cracking moment was approximately 1.7 k-ft which was much lower than the moment

due to their self weight which was approximately 15 k-ft. The load-displacement of

specimen SCC1 was linear to failure with no signs of an initial higher stiffness because

the pile was already cracked. However, the load-displacement curves of specimens SCC2

and SCC3 had two stages. The first stage was between 0 and 1 kip in which the initial

stiffness degraded in a nonlinear way (Fig 6-25). The second stage was linear up to

failure. The initial non linear portion of the curve was due to the carbon wrap effect that

was applied to the specimens. The carbon wrap for specimens SCC2 and SCC3 extended

to the load points which was not the case for specimen SCC1. That was the reason the

initial nonlinear portion was not observed for specimen SCC1.

 15

 12 _





 3 -- SCC3 -
 -6r


 0 j
 0 3 6 9 12 15 18
 Displacement (in)

Figure 6-25. Load-displacement curves for piles SCC1, SCC2 and SCC3

 Specimens SCG1 and SCG3 were cracked due their weight. The cracking and self

weight moment of specimens SCG1 and SCG2 was approximately the same as for the

control specimens (SCC1, SCC2 and SCC3). The load-displacement curve of specimen

SCG1 was linear up to peak load. At peak load a small reduction in the capacity was

noted. Specimen SCG1 maintained load for a very short period after peak then lost all

load carrying capacity (see Fig 6-26). The load-displacement curve of specimens SCG3