Sentence 4.1.8.11.(9)

Intent 1:

To limit the probability that the calculation of loads due to earthquake will not take into account the forces due to expected seismic torsional moment at any level of the building, taking into account uncertainty in the determination of the centre of mass and centre of stiffness, inaccuracy in the measurement of the dimensions of structural elements, variations in material properties, or rotational ground motion, which could lead to:

• the excessive deformation of, or excessive stress in, the structural elements, which could lead to damage to the building, or
• the excessive deformation of, or excessive stress in, the building structure, which could lead to damage to the building, which could impede the intended use and occupancy of the building.

Intent 2:

To clarify that torsional effects are to be addressed concurrently with the static loads determined in Sentence 4.1.8.11.(7).

Intent 3:

To direct Code users to Sentence 4.1.8.11.(11) for the calculation of torsional loads.