Impact of contact interface conditions on the axial load bearing capacity of grouted connections

authored by

Peter Schaumann, Alexander Raba, Anne Bechtel

Abstract

Grouted joints used in lattice support structures such as tripods or jackets for offshore wind turbines demand for reliable and economic design regulations. Current standards are not valid for executed geometries and used grout material due to the experimental background for which the design approaches were developed. Moreover, fatigue capacities of grouted joints are estimated without an acknowledged design model. To improve the design regulations for predominantly axial loaded grouted connections, a research project is conducted at the Institutes for Steel Construction and Building Materials Science, Leibniz University Hannover. Within this project small and large scale grouted joint specimens are tested under fatigue loading conditions. Additionally, influencing factors of varying contact specification at the interface between steel and grout are investigated. This paper introduces the test setups and describes results of surface roughness measurements of the specimens. The measurements are within the expected ranges of surface roughness for steel. In addition, results from small scale tests conducted submerged in water are presented. It becomes apparent, that water at the interface between steel and grout significantly reduces the fatigue performance of grouted joints. As one reason, hydro lubrication reducing the friction coefficient between steel and grout and leading to higher stress concentrations can be stated. Furthermore, a dependency on the test load frequency was observed, so that higher frequencies have a negative impact on the fatigue performance.

Organisation(s)

Institute of Steel Construction

Type

Conference contribution

Pages

1990-1999

No. of pages

10

Publication date

2013

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Renewable Energy, Sustainability and the Environment

Sustainable Development Goals

SDG 7 - Affordable and Clean Energy