Dimensioning of concrete walls against small calibre impact including models for deformable penetrators and the scattering of experimental results

2009 ◽  
pp. 221-237 ◽  
Author(s):  
Norbert Gebbeken ◽  
Tobias Linse ◽  
Thomas Hartmann ◽  
Martien Teich ◽  
Achim Pietzsch
Keyword(s):  
Experimental Results ◽  
Concrete Walls

Evaluation of Reinforced Concrete Members Damaged by Earthquakes

1996 ◽  
Vol 12 (3) ◽  
pp. 457-478 ◽  
Author(s):  
Robert D. Hanson
Keyword(s):  
Reinforced Concrete ◽  
Experimental Results ◽  
Structural System ◽  
Concrete Walls ◽  
Lateral Capacity ◽  
Concrete Members ◽  
Reinforced Concrete Walls ◽  
Crack Repair ◽  
Seismic Repair ◽  
Repair Techniques

A number of building authorities have included or are proposing to include loss in lateral capacity of the structural system caused by earthquake damage as a basis for requiring specific degrees of seismic repair and upgrades of the damaged members or of the entire structural system. Attempts have been made to apply this criteria through the size of cracks in reinforced concrete walls. This paper reviews experimental results which demonstrate that size of wall crack is not directly related to a reduction in wall capacity. The effectiveness of various wall crack repair techniques on restoring wall characteristics is discussed.

Study on Moment-Curvature Hysteresis Relationship of Reinforced Concrete Shear Walls

2012 ◽  
Vol 166-169 ◽  
pp. 3110-3113
Author(s):  
Guang Qiang Zhou ◽  
Feng Min Xia
Keyword(s):  
Reinforced Concrete ◽  
Shear Walls ◽  
Experimental Results ◽  
Model Fit ◽  
Hysteresis Model ◽  
Concrete Walls ◽  
Modified Model ◽  
Hysteresis Curves ◽  
Reinforced Concrete Walls ◽  
Relationship Of

In order to study and improve moment-curvature hysteresis model of reinforced concrete shear walls, experiment of reinforced concrete shear walls was conducted. Based on experiment of reinforced concrete shear walls, moment-curvature relationship is deduced and moment-curvature hysteresis curves are obtained. The existing moment-curvature hysteresis models of reinforced concrete walls are discussed and improved, and the calculated moment-curvature hysteresis curves with the modified model fit well with experimental results.

Seismic performance of squat thin reinforced concrete walls for low-rise constructions

2020 ◽  
Vol 36 (3) ◽  
pp. 1074-1095 ◽  
Author(s):  
Matías A Hube ◽  
Hernán Santa María ◽  
Orlando Arroyo ◽  
Alvaro Vargas ◽  
Javier Almeida ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Seismic Performance ◽  
Latin American ◽  
Seismic Behavior ◽  
Nonlinear Models ◽  
Single Layer ◽  
Experimental Results ◽  
Concrete Walls ◽  
Reinforced Concrete Walls ◽  
Web Reinforcement

Thin reinforced concrete (RC) walls with single layer reinforcement have been used for houses and buildings in several Latin American countries. Although some design codes include recommendations for squat thin walls in low-rise constructions, its seismic performance has not been validated adequately in past earthquakes. This article presents the results of an experimental campaign of nine full-scale specimens conducted to characterize the influence of the steel type, the reinforcement ratio, and the wall thickness on the seismic behavior of squat thin RC walls with single layer reinforcement. Both welded wire and deformed bars were used as web reinforcement. Experimental results are used to develop nonlinear models to assess the seismic behavior of a prototype two-story house with welded wire reinforcement and deformed bars by means of incremental dynamic analyses. The experimental results show that the type of steel has the largest influence on wall seismic performance. The numerical results suggest that RC walls with single layer reinforcement are suitable for housing applications up to two stories in high seismicity regions, particularly walls detailed with deformed bars.

Diagnostics of Gold Laser Plasmas

1988 ◽  
Vol 102 ◽  
pp. 357-360
Author(s):  
J.C. Gauthier ◽  
J.P. Geindre ◽  
P. Monier ◽  
C. Chenais-Popovics ◽  
N. Tragin ◽  
...  
Keyword(s):  
Experimental Results ◽  
Pure Gold ◽  
Electronic Temperature ◽  
X Ray ◽  
Laser Plasmas ◽  
Collisional Radiative Model ◽  
Radiative Model

AbstractIn order to achieve a nickel-like X ray laser scheme we need a tool to determine the parameters which characterise the high-Z plasma. The aim of this work is to study gold laser plasmas and to compare experimental results to a collisional-radiative model which describes nickel-like ions. The electronic temperature and density are measured by the emission of an aluminium tracer. They are compared to the predictions of the nickel-like model for pure gold. The results show that the density and temperature can be estimated in a pure gold plasma.

