Vízügyi Közlemények, 1973 (55. évfolyam)

4. füzet - Rövidebb közlemények és beszámolók

(43) The latter carries it to waste. The moving rack operates successfully and although manual labour is eliminated, some supervision is necessary. :i. Nagt), Tibor, Mech, Engr.: Mechanical driving of sheet piles in flood fightings and drainage work (For the Hungarian text see pp. 248) Problems related to the mechanical driving and drawing of sheet piles, as well as to site illumination are considered. For cutting off, or extending the path of seepage through flood levees "Pátria" type channel piles of 4, 6 and 8 m length are driven ( Fig. 1 ). The pile with the new lock design ( Fig. 2) has recently been developed by the Central Flood I'ighting and Drainage Organization. The new joint type makes driving work easier. The piles are driven manually from a scaffold using driving hammers by Atlas-Copco of the types P-60, P-80S, or TEP-40 (Fig.3). The piles driven to 2-3 m depth are driven deeper by DEMAG FR — 200 and FR — 220-type pile drivers operating from ladder scaffolds (Fig. 4). A new type of driver, VR-2, operates pneumatically from a scaffold ( Fig. 5) and is low in labour demand. The driver Type H-2S (Fig. 6) operates on the two-stroke gasoline engine principle. The main technical data of the drivers are compiled in Table I. For withdrawing the sheet piles the pneumatic devices PZ-1 and PZ-2 by DEMAG (Fig. 7) are used, suspended from truck cranes. The data on these are compiled in Table II. Further problems involve the mechanisation of attendant operations, using pneumatic devices. Night work of the flood fighting teams is facilitated by means of 4 to 5 kVA capacity, portable generators. Lighting for longer sections is provided by trailermounted generating sets of 30 kVA capacity. Babusa, Pál and Sarlós, Miklós, Civ. Engrs. : Construction of pumping stations in Szigetköz (For the Hungarian text see pp. 254) The lower bay in the Szigetköz area along the Hungarian Upper Danube reach is round 120 sq.km in area. Owing to the great depth of permeable gravel subsoil seepage waters emerge at high Danube stages, for the removal of which three pumping stations were constructed, namely at Györzámoly, on the Szavai Main Canal and on the Bácsa Principal Canal, each with a capacity of 4 cu.m/sec discharge was also provided. The pumping plants were designed with caisson foundations ( Fig. 2). After lowering the bottom of the caissons was closed by underwater concrete. Impervious concrete was used for each sidewall of the machine room. The sinking diagram of the caissons is shown in Fig. 3. At the Szavai pumping station the gravelly-sand subsoil caused serious delays, so that the designs had to be modified. At the Bácsa pumping station the 362 sq.m construction pit was unwatered without any particular difficulty by means of two filter wells. As a result of the successful groundwater-lowering operation it became possible to adopt a raft foundation and to reduce construction costs by 2.9 million Forints.