Connectors for Timber-Lightweight Concrete Composite Structures

In timber-concrete composite structures (TCCSs), a timber member is connected to a concrete slab so that the timber primarily resists tensile forces and the concrete resists compressive forces generated from flexure. In Europe, renovating historical timber floors to TCCS has become the most prevalent market for the usage of this technology. The addition of a concrete slab to a timber floor makes the system performance competitive to reinforced concrete floors. The horizontal timber-concrete interface is the challenge of the TCCS. Various connectors are on the market with a wide range of stiffnesses and load capacities which are crucial design parameters for TCCSs and empirically determined by tests. The results of push-out tests with five different connectors are presented. A lightweight concrete (LC) with a density of 1.6 kN/m3 (100 lb/ft3) was used as the concrete floor in the samples. The application of LC provides an interesting variation in TCCS technology to minimize the dead load on the timber floors. Results show that the combination of stiffness and capacity are crucial in choosing an economical connector.