This page is devoted to frequently asked questions (FAQ) related to acceleration.
Acceleration-load calculation
Question: How does SAP2000 calculate and apply acceleration load?
Answer: Please see the [Acceleration load] article for response.
Rotational-acceleration-load calculation
Question: What procedure does
CSI
Software use to calculate rotational-acceleration load?
Answer: Please see the [Acceleration load] article for response.
Difference between relative and absolute acceleration
Question: The Display > Show Plot Functions menu presents options for either relative or absolute acceleration. What is the difference between these options?
Answer: Relative acceleration is within the reference frame of the structure. Absolute acceleration is within a universal reference frame, and given as the sum of relative acceleration and ground acceleration.
The same relative and absolute designations also apply to velocity and displacement.
Manual application of acceleration load
Question: Can acceleration loads only be applied to selected members in a model?
Answer:
CSI
Software automatically generates and envelopes a set of acceleration loads for translation along, and rotation about, each global axis. These acceleration loads are applied at each node and element, and used to simulate ground motion during time-history and translation-only response-spectrum analyses. They are also useful as starting load vectors for Ritz-vector analysis.
Users may manually assign acceleration loads to specific nodes and elements. Similar to load-case assignment, these loads are applied through an analysis case.