Abstract: An electrode for determining corrosion of metal reinforcement in concrete includes a wire surrounded by insulation and made of a metal which is more electro-positive than a metal reinforcement. An electrically active part of the wire is in electrolytic contact with moisture in concrete surrounding the reinforcement. The insulation is disposed along the whole of the electrically active part of the wire in such a way that the insulation keeps this part of the wire separated from the reinforcement and galvanically insulated therefrom.

Abstract: A sheathing pipe for an anti-corrosion rod of steel is described, in which the inside of the sheathing pipe has at least one electrode that can make electrical contact with the outside.

Abstract: To lower ground water in the region of foundation bodies, such as foundation piles and the like, a water-pervious layer of filtering concrete, in particular of uniform-grained concrete, is arranged below an upper water-impervious part which is made of standard concrete. From this layer the entering ground water is sucked through a pipe which extends through the foundation body and is designed as a water-pervious filter pipe in the region of the layer of filtering concrete. The layer of filtering concrete is preferably reinforced by reinforcing irons. After lowering of the ground water level, the filtering concrete is injected with a hardenable injection material, thus enabling the lower end of the foundation body to better absorb the pressures transmitted from the upper part.