1997). The lower value of the strain was due to the fact that the gages were located at

mid-span and concrete crushing took place at the south load location.

 For pile SCC2 the top compressive strain at peak load at mid span was

approximately 2360 ,s (see Fig. 6-36). However the strain recorded at the south load

location was higher, approximately 2665 aE. The strain gages at the south load were not

located on the top of the specimen. Therefore it was logical to assume that the strain on

the top of the specimen at the south load location was higher and probably close to 3000

,E. The higher strain at the south load location indicated that concrete crushing was

taking place there which verified the observations made during testing.

 15



 '-9



 -e- S1(SCG1)
 -8- S2 (SCG1)


 0 500 1000 1500 2000 2500 3000 3500
 Top Concrete Strain (microstrains)

Figure 6-35. Compression zone load-strain curves for specimens SCC1 and SCG1

 The maximum compressive strain recorded for specimen SCC3 at peak load was

2810 ,s while for specimen SCG3 was 2600 ,s (see Fig. 6-37). The maximum strain

recorded for specimen SCC3 was higher than the maximum strain recorded for specimen

SCG3 but that was attributed to the effect of the CFRP grid that restrained concrete

movement and to the higher concrete strength of specimen SCG3 compared to specimen

SCC3. Higher strength concrete tends to have lower crushing strains (Nawy 2005;

Hasoun and Al-Manaseer 2005; Hassoun 2002; MacGregor 1997).