(a) (D)

Figure 3-4. CFRP strand tests: (a) CFRP grid strand specimen and (b) test set-up

 Table 3-2 shows the results of the tensile tests. Strands taken from the longitudinal

direction are designated longitudinal (L) and strands taken from the transverse direction

are designated transverse (T). All the specimens ruptured at peak load. Three specimens

ruptured away from the anchor and only one close to the anchor. All specimens ruptured

at an interception of a longitudinal and a transverse strand. The average peak load per

strand was approximately 951 lbf and was approximately 16% lower than the load

provided by the manufacturer which was 1100 lbf (TechFab 2004). The average cross

sectional area was approximately 0.097 in2. The average strength was approximately

100.8 ksi and the average tensile modulus 9235 ksi. The strength of each specimen was

calculated by dividing the peak load by the cross sectional areas while the modulus was

determined by a linear regression of the stress-strain data (Fig. 3-5). The average of the

two strain gages was used as the strain for each stress level. The data shown in Fig. 3-5

do not extend to the rupture strength of the specimen because the strain capacity of the

strain gauges was exceeded.