Geotechnical conditions for E-763 motorway construction from Belgrade to south Adriatic across the landslide Umka - Duboko
|Location||International Geological Congress,oslo 2008|
|Author||Jelisavac, Branko; Milenkovic, Svetozar; Jotic, Milovan; Vujanic, Vladeta|
|Holding Date||07 October 2008|
Belgrade rolling area and its surroundings are known for numerous landslide phenomena. This is particularly stressed in the valley banks of rivers Sava and Danube and their respective tributaries. The slopes of valley banks thereof are made of miopliocene complexes of "softer" rocks: clays, marls and sand. Basic cause of the occurrence of landslides is awarded to complex geologic and morphologic evolution of terrain. However, direct motive, in our time is more often the result of human economic and building activity.
By both General and Preliminary designs of motorway from Belgrade to South Adriatic, i.e. E-763, at the exit from Belgrade, road facility corridor is located at the right bank of Sava river crossing the landslide Umka-Duboko in the length of 3 km. Large active landslide in the depth of 10-26 m, created in marly clays, takes up the area of 1.8 sq.km.
In order to find an optimal and safe location of future transport facility at that time extensive geologic-geotechnical investigations and monitoring of Umka-Duboko landslide were undertaken. A series of variants were considered as follows: tunnel, two bridges across the river Sava, relocation of river channel, along the river shore, etc. The corridor of future motorway located along the right bank of Sava river has been selected on the findings of new General design. Additional geotechnical investigations have been undertaken and Preliminary design of section Umka - Obrenovac, in the length of 7.65 km, which is encompassing the repair of landslide, about 3 km long, has been prepared. This complex issue demanded extensive interdisciplinary investigations and analyses.
In order to define the geologic composition, causes, mechanism and dynamics of the landslide thereof for the purpose of preparing the design for terrain repair and watercourse regulation, extensive geotechnical investigations and monitoring have been carried out. The auscultation network has been installed including 180 measuring spots, 33 inclinometers, 25 piezometers, survey pegs, wells, river profiles, etc.
Investigation results have provided for landslide repair solutions which guarantee the stability of future motorway and also stabilize the remaining parts of unstable slopes on which some 500 housing facilities and cottages are jeopardized.