User Guide

Project Prerequisites

The floor vibration check in SCIA Engineer is available when 1) the ‘code’ setting in the project is set to ‘IBC’ 2) the ‘structure’ setting in the project is set to ‘General XYZ’ and 3) concrete and steel materials are active. To run the check, results must exist in the project (i.e. the calculation must be run).

Floor Vibration Setup and Floor Vibration Beam Data

Settings related to how the floor vibration check is implemented in the project can be input in two ways: as floor vibration setup data or as floor vibration beam data. Floor vibration setup inputs are applied to the entire project while floor vibration beam data inputs are applied only to the members to which beam (or member) data is applied. For inputs which are available in both the floor vibration setup and in the floor vibration beam data, the input in the beam data will override the input in the setup.

Floor Vibration Setup Options:

Damping coefficient	Damping coefficient or damping ratio. Default is 0.03. See Table 4-2 of Design Guide 11 for information on how this value can be calculated based on building components.
Occupancy	Occupancy type of building. This setting is used to determine the values used for acceleration tolerance limit and live load.
Override tolerance limit	Option to override the default acceleration tolerance limit.
Tolerance limit value	Acceleration tolerance limit (ao/g). Default values are based on occupancy type as follows: 1.5% for Shopping Malls and 0.5% for all others.
Override live load value	Option to override the default live load value.
Live load value	Live load value used in calculation of floor vibration. Default values are based on occupancy type as follows: 11 psf for Paper office, 6 psf for Electronic office and Residence, 0 psf for Assembly area and shopping mall.
Override dead load value	Option to override the default dead load value.
Dead load value	Dead load value used in calculation of floor vibration. Default is 4 psf.
Define floor length	Option to define and use a floor length in the calculation.
Floor length	Floor length value used in the calculation of the effective width for the girder panel mode. Floor length is defined in Design Guide 11 as ‘the distance perpendicular to the span of the girders in the bay under consideration over which the structural framing is identical or nearly identical in adjacent bays.'
Define floor width	Option to define and use a floor width in the calculation.
Floor width	Floor width value used in the calculation of the effective width for the joist panel mode. Floor width is defined in Design Guide 11 as ‘the distance perpendicular to the joist or girder span of the beams or joists in the bay under consideration over which the structural framing (beam or joist and girder size, spacing, length, etc.) is identical or nearly identical in adjacent bays.’

Floor Vibration Beam Data Options:

Floor vibration beam data includes all fields which are found in the setup with the exception of Occupancy Type* and with the addition of the following:

Panel position	Option to define a member as parallel to and at a free edge. If member is parallel to a free edge and part of an exterior bay, this setting should be set to ‘Exterior’. When set to ‘Exterior’ the member will receive a ‘Cj coefficient’ value of 1.0, otherwise it will receive a ‘Cj coefficient’ value of 2.0.
Do not consider member as continuous	Option to not consider member as continuous and therefore not increase the effective panel weight by 50%. By default, members are considered continuous and the effective panel weight is increased by 50%.

*Note : Although Occupancy Type cannot be set in member data, if a project consists of a multi-occupancy structure, the live load values and tolerance limits can be manually set as needed in the member data.

Running Check

Once any desired settings have been made in the setup and/or member data, the results of the check can be displayed by selecting Floor Vibration Check and then selecting Refresh in the properties window. A result value and selection can be set as needed. Note that the selection option only determines for which members the results are shown. By the nature of this check, all members in the project must be processed in the calculation. Additionally, it should be noted that no load case or combination is needed for the floor vibration check. Dead and live loads are simply defined in the setup or member data. The live load is based on the occupancy type by default and a dead load value of 4 psf is used by default.

Output and Results

Final results (such as the Acceleration relative to gravity and Unity check) as well as the intermediate result values can then be viewed in the Engineering Report Preview by clicking Preview or viewed in a table layout by clicking Table Results.

Wj	Beam effective panel weight (for the member under consideration)
Bj	Beam effective panel width (for the member under consideration)
Wg	Girder effective panel weight (for the girder supporting the beam if the beam under consideration is secondary)
Bg	Girder effective panel width (for the girder supporting the beam if the beam under consideration is secondary)
Beta	Damping Ratio (Used for the input but also shown as part of the output for reference)
W	Effective weight supported by the beam panel, girder panel, or combined panel, as applicable
fn	Natural frequency
ap/g	Acceleration relative to gravity
ao/g	Allowable acceleration relative to gravity
UC	Unity Check (Acceleration relative to gravity/ Allowable acceleration relative to gravity)