Megaprojects
frequently face cost overruns and schedule delays, a pattern known as the iron
law of megaprojects, which persists partly because traditional determinis tic
or probabilistic planning methods are inadequate for managing deep uncertainty.
This form of uncertainty arises when the probability, timing, or impact of key
events cannot be reliably estimated, often leading to unrealistic schedules and
ineffective risk responses. This study investigates the question: How can
Exploratory Modelling and Analysis and Dynamic Adaptive Policy Pathways be
applied to improve schedule robustness in infrastructure construction
projects? The research focuses on the Schiphol bridge reconstruction, which is
part of the Veenix A9 BaHo project and is conducted in collaboration with Count
& Cooper. A Discrete Event Simulation (DES) model is built in SimPy and
structured using a task dependency graph de rived from the project’s original
schedule via NetworkX. The model is sampled 10,000 times under baseline
conditions using Latin Hypercube Sampling. In scenario discovery, Patient Rule
Induction Method (PRIM) is used in combination with a scaling function
identifying six high-impact scenarios, which serve both as inputs for robust policy
search and as Adaptation Tipping Points (ATP) for the Dynamic Adaptive Policy
Pathways (DAPP) schedule. Robust mitigation strategies are derived using a
Multi-Objective Evolutionary Algorithm under the Multi-Objective Robust Decision
Making framework, with a second PRIM experiment selecting four final robust policies.
These policies correspond to at least one of the high-impact scenarios and form
the backbone of a conditional DAPP schedule. The DAPP schedule is evaluated
against a static baseline using 5,000 DES simulations with identical
uncertainty sampling. In 20 comparative runs, it reduced project duration by an
average of 67 days and cost by approximately e97.5 million on the entire
project schedule. All three robust policies include the measures new design,
overtime labour, and electric machinery, suggesting that a focused subset of
actions can improve resilience even when the future is highly uncertain. Unlike
prior Decision Making under Deep Uncertainty (DMDU) applications, which often
focus on long-term or high-level strategic planning, this study embeds adaptive
logic within a highly granular, task-level construction schedule based on real
project data. This approach raises methodological challenges in how adaptation
tipping points are defined, triggered, and monitored within network-based
simulation. The findings demonstrate not only the feasibility of combining
Exploratory Modelling and Analysis (EMA) and DAPP in operational construction
settings but also the need for further research into real-time scenario recognition
and policy switching mechanisms under uncertainty.