This thesis presents a prestressed and modular design for relieving platforms in deep-sea
quay walls that reduces concrete usage, thereby lowering carbon emissions, and enabling
future upgrades.

About 37% of the world’s CO2 emissions come from the built environment, making it
a significant contributor. To address these issues the Port of Rotterdam has set sustainability
goals, which include becoming climate neutral by the year 2050 and reducing CO2
emissions from material consumption by 25% by the year 2030. This thesis has contributed
to these goals by designing and optimizing a modular prestressed relieving platform for
deep-sea quay walls, that has reduced material usage and carbon emissions. The focus
lied on the relieving platform floor, creating a flexible and upgradable quay wall structure.
The application of post-tensioning has been investigated in the design of the relieving
platform. Several different prestressing variants have been designed, parameterized and
later optimized. In addition a parametric cross-section optimization has been performed
by creating an opening around the neutral axis, that further reduced the concrete usage
in the floor. A final design of the relieving platform floor using a total prestressing tendon
area of 4.500 mm2 per meter resulted in a minimum cross-section height of 890 mm and
an embodied carbon reduction of 20%.

A prefabricated, modular solution has been designed that enables the upgrade of a
quay wall structure by allowing for the relieving platform floor to be added at a later
stage. The building sequence has been designed with a focus on efficiency. The modular
design benefited from the weight reduction of 50% that resulted from the application of
prestressing. Three main connections have been designed, for which several solutions have
been proposed, namely: the module-to-module connection, the module-to-wall connection
and the module-to-foundation pile connection. Particular attention is given to the placement
of the prestressing anchor on the water side of the relieving platform, for which two
alternative solutions have been proposed.

The findings of this thesis show that prestressing can play an important role in creating
lightweight, lower-carbon and modular relieving platforms for deep-sea quay walls. It has
allowed for a significant material reduction, crack control and weight reduction, facilitating
the prefabrication of the floor. This design offers a flexible, upgradeable and lightweight
alternative to traditional the relieving platform design.