Observation of Phase Contrast Images in STEM and CTEM Modes by Using 100 kV Field Emission Electron Gun

1974 ◽  
Vol 32 ◽  
pp. 390-391
Author(s):  
Y. Harada ◽  
T. Goto ◽  
H. Koike ◽  
T. Someya
Keyword(s):  
Field Emission ◽  
Phase Contrast ◽  
Image Formation ◽  
Fresnel Diffraction ◽  
Experimental Results ◽  
Electron Gun ◽  
Scanning Microscopy ◽  
Emission Electron ◽  
Lattice Images

Since phase contrasts of STEM images, that is, Fresnel diffraction fringes or lattice images, manifest themselves in field emission scanning microscopy, the mechanism for image formation in the STEM mode has been investigated and compared with that in CTEM mode, resulting in the theory of reciprocity. It reveals that contrast in STEM images exhibits the same properties as contrast in CTEM images. However, it appears that the validity of the reciprocity theory, especially on the details of phase contrast, has not yet been fully proven by the experiments. In this work, we shall investigate the phase contrast images obtained in both the STEM and CTEM modes of a field emission microscope (100kV), and evaluate the validity of the reciprocity theory by comparing the experimental results.

A new dissociation mode for dislocations in silicon

1978 ◽  
Vol 36 (1) ◽  
pp. 346-347
Author(s):  
A. Ourmazd ◽  
G.R. Booker ◽  
C.J. Humphreys
Keyword(s):  
Detailed Examination ◽  
Experimental Results ◽  
Dislocation Network ◽  
Weak Beam ◽  
Phosphorus Doped

A (111) phosphorus-doped Si specimen, thinned to give a TEM foil of thickness ∼ 150nm, contained a dislocation network lying on the (111) plane. The dislocation lines were along the three <211> directions and their total Burgers vectors,ḇt, were of the type , each dislocation being of edge character. TEM examination under proper weak-beam conditions seemed initially to show the standard contrast behaviour for such dislocations, indicating some dislocation segments were undissociated (contrast A), while other segments were dissociated to give two Shockley partials separated by approximately 6nm (contrast B) . A more detailed examination, however, revealed that some segments exhibited a third and anomalous contrast behaviour (contrast C), interpreted here as being due to a new dissociation not previously reported. Experimental results obtained for a dislocation along [211] with for the six <220> type reflections using (g,5g) weak-beam conditions are summarised in the table below, together with the relevant values.

Multislice calculations of RHEED patterns from vicinal Si (001)

1993 ◽  
Vol 51 ◽  
pp. 1000-1001
Author(s):  
Scott Lordi
Keyword(s):  
Misorientation Angle ◽  
Incident Angle ◽  
Incident Beam ◽  
Experimental Results ◽  
Bragg Condition ◽  
Vicinal Surfaces ◽  
Kinematic Theory ◽  
Step Edges

Vicinal Si (001) surfaces are interesting because they are good substrates for the growth of III-V semiconductors. Spots in RHEED patterns from vicinal surfaces are split due to scattering from ordered step arrays and this splitting can be used to determine the misorientation angle, using kinematic arguments. Kinematic theory is generally regarded to be inadequate for the calculation of RHEED intensities; however, only a few dynamical RHEED simulations have been attempted for vicinal surfaces. The multislice formulation of Cowley and Moodie with a recently developed edge patching method was used to calculate RHEED patterns from vicinal Si (001) surfaces. The calculated patterns are qualitatively similar to published experimental results and the positions of the split spots quantitatively agree with kinematic calculations.RHEED patterns were calculated for unreconstructed (bulk terminated) Si (001) surfaces misoriented towards [110] ,with an energy of 15 keV, at an incident angle of 36.63 mrad ([004] bragg condition), and a beam azimuth of [110] (perpendicular to the step edges) and the incident beam pointed down the step staircase.

Appropriation des Savoirs et Mémoire Collective

2013 ◽  
Vol 72 (2) ◽  
pp. 71-78
Author(s):  
Sophie Richardot
Keyword(s):  
Collective Memory ◽  
Factorial Analysis ◽  
Experimental Results ◽  
Ancient History ◽  
Historical Events ◽  
Memoire Collective ◽  
Obedience To Authority

The aim of this study is to understand to what extent soliciting collective memory facilitates the appropriation of knowledge. After being informed about Milgram’s experiment on obedience to authority, students were asked to mention historical or contemporary events that came to mind while thinking about submission to authority. Main results of the factorial analysis show that the students who do not believe in the reproducibility of the experimental results oppose dramatic past events to a peaceful present, whereas those who do believe in the reproducibility of the results also mention dramatic contemporary events, thus linking past and present. Moreover, the students who do not accept the results for today personify historical events, whereas those who fully accept them generalize their impact. Therefore, according to their attitude toward this objet of knowledge, the students refer to two kinds of memory: a “closed memory,” which tends to relegate Milgram’s results to ancient history; and an “open memory,” which, on the contrary, transforms past events into a concept that helps them understand the present. Soliciting collective memory may contribute to the appropriation of knowledge provided the memory activated is an “open” one, linking past to present and going beyond the singularity of the event.

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