PSI - Issue 72

Petro Gomon et al. / Procedia Structural Integrity 72 (2025) 294–300

297

 

   

0;

M N



(1)

, x arm

0;



, z arm

Equilibrium equations for determining the forces in the cross-section

0

    wc M M M M M M M N N N N N N             s c , plwt , s t , plwc wt , , ,

0



, wc

, wt

, s c

, s t

, plwc

, plwt

i

(2) Internal forces and moments arising in the normal section of a bending element with consideration of deformation functions of wood and reinforcement

u c wc f c ,

1

  с s c wc s u , , ,

  

(

)

wc N b y ,

u

du A f 

(3)

u

w c ,

c

0

u

t

1

  s t wt s t u , , ,

t    w t N b y f ,

(

)

u

du A f 

(4)

w t ,

w t ,

u

t

0

u

u

c

  s c с s c wc s u y , , , ,

0 

2

(5)

w c ,

u du A f ( ) ,  w c

wc M b y ,  

f

wc ,

c

2

u

c

u

t

u

  s t wt s t s t u y , , , ,

t    2

t wt 2 ,

u du A f ( ) ,  w t

wt M b y ,

f

.

(6)

wt ,

u

0

The magnitude of internal forces perceived by the metal reinforcement and the forces perceived by the plywood in the compressed and tensile zones will be equal to   с s c s c s s c N A f u , , , ,  (7)   s t s t s t s t N A f u , , , ,  (8)   с plwc plwc plwc plw f u N A , , , ,  (9)   plwt plwt plwt plwt f u N A , , , ,  (10)

The value of the bending element perceived by the reinforcement and plywood in the compressed and tensile zones will be equal to

s c s c s c M N y , , , 

(11)

s t s t s t M N y , , , 

(12)