Design Code

Determine the design code and the special provisions for seismic design (if required) to perform the design or the strength verification for RC members.

From the Main Menu select Design > Concrete Design Parameter > Design Code

From the Menu tab of the Tree Menu select Design > Concrete Design Parameter > Design Code

The following dialog box is used to enter the data:

[When Eurocode2:04 is selected]

Design Code

RC design code (refer to Note 1)

National Annex

National Annex for Eurocode2:04.

Revision of Gen 2010

Apply Special Provisions for Seismic Design

Option to apply the capacity design rule as per EN1998-1:2004

Note. How to calculate design forces of capacity design as per EN1998-1:2004

Strut Angle for Shear Resistance

The angle between the concrete compression strut and the beam axis perpendicular to the shear force

Slenderness Limit

 (5.13N) in EN1992-1-1:2004

(Default value is '0.7'.)

 (Default value is '1.1'.)

(Default setting is 'Calculate by Program'.)

Apply NTC2008

Option to apply the capacity design rule as per NTC2008

Note. How to calculate design forces of capacity design as per NTC2008

Strong Column Weak Beam

Define the ratio to satisfy the ductility condition at all the joints. Default value is '1.3'.

 eq. (4.9) in EN1998-1:2004

Select Ductility Class

For EC8:04

DCH: High ductility level

DCM: Medium ductility level

For NTC2008

CD "A": High ductility level

CD "B": Medium ductility level

Shear Force for Design (Gamma_rd)

Define the factor accounting for possible overstrength due to steel strain hardening

Default value is as follows:

Secondary Seismic Element

Define the secondary seismic elements in order to preclude the capacity design rule

Friction Coefficient for Wall Sliding

Define the concrete-to-concrete friction coefficient under cyclic actions, which may be assumed equal to 0.6 for smooth interfaces and to 0.7 for rough ones. The default value is 0.7.

Structure Information

Structure Type: Define structure type to calculate behavior factor and determine the wall design method

Behavior Factor (q): Behavior factor to account for energy dissipation capacity shall be derived for each design direction as follows:

Calculate by Program: Behavior factor is automatically calculated and applied to the capacity design.

Alpha u / Alpha 1: The multiplication factor for buildings which are regular in plan.

User Input: Behavior factor is directly entered by the user.

Note. Behavior factor for horizontal seismic actions

Elastic Response Spectrum

Default By Function: Select response spectrum function defined in Response Spectrum Function. The spectrums of 'Eurocode8' and 'User Type' are available.  

Spectrum Parameters

Soil Factor (S)

Tb: The lower limit of the period of the constant spectral acceleration branch

Tc : The upper limit of the period of the constant spectral acceleration branch

Td: The value defining the beginning of the constant displacement response range of the spectrum

Ref. Reak Ground Acc. (AgR): The design ground acceleration on type A ground

Importance Factor (I)

Viscous Damping Ratio (xi)

[When ACI318-05 is selected]

Concrete Design Code dialog box

Design Code

RC design code (refer to Note 1)

Apply Special Provisions for Seismic Design

Option to apply the special provisions for seismic design

 : Enter the selection and close the dialog box.

 : Do not enter the selection and close the dialog box.

Select Frame Type

Apply different Scale up Factor for Shear for each seismic zone (This is applicable for ACI318-89, 95, 99, 02,05).

Special Moment Frames: Moment frame in strong-motion seismic zone

Intermediate Moment Frames: Moment frame in intermediate-motion seismic zone

Ordinary Moment Frames: Moment frame in weak-motion seismic zone

Shear for Design

Apply Scale up Factor for Shear as per special provisions for seismic design.

: Apply Scale up Factor for Shear as per a relevant code.

R*Vc(a1*SUM(Mpr)/L>max(Ve1,Ve2)/2)     

R: ACI318-05 Clause 21.3.4.2 indicates that " Transverse reinforcement shall be proportioned to resist shear assuming Vc=o when ...". In midas, even though such conditions occur, the user can include a part of shear strength of concrete as well as shear reinforcement.

Method: Select a method to apply Scale up Factor for Shear.

Max(Ve1, Ve2): Use the larger of the shear forces to which Scale up Factors for Shear (a1, a2) will have been applied.

Min(Ve 1, Ve 2): Use the lesser of the shear forces to which Scale up Factors for Shear (a1, a2) will have been applied.

Ve 1: Select to apply Scale up Factor for Shear (a1).

Ve 2: Select to apply Scale up Factor for Shear (a2).

Revision of Gen 2012

[When TWN-USD100 is selected]

Apply Special Provision for Seismic Design

Option to apply the special provision for seismic design.

Shear for Design

Apply Scale up Factor for Shear as per special provisions for seismic design.

: Apply Scale up Factor for Shear as per a relevant code.

R*Vc(a1*SUM(Mpr)/L>max(Ve1,Ve2)/2)     

R: ACI318-05 Clause 21.3.4.2 indicates that " Transverse reinforcement shall be proportioned to resist shear assuming Vc=o when ...". In midas, even though such conditions occur, the user can include a part of shear strength of concrete as well as shear reinforcement.

Method: Select a method to apply Scale up Factor for Shear.

Max(Ve1, Ve2): Use the larger of the shear forces to which Scale up Factors for Shear (a1, a2) will have been applied.

Min(Ve 1, Ve 2): Use the lesser of the shear forces to which Scale up Factors for Shear (a1, a2) will have been applied.

Ve 1: Select to apply Scale up Factor for Shear (a1).

Ve 2: Select to apply Scale up Factor for Shear (a2).

Revision of Gen 2011

SCWB Design/Checking Method

Option for design force calculation  special provision for seismic design.

Design Strength: Perform strong column-weak beam design and checking using the design strength of beams ( ).

[Ductile Design & Checking calculation]

[Strong Column Weak Beam Ratio Calculation]

Nominal Strength: Perform strong column-weak beam design and checking using the nominal strength of beams ( ).

[Ductile Design & Checking calculation]

[Strong Column Weak Beam Ratio Calculation]

Torsion Design

Apply torsional design based on Taiwanese Concrete Design Code clause 4.7. This option is applicable for TWN-USD92 only.

Note 1

If the user omits the design code, the Concrete Structure Design Code of the European Standard (Eurocode2:04) is applied by default. Available RC design codes are as follows:

- EN 1992-1-1:1994 Eurocode2, Design of concrete structures Part 1 (Eurocode2:04)

- ENV 1992-1-1:1992 Eurocode2, Design of concrete structures Part 1 (Eurocode2)

- Ultimate Strength Design, the American Concrete Institute (ACI318-05/02/99/95/89)

- Canadian Standards Association of Concrete Structures (CSA-A23.3-94)

- British Standard, Structural use of concrete Part 1 (BS8110-97)

(available upon request)

- Taiwan (TWN-USD10)

- Indian Standard (IS456:2000)

- China Standard (GB50010-02)

- Architectural Institute of Japan (AIJ-WSD99)

- Architectural Institute of Korea (AIK-USD94)

- Korean Society of Civil Engineers (KSCE-USD96)

- Korean Concrete Institute (KCI-USD99)

- Architectural Institute of Korea (AIK-WSD2K)