(19)(20)(21)(22)(23).…”