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also be (partly) reused. However, additional time and effort TCC shear connectors on the market is currently quite limited.
are required in order to separate the TCC slab from the A few solutions have been proposed in recent research
building frame. works, which have been classifed in the following section
Reusing the individual parts: this option considers the based on their target construction method. The review of
reuse of individual parts of the TCC slab (e.g., concrete slab, the literature in this section aims for a general overview of
GLT beams, CLT plates) in new applications. Direct reuse the existing solutions.

of the concrete slab in a similar foor application could be
challenging (i.e., reusing the concrete slab as-is) because the Solutions for the Dry–Dry System
concrete slabs in TCC foors are typically relatively thin and The dry–dry system refers to a construction method in
have a small amount of reinforcement. However, reusing these which the concrete slab is prefabricated separately and then
concrete slabs in alternative applications, e.g., with lower load connected to the timber component, either offsite or onsite.
capacity requirements, could be possible. Previous research works on the development of deconstructable
Timber components, however, offer a higher fexibility for solutions have mostly focused on the dry–dry system.
reuse in general. A recent life cycle analysis on TCC foors In one of the early studies on the subject, Lukaszewska
has also highlighted the potential of reusing the entire timber developed and evaluated the mechanical properties of a

components. However, in this case, some challenges also prefabricated TCC system in which several connection systems
exist in terms of, uncertainty in the mechanical properties, were applied.
which justifes in-depth research and development projects. One of their proposed connection systems, made with
Anyhow, in order to fully achieve the benefts of reusing a steel tube and a coach screw, had the ability to be
individual parts of the TCC slab, deconstructable shear deconstructed. This connector could be used in combination
connectors are required. Furthermore, a deconstructable slab with a notch as well.
to post/column connector could be benefcial, as described Some connection systems were also tested by Crocetti et

previously, for reusing entire TCC slabs. al., which have the potential to be used in DfD, including one
In addition to reusing, the recycling of materials (or part connection made with a steel tube and screws. Khorsandnia
of them) might also be suitable. The timber offcuts and the et al. specifcally considered DfD principles as one of their
individual materials in the concrete slab (e.g., steel bars, metallic justifcations for developing new deconstructable connectors in
connectors). However, even if conventional demolition is applied TCC foors. They examined several different solutions, which
rather than the proposed reuse options, deconstructable were made using either bolts or screws in combination with
connections would be benefcial when recycling and partially other elements made with steel, wood, or plastic materials.
reusing these materials, which should be considered in order
to minimise material waste. Solutions for the Wet–Dry System

The wet–dry system refers to a construction method in which
Existing Deconstructable TCC Connections Suitable for the connectors are mounted on the timber component,
DfD and then concrete is cast on top. This can be performed
To achieve the full potential of material recovery for reuse in either offsite, in the case of prefabrication, or onsite in the
TCC foors, deconstructable connectors are essentially important. conventional cast-in situ approach. The wet–dry system is the
In this case, although some practical deconstructable slab-to- most common method for fabricating TCC foors; however,
post/column connectors exist, the availability of deconstructable only a few studies have considered applying deconstructable