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You have the following options for determining the relative rigidity of shear walls for torsional analysis:
Use shear wall deflection the calculate rigidity (recommended)
Using this method, the program uses the sum of segment stiffnesses on the line, or S F/D, to calculate rigidity, where F is the force on the segment and D is the deflection calculated for that segment. When deflections are equalised on the line (see below), this is just F/D, where F is the shear line force and D is the common deflection. Using this method, the rigidities appear as force / displacement (kN/mm, lbs/in, or kips/in) in the Torsional Analysis Details output, that is, the rigidity expressed as force per unit deflection.
Use shear wall capacity to approximate rigidity
With this method, the program uses the shear wall rigid diaphragm analysis found from the Flexible Design Method to approximate the relative rigidities. This method is considered by SEAOC and other design code authorities to be an acceptable alternative to more rigorous rigidity analysis that takes into account framing bending, sheathing shear stiffness, and nail and hold-down slippage.
Using this method, the rigidities appear as force units (kN, lbs, or kips) in the Torsional Analysis Details output, that is, the rigidity expressed as force/length multiplied by the shear wall length.
Manually assign the relative rigidities
With this method, you can enter any number using any criterion for relative shear wall rigidity, keeping in mind it is only the ratio of these numbers for the various shear lines that matters. The default that first appears is 1.0, so that the to the shear walls have equal rigidity. If you change from the capacity method, the number that appears is the capacity in lns/in. If you change from the deflection method, the number that appears is the sfiffness in lbs/in. .
Using this method, the rigidities appear as dimensionless numbers in the Torsional Analysis details output.
Note that It is possible to first use the shear wall capacity or deflection option, and then adjust rigidities using the manual method.