In this paper, ratcheting behavior of beams subjected to mechanical cyclic loads at elevated temperature, using the rate dependent Chaboche unified viscoplastic model with combined kinematic and isotropic hardening theory of plasticity, is investigated. A precise and general numerical scheme, using the incremental method of solution, is developed to obtain the cyclic inelastic creep and plastic...

The purpose of this research was to investigate the creep behaviour of the heterogeneous Timber-UHPFRC beams. New developments have been done to further improve the structural performance, such as strengthening of the timber (glulam) beam by bonding composite material combine with an ultra-high performance fibre reinforced concrete (UHPFRC) internally reinforced with or without carbon fibre rei...

The intervertebral disc maintains a balance between externally applied loads and internal osmotic pressure. Fluid flow plays a key role in this process, causing fluctuations in disc hydration and height. The objectives of this study were to quantify and model the axial creep and recovery responses of nondegenerate and degenerate human lumbar discs. Two experiments were performed. First, a slow ...

Directionally solidified (DS) Ni-base superalloys have become a commonly used material in gas turbine components. Controlled solidification during the material manufacturing process leads to a special alignment of the grain boundaries within the material. This alignment results in different material properties dependent on the orientation of the material. When used in gas turbine applications t...

To capture the mechanical response of Ni-based materials, creep deformation and rupture experiments are typically performed. Long term tests, mimicking service conditions at 10,000 h or more, are generally avoided due to expense. Phenomenological models such as the classical Kachanov–Rabotnov (Rabotnov, 1969, Creep Problems in Structural Members, North-Holland, Amsterdam; Kachanov, 1958, “Time ...

We report the simultaneous characterization of timeand force-dependent mechanical properties of adherent cells in the physiologically relevant regime of large forces. We used magnetic tweezers to apply forces to magnetic beads bound to the cytoskeleton, and recorded the resulting deformation (creep response). The creep response followed a weak power law at all force levels. Stress stiffening an...

statement of problem: biomechanics of the human dentition is inherently complex. purpose: the aim of this study is to investigate, in vitro, the creep and the recovery of dentin under static uniaxial compressive stress conditions. materials and methods: specimens of cylindrical morphology were prepared from recently extracted non-carious lower molar teeth, such that the average tubule orientati...

Time-dependent creep analysis is presented for the calculation of stresses and displacements of axisymmetric thick-walled cylindrical pressure vessels made of functionally graded material (FGM). For the purpose of time-dependent stress analysis in an FGM pressure vessel, material creep behavior and the solutions of the stresses at a time equal to zero (i.e. the initial stress state) are needed....

OBJECTIVES To evaluate the viscoelastic properties of demineralized dentin matrix. Stress-relaxation studies were done on matrices in tension and strain elongation or creep studies were done in both tension and compression. METHODS Mid-coronal dentin disks were prepared from extracted unerupted human third molars. Disks were 0.5 mm thick for stress-relaxation or tensile creep experiments and ...

Background: The short-time creep behavior for a series of biodegradable nanocomposites which is used as implantable device into body is a crucial factor. In the current paper, we aimed to study the effect of bioactive glass nanoparticles (BGn) on creep and creep-recovery behaviors of PLA/PCL blends at different given load and different applied temperatures. Method: A series of biodegradab...