Zum Lastabtragungsmechanismus von vorgespannten Auftriebsankern

To the mechanism of load transference of ground anchors for buoyancy protection. For the evaluation of the mechanism of load transference of ground anchors for buoyancy protection a simple substitute spring model is provided, with which an anchor load test can be simulated according to DIN 4125. The investigation shows that not flushing out the borehole can decrease the anchor effect due to buoyancy protection. A test of the free anchor length is not necessarily detecting this restriction.     

Zum Tragverhalten von Mauerwerksbauten unter Erdbebenbelastung

Behaviour of masonry structures under earthquake loading. The objective of the seismic design of structures is to provide sufficient resistance considering the ductility of the structure. With experiments on storey‐high walls at the University of Dortmund the performance of masonry shear walls under simulated earthquake loading was identified up to failure. The nonlinear behaviour of the walls was evaluated with regard to resistance and potential for ductility. Depending on the type of the limit state the walls exhibited different quantities of ductility. Analyses showed that within certain limits mechanisms with higher ductility can be attained by appropriate tuning of the structural parameters. Considering configurations of walls typical for terraced houses and apartment buildings the structural ductility and the corresponding behaviour factors for seismic design (see EC 8 and DIN 4149) were assessed.     

Zum Feuerwiderstand von Stahlbetonstützen

Fire Resistance of Reinforced Concrete Columns This contrubution shows studies to fire resistance of reinforced concrete columns, based on a structural analysis with an advanced calculation model. The analysis covers simply supported columns as well as cantilever columns with buckling length in case of fire up to 20.0 m. For simply supported columns in multistorey‐buildings a new classification table will be suggested because of the general storey height of approximately 4.0 m. Cantilever columns can be classified in fire resistance classes in compliance with praktice conditions (Level‐1 method). Finally safety considerations for reinforced concrete columns will be performed, which show, that existing concrete columns, which are designed in conformity with the minimum dimensions of german standards (table 31 in DIN 4102‐4), are stable in case of fire, if they are planned and built in compliance to acknowledged rules of technology.