Innovative punching shear reinforcement for foundations

The larger the buildings, the higher the shear forces that act at points on reinforced-concrete slabs. To prevent punching of columns through concrete slabs, punching shear reinforcement, commonly in the form of double-headed studs or link reinforcement, is often used in the loaded areas of columns. With HDB-Z punching shear reinforcement, Halfen has now developed a solution specifically optimized for application in foundations.


Load concentration results in higher stress

What applies to flat slabs, applies equally to ground slabs and foundations: smaller load concentration areas at columns result in high shear forces that act on floor slabs or foundations. The time-tested HDB-Z double-headed anchor and the anchor plate between the Z-anchors ensure low-slip anchorage in the concrete component.

In addition to optimized Z-shaped HDB-Z reinforcement, the resulting shear crack is crossed several times. In this way, the opposing crack borders are effectively clamped together. As a result, the resistance in the structural elements are markedly increased compared to conventional solutions.


New punching shear reinforcement saves time and money

Higher resistance to punching failure by up to 40 % over conventional link reinforcement can be achieved with the time-tested HDB stud rail alone. With the new HDB-Z, moreover, a considerable increase in loadbearing capacity is possible. The loadbearing capacity, up to 100 % greater compared to a foundation without punching shear reinforcement, can also be used to considerably reduce the thickness of foundations.  This, in turn, saves excavation quantity, amount of concrete and construction time. Added to this is the saving potential that includes disposal of the soil material that results during placement of the concrete and formwork.

For precast construction, additional savings in transportation costs can be achieved from optimized sizing of the foundations. For large buildings with high foundation thickness, there particularly results great overall potential for time and cost savings.


Free-of-charge design software

The design of the HDB-Z takes place with time-tested and user-friendly HDB software, the same as for the HDB stud rail. The software provides structural verification quickly and reliably. It furthermore automatically generates the parts lists as well as DXF files for implementing the CAD programs. The HDB software can be downloaded free of charge at halfen.de

Halfen GmbH
Liebigstr. 14
40764 Langenfeld/Germany
+49 2173 970-0

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