PSI - Issue 36

Vasyl Romashko et al. / Procedia Structural Integrity 36 (2022) 269–276 Vasyl Romashko, Olena Romashko-Maistruk / Structural Integrity Procedia 00 (2021) 000 – 000

273

5

   

   

M r

M M

r D

r D

= 2 1 1/ r

2

u l

o

u

u l

o

(1

)

+ − − ((1 2

)

 M M M 2 ) 4 −

l M M M

(6)

,

−

+

l

l

u

u

f

u

u

l M is the bending moment from the operating load action.

where

M

(a)

M u

M u

2W

2W

l

l

M

M

2W 1

2W 3 l

2W 2

2W 1

2W 2

2W 3

l

l

l

l

l

M cr

1/ r wl

1/ r cr

1/ r w

1/ r 1/ r f ul

1/ r wul

1/ r f

1/ r f l

1/ r 1/ r u

1/ r u

w

f

w l w u w ul

f l

f u f ul

w,f

 c f ck

(b)

 cl

 sf

 sul

 su

 c

E cu

 sf l

 s

 cf

 cf l

 cu

 cul

f yk  s

Fig. 1. To the calculation of reinforced concrete elements resource according to the energy criterion: the type of element state diagrams and the potential energy of its deformation (a); type of reinforcement and concrete deformation diagrams under different loading conditions (b).

The main difference of the deformation-force model in comparison with others is that with the help of the above mentioned force and deformation characteristics ( M and r 1 / ) it is possible not only to control the change in the reinforced concrete elements stiffness characteristics, but also to estimate the potential energy of their deformation. For this, in the deformation-force model, a hypothesis of the invariability of the potential destruction energy of the