Stress–Strain Behavior of FRC in Uniaxial Tension Based on Mesoscopic Damage Model

Abstract

Fiber-reinforced concrete (FRC) is widely used in the field of civil engineering. However, the research on the damage mechanism of FRC under uniaxial tension is still insufficient, and most of the constitutive relations are macroscopic phenomenological. The aim is to provide a new method for the investigation of mesoscopic damage mechanism of FRC under uniaxial tension. Based on statistical damage theory, the damage constitutive model for FRC under uniaxial tension is established. Two kinds of mesoscopic damage mechanisms, fracture and yield, are considered, which ultimately determines the macroscopic nonlinear stress–strain behavior of concrete. The yield damage mode reflects the potential bearing capacity of materials and plays a key role in the whole process. Evolutionary factor is introduced to reflect the degree of optimization and adjustment of the stressed skeleton in microstructure. The whole deformation-to-failure is divided into uniform damage phase and local failure phase. It is assumed that the two kinds of damage evolution follow the independent triangular probability distributions, which could be represented by four characteristic parameters. The validity of the proposed model is verified by two sets of test data of steel fiber-reinforced concrete. Through the analysis of the variation law of the above parameters, the influence of fiber content on the initiation and propagation of micro-cracks and the damage evolution of concrete could be evaluated. The relations among physical mechanism, mesoscopic damage mechanism, and macroscopic nonlinear mechanical behavior of FRC are discussed.

Recent developments in utilization of nano silica in self‐compacting concrete: A review

“…The mechanical properties and durability of concrete are significantly influenced by its microstructure, where internal defects such as pores and microcracks can be detrimental. 8 This further illustrates the necessity of refining the pores and cracks in SCC. Generally, supplementary cementitious materials such as fly ash (FA), ground granulated blast furnace slag (GGBFS) and metakaolin are all micron-sized materials, and the particle size is usually tens of microns.…”

“…At the same time, researchers are constantly exploring ways to improve the overall performance of SCC. The mechanical properties and durability of concrete are significantly influenced by its microstructure, where internal defects such as pores and microcracks can be detrimental 8 . This further illustrates the necessity of refining the pores and cracks in SCC.…”

Failure Analysis of Steel Fiber-Reinforced Concrete T-Beams without Shear Stirrups

“…The Modified Drucker-Prager yield criterion is used with consideration of Lubliner Model (Lubliner, 1989) and damaged plasticity model (Lee and Fenves, 1998) for concrete and other quasi-brittle materials. This concrete damaged plasticity model has been widely used for RC and FRC application in both static and dynamic situation [31][32][33][34]. The volume fraction of SF was set to 0.76% (l f = 33 mm, d f = 0.55 mm).…”

Numerical Modelling of the Constitutive Behaviour of FRCM Composites through the Use of Truss Elements

“…In Shi et al [ 4 ], it is shown how the fibers clearly affect the matrix post-cracking behavior. While Bai et al [ 5 ] analytically studied how the tensile behavior changes as the fiber content changes, as well as the effects of this parameter on the initiation and expansion of microcracks. Studies have also been conducted on the response of FRCM material in presence of different environmental conditions [ 6 ], effects of rising damp and salt crystallization cycles [ 7 ] and with the effect of the wet-dry cycle [ 8 ].…”