Figure 6 - Strains, Forces, and Moment Arms (Pure Moment)
This corresponds to the case where the factored axial load resistance, Pr, is equal to zero. Iterative procedure is used to determine the factored moment resistance as follows:
5.1. c, a, and strains in the reinforcement
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Where c is depth of the neutral axis measured from the compression edge of the column section. | CSA A23.3-19 (3.2) |
| CSA A23.3-19 (10.1.7) |
Where: | |
| CSA A23.3-19 (Equation 10.2) |
| CSA A23.3-19 (10.1.3) |
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| CSA A23.3-19 (8.4.2) |
| CSA A23.3-19 (8.4.3(a)) |
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5.2. Forces in the concrete and steel
| CSA A23.3-19 (10.1.7) |
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The area of the reinforcement in this layer has been included in the area (ab) used to compute Crc. As a result, it is necessary to subtract α1ϕcfc’ from ϕsfs’ before computing Crs: | |
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The assumption that c = 78.56 mm is correct | |
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