Acta Scientiarum Polonorum

A flyover constructed over 100 years ago was made of several dozen framework reinforced concrete structures
with a two-pile. Trestle system connected by bolts and the upper plate, and longitudinally joined by
connecting beams.This building, with a height of 11 m and a length of over 200 m to 1960s, served as a transshipment
dockside quay of the Oder with a light port crane moving on its crest. Lack of required technical
inspections, low concrete quality, and above all the lack of assessment of geotechnical conditions and operational
neglect were the main reason for the destruction of a 110-meter section of this structure. This occurred
during the period of lowering the water level in the river. The necessary geotechnical drilling, probing and
laboratory tests of the lands in the landslide zone, as well as research in the non-destructive zones and measurements
of the area of destruction made it possible to determine the complex causes of destruction. On the
basis of the identified slip line and previous incidental studies determined that the slip surface was initiated
in a small alluvial soils layer with a small contribution of dispersing pore high-pressure. The irrigation zone
drained to the ground of water could have a significant impact of slip away water from the adjacent building
and very low concrete strength. Damage in one zone resulted in progressive destruction on adjacent sections.
It was proved that the stability factors of the estacade for sliding and overturning were not met.