Impact of the Degree of Concrete Cracking on the Pull-out Resistance of Steel and Plastic/Metal Sleeve Anchors

Areas affected by seismic and mining disturbances are tied to a risk of damage to engineering structures. The problem may result in permanent damaging of fasteners installed in buildings. Such damage may affect the strength of different types of construction fasteners and connectors. The technical condition of fastening elements should be assessed, and conclusions formed regarding the causes of damage and ways to secure those elements. In order to determine the pull-out resistance of fasteners set in a concrete base, the effects of disturbances were simulated as cracks in the concrete. Additionally, the influence of tolerances for openings made using drills with diameters dmin, dnom and dmax presented in the study was also determined. Introduction of the variables described may influence the pull-out resistance of the steel and plastic/metal anchors. The article presents the results of tests for specific pull-out resistances of steel and plastic/metal anchors installed in a concrete base in normal-weight non-cracked concrete and normal-weight cracked concrete where crack initiation was at 0.20 mm and 0.35 mm. All tests were carried out for the purposes of this paper at normal temperature and with C20/25 concrete, without factoring in influence of concrete or air moisture content.