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Fastenings in concrete are widely applicable in construction. A significant benefit of fastening technology lies in the fact that it can adapt to various geometries and construction sequences. As a result, the need to design and realize a fastening in structural elements with unconventional geometric configurations can be encountered. Existing design standards rely on the concrete capacity design (CCD) method for concrete‐related failures, which typically covers detailing situations with rectangular configurations of the fastenings and the concrete members. However, the lack of guidelines for a wider range of applications may lead to over‐conservative dimensioning or design constraints. This study investigates the influence of beveled concrete edges on the load‐bearing behavior of anchors. As part of the research, a series of experiments and numerical simulations were conducted. The results derived from the investigations are used to develop an analytical concept that extends the area of applicability of the CCD method and can be used for reliable dimensioning of fastenings close to non‐rectangular concrete edges and geometrical boundaries. [ABSTRACT FROM AUTHOR]

Embed plates anchored with welded deformed reinforcing bars or heavy-gauge deformed wire are commonly used for attachments in nuclear facilities. These connections may experience significant tension and/or shear. The required embedment of the welded bars is typically determined based on development length concepts, with the assumption that the nominal tensile capacity of the connection can be taken as the tension yield strength of the bars. This paper presents results of large-scale experimental investigations conducted to evaluate the tensile capacity of such embed plates. Single anchor pullout test results are also presented to categorize bond behavior for deformed reinforcing bar anchors (DRAs) and deformed wire anchors (DWAs). Preliminary results indicate that adoption of the design paradigm given in the Code for the concrete-governed strength of bonded anchors can provide a reasonable approximation for DRAs but requires additional calibration and study for application to DWAs owing to their diminished bond capacity. [ABSTRACT FROM AUTHOR]

The paper presents the results of a numerical analysis (FEM) describing the effect of the undercutting head angle on the formation of the rock mass failure zone during the initial stages of failure propagation. The research was carried out in the context of developing a technology for rock extraction by controlled pull-out of undercut anchors installed in the rock mass. The focus was on the initial stage of crack propagation and its trajectory for anchors embedded at an assumed constant depth and a value of the friction coefficient of the rock against the anchor head. It is shown that smaller angles favor smaller stripping angles and an increased radial impact of the head on the rock material (in the plane perpendicular to the head axis), while the impact of heads with larger angles is found to favor larger fracture penetration angles and faster penetration towards the free rock surface. [ABSTRACT FROM AUTHOR]