New criteria for assessment and
higher maximum water levels pose
higher requirements for retaining
walls and dams. Existing structures
must comply with completely new
requirements for stability caused by
higher freezing pressures, updated
earthquake load zones and new
requirements in terms of
impermeability and position stability
or stability against overturning.
For reinforcing and simultaneous
rehabilitation, this challenging
increase in load bearing capacity can
often be reached by a massive
anchoring of the dam structure. In
this case, boreholes are drilled
vertically from the dam crest, and
the dam wall is anchored at the
bottom using ground anchors. Lift-
off suction power can also be
overcome by anchoring overflow
structures and stilling basins
permanently into the soil using
anchors or tensile piles. Depending
on water levels, different load
conditions can also be safely
absorbed by anchors (in case of
tensile load only) or micropiles
(even for alternating loads) at
retaining dams. Caissons consisting
of driven sheet piles are built for
cofferdams or new quays. They are
assembled at the head using tie rod
systems and thus stabilized against
uplift during sand filling and against
subsequent loads resulting from dead
weight and traffic.