Hydraulischer Grundbruch - Formel zur Ermittlung der erforderlichen Einbindetiefe

Hydraulic heave - Formula to determine the required embedded length

In Bautechnik 86 (2009), Vol. 9 [1] first results of the investigations on hydraulic heave and the required embedded length for homogenous, isotropic soil have been presented. These investigations have been continued for spatial conditions and have been extended to both stratified and anisotropic soil. More than 100 design charts (see [2]) have been evolved from these results. These design charts allow the determination of the required embedded length considering the soil conditions and the geometrical conditions. In addition to the numerical investigations and the related design charts a formula for the determination of the required embedded length has been developed. The basic formula is quite simple and can be used for two-dimensional conditions. However an extended formula can be used for spatial conditions, separated for the corner, the front and the long side of construction pits. Furthermore by the use of add-ons the formula allows the determination of the required length for anisotropic or stratified soil as well as for different unity weights or a variant safety-level. Hence the formula is a tool which can replace extensive calculations in many cases or can provide realistic reference values for complicated construction pits and soil conditions. Moreover the formula can be implemented into software for the determination of the statically required embedded length. Thus the effortful switchover between software for the static and flow calculation becomes lapsed.