Nachweisverfahren zur Tragfähigkeit überwiegend axial beanspruchter Grouted Joints in Offshore-Tragstrukturen

Design of axially loaded grouted joints of offshore support structures.

Grouted joints in spatial substructures of offshore wind turbines in deeper waters are prevailing axially loaded and due to installation procedures equipped with large grout annulus. Current design standards recommend the verification of the structural and fatigue behaviour using engineering models. The engineering models originate from empirical analyses and scaled tests including combined loading with Portland cement core for defined ranges of validity. The design with these formulae includes the calculation of the compression strut and the grout matrix failure. In case of deviating geometries or use of ultra high performance grouts, the actual axial strength of grouted joints is underestimated. Within this paper an enhanced engineering model based on simple structural mechanics is presented which incorporates influences of high performance grouts and confinement effects. Thus, an appropriate estimation of the axial strength for axially loaded grouted joints in offshore substructures is possible.