Methods and Pilot Protocol for Seam-Level Acceleration Detection in EPC Megaprojects: A Second-Order Early-Warning Operator for Structural Drift

Megaprojects in engineering, procurement, and construction (EPC) routinely experience cost and schedule overruns, with comprehensive studies showing that approximately 91.5% miss cost, schedule, or benefit targets and fewer than 1% achieve success across all three dimensions. While initial bidding and estimation inaccuracies contribute significantly, execution-phase drift at operational seams—contractor interfaces, schedule float consumption, and quality/rework cycles—often amplifies problems and remains undetected by aggregate milestone or earned-value metrics until cascades are underway. This preprint presents a focused validation protocol for a purpose-built acceleration statistic: a second-order detector that identifies accelerating structural drift by computing a rolling trend slope (velocity) followed by the change in that slope over a subsequent window, calibrated against quiet-period baselines. Prior testing on the Kundur two-area power system demonstrated noise-robust lead-time advantages over common rate or threshold detectors in high-frequency oscillatory environments. A complementary diagnostic test on real megaproject data (Plant Vogtle 3&4) yielded an honest null at coarse (semi-annual) granularity, indicating that the structured high-frequency noise the operator is engineered to resist is not prominent at that scale. The proposed 4-week archive-based pilot tests one specific, falsifiable claim on real EPC telemetry at operational seam resolution (weekly/monthly contractor-level updates): Does the acceleration operator flag accelerating drift in schedule, contractor coupling, or rework earlier than the project’s conventional tracking? Primary outcomes are limited to detection-lag findings (timestamp comparison with effect size). Downstream benefits are explicitly labeled exploratory. The protocol includes a frozen operator specification, full disclosure of all test runs (including nulls), governance safeguards for sensitive contractor-coupling analysis, and explicit interpretive boundaries. Key methodological contributions include:- Formal mathematical definition of the acceleration statistic with practical heuristic window ranges for weekly and daily telemetry.- Explicit handling of human reporting batching and inertia common in EPC environments.- Two conceptual figures illustrating the pipeline and lead-time advantage.- Clear scoping that the “4-week” designation refers to research execution time on multi-month or multi-year historical archives. This diagnostic