Accurate prediction of the fracture occurrence of high strength materials is always the hot spot in the research field of metal-forming process. Appropriate material model is the key issue which can accurately describe the mechanical forming behavior under different forming conditions. However, advanced fully coupled damage/behavior models are heavy to use by engineers and have a high cost in term

The present paper proposes a new analytical model for predicting the effective stiffness of composite laminates with fiber breaks and transverse cracks. The model is based on continuum damage mechanics and the classical laminate theory. We derived damage variables describing stiffness reduction due to fiber breaks and its maximum value during ultimate tensile failure from the global load-sharing model

A damage model is developed and validated with experimental data for the non-linear mechanical behavior of SiC/SiC composite materials in nuclear applications. Cyclic thermal and mechanical loading associated with neutron irradiation effects of these composites leads to wide-spread and progressive micro-cracking that leads to loss of thermal conductivity and further enhancement of thermo-mechanical

In the present study, Kachanov–Rabotnov continuum damage model has been employed to describe the steady state and tertiary creep deformation and damage behaviour of 316L austenitic stainless steel with different nitrogen contents of 0.07, 0.11 and 0.22 wt%, at 923 K. For all the nitrogen contents, the model appropriately predicts the creep strain–time data, creep rupture strain and rupture life. The

It has been well recognized that unsaturated natural loess shows significant volume contraction upon wetting due to its metastable internal structure. But the structural effect on stress–strain relationship of saturated natural (undisturbed) loess is much less explored. Few attempts have been made in proposing a constitutive model for saturated natural loess. This study presents both laboratory tests

A novel contour integral approach termed Medg is introduced for computation of the surface energy required for the formation of multiple edge cracks. The method is developed by reinterpretation of the conventional M-integral with deliberate delimitation of integration contour and selection of coordinate origin. Due to path independence, this method is efficient, easy to implement by using finite elements

This article deals with damage computation of heterogeneous structures containing locally periodic micro-structures. Such heterogeneous structure is extremely expensive to simulate using classical finite element methods, as the level of discretisation required to capture the micro-structural effects is too fine. The simulation time becomes even higher when dealing with highly non-linear material behaviour

In the framework of continuum damage mechanics, a new damage-coupled cyclic plastic model is proposed to describe the nonlinear evolution of whole-life ratchetting and its dependence on the stress level. The characteristic that the damage evolution rate of U75V heat-treated steel decays in the initial load cycles is considered by introducing a modified term into classic damage evolution equation. A

A series of experiments subjected to uniaxial and non-proportionally multiaxial cyclic loadings were performed to investigate the ratcheting responses of SA508 Gr.3 steel at room and elevated temperatures. The influences of different stress levels and nonproportional loading paths on the damage-coupled ratcheting responses were discussed. From experimental results, cyclic softening characteristic and

Flexible fabrics have been widely used in body armor designs. Here we report ballistic impact damage of stacked cross-plied composite fabric and cross-plied laminated panels. The ballistic impact behaviors of stacked cross-plied composite fabric and cross-plied laminated panel have been tested with fragment-simulating projectiles under the strike velocity 550–600 m/s to explore the influence of the

Growing awareness of sustainability in the landfill cover system has increased the use of biochar amendment for degraded landfill surface soils. Hydraulic and vegetative benefits of biochar on cover soil have been studied in the past, while ignoring mechanical characteristics, which is important to understand progressive failure of landfill infrastructure. In this study, the mechanical characteristics

The (micro-) cracks or (micro-) voids will lead to the damage of concrete material. A stochastic micromechanical framework is proposed to investigate the damage healing of the unsaturated concrete with the electrochemical deposition method. Stochastic micromechanical representations are presented based on the material’s random microstructures. Differential scheme-based multilevel homogenization procedures

Stress drops in stress–strain constitutive curves of intact brittle rocks under high confining pressure have great significance for evaluating the earthquake mechanism and the safety of deep underground engineering. Microcrack growth in intact rock strongly influences the stress drops. However, the theoretical model of microcrack growth-dependent multi-stress drops rarely is proposed in stress–strain

