## 2 Geological Settings
it was determined that the landslides in Cortanovci should not be repaired because it would be irrational to repair the entire slope for the purpose of building a high-speed railway. In most of the area, the railway route was changed by moving to the plain area, and the bridge construction for the railway was made on deep piles. Such a solution is extremely expensive yet more rational than performing the reparation of large landslides. However, it should be emphasized that the conclusions have been reached in accordance with exceptionally detailed and extensive geotechnical investigations that had been performed previously. In addition, a large number of investigation boreholes, deep investigation excavations (3 m \(\times\) 2 m \(\times\) 35 m), and extensive geomechanical laboratory tests were performed, accompanied by geostatic calculations. A large bridge on the Danube was built in the landslide zone of Beska. Despite the fact that the bridge was known to lie on a landslide (Figure 8), after its completion, serious problems arose, and the bridge had to be repaired immediately. The main recovery measures consisted of the production of deep piles. Part of the bridge near Beska, on the right bank of the Danube, has six pillars with 45 m to 60 m distance between them. Figure 9 shows only pillar site 45, lithological soil types in the zone of that pillar, originally constructed piles, and additionally constructed deepened piles as parts of the remediation. The deepened piles are finished in marl blue clay, middle 4, which forms a stable part of the terrain. Deepened piles were also made for pillars 44 and 46 (Figure 8). For pillar 45, 10 drilled piles with a diameter of D = 0.90 m were made, with the base of the piles at an elevation of 70.50 m. In addition to the fact that the rehabilitation envisaged and performed deepened the drilled piles to the required length, other rehabilitation measures were applied, such as drainage, making a stone bank revetment, reliefing, and landscing in the bridge area. Landslides of the Danube type occur near the Beska bridge and the viaduct on the Belgrade-Budapest high-speed railway line in Cortanovci. These landslides have not been depicted in greater detail here because they occurred in nearly the same geological structure of the terrain as the landslide near the Sloboda bridge in Novi Sad. General conclusions, based on the overall knowledge of Danube-type landslides, are given later in this paper. Figure 8: Bridge on the Beska landslide. Figure 7: Viaduct on the Cortanovci landslide zone of the Sloboda bridge. General Observations on Deep Landslides along the Danube on the Fruska Gora Slopes and Recommendations for the Approach to Remediation  
Experience in studying landslides shows that the first phase consists of identifying the landslide geometry and the essential terrain properties. In the following stages, the research is aimed at specifying the individual details that were left unresolved in the previous phase. In the last phase, when reparation solutions are designed, the research is aimed at identifying details important for adjusting specific repair measures to the actual natural conditions. There are similarities between landslides on the above relatively large area stretch, but some peculiarities were also found that can be of great importance. The general conclusions about landslides presented in this paper could be very important in the future study of insufficiently examined slopes along the Danube. The following are the most important considerations for Danube-type landslides:  
* They affect the area from the deepest part of the Danube riverbed and the slopes up to the loess sections;
* In the zone of frontal scars, on almost all unstable slopes, there are prominent long morphological depressions;
* Almost continuously, with brief interruptions, landslides are affecting the right valley side of the Danube.