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Working towards infrastructural standardization standardizing the overpass structural design process using vsm-analysis, and a first step into tool conceptualization.

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The civil engineering branch has been plagued by the high amount of failure costs for a long time
now, ~11% (USP-MC, 2013), resulting in very low margins across the market. A number of
solutions have been tried, LEAN engineering is the latest and probably most successful technique
used to decrease the failure costs. LEAN is already being used by a number of organizations in the
civil engineering branch, but it has been used mainly to improve management processes and
project schedules. As part of the LEAN philosophy, standardization has been used to create
standard documents and standard approaches for relatively simple processes. This research offers
an example how organizations can use LEAN and Value Stream Mapping to improve their more
complex processes to try and reduce the high failure costs of the organization by working towards
product standardization. The research focuses on the case study of an overpass but it is assumed
that found benefits and challenges are also applicable to other end products.
End product standardization, in the form of module based designing and with a standardized design
process, can offer a lot of improvements over the current structural design process. The literature
study and the field research show that a standardized design process will allow for better interfaces
between construction and design disciplines, it allows for increased productivity and effectiveness
in creating the design, it allows for quality optimization and a increased certainty of completion
date and costs. Product standardization allows for products to have a tried and tested track record,
predictable quality and performance, it allows for increased productivity and effectiveness in
building, and it allows a reduction of waste. There are, however, also some challenges for starting
with process- and product standardization in the civil engineering branch. The civil engineering
branch is generally slow to change and change is hard-fought. An implementation plan has been
created to help with this issue. It is also important for civil engineering products, and in this case an
overpass, to remain flexible enough so that a standard product can be used in multiple projects. To
this end it has been conceptualized that a module-based design best fits the need for
standardization whilst still being flexible enough.
Despite the challenges, the use of process- and product standardization might not be only an option.
Even though it does not fit inside the scope of this research project, it is abundantly clear that
standardization of components is very helpful in moving towards a circular economy, reducing
material costs and waste by re-use, and overall being more durable in the entire construction
process. The linear production model leads to unnecessary resource losses in several ways: waste
in the production chain, end-of-life waste, energy consumption, and erosion of ecosystem services.
A linear model is heavily depending on the global commodity stock (Verberne, 2016).
Standardization offers a chance to optimize design and construction of components, increasing the
quality, decreasing waste, and thus moving towards more durable and sustainable buildings and
infrastructure.
By using the LEAN manufacturing technique Value Stream Mapping and translating the technique
to the civil engineering branch, the design process of the contractor has been analyzed. This
analysis showed a lot of room for improvement, mainly in the large amount of activities that have
been classified as necessary waste and the amount of waste hidden in the process. To try and solve
the problems of the current design process of an overpass, an improved state design process has
been proposed which includes an automated overpass design tool. This improved design process is
projected to reduce the overall total lead time of the design process by 18.2%. The ratio value
adding – necessary waste activities swings 23,3% and 16,42% (respectively for the client and the
construction team) towards more time spent on value adding activities.
To implement the improved state design process, an implementation plan has been developed
which can be found in Appendix 4. In it, a series of steps based on the Golden Circle Model of Simon
Sinek has been proposed. This implementation process also utilizes Whole Scale Change theory
opposed to more common change management theories. Whole Scale Change theory is deemed
more suitable because it offers a wide approach to engage all stakeholders in the process of change.
If the contractor wants this initiative to succeed, it is imperative that there is a sufficient base
among employees, even more so if the contractor wants to expand the modular approach from only
the design phase to the procurement and realization phases as well (which they should because it
will only increase the amount of advantages the approach brings to the table). Whole Scale Change
will aid to create a sufficient base by involving stakeholders in an early stage.
End product standardization should be able to fit in the current market and contracts as long as the
contracts allow sufficient design freedom and the clients are willing to void or change a few
requirements to allow for the standardized end product. Talks with Rijkswaterstaat indicate that it
is prepared to meet these conditions as long as contractors can prove the extra value standardized
end products bring. It is up to the contractor to ensure enough variation range in the modules to
make sure that the standard product is no 1-trick pony. It is also advisable for contractors to work
together with an architect to design esthetic modules (for instance for the edge elements of a
overpass) so that the tender meets the esthetic requirements of the client.
The improved design process introduces an overpass design tool which is conceptualized to
provide a first step into the tools development. The tool offers a second level of standardization;
standardizing the structural design process is the first level of standardization, standardizing
certain variables within those calculations via the use of modules is the second level. The purpose
of the automated overpass design tool will be to benefit from both levels of standardization; By
using the tool, the overpass structural design process can be completed more efficiently meaning
that more valuable time can be spend on ”specials”, and it allows for the use of modules which
offers the possibility to benefit from the use of standard products. The system breakdown structure
of the overpass is used to explain the composition of the overpass and to choose a section to go into
more detail with. For the chosen scope, a BPMN diagram (business process model and notation)
will be used to map the transfer of data and to create the needed exchange requirement which will
help setting up a data structure for the structural design tool. The BPMN and the derivative data
structure will help the contractor in ensuring that all the needed variables for the tool have the
required data to execute the calculations.

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