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[en] The article Numerical evaluation of test setups for determining the shear strength of masonry, written by Shenghan Zhang, Nicolas Richart and Katrin Beyer, was originally published online without Open Access.
[en] This thesis deals with the short wavelength collective dynamics of dense binary fluid mixtures. The analysis shows that at the level of linearized generalized hydrodynamics, the longitudinal modes of the system separates essentially into two parts - one involves the coupling of partial density fluctuations of the two species and the other involves coupling of longitudinal momentum and temperature fluctuations. The authors have shown that the coupling of longitudinal momentum and temperature fluctuations leads to an adequate description of sound propagation in such systems. In particular, they show that structural disorder controls the trapping of sound waves in dense mixtures. The coupling of the partial density fluctuations of the two species leads to a simple description of the partial dynamic structure factors. The results are in agreement with the molecular dynamics simulations of soft sphere mixtures. The partial density fluctuations are the slowest decaying fluctuations on molecular length scales and it turns out that nonlinear coupling of these slow modes leads to important corrections to the long time behavior of the time correlation functions determining the shear viscosity in dense mixtures
[en] Lap splice is considered the best method of jointing reinforcing deformed steel bars (rebars) in reinforced concrete members. Large shear walls are used in nuclear power plants. The purpose is to seize the influencing parameters on the structural characteristics of lap splice in shear wall. Authors have developed a test method by which lap spliced specimens at shear stress zones are subjected to tensile force at both ends. 19 specimens were tested and arranged for testing 7 parameters. (orig./HP)
[en] When a (011) plane of a single crystal of molybdenum undergoes a shear stresses in whatever direction Δ, the macroscopic shear takes place along a direction Δ'. It can be considered as the result of two shear deformations along (111) directions. The stresses which are required to produce the shear deformation in the (111) directions depend on the direction of the shear stress and do not obey the law of the critical shear stress
[fr]Lorsqu'un plan du type (011) d'un monocrystal de molybdene est sollicite par un cisaillement selon une direction Δ quelconque, le glissement macroscopique a lieu selon une direction Δ'. Il est la resultante de deux glissements conjugues selon des directions de type (111). Les contraintes necessaires au glissement de ces directions (111) sont dependantes de la direction de sollicitation et ne satisfont pas a la loi de cision critique
[en] A mechanism is proposed for catastrophic shear in niobium crystals; it involves b=1/2a <111> rather than b=a <100> dislocations. Deformation occurs by a form of kinking which begins as diffuse necking followed by localised necking and geometrical softening
[en] The displacive transformation classification proposed at ICOMAT 79 is reviewed in light of recent progress in mechanistic understanding. Issues considered include distinctions between shuffle transformation vs. self-accommodating shear, dilatation vs. shear-dominant transformation, and nucleated vs. continuous transformation. (orig.)
[en] The paper reports the results of 105 in situ tests performed on undamaged masonry panels carried out by the authors during the last 20 years. The panels, mostly stone and brickwork masonry, were selected in 59 buildings in Tuscany (Italy) and had different texture and section typologies. The tests, aimed to evaluate both shear strength and deformability parameters, included 50 diagonal tests and 55 flat-jack tests. Main results of tests are supported by a qualitative description of the masonry textures. As a general result, a good agreement was found between the experimental shear strength and the range of values provided by the Italian Building Code. On the contrary, significant differences were obtained with respect to the longitudinal and the shear modules of elasticity. This is probably due to the high sensibility of these values to the method used to treat the data records. The results here presented, together with further data on the subject, are included in a web page named “Tuscany Masonry DataBase”. The database constitutes an effective set of experimental results that can be employed to extract reference values (both quality and mechanical properties) for masonry typologies at local level.
[en] Experimental analyses have been carried out on tuff masonry specimens in order to investigate the structural behaviour of historical buildings in the Naples area (Southern Italy). Spandrels of post-medieval buildings (late XVI to early XX century) have been analysed, with emphasis on morphological characteristics according to chronological indicators. Results of the experimentation on scaled models (1:10) are discussed and the better behaviour of historical masonry typologies on respect to the modern one is highlighted. Comparison with theoretical formulations of ultimate shear resistance are provided too
[en] Release waves from the back of a plate slap experiment are used to estimate the longitudinal modulus, bulk modulus and shear strength of the metal in the state produced by a symmetric collision. The velocity of the interface between the metal target and a window material is measured by the axially symmetric magnetic (ASM) probe. Wave profiles for initial states up to 90 GPa for 2024 Al and up to 150 GPa for Cu have been obtained. Elastic perfectly-plastic (EPP) theory cannot account for the results. A relatively simple quasi-elastic plastic (QEP) model can