In this paper, a time-dependent tensile constitutive model of long-fiber-reinforced unidirectional ceramic-matrix minicomposites is developed considering the interface and fiber oxidation. The relationship between the time-dependent tensile behavior and internal damage is established. The damage mechanisms of time-dependent matrix cracking, fiber/matrix interface debonding, fiber failure, and the oxidation

Firstly, an X-ray diffraction test is carried out to investigate brittle rock specimens’ composition, and a triaxial compression test is conducted to study the deformation behaviors and mechanical properties. Then, assuming that the rock material is able to be divided into the elastic part satisfying the Hooke’s law and the damage part where rock strength follows lognormal distribution, this paper

In the present study, a novel methodology of damage modeling is introduced to predict damage propagation in fibrous composite materials according to the plastic strain energy density induced in the lamina only. The importance of the new damage-model is the ability to assess damage-evolution in fibrous composite laminae irrespective of stress-state and fiber-orientation angle. An energy-based model

Pore-like flaws, which are commonly encountered in brittle rock, play an important role in the engineering performance of structures constructed in or on rock. Experimental and numerical investigations of micro-cracking mechanism of rock containing a pore-like flaw can enhance our knowledge of rock damage/failure from a microscopic view. In this study, the influences of a two-dimensional circular pore-like

In this study, a rigorous constitutive model within the framework of thermodynamics is formulated to describe the coupling process between irreversible deformation and anisotropic damage of rock materials. The coupling effect is reflected based on the “two-surface” formulation. The plastic response is described by a yield function while the anisotropic damage is defined by a novel exponential damage

With advantages in sustainability, low thermal conductivity, and self-weight, the foamed cement-based composites have captured tremendous attention in various low strength structural and nonstructural applications. This paper aimed to investigate the effects of the short polypropylene fibers on the quasi-static compression performance of the ultra-low-weight foamed cement-based composites. The results

The experimental results show that the creep properties of the rocks are affected by the initial damage, and the damage evolution also has a significant impact on the time-dependent properties of the rocks during the creep. However, the effects of the initial damage and the damage evolution are seldom considered in the current study of the rocks' creep models. In this paper, a new nonlinear creep damage

The present paper presents a theoretical formulation of different self-healing variables. Healing variables based on the recovery in elastic modulus, shear modulus, Poisson's ratio, and bulk modulus are defined. The formulation is presented in both scalar and tensorial cases. A new healing variable based on elastic stiffness recovery in proposed, which is consistent with the continuum damage-healing

The paper presents experimental and numerical characterization of damage evolution for ion-irradiated materials subjected to plastic deformation during nano-indentation. Ion irradiation technique belongs to the methods where creation of radiation-induced defects is controlled with a high accuracy (including both, concentration and depth distribution control), and allows to obtain materials having a

Elastic–plastic damage of a ductile epoxy resin is investigated for the first time in the configuration of semicircular bend specimen weakened by U-shaped notches under mixed mode I/II loading conditions. U-notched specimens are prepared from the characterized epoxy material with different notch rotation angles and notch tip radii. Load-carrying capacities of the U-notched specimens are experimentally

The mechanical properties of rock-like materials always attract the interest of many researchers. In this paper, we study the influence of specimen cross-section shape on uniaxial compressive strength as well as their deformation, damage and failure characteristics by uniaxial compression tests. The diameter and height of circular cross-section specimens are 50 and 100 mm, respectively, and the height

This paper is intended to examine the dislocation and adiabatic shear mechanisms of 7055 aluminum alloy during cutting process with different cutting speeds. The result indicates that, at low cutting speeds, isometric dislocation cells appear, the dislocation cells are interconnected into dislocation cell blocks, and the dislocation movement is controlled by thermal activation; at high cutting speeds

The probabilistic behavior of the fiber-reinforced concrete is usually represented by the common probability density functions, which will lead to the biased results. This study aims to develop a stochastic multiphase micromechanical framework with Legendre orthogonal polynomial to investigate the unbiased probabilistic behavior of the fiber-reinforced concrete's moduli. The different phase volume

