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Acceleration loads are used to simulate the ground motion of a time-history acceleration record. Software

CSI software assumes complete fixity for all supports, then automatically computes acceleration loads at each node and structural object. Translational acceleration loads are taken as the negative product of the product of assembled joint mass and input acceleration.

At any point in a structure, translational acceleration is given by the cross product of the position vector (relative to the origin of rotation) and the acceleration vector. Resultant force is then the negative of the product of this translational - acceleration value and the translational mass. For example, RY acceleration would generate MY, FX, and FZ values.

For additional information, please see the the CSI Analysis Reference Manual (Acceleration Loads, page 304).

Rotational acceleration loads

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