Design and Stress Analysis of Extraterrestrial ... - The Black Vault

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(a) Fig. 1,31., Uniaxial (a) and
two-dimensional (b) stressed
state of a sample.
(b)
Strict analysis indicates that the diagram of deformation
for a sample in a uniaxial stressed.state., according to law a =E
can be used for determining the supporting power of an element in
a two-dimensional or three-dimensional stressed state if, instead
of ax and ex or ay And wyWe compare generalized or equivalent
,stress a., which is called intensity of stresses, and generalized or
-equivalent deformations ci, obtained in accordance with one of the
theories of material strengths. Then the basic relationship between
stress and deformation will have the form
where
a =ESt is(1,26)
Equivalent stress a,, i.e., stress which should.ýbe created
in 'an extended sample;so that its stressed state correspond to a
given state,, is most. frequently in accordance with.one of two
strerýth theor`tes,. the theory based on equality of the largest
tangential stresses and the theory of the equalityof distortion
enorgy. The first-is widely used in tasks, where the limiting
stage is characterized by a transition of the elastic state to
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