To study the dynamic behavior and impact damage and failure of concrete materials and structures, a dynamic damage model was reformulated under the framework of the non-local peridynamic theory in this paper. The stretch rate of material bonds, equivalent to the strain rate in classical continuum mechanics, was introduced, and a rate-dependent peridynamic model describing the dynamic damage and failure

The whole shear deformation of rock joints significantly affects the long-term behavior and safety of engineering projects. In this paper, a new damage constitutive model related to the Weibull distribution and statistical damage theory is proposed. This model considers the shear stiffness degradation, post-peak softening, and residual phase of rock joints in the whole shearing process. Main works

The ultimate failure of the woven composite pipes has been investigated using progressive damage modeling. The composite pipe specimens were made of (E) glass plain weave fabrics according to the ASTM D2290 standard. The hoop strength of these specimens has been obtained from the tensile tests. The damage initiation and propagation of composite pipe have been predicted by a numerical multi-scale method

Fiber metal laminates have been successfully applied in military aircrafts, armor vehicles and other modern engineering industries as protective structures due to their outstanding impact resistant properties. Prediction of the ballistic performance and investigation on the damage mechanism of the fiber metal laminates under general oblique impact conditions still remain a very challenging issue. In

Precast concrete frame structures are widely adopted around the world due to their various advantages, so it is important to study their seismic performance. The development of damage mechanics has enabled us to accurately investigate the typical failure mechanisms of precast structures. This paper presents three of the most commonly used modeling approaches based on damage mechanics for analysis of

A detailed micromechanical finite element analysis methodology is presented to predict the transverse tensile (fiber perpendicular) failure behavior of a unidirectional (UD) glass fiber-reinforced plastic composite ply. In order to understand the constituent-level stress–strain and damage behavior, finite element analysis is accomplished using representative volume element (RVE) that consists of random

The “Damage Mechanics of Materials and Structures” special issue in the International Journal of Damage Mechanics (IJDM) is motivated by the Third International Conference on Damage Mechanics (ICDM-3) that was held in Tongji University, Shanghai, China on 4–6 July 2018. The competitively selected papers in this special IJDM issue encompass a variety of state-of-the-art mechanical and damage formulations

The effect of radiation on silica has attracted significant attention due to its potential application where radiation exists. However, the nature of the atomistic defects of quartz formed during the radiation-induced damage at high temperatures has not been fully elucidated. Molecular dynamics is adopted to investigate the damage-healing behavior of the quartz at high temperatures in this research

Cables are the most sensitive components in cable-supported bridges, and the failure of cables is usually caused by the degradation of mechanical properties of internal wires. Based on Faraday's law and the rates of microcrack initiation and propagation, a multi-scale corrosion fatigue damage model was developed to describe the damage evolution in the stages of pit growth and microcrack propagation

A method for determining the critical value of the Cockcroft–Latham damage criterion is presented using the example of R260 railway steel. The determinations were performed using a rotary compression test specially developed for that purpose. The main object of the proposed test was to provide the best possible representation of the state of stress generated by cross-wedge rolling. The rotary compression

A micromechanics-based constitutive model is formulated to describe the nonlinear elastoplastic behaviors of frozen sands. In the model, frozen soils are conceptualized as two-phase materials, in which the first phase is regarded as virgin/undamaged frozen soil specimen including the components of soil particles, ice crystals, and partial water with elastic–brittle behaviors (bonded elements), and

Three-dimensional braided composite materials have been widely applied to engineering structure manufacturing. It is of a great importance to characterize the impact damage of the three-dimensional braided composite under various temperatures for optimizing the engineering structure. Here we conducted transverse impact deformation and damage of three-dimensional braided composite beams with different

Fire represents one of the significant hazards encountered by civil infrastructures, and thus providing appropriate fire safety measures is a major requirement in a building design for ensuring the safety of the occupants. Minimizing fire-induced damage and collapse of structural systems are the primary objectives in the design of concrete structures. An experimental investigation has been carried

