Load and movement data from the loading head as well as data from the LVDTs

were collected using a data acquisition program at a rate of 50 Hz. This high rate was

necessary to capture the post peak behavior of the cylinders.



 6


 4s


 S2



 0 20 40 60 80
 Time (sec)

Figure 3-7. Typical load rate for control cylinders








 LVDT








 Lo.l





Figure 3-8. CFRP grid cylinder test set-up

 Cylinder Results and Discussion

 The average strength for the control cylinders tested in displacement control mode

was 6.83 ksi and the COV 1.1%. Results from the control cylinders can be found in Table