beam rotations yielded comparable results makes both methods acceptable. Therefore,

determining the curvature of the beams using the displacement profiles was also validated

based on the rotation results. If rotation results were valid then curvature results were also

valid because the same basic equations were used to determine both.

 160
 140
 120
 S100
 80
 60 3
 T2-Tilt 40
 -- T2-Displ.
 20


 -1.5 -1.2 -0.9 -0.6 -0.3 0.0
 Rotation (degrees)


Figure 4-20. Measured rotations at increasing loads (control beam)


 160
 140
 120 ,
 100
 80
 60 -g
 60

 -A-T2-Tilt I 40
 -B- T2-Displ. 20

 0
 -1.5 -1.2 -0.9 -0.6 -0.3 0.0
 Rotation (Degrees)


Figure 4-21. Measured rotations at increasing loads (tube beam)

 Moment-Curvature Analysis

 The LVDT measurements, at different locations along the length of the beams,

were used to construct the displacement profile curves (see Fig. 4-22) at increasing loads.

The displacement profile equation was generated by fitting a sixth order polynomial line