US Patent 10156068 Built-up system, connector thereof, and method of making same

A connector for connecting a wood substrate to a concrete layer. The connector comprising a shank adapted to engagement with a bore in the wood substrate with a length of the shank aligned with a central axis of the bore, the shank having at least an external portion made of a cement-based composition. In the built-up system, the connectors can have transversal ductile collapse characteristics providing a structural ductility of at least 50% to the built-up system with the wood substrate and concrete layer maintaining an elastic behavior upon the transversal ductile collapse of the plurality of connectors.