In case, concrete cone failure calculation, for EC2 part 2 is calculated with pyramid shape, In the fact that, concrete breaks is with cone-shaped. Why we use pyramid shape instead of cone-shaped? This impacts on precision results? Thank you!
Hello Thuyết,
Thank you for reaching out to Hilti.
The concrete cone failure is focused especially on the group of anchors close to edges (edge breakout). The concrete cone is idealized as a pyramid with a height equal to hef because of the ease of calculation and undertaking the conservative approach towards designing. In principle, the base of reference projected concrete failure area of a single anchor is approximated as a square that results from projecting the failure surface. For example, consider if you have multiple anchors spaced close to each other; it would be then harder to determine the area of the concrete cone. Hence, the codes undertakes the conservative approach and consider the top part of the concrete cone as square/rectangle.
Hope this helps.
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Team Ask Hilti SEA