Triply periodical particulate matrix compositesinvarying external stress fields

1999 ◽  
Vol 36 (25) ◽  
pp. 3837-3859 ◽  
Author(s):  
V.A. Buryachenko
Keyword(s):  
External Stress ◽  
Stress Fields ◽  
Particulate Matrix

scholarly journals {\bb Z}-module defects in crystals

2017 ◽  
Vol 73 (6) ◽  
pp. 427-437 ◽  
Author(s):  
Abdullah Sirindil ◽  
Marianne Quiquandon ◽  
Denis Gratias
Keyword(s):  
Physical Space ◽  
External Stress ◽  
Unit Cell ◽  
Stress Fields ◽  
Acta Cryst ◽  
Burgers Vector ◽  
3 Dimensional ◽  
Linear Defects ◽  
Partial Dislocations ◽  
Zero Vector

An analysis is presented of the new types of defects that can appear in crystalline structures where the positions of the atoms and the unit cell belong to the same {\bb Z}-module,i.e.are irrational projections of anN> 3-dimensional (N-D) lattice Λ as in the case of quasicrystals. Beyond coherent irrationally oriented twins already discussed in a previous paper [Quiquandonet al.(2016).Acta Cryst.A72, 55–61], new two-dimensional translational defects are expected, the translation vectors of which, being projections of nodes of Λ, have irrational coordinates with respect to the unit-cell reference frame. Partial dislocations, called heremodule dislocations, are the linear defects bounding these translation faults. A specific case arises when the Burgers vectorBis the projection of a non-zero vector of Λ that is perpendicular to the physical space. This new kind of dislocation is called ascalar dislocationsince, because its Burgers vector in physical space is zero, it generates no displacement field and has no interaction with external stress fields and other dislocations.

scholarly journals Width Design of Small Coal Pillar of Gob-Side Entry Driving in Soft Rock Working Face and Its Application of Zaoquan Coal Mine

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Ai Chen
Keyword(s):  
Coal Mine ◽  
Coal Pillar ◽  
Soft Rock ◽  
External Stress ◽  
Stress Fields ◽  
Working Face ◽  
Roadway Stability ◽  
Calculation Results ◽  
Stress Zone ◽  
Internal Stress Field

Reasonable width of gob-side coal pillar can reduce the waste of coal resources and is conducive to roadway stability. According to the distribution of internal and external stress fields at the working face, a method for determining the width of gob-side coal pillar was proposed. The coal pillar and roadway should be set within the internal stress field, and support is provided through the anchored part and the intact part of the coal pillar. The method was used in the design of the coal pillar at No. 130205 working face of Zaoquan Coal Mine. The calculation results indicated that the width of a coal pillar suitable for gob-side entry is 6.0 m. It is reasonable to arrange the roadway and coal pillar in the low-stress zone with a width of 11 m. During tunnelling of roadway and stoping of the working face, the deformation of the roadway increased with a reduction in the distance from the working face. Even during stoping of the working face, there was an approximately 1.5 m intact zone in the coal pillar. This indicates that the proposed method of designing small coal pillar of gob-side entry driving is reliable.

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