Fortskridande ras i prefabricerade betongkonstruktioner

Sammanfattning: The thesis about progressive collapse in precast concrete structures started because of the construction industry which has a new standard to internationalize the industry. The new standard is called Eurocode and requires houses that have more than five floors to have vertical bindings Problems have been discovered when a supporting wall gets knocked out for an unknown reason, such as a gas explosion or a collision of a car or a train. After the supporting wall gets knocked out, the house should stand more or less intact. Research began by reviewing the basics, such as wall- and floor choices and then specify on the drawstrings. To provide an understanding of what a drawstring is, the next step is to describe horizontal drawstrings, interior drawstrings and drawstrings along the edge. The paper also explains the new Eurocode. After investigation of the Eurocode, it turned out that it is not consistent and that the parts do not match. These differences are cited and commented in the report. Since it is impossible to decide which of EN 1990, EN 1991-1-7, EN 1992-1-1 should be used, calculations are made in two different ways, which gives a big difference in how much the vertical bindings will have to carry. The discussion addresses how the research has been progressed in chronological order. Here are the most sensible thoughts and ideas, developed in the meantime. The result of this work was a mixture of a vertical drawstring and alternative carrying. Keywords: Progressive collapse, vertical drawstrings, vertical ties, alternative carrying, precast concrete walls.