Large deformation structure analysis of complex telescopic boom system for engineering machinery

Author(s):  
Lei Xu ◽  
Xiaodong Xu ◽  
Zhijian Tian ◽  
Cuijun Jin
2017 ◽  
Author(s):  
Vladimir V. Kibitkin ◽  
Andrey I. Solodushkin ◽  
Vasily S. Pleshanov

2007 ◽  
Vol 49 (3) ◽  
pp. 337-361 ◽  
Author(s):  
Luc M. Beaudry ◽  
Gilbert Prichonnet

ABSTRACT This paper presents a model for the genesis of De Geer moraines in the Chapais and Radisson areas, Québec. The model is mainly based on faciès and deformation structure analysis. Three facies associations have been identified: (1) sorted sediments that form foreset laminations dipping downglacier. Till lenses or glacial diamictons are found within the sorted sediments or form a surficial layer on the proximal side of the sections; (2) a non-fissile and poorly compacted till overlies and deforms sorted sediments. Laminae of finely sorted sediments may be incorporated in the till; (3) a fissile and compact till commonly lies on the basal till sheet. All three facies associations feature deformation structures (faults, folds, load and drag structures) which indicate an upglacier origin. The model proposed is an emplacement of De Geer moraines in bottom crevasses by an active glacier. In areas where meltwaters were channelized, sediments accumulated in the crevasses as foreset laminations. Till filled the crevasses in areas remote from meltwater flow. Glacial activity remobilized the basal till locally and pushed it toward bottom crevasses located downglacier, or overturned large layers of till. Finally, in areas located even further laterally, meltwaters had almost no effect and the moraines were formed by plastering of till in the crevasses. The three faciès associations are part of a continuum beginning with the moraines composed of sorted sediments and grading laterally into the moraines formed of fissile and compact till. This continuum is described for the first time.


Author(s):  
M. Iwatsuki ◽  
Y. Kokubo ◽  
Y. Harada ◽  
J. Lehman

In recent years, the electron microscope has been significantly improved in resolution and we can obtain routinely atomic-level high resolution images without any special skill. With this improvement, the structure analysis of organic materials has become one of the interesting targets in the biological and polymer crystal fields.Up to now, X-ray structure analysis has been mainly used for such materials. With this method, however, great effort and a long time are required for specimen preparation because of the need for larger crystals. This method can analyze average crystal structure but is insufficient for interpreting it on the atomic or molecular level. The electron microscopic method for organic materials has not only the advantage of specimen preparation but also the capability of providing various information from extremely small specimen regions, using strong interactions between electrons and the substance. On the other hand, however, this strong interaction has a big disadvantage in high radiation damage.


Author(s):  
M.A. Mogilevsky ◽  
L.S. Bushnev

Single crystals of Al were loaded by 15 to 40 GPa shock waves at 77 K with a pulse duration of 1.0 to 0.5 μs and a residual deformation of ∼1%. The analysis of deformation structure peculiarities allows the deformation history to be re-established.After a 20 to 40 GPa loading the dislocation density in the recovered samples was about 1010 cm-2. By measuring the thickness of the 40 GPa shock front in Al, a plastic deformation velocity of 1.07 x 108 s-1 is obtained, from where the moving dislocation density at the front is 7 x 1010 cm-2. A very small part of dislocations moves during the whole time of compression, i.e. a total dislocation density at the front must be in excess of this value by one or two orders. Consequently, due to extremely high stresses, at the front there exists a very unstable structure which is rearranged later with a noticeable decrease in dislocation density.


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