Statistical Damage Constitutive Model for High-Strength Concrete Based on Dissipation Energy Density

Abstract

To study the energy evolution law and damage constitutive behavior of high-strength concrete based on the conventional triaxial compression tests of C60 and C70 high-strength concrete subjected to five different confining pressures, the failure characteristics of high-strength concrete are analyzed at different confining pressures, and the evolution of the input energy density, elastic strain energy density, and dissipation energy density with axial strain and confining pressure are quantified. Combined with a continuous damage theory and non-equilibrium statistical method, the ratio of dissipation energy density of concrete to dissipation energy density corresponding to peak stress is used as the mechanical parameter. Assuming that the mechanical parameter obeys the Weibull distribution laws, the statistical damage variable describing the damage characteristics of concrete were derived. According to the Lemaitre strain equivalent principle, the damage variable is introduced to the generalized Hooke law to establish the statistical damage constitutive model for high-strength concrete. The results show that: (1) the input energy density and dissipation energy density increases with the increase of axial strain, while the elastic strain energy density increases first and then decreases as a function of the axial strain and reaches the maximum value at the peak stress; (2) the input, elastic strain, and dissipated energy densities corresponding to the peak stress of the two high-strength concretes all increase as a function of confining pressure, and the elastic strain energy density corresponding to the peak stress increases linearly as a function of the confining pressure; (3) the statistical damage constitutive model results of C60 and C70 high-strength concrete are in good agreement with the test results, and the average relative standard deviations are only 3.64% and 3.99%. These outcomes verify the rationality and accuracy of the model.

Analysis of Uniaxial Compression Mechanical Properties of Rubber Powder Recycled Coarse Aggregate Concrete Based on Strain Energy Theory

“…When concrete is in uniaxial compression in the unconfined pressure state, the total, elastic, and dissipated energy absorbed by the concrete increases with increasing stress before the peak stress [49]. e elastic strain energy is the energy that accumulates within a concrete specimen when it undergoes elastic deformation and is reversible because the elastic deformation is reversible [50]. Dissipated energy mainly consists of: (a) the surface energy consumed during crack opening, development, and penetration; (b) the plastic strain energy consumed by the irreversible plastic deformation of the concrete specimen; and (c) the thermal energy generated by the frictional slip between the cracks and various radiative energies [51,52].…”

“…As the strain increases to ε d , damaged cracks within the concrete proliferate and intertwine, leading to an increase in dissipated energy. e crack tip produces acoustic emission energy due to the stress concentration effect, accompanied by irrecoverable plastic strain energy and various sources of radiant energy [50]. At this point, the proportion of dissipated energy is increasing and the proportion of elastic energy is decreasing.…”

Study on Energy Evolution and Damage Constitutive Model of Siltstone

“…The mechanical properties of rocks are particularly important for the stability analysis of surrounding rocks [3,4], so it is necessary to analyze the mechanical properties of rock under different stress states. Establishing the constitutive model of rock, using statistical damage theory, has become one of the important methods to study the nonlinear mechanical properties of rock [5][6][7][8][9].…”

New Frontiers in Cementitious and Lime-Based Materials and Composites

“…However, if the filler loading exceeds the 20% critical threshold, the material becomes extremely porous, with detrimental effects on the mechanical strength. This experimental study is particularly useful to foster understanding on how coastal cemented soils may attain satisfactory properties for real-scale applications; • Zhang et al [23] focus their attention on high-strength concrete and give an insight into its complex constitutive relations and failure behaviour under different stress states, both experimentally and numerically. Firstly, Zhang et al [23] conduct conventional triaxial compressive tests on different high-strength concrete samples, and analyse the failure modes as a function of the applied confining pressure.…”

“…This experimental study is particularly useful to foster understanding on how coastal cemented soils may attain satisfactory properties for real-scale applications; • Zhang et al [23] focus their attention on high-strength concrete and give an insight into its complex constitutive relations and failure behaviour under different stress states, both experimentally and numerically. Firstly, Zhang et al [23] conduct conventional triaxial compressive tests on different high-strength concrete samples, and analyse the failure modes as a function of the applied confining pressure. Secondly, the experimental findings are discussed according to a statistical damage constitutive model based on the thermodynamic theory.…”