Strip force integration
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.