The rotations calculated based on the displacement profiles typically exhibited the

same trends as the rotations recorded by the tilt meters.

 The tilt meter rotations were higher than the rotations calculated based on the

displacement profiles. That could be due to the fact that the tilt rotations were essentially

the rotations of the beam at the point the tilt meters were located whereas the calculated

rotations were based on a line that was fitted through several points along the entire

length of the beam.

 On the average the tilt meter rotations were approximately 24% higher than the

rotations calculated from the displacement profiles from the control beam (see Fig 4-20)

and approximately 10% for the tube beam (see Fig. 4-21). The rotations for the T2

location were graphically presented for both the control and tube beam and were used to

demonstrate the differences. These differences were typical for all four rotation locations.

Table 4-6. Rotations calculated based on the displacement profiles
Beam Load Rotation Rotation Rotation Rotation
 (kips) at TI at T2 at T3 at T4
 location location location location
 (degrees) (degrees) (degrees) (degrees)
 Control 21.9 -0.1027 -0.0909 -0.0858 -0.1530
 43.7 -0.2306 -0.2002 -0.1914 -0.2968
 65.6 -0.3425 -0.3193 -0.3094 -0.3991
 87.3 -0.4611 -0.4485 -0.4287 -0.5429
 109.0 -0.6073 0.6016 -0.5717 -0.7047
 148.0 -0.9282 -0.9626 -0.9110 -1.1150
 Tube 22.4 -0.0549 -0.0867 -0.0776 -0.1402
 45.4 -0.1728 -0.1966 -0.1814 -0.2667
 67.4 -0.2999 -0.3116 -0.2931 -0.4008
 89.2 -0.4202 -0.4388 -0.4147 -0.5301
 110.2 -0.5346 -0.5901 -0.5611 -0.6704
 152.3 -0.8938 -0.9798 -0.9397 -1.0600

 Based on the rotation data it can be concluded that the calculation of beam rotations

from the displacement profiles was valid. The fact that the two methods of determining