RPA99-2003 Seism family

 

The RPA99-2003 Seism family is created when the Algerian seismic standard RPA99-2003 is selected for the current project.

RPA99-2003 Seism loads family - Properties

Family

• Name: the default name of the family.

• No.: displays the ID number of the family.

• Spectrum: allows the selection of the spectrum type: RPA99-2003 spectrum or Imposed.

Note

By default, the spectrum corresponds to the current seismic standard, RPA99-2003. To view the standard spectrum: in the seism properties window, Spectrum category > Horizontal spectrum / Vertical spectrum, click . Also, it is possible to define a custom seismic spectrum using the Function editor.

Implantation

• Region: allows the definition of the construction zone: I, IIa, IIb or III, according to the classification from RPA 99/2003, chapter III, paragraph 3.1. The button displays the construction zones map and allows the selection of the corresponding zone.

Regions for RPA99-2003 seism loads family

• Site: allows the selection of the site type (i.e., S1, S2, S3, S4, according to the classification from RPA 99/2003, chapter III, paragraph 3.3.1, S5 or Envelope). For the "S5" value, the site coefficient ("S" field) has to be determined by a specialist.

• Importance category: allows the selection of the building's importance category, depending on the seismic hazard conditions and on public safety considerations.

• Behavior factor R: allows the user to enter the global behavior coefficient of the structure (according to RPA 99/2003, chapter IV, paragraph 4.2.3, table 4.3).

• Quality factor Q: the quality factor of the structure depends on:

- the redundancy and the geometry of the constituent elements;

- the regularity in plan and in elevation;

- the quality of the control of construction.

It is calculated with the formula 4-4, according to RPA 99/2003, chapter IV:

Spectrum

• Vertical Direction Coef.: allows the modification of the imposed vertical spectrum.

• Damping correction: by default, the program calculates the damping correction of the RPA99-2003 spectrum. When disabled, the damping correction is not applied. According to RPA 99/2003, chapter 4.2.3, the damping correction formula (4.3) is:

• Horizontal spectrum: the button provides access to the Function editor dialog box, where the horizontal spectrum parameters can be viewed or defined.

• Vertical spectrum: the button provides access to the Function editor dialog box, where the vertical spectrum parameters can be viewed or defined.

Note

To edit the spectrum parameters, the imposed spectrum option must be enabled: in the Family category, from the Spectrum drop-down list, select Imposed.

Mode superposition

• Method: allows the selection of the mode superposition method (i.e., CQC or SRSS).

• Residual mode: enables / disables the residual mode.

Combinations

Define properties that are taken into account when generating concomitance combinations. See Configuring load cases combinations.

• Group loads: when enabled, each load case inherits "combinations" properties from the corresponding load case family and will be grouped as a generic load case in the concomitance matrix.

• Effect: sets the load case as "Leading", "Accompanying" or both.

• Coefficient γ EQU: partial factor for seismic action considered in the EQU ultimate limit state

• Coefficient γ STR/GEO: partial factor for seismic action considered in the STR/GEO ultimate limit stat

• Ψ0 coefficient: factor that defines the combination value of a variable action

• Ψ1 coefficient: factor that defines the frequent value of a variable action

• Ψ2 coefficient: factor that defines the quasi-permanent value of a variable action

Color

• View / change the representative color for the family.

Tip

Click a section of the properties window. Notice the bottom area of the window; it displays a short description of the active cell's content.

Accessing the properties

After creating a seism family: in the Project Browser, expand the Loading group and select Seism RPA99-2003.