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Fixed Slab track NFF General Page: 131-01 General Information Gravel construction and conventional fixed slab track as e.g. the system NBU differ in the interface of base / railway track. Hydraulically Bound Base course (HGT) instead Sub Structure (PSS) and Concrete Base course (BTS) instead gravel. Gravel roads can be repaired in limits by considering height and position, in FF-systems, these ratios are possible in limits in rail fastenings. The gravel roads requires more maintenance and has a shorter life until the complete reconstruction, FF systems have a long life and requires less maintenance but a more elaborate preparation of the base (soil stabilisation, compaction, exchange etc.). The ThyssenKrupp GfT Gleistechnik GmbH comes with two different slab track (FF)-Systems: • System FF NBU • New slab track NFF New slab track - NFF In poor soils, the cost for this soil stabilisation increases enormously. Here begins the operational area of NFF. It accounts to all base course work, that the system NFF loads from the dead weight and rail traffic over deep foundation (bore piles, micro piles, etc.) directly initiates the bearing capacity of base course The necessary pickets and associated pile lengths are determined by a ground survey, so that only minimum setting can be done. Thus, the advantages of the conventional slab tracks (low maintenance cost, long life) are connected to safe load transfer through deep foundations (small settlements, no complex substructure etc.) the system NFF. The system "New slab track" (NFF) is looked from a structural point of view as a bridge-like construction with a railway track part. Chamber (cross-fall) +100mm Longitudinal support unit Chamber (cross-fall) +100mm Cross bar ↙ Drilling or micro piles. Fig. 1: Schematic representation of NFF, here with each 6 pickets per CROSS BAR Without scale/schematic diagram Date of issue 08/10