PSI - Issue 10

N. Nikoloutsopoulos et al. / Procedia Structural Integrity 10 (2018) 141–147 N. Nikoloutsopoulos et al. / Structural Integrity Procedia 00 (2018) 000 – 000

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might provoke unexpected bending failure. The optimized techniques, referring to strength contribution, are A.2, D.2, E.2.a and F.2, but techniques A.3, A.2 and D.2 require drilling operations. From all the techniques D.2 has an excessively high cost of all the others and even it exceeds the required shear stress cannot be suggested. Techniques with the lower cost ( ≤ 22.00 € ) do not exceed the required shear stress.

4. Conclusions

The techniques investigated can be derived into three categories:  With drilling operations (A.1, A.2, A.3)  With smaller-scale drilling operations (C.1, C.2, C.3, D.1, D.2)  Without drilling operations (B.1, B.2, B.3, B.4, E.1.a, E.2.a, E.1.b, E.2.b, F.1, F.2)

The most effective ones are A.3 (four-sided single continuous jacket), C.3 (three-sided single jacket with rope anchorage) and B.4 (three-sided double jacket), which are also proved to be the most financially beneficial, too. The general conclusion is that the optimal techniques solutions that do not require drilling operation and exceed the required shear force are three-sided (U-shape) double jacket technique (B.4), double rope in two sided notch at 90 o - 3 positions technique (E.2.a), single rope in two sided notch at 45 o technique (F.1) and double rope in two sided notch at 45 o technique (F.2). Among the four techniques solutions (B.4, F.2.a, F.1, F.2) the most efficient are B.4 (45.68 kN) and F.2 (42.68 kN). The last one (F.2) is the innovation of this study and it was proved that this technique is highly effective. It is expected that it will be widely used in construction when its cost will be declined.

Acknowledgements

The authors would like to thank Sika Hellas A.B.E.E. for sponsoring the materials for the strengthening of the specimens.

References

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