Behavior of Cracked Grout Bodies of Micro-Piles with Different Corrosion Protection Measures

Tensile elements are used for various geotechnical tasks to transfer loads into the subsoil. With the requirements regarding load-bearing capacity (ULS) and serviceability (SLS), additional issues, such as their durability, must be considered in the design. Due to subsoil properties and groundwater, insufficient corrosion protection can lead to massive corrosion damage of tensile elements. In addition to the effects on service life, such damage can also influence the serviceability and, subsequently, the load-bearing capacity. Therefore, different corrosion protection systems depend on subsoil conditions, the planned service life, and external influences. This paper presents investigations dealing with the issue of corrosion due to cracking of the grout body of micro-piles. In two tests, samples with different corrosion protection measures were subjected to tensile stresses. In addition to a visual recording of the crack patterns, computer tomographic scans were carried out. Therefore, in addition to verifying the crack formation, these investigations allowed us to evaluate the “interior” of the grout body. Thus, the studies provide information on the function of different corrosion protection measures.