LGRB-BW BK50: Excavability up to 1 m depth

In order to assess the “especially difficult geology” according to VwV broadband funding (Pt. 8.6) from 01.08.2015, the maps in the LGRB are evaluated using a uniform method of excavability throughout Germany. It is part of the Methodological Documentation Soil Science of the State Geological Services. The numbers listed in the card legend in subsequent brackets indicate the eight rating categories described therein. However, this method and the information derived from it does not replace DIN18300 (VOB Publication and Contract Regulations for Construction Services). From the available medium-sized soil and geological maps and data, no parcel-sharp statements and no assessment of the subsurface classes according to DIN 18300, e.g. for tenders and cost calculations, can be derived. Sites with strong influence by ground, slope or reservoir water are designated separately. When opening, pipe trenches can be quickly compressed, e.g. by soft soil masses lying in groundwater, so that temporary installation is required. Reservoir water occurs when a low water permeable soil layer hinders the downward movement of the leachate in the soil. The near-surface water is formed especially after extensive rainfall or after snow melting. With prolonged drought and due to the water consumption of vegetation, it usually disappears during the growing season. In the case of a pipeline construction in spring, free soil water, comparable to groundwater sites, is to be expected here, while dry soil layers are found in late summer and autumn.