Deconstructing the Micro-Scheduling Dictatorship: A Stochastic-Possibilistic Framework for On-Site Construction

 On-site construction production languishes in a state of chronic unreliability, as the rigid, deterministic master schedules derived from Critical Path Method (CPM) logic continually fracture upon contact with reality. This article argues that the failure is ontological: a construction project is not a deterministic system prone to probabilistic variance, but a fundamentally non-deterministic system where possibility, not probability, must be the governing logic. We introduce the "Stochastic-Possibilistic Framework," which replaces the task-as-commitment with the "task-as-option." In this model, detailed micro-schedules are not a single forward prediction but a dynamically branching tree of conditional work packages. A new role, the "Possibility Engineer," uses a real-time combinatorial optimization engine to select which branch to activate only when a "critical enabler"—such as a confirmed material delivery or a completed inspection—is instantiated. The abstract develops a new metric, "Scheduled Flow Reliability," which measures how often the system can produce a feasible 72-hour look-ahead plan from the current state, rather than measuring adherence to an infeasible original baseline. We show through simulation that this approach decouples long-term milestones from short-term execution, absorbing the inherent non-linearity of building without sacrificing the predictability of the final completion date.