The paper presents a model of creep damage development in polycrystalline material. The model operates at two scales: micro and macro. The microscale is appropriate for simulation of the damage development phenomenon. Engineering structures operate and experimental tests are performed at the macroscale. For a polycrystalline material, damage development is strictly dependent on the structure of the

Creep–fatigue experiments were performed at 850℃ on bare and salt-coated directionally solidified Ni-based superalloy DZ125. Experimental test results showed that the salt-coated sample exhibited lower lifetime than that of the bare sample under all stress conditions. This reduction is found to correlate directly with the higher probability of crack initiation, due to surface micro-structural degradation

A fatigue–oxidation–creep damage model that can take into account the effect of multiaxial cyclic feature on the damage mechanism is proposed under axial-torsional thermo-mechanical fatigue loading. In the proposed model, the effects of non-proportional additional hardening on fatigue, oxidation, and creep damages are considered, and the variation of oxidation damage under different high temperature

We investigated three different automated methods for identification and quantification of meso-scale damage on single-layer composite laminates subjected to ballistic impact by a 5.5 mm (0.22 caliber) right circular cylindrical steel projectile. These methods were based on the combined use of high-resolution optical imaging, fluorescence microscopy, and image detection software. High-resolution images

To study the creep property of salt rock, uniaxial compression creep tests on salt rock specimens were carried out. The test results indicate that there is no steady creep of the salt rock used in this test in a strict sense. Even in the steady creep stage, the creep rate of salt rock changes continuously over time, but with a relatively smaller change range. When the axial stress does not exceed 9

The problem of compression of an isotropic medium by a periodic system of variable width slits comparable with elastic deformations is considered. The slit faces are under internal pressure. It is considered that the slits have end zones wherein material's tractions act. It is accepted that interaction of the slit's surface under applied loads may reduce the formation of contact zones of their surfaces

The crack opening and crack sliding displacements of both faces of an intralaminar crack are the main parameters defining the significance of each crack in laminate stiffness degradation, according to the previously published GLOB-LOC approach for symmetric laminates with an arbitrary number of cracks in all plies. In the exact stiffness expressions of this approach, the crack density is always multiplied

The paper discusses an anisotropic continuum damage model for concrete and its numerical implementation into a finite element program to provide an efficient approach suitable for boundary-value problems analyzing nonlinear concrete behavior. The phenomenological continuum approach is based on kinematic description of damage. Irreversible deformation behavior as well as volume increase of material

In order to compute the process from the damage accumulation to failure of steel structures under extreme cyclic loading and temperature, a multi-scale fatigue–creep damage model has been developed. Based on the balance of micro-crack number density theory, the multi-scale fatigue damage model has been established using generalized self-consistent method. In the fatigue damage model, the scatter of

Many fatigue damage models have been investigated based on the S–N curve or modified S–N curve; however, a number of them require additional efforts to determine the material parameters or do not consider the loading history (loading interactions, loading sequences, loading levels, etc.). These limitations can result in extreme deviations for estimating the fatigue life in real-world scenarios. To

A split Hopkinson pressure bar is adopted to test the dynamic mechanical behavior of frozen soil at different temperatures and high strain rates. An aluminum sleeve is used as a passive confining pressure device. Comparing the results of this test with those under the uniaxial state shows that besides the temperature and strain rate effects, frozen soil exhibits obvious stress strengthening characteristics

This paper presents an experimental research on the length and shape of the fracture process zone of rocks under mode I, mixed mode (I + II) and mode II loading conditions for different geometries of cracked specimens made of two types of rocks, using the digital image correlation approach. Single edge notch bending (SENB) and semi-circular bend specimens are the two geometries considered. In order

In this study, the performance of braided composite tubes under low-velocity transverse impact loading at mid-span was investigated using both numerical and experimental methods. Three types of braided composite tubes with different braiding angles (30°, 45°, and 60°) were manufactured. The transverse punch behavior of the tubes was examined on a low-velocity imspact test bench. A meso-level finite