When replacing the stress out of the equation (2.4). Into the equation (2.5). It is possible to write the relation of moment and curvature. According to the following equation:
When the stress from the equation (2.4) into the equation (2.5) can be written in the moment, and the relationship of the arc. According to the following equation.
When, instead of stress from equations (2.4) into the equation (2.5). You can write the relationship of moment and curvature. According to the following equation