Calculated results for 2D members

Internal forces

Principal moments – plate

Label

Description

Calculation

m1

Principal moment (max)

m2

Principal moment (min)

alfa (bending)

Angle of principal moment m1

mtmax

Maximum torque moment

qmax (bending)

Maximum shear force perpendicular to the plane

beta

Angle of maximum shear force

Principal forces – wall

Label

Description

Calculation

n1

Principal force

(max)

n2

Principal force

(min)

alfa (membrane)

Angle of principal force n1

qmax (membrane)

Maximum shear force in the plane

Design moments from EC2 – plate

Label

Description

Calculation

mxD+

Design moment in x-direction on positive surface

 

 

myD+

Design moment in y-direction on positive surface

mcD+

Design moment in the concrete on positive surface

mxD-

Design moment in x-direction on negative surface

myD-

Design moment in y-direction on negative face

mcD-

Design moment in the concrete on negative face

Upper and lower surface of 2D member is determined by the Z axis direction of local coordinate system (LCS). Upper surface is in the positive direction of the Z axis and on the other hand Lower surface is in negative direction of Z axis. Upper surface values are marked with + and lower values are marked with -.

Design moments, classical method – plate

Label

Description

Calculation

mxD+

 

Design moment in x-direction on positive face

myD+

Design moment in y-direction on positive face

mcD+

Design moment in the concrete on positive face

mxD-

Design moment in x-direction on negative face

myD-

Design moment in y-direction on negative face

mcD-

Design moment in the concrete on negative face

Design forces from EC2 – wall

Label

Description

Calculation

nxD

Design force in x-direction

nyD

Design force in y-direction

ncD

Design force in the concrete

Design forces, classical method – wall

Label

Description

Calculation

nxD

Design force in x-direction

nyD

Design force in y-direction

ncD

Design force in the concrete

The calculation of the design forces for the plates and shells according to the EC2 algorithm uses the flow diagram in ČSN P ENV 1992–1–1 (731201), Appendix 2, par. A2.8. Following rules are valid for the indices:

The calculation of the design forces for the walls and shells according to EC2 algorithm uses the flow diagram in ČSN P ENV 1992–1–1 (731201), Appendix 2, par. A2.9. Following rules are valid for the indices:

Magnitudes mxD and myD (or nxD and nyD) are the design moments (or forces) in the reinforcement. The negative values of the moments or forces have no practical meaning and they are featured only by reason of integrity.

Magnitude mcD (or ncD) is design moment (or force) in the concrete and together with design moments (or forces) in the reinforcement it forms unity triplet with respect to invariant:

The design force in the concrete ncD is used at concrete crushing check (see ČSN P ENV 1992–1–1 (731201), Appendix 2, par. A2.9). The design moments in the concrete mcD are not mentioned in this code, but their meaning is analogical and they are stated by reason of integrity.

The values of the design moments and forces according to „classical“ algorithm are calculated according to the left branches of the flow diagrams stated above, i.e. without respect to the relation between mx, my and mxy (or nx, ny a nxy). This calculation is on the safe side, but in some cases it could be less optimal.

The right branch is used if some of the directions of the reinforcement calculated according to the left branch is pressed (negative value of the correspondent design magnitude). In this case a zero value of the design magnitude is assigned to this direction, and the other direction will have lower value of design magnitude (and consequently lower necessary reinforcement area) than by calculation according to the left branch (the condition of the capacity is granted in both cases). The calculation according to the right branch causes higher pressure in the concrete (magnitudes mcD and ncD) than according to the left banch. By this point of view the EC2 algorithm could be considered as more cost-effective.

 2. Stresses, group=3

Basic stresses on 2D

Label

Description

Calculation

sigxb (not disp.)

Stress by bending moments

sigyb (not disp.)

Stress by bending moments

sigxyb (not disp.)

Stress by bending moments

sigxm (not disp.)

Stress by normal forces

sigym (not disp.)

Stress by normal forces

sigxym (not disp.)

Stress by normal forces

sigx+

Stress on positive face

sigy+

Stress on positive face

sigxy+

Stress on positive face

sigx-

Stress on negative face

sigy-

Stress on negative face

sigxy-

Stress on negative face

tauxz (not disp.)

Shear stress perpendicular to the plane

tauyz (not disp.)

Shear stress perpendicular to the plane

Principal stresses on 2D

Label

Description

Calculation

sig1+

Principal stress on positive face (max)

sig2+

Principal stress on positive face (min)

alfa+

Angle of principal stress sig1+

sigE+

Equivalent stress on positive face (Mises)

sig1-

Principal stress on negative face (max)

sig2-

Principal stress on negative face (min)

alfa-

Angle of principal stress sig1-

sigE-

Equivalent stress on negative face (Mises)

taumaxb

Maximum shear stress perpendicular to the plane

sigZ

Stress for plane stress

sigEmax

Maximum equivalent stress (Mises)

sigmE

Membrane equivalent stress (Mises)

sigm1

Principal membrane stress on positive face (max)

sigm2

Principal membrane  stress on positive face (min)

alfam

Angle of principal membrane stress sig1m

Stresses on 3D

Label

Description

Calculation

sig1, sig2, sig3

Principal stresses

Eigenvalues of stress matrixσ

taumaxB

Maximum shear stress

sigEM

Equivalent stress (Mises)

Strains, group=14, Plastic strains, group=15

Strains on 2D

Basic strains are calculated using following formula:

a)     Bending strains

;  ; ;

b)    Shear strains

 ;  ;  ;

c)     Membrane strains

 ;  ;  ;

Label

Description

Calculation

epsx+

Strain on positive surface

epsy+

Strain on positive surface

gamaxy+

Slope on positive surface

epsx-

Strain on negative surface

epsy-

Strain on negative surface

gamaxy-

Slope on negative surface

eps1+

Principal strain on positive surface (max)

eps2+

Principal strain on negative surface (min)

alfa+

Angle of principal strain on positive surface

eps1-

Principal strain on negative surface (max)

eps2-

Principal strain on negative surface (min)

alfa-

Angle of principal strain on negative surface

epsM+

Equivalent strain on positive surface (Mises)

epsM-

Equivalent strain on negative surface (Mises)

epsM

Maximum equivalent strain (Mises)

Strains on 3D

Label

Description

Calculation

eps1, eps2, eps3

Principal strains

Eigenvalues of strain matrixε

epsM

Equivalent strain (Mises)

R1, R2, R3 are the eigenvalues of the matrix R: