Footfall analysis coefficients

The Footfall Analysis functionality is available if the Vibration analysis functionality is activated in the project. This type of analysis enables the evaluation of vibration response of floors or structures induced by walking persons.

This functionality requires the definition of input parameters related to walking-induced dynamic loads, such as amplitude coefficients and phase angles (for further information see Footfall analysis background). These parameters are managed via the Footfall Analysis Coefficients library, which is explained in the following sections.

Footfall coefficients

The Footfall Coefficients dialog opens automatically if no coefficient set has been defined yet or manually via the "New" or "Edit" options in the library.

Within this dialog, you can define the following:

Once the Design Method, Activity, and Source are selected, the software automatically fills the table below these settings with default harmonic coefficients and phase angles recommended by the selected standard. The detailed types of activities and sources for each standard are described on separate HELP pages (click on the standards above).

The table contains the following columns:

  1. Number of harmonic term

  2. Amplitude coefficient - αh

  3. Phase angle - Φh

In addition to the standard values, the table can be manually edited if Source is set to "Manual input". In this case, the user can modify the amplitude coefficients and phase angles directly.

However, it is never possible to change the number of harmonic terms for a given activity. For example, if SCI P354 specifies 4 harmonic terms for the walking activity, only the coefficients and phase angles for these 4 harmonics can be edited manually.

Footfall analysis coefficients

The Footfall Analysis Coefficients library stores all the coefficient sets that are created within the project. This library provides a centralized place where users can create new sets, edit existing ones, duplicate them for further adjustments, or delete those that are no longer needed.

Working with this library follows the same principles as managing any other libraries available in SCIA Engineer. This makes the process familiar and intuitive for users who have experience with other library types.

The parameters and settings accessible in the library are exactly the same as those defined in the Footfall Coefficients dialog. This ensures that there is no difference between the way coefficients are created and the way they are later managed. Any modification made in the library is automatically applied wherever the corresponding coefficient set is used in the project.

Units

The display format for both amplitude coefficients and phase angles used in footfall analysis can be adjusted in the Units settings, located under the Dynamics section.