Alternative Support Systems for Cantilever - National Transportation ...

Figure 5-11. Widening of concrete breakout failure cracks in second test
5.2.2 Summary of LVDT Test Results
Data was reduced to formulate an applied load versus rotation plot for both flexure and
torsion. The plots show that the embedded pipe and plate configuration ceased taking on
additional load after 26.3 kips after the concrete breakout failure from flexure resulting from the
applied bending moment. The cylinder tests indicated that the compressive strength of concrete
on the day of testing was 5180 psi. When the predictions with the 28 day concrete strength were
made, the flexural concrete breakout was predicted to be 26.4 kips and the torsional concrete
breakout was predicted to be 37.5 kips. When the predictions with the 28 day concrete strength
were made, the flexural side-face blowout strength was predicted to be 40.9 kips and the
torsional side-face blowout strength was predicted to be 56.4 kips. The applied load versus
torsional plate rotation plot also shows a change in slope when the specimen experienced a
redistribution of load due to bolt slippage, bond changes, formation of various cracks, and
widening of cracks. See Figure 5-12for the graph of applied load versus torsional plate rotation.
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