The strip forces are the integration of element forces (reported in force per unit width) along the strip width. SAFE reports the integration of force immediately before and after a design station. For example, refer the one element model shown in Figure 1 for which the element forces are are tabulated in Figure 2.
Figure 1: Element and joint numbering
Figure 2: Element forces
The element length is 1 m (distance between point 1 and ~5) and width is 0.5 m (distance between ~5 and ~9). The points with "~" sign refers to internal points created due to auto area meshing.
Integration of area forces along the width of element (i.e. 0.5 m) yields the following:
Strip Moment immediately After point 1 and ~8 = Average forces between points 1 and ~8 * strip width =(0.0386 kN-m/m+1.3514 kN-m/m)/2*(0.5m) = 0.3475 kN-m
Strip Moment immediately Before point ~5 and ~9 = Average forces between points 1 and ~8 * strip width = (0.4171 kN-m/m + 0.8889 kN-m/m)/2*(0.5m) = 0.3265 kN-m
You can also refer to the attached Excel file and the SAFE model where strip force integration is shown for the full model containing element 1 shown in Figure 1. There is a slight difference in strip forces computed in Excel vs. reported by SAFE due to significant digit.
