Page 19 - Designing Ways 247

2.0

2.0
B

2.5m ELEVATION A
2.0
3.5m
ELEVATION B
2.0
G 0.0m
B
11.7
ELEVATION C

16.6

2.0

against the balustrades) to the supports how the three R’s of sustainability • Compared to embedded reinforce-
in pure compression. Advanced discrete (Reduce, Reuse, Recycle) can be applied ment in concrete, Striatus uses
element modelling (DEM) was used to to concrete structures. external ties to absorb the thrust of
refine and optimise the blocks’ stereotomy its arched shape and dramatically
and to check stability of the entire Reduce: reduce the amount of steel required.
assembly under extreme loading cases or • Lowering embodied emissions A high carbon-intense material, steel
differential settlements of the supports. through structural geometry reinforcement (100% recycled) per
The bridge’s 53 3DCP voussoirs have and additive manufacturing that unit mass is more than ten times that
been produced using non-parallel print minimises the consumption of a standard concrete.
layers that are orthogonal to the dominant of resources and eliminates
flow of forces. This avoids delamination construction waste. Reuse:
between the print layers as they are held • Placing concrete only there where • Improving circularity and
together in compression. The additive needed, 3DCP minimises the longevity. Unlike conventional
manufacturing process ensures the amount of material required, while reinforced concrete structures,
structural depth of the components can the low-stress, compression-only Striatus is designed to be dry
be achieved without producing blocks funicular geometry of Striatus assembled without any binder
with a solid section, hence reducing the proposes the further development or glue, enabling the bridge to
amount of material needed compared of 3DCP that will enable the use of be dismantled and reused in
to subtractive fabrication methods or much lower-strength, less-polluting other locations. Its funicular
casting. printable materials. design ensures the 3DCP
Striatus follows masonry structural
logic on two levels. As a whole, the bridge
behaves as a series of leaning unreinforced
voussoir arches, with discretisations
orthogonal to the dominant flow of
compressive forces, following the same
structural principles as arched Roman
bridges in stone. Locally, on the level of
the voussoir, the 3DCP layers behave as
traditional brick masonry evident in the
inclined rows of bricks within Nubian or
Mexican vaulting.

Circular by design
Circular by design, Striatus places
material only where needed, significantly
reducing its environmental footprint.
Built without reinforcement and using
dry assembly without binders, Striatus can
be installed, dismantled, reassembled and
repurposed repeatedly; demonstrating

dw • Issue 247 19