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3F<br />

⎛<br />

z ⎛ a−<br />

x⎞<br />

p( x)= 1−⎜<br />

⎟<br />

8ba<br />

⎜<br />

⎝ ⎝ a ⎠<br />

2<br />

⎞ Fz<br />

x a x<br />

⎟ = 3<br />

( ( 2<br />

⎠ ba<br />

− ))<br />

3 . (5.79)<br />

8<br />

Įveskime skersinio standumo į ploto vienetą koeficientą k ya<br />

N/m 3 :<br />

ky<br />

kya<br />

= . (5.80)<br />

2 b<br />

Tada galioja ryšis:<br />

( ) = ( )<br />

kya γ x µ p x<br />

slydimas<br />

z<br />

,<br />

3Fz<br />

kyaγ( x) = ( x( 2a−x<br />

slydimas<br />

)), (5.81)<br />

3<br />

8ba<br />

θ = 4 2<br />

ba kya<br />

1<br />

; γ( x) = ( x( 2 a−x<br />

slydimas<br />

)).<br />

3µ F<br />

2aθ<br />

Taške x s prasideda slydimas<br />

1<br />

γ( xs)= sxs = ( xs( 2 a−<br />

xs)<br />

);<br />

2aθ<br />

x 2 a 1−θ<br />

s . (5.82)<br />

s =<br />

( )<br />

Slydimo sritis yra xs < x ≤2 a .<br />

Skersridės jėga lygi:<br />

( )<br />

xs<br />

γ x<br />

2a<br />

s<br />

kya<br />

Fy<br />

= 2b∫<br />

kya<br />

x dx + 2b<br />

∫<br />

x<br />

a x 2 a −<br />

2 θ<br />

x dx<br />

8bk<br />

ya<br />

a<br />

6aθ<br />

0<br />

s<br />

⎛ xs<br />

1− ⎛ ⎝ ⎜<br />

⎞<br />

⎜ 2a<br />

⎟<br />

⎝ ⎠<br />

xs<br />

⎞<br />

x<br />

s<br />

µ Fz<br />

1<br />

⎟ = ⎛<br />

−⎛ 2a<br />

⎠ ⎝ ⎜ ⎞ ⎞<br />

⎟<br />

⎜<br />

⎝ ⎠ ⎟ ,<br />

⎠<br />

3 3 3<br />

bet x 2a 1 − sθ , tada skersridės jėga lygi:<br />

s =<br />

190<br />

( ) =<br />

F = µ F 1− 1−<br />

sθ<br />

3 . (5.83)<br />

y<br />

( )<br />

z( ( ) )

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