From the evaluation of stress distribution within the front crossbar as shown (2.1), the association between the bending moment to stress perpendicular to the beam, cut according to the following equation:
Based on the results of the stress distribution within the beam cross section (Figure 2.1), the relationship between the bending stress in the cross section perpendicular to the beam according to the following equation.
Considering the effects of stress distribution in the cross-section beams, as shown in the picture (2.1) makes the หว่างโม apartment in relation with bending stress perpendicular to the shear beam according to the following equations