Vízügyi Közlemények, Kivonatok, 1965
Dégen Imre: Az 1965. évi dunai árvíz és árvízvédelmünk fejlődése
(27) of protection work is reflected by the circumstance that the considerable mechanized forces applied, reinforced the levees at. a higher rate than deterioration set in. In the most critical situation 40.000 men were engaged in flood defense. They were helped in their work by 300 earthmoving machines, 1200 dumpers and other transport vehicles. Saturation, sliding and slumping of the levee was counteracted by balasting with sandbags and quarry stone. The same materials were used for constructing counter-head basins against upward seepage, softening of the topcover and bails. Sandbags used as ballasting and construction material will continue to represent one of the most important materials in flood control, since they are easy to transport, shape and place, and they are capable of following any movement without the development of stresses (Figs. 12 to 14). On the riverside of the levee light section sheet piles driven as cutoffs over several kilometres were used as means of protection. Of these sheet piles 36.000 were used during the flood (Fig. 18). The efficiency of these cutoffs depended on the quality of driving. Plastic foils were successfully used for sealing eventual gaps. After the passage of the flood the trenches left behind the withdrawn cutoff walls were grouted with a bentonite mixture. Plastic foils did good service for stopping seepage, when placed on the riverside slope (Fig. 15), or for sealing crest dykes, ring-dykes, gates of sluices and counter-head basins, but they proved useful for protection againts wave action as well. Sublevee basins proved most effective against detrimental consequences of underseepage, boiling, piping and hydraulic soil failure. In the arrangement of sublevee basins it was found necessary to allow for the soil-physical properties of the topcover. Whereas on cohesive soils high counterheads could be maintained in a single sublevee basin, on sandy soils,, or on such susceptible to saturation and softening several rows had to be constructed and waterlevels staged accordingly. A wide variety of protecting methods was developed during the flood in accordance with the divergence of phenomena, differences of material of the levees and subsoil, non-uniformity of structure and the wide range of processes which took place in the levee and subsoil (Fig. 15 to 18). Future tasks in the development of the flood control system are outlined in Chapter II/ 5. During highwater 1 million cu.m of earth was moved to construct localization levees and ring-levees on the most critical places. These localization- and ring-levees will continue to form an important part of the flood control system. Construction of these levees during highwater should be prepared by tracing and surveying possible alignments in advance. The plain between the levees is the bed where floods must pass and its utilization must therefore be adjusted to interests of flood control. Along the bankline of the river a deforested strip of adequate width must be created and trees must be removed on the landside of the leves, for a
