PSI - Issue 17

Piotr Smarzewski / Procedia Structural Integrity 17 (2019) 5–12 Piotr Smarzewski / Structural Integrity Procedia 00 (2019) 000 – 000

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Fig. 2. (a) Variation of the modulus of elasticity with SF content; (b) Modulus of elasticity versus compressive strength at 28 days.

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Fig. 3. (a) Variation of tensile splitting strength with SF content; (b) Tensile splitting strength versus compressive strength at 28 days.

Fig. 3b shows the tensile splitting strength versus the compressive strength of the HPC specimens. Silica fume appears to have marked influence on the tensile splitting strength. Ten percent SF implies that the mean tensile strength increases by some 27% at 28 days. The results also indicated that the tensile splitting strength was reduced markedly when the SF content was increased from 10% to 25%. 3.4. Fracture properties The notched beam specimens were loaded in a three point loading set-up with two supports located at the distance of 600 mm and loading point placed at beam mid-span according to the RILEM TC 89-FMT recommendation. A notch with a thickness of 3 mm and a depth of 50 mm was created in the mid-span. In order to fix the gauge clip, two plates were glued near the notch. The loading rate during the examination was 0.05 mm/min. The crack mouth opening displacement (CMOD) and corresponding load were measured. The deflections were recorded by means of linear variable displacement transducers (LVDT) mounted at the bottom of the specimen mid-span. The examples of load deflection curves are shown in Fig. 4.