Upgrade of Långströmmen dam for higher safety standard
2015 (English)Conference paper (Refereed)
Långströmmen, a high-hazed facility, is planned for rehabilitation in the light of the existing dam-safety guidelines. The safety evaluations made during the recent years have revealed a number of deficiencies with respect to its spillway discharge capacity, rock erosion downstream, dam spillway stability, status of embankment dams and functions of mechanical and electrical systems. After investigations of a number of rebuilding alternatives, economic and technical considerations have reduced to one option, i.e. construction of a new gated spillway with a stilling basin. Three reservoir levels are considered, which also result in different requirements for the spillway stability and freeboards of the embankment dams. The new 18 m spillway is placed separately, with an 80 m sloping chute followed by a stilling basin. To assist in the rebuilding design, hydraulic model tests have been performed. For the reservoir area, the main issues of concern are flow patterns and head losses from the reservoir to the new spillway. For the existing spillway, attentions are paid to the river bank erosion downstream and energy dissipation. For the new spillway, the model study focuses mainly on its orientation, threshold elevation, discharge capacity and energy dissipation.
Place, publisher, year, edition, pages
Långströmmen, dam safey, design flood, rebuilding, model tests
IdentifiersURN: urn:nbn:se:kth:diva-179748OAI: oai:DiVA.org:kth-179748DiVA: diva2:889221
HydroVision International 2015, July 2015, Portland, USA
QS 20162015-12-222015-12-222016-01-04Bibliographically approved