Расчёт анкерного болта на действие осевой растягивающей силы

Abstract

The article analyzes the performance of anchor bolts with a bend installed in a concrete base. Numerous studies and tests have revealed three main failure mechanisms of the anchor bolts under axial tensile loads: failure by the metal of the anchor bolt, failure caused by loss of bond between the anchor bolt body and the surrounding concrete mass ("slippage" of the anchor in the base), and failure caused by spalling of the concrete cone surrounding the anchor from the base. The anchor bolt calculations have to determine the ultimate loads for each of these failures considering the diameter and material of the anchor, the strength characteristics of the foundation, and the anchorage depth. This problem is topical since the current Appendix D to SP 43.13330.2012 contains no procedure for the calculation of carrying capacity of such connections for each of the mentioned failure modes and the anchorage depth is assigned according to the anchor bolt diameter, which in some cases results in considerable reserves (economically inexpedient) or is simply not realizable (for example, when the anchor bolts are installed into the foundation of a small thickness). Besides, in contrast, for example, to foreign recommendations for anchors installation in a ready-made foundation, there is no technique in Appendix D to SP 43.13330.2012 which takes into consideration the edge and interaxial spacing and its effect on the carrying capacity of the anchor bolts.

In connection with the above-mentioned, the article offers the methods of anchor bolt calculation corresponding to the main mechanisms of their destruction under the action of axial tensile and shear loads as well as their combinations.