Classic systems generally employed for connecting three-layer sandwich elements, such as flat anchors, sleeve anchors, SPA but also plastic-based systems, are without exception ‘only’ approved for utilisation in normal concrete. Philipp has now made it possible to use its flat anchor system in lightweight concrete as well.

Compared to normal concrete, there are several types of lightweight concrete – structural lightweight concrete (LC), lightweight aggregate concrete (LAC) and autoclaved aerated (lightweight) concrete. The focus of the new application described in the following is on structural lightweight concrete, which is characterised by a better bond between the hardened cement paste and the aggregate compared to normal concrete. However, the most important argument in favour of the use of structural lightweight concrete is its lower bulk density and thus its weight. This is achieved by adding lightweight aggregates with a lower bulk density, usually expanded clay, expanded glass, expanded slate or natural pumice, as is regulated in DIN EN 13055.

Sandwich elements made from lightweight concrete are widely employed in the most varied types of utility facilities, in residential construction as well as in public and commercial building projects. It was then a logical step for Philipp to open up new areas of application for its well-proven sandwich panel anchors and to support lightweight concrete construction methods with a connection solution unique up to this time. The flat anchor system was quickly chosen for this application in lightweight concrete on account of its thin, sheet-like shape and easy handling.

User-friendly SWA software facilitates dimensioning

The application was limited to structural lightweight concrete (LC) of quality classes LC30/33-LC50/55 with a D2.0 bulk density class. The proportion of lightweight aggregates, in this case expanded clay, must not exceed 200 kg/m3 of lightweight concrete in order to fully comply with the specifications of the approval. All known flat anchor sizes, and connector pins exclusively, are envisaged for this use in lightweight concrete, with design resistances against concrete cone failure partially staggered (see approval, annex 21).

Dimensioning the connections is facilitated as usual by user-friendly Philipp SWA software, which is available for download in a new version (V3.31.06).