In two-phase TiAl-based alloys, the coexisting 2 and phases exhibit a thermal expansion mismatch, so that increased creep rates during thermal cycling may be expected. Creep deformation of two g-TiAl-based alloys was investigated during thermal cycles between 900 and 300 or 350 C with applied tensile stresses of 32.5 or 37.0 MPa. Measured thermal cycling creep rates were compared with isotherma...

Due to the importance effect of magnetic field on the history of long-term radial and circumfer-ential creep strain and radial displacement for a three-phase nano-composite exposed to an internal pressure and placed uniform temperature, the present article subject has been pro-posed. Three-phase nano-composite made of single-walled carbon nano tubes (SWCNTs)/ glass fiber (GF)/vinylester used to...

The purpose of this study is to evaluate the long-term vertical deformations of segmented pre-tensioned concrete bridges by a new approach. It provides a practical and reliable method for calculating the amount of long-term deformation based on creep and shrinkage in segmented prestress bridges. There are various relationships for estimating the creep and shrinkage of concrete. The analytical r...

Native collagen gels are important biomimetic cell support scaffolds, and a plastic compression process can now be used to rapidly remove fluid to any required collagen density, producing strong 3D tissue-like models. This study aimed to measure the mechanical creep properties of such scaffolds and to quantify any enhanced creep occurring in the presence of cells (cell-mediated creep). The test...

The effect of molybdenum (Mo) on the microstructure and creep behavior of nominally Ti–24Al– 17Nb (at.%) alloys and their continuously reinforced SiCfiber composites (fiber volume fraction = 0.35) was investigated. Constant-load, tensile-creep experiments were performed in the stress range of 10–275 MPa at 650 C in air. A Ti–24Al–17Nb–2.3Mo (at.%) alloy exhibited significantly greater creep res...

The creep behaviors of TA2 and R60702 at low and intermediate temperature were presented and discussed in this paper. Experimental results indicated that an apparent threshold stress exhibited in the creep deformation of R60702. Meanwhile, the primary creep phase was found as the main pattern in the room temperature creep behavior of TA2. Compared with exponential law, the power law has been pr...

OBJECTIVES There have been several reports of upward creep in vancomycin MICs for Staphylococcus aureus [predominantly methicillin-resistant S. aureus (MRSA)] over recent years, but only in single centres or using contemporaneous results. We aimed to test the hypothesis of MIC creep in a multicentre study, testing all the isolates concurrently. METHODS Nineteen laboratories in the UK and Irel...

Traumatic injury to articular cartilage can lead to post-traumatic arthritis. We used a custom pendulum device to deliver a single, near-fracture impact to the medial femoral condyles of rabbits. Impact was localized to a region ∼3 mm in diameter, and impact stress averaged ∼100 MPa. Animals were euthanized at 0, 1, and 6 months after impact. Cartilage mechanical properties from impacted and sh...

Despite decades of intensive research, an entirely satisfactory constitutive relation for creep in concrete is still unavailable, even for working stress levels [I]. The rate-type creep laws with internal variables [2], although rather effective for numerical creep analysis of large structural systems, seem to be incapable of describing the aging phenomena without at least partially violating s...

Repetitive lifting in the workplace has been identified to be a cause of low back disorders. Epidemiologic data further supports an hypothesis that higher repetition rate (i.e. frequency) is an added risk factor. The objective of this study was to provide experimental data testing the above hypothesis. An in vivo feline model was subjected to 20-min of cyclic lumbar loading at frequencies of 0....