Plastic anchors consist of a plastic sleeve and a special screw or nail. In Germany the sleeve is made of polyamide PA6 or PA6.6. The behaviour of plastic anchors in concrete is influenced by different parameters changing the properties of the plastic (e.g. temperature, water content). Furthermore, the behaviour of plastic anchors in concrete is determined by the visco- elastic properties of the plastic (relaxation and creep). Therefore the pullout loads are dependent on time and load history. Other parameters affecting the pullout loads in concrete are the anchor type, the widths of cracks in the concrete, the drill bit diameter and the orientation of the sleeve in the cracks. The performance of plastic anchors in cracked and uncracked concrete has been investigated in pullout tests. In addition to tensile tests, creep tests and tests in opening and closing cracks have been performed. In tests in which the splitting force of plastic anchors has been measured the basic behaviour of plastic anchors in concrete has been investigated.
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