Octagonal pedestals

Figure 3.7 Reinforcement for Resisting Anchor Tension in Octagonal Pedestals...

Wey, E., Hayes, T., Naqvi, D. (2010), Concrete Breakout Strength in Tension for Vertical Vessel Anchorage in Octagon Pedestals, Proceedings of the Structures Congress, American Society of Civil Engineers Reston, VA. 

Tension force in anchors induces tensile stress in concrete due to bearing at the embedded anchor head or nut, which in turn induces lateral bursting forces. A recommended arrangement of reinforcement for resisting concrete tensile stress in pedestals of square, rectangular, and octagonal cross-section is shown in Figures 3.6 and 3.7. 

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