The ultra-high strength self-compacting concrete, UHSSCC is the new generation type of concrete with a compressive strength higher than 80MPa. The application of this type of concrete on the serviceability state in CFRP strengthened unbonded post-tensioned indeterminate I-beam is monitored and the results are compared theoretically using different standards. For this aim, full scale I-beam of 9...

This paper presents the study of strengthening R/C beams with large circular and square opening located at flexure zone by Carbon Fiber Reinforced Polymer (CFRP) laminates. A total of five beams were tested to failure under four point loading to investigate the structural behavior including crack patterns, failure mode, ultimate load and load deflection behaviour. Test results show that large o...

1. Abstract This paper concerns with the identification of multiple cracks in a beam by measurements of the damage-induced variations in the static deflection of the beam under a prescribed load condition. Each crack is simulated by an equivalent linear elastic rotational spring connecting the two adjacent segments of the beam. Sufficient conditions on the static measurements which allow for th...

Crack-growth experiments in human dentin have been performed in situ in an environmental scanning electron microscope to measure, for the first time, the crack-growth resistance curve (R-curve) for clinically relevant (<250 microm) crack extensions and to simultaneously identify the salient toughening mechanisms. "Young" dentin from donors 19-30 years in age and "aged" dentin from donors 40-70 ...

Crack deflection and the subsequent growth of delamination cracks can be a potent source of energy dissipation during the fracture of layered ceramics. In this study, multilayered ceramics that consist of silicon nitride (Si3N4) layers separated by boron nitride/silicon nitride (BN/Si3N4) interphases have been manufactured and tested. Flexural tests reveal that the crack path is dependent on th...

Fatigue failure characteristics of friction stir welds in 13mm gauge 2024-T351 plate have been assessed. Failure occurred from either the weld region (nugget/flow arm) or from the material immediately surrounding the weld. Fatigue failure from the surrounding material was essentially conventional, initiating from large S-phase intermetallic particles and growing in a macroscopic mode I manner. ...

We present a simple example of toughening mechanism in the homogenization of composites with soft inclusions, produced by crack deflection at microscopic level. We show that the mechanism is connected to the irreversibility of the crack process. Because of that it cannot be detected through the standard homogenization tool of the Γ-convergence.

Rotating shafts are important and responsible components of many machines, such as power generation plants, aircraft engines, machine tool spindles, etc. A transverse shaft crack can occur due to cyclic loading, creep, stress corrosion, and other mechanisms to which rotating machines are subjected. If not detected early, the developing shaft crack can lead to a serious machine damage resulting ...

The Magneto-Electro-Elastic (MEE) material exhibits pyroelectric and pyromagnetic effects under thermal environment. The effects of such pyroelectric and pyromagnetic behavior on vibration, buckling and deflection analysis of partially cracked thin MEE plate is presented and discussed in this paper. The aim of the study is to develop an analytical model for the vibration and geometrically linea...

Crack tip shielding phenomena, whereby the "effective crack-driving force" actually experienced at the crack tip is locally reduced, are examined with reference to fatigue crack propagation behavior in metals, composites and ceramics. Sources of shielding are briefly described in terms of mechanisms relying on the production of elastically constrained zones which envelop the crack (zone shieldi...