A tree does what no building does, namely repairing the weak spots in the construction-2

In order to bring the concept of living tree buildings to
the next level, solutions have to be found for possible
technical and non-technical drawbacks. Technical points
of attention are the longer construction time, the need
for a flexible or growing façade and the uncertainty
about the safety of the structure. A longer construction
time is a technical point of attention on which the focus
lays. Some solutions to reduce this construction time
have not been tested yet. The focus in the research
done for this graduation project will be on one of
these, namely the comparison of connection methods.
Non-technical points of attention are the acceptance
by the user or stakeholders involved and trees which
contain toxic substances. These points of attention are
also taken into account in this research, but in a less
dominant role, while the focus is on the technical aspects
of building with living trees.
The design assignment for the Living Tree Pavilion was
to design a building which is a research object for the TU
Delft to test the load bearing capacity of the structure,
in particular of the connections, as well as to design a
building that inspires people and shows the possibilities
of living tree structures as load bearing structure.
The Living Tree Pavilion is a pavilion of which the load
bearing structure exists of living trees. It is an open
dome-shaped building with a diameter of six meters
and contains at four meters height a platform on which
people can walk. The design of the Living Tree Pavilion
fulfills the stated demands and wishes in a more than
satisfactory way.
After 10 years the structural elements are expected to be
able to carry the loads. Grafts are expected to transfer
tension forces, a moment or a shear force better than
an axial weld, due to the larger area of common rings.
In the connections a larger surface is needed to take up
the tension stresses perpendicular to the grain due than
to take up the compression stresses perpendicular to
the grain. Whether the structure will indeed be able to
carry the loads after 10 years, depends on the accuracy
of the assumptions. Most assumptions made increase
the safety margin, except for the assumed growth speed
of the trees. Further research into the assumptions and
research data of the Living Tree Pavilion itself can help to
determine more accurately the time the structure needs
to carry the loads. Taking into account the large safety
margins in this calculation, the amount of years might be
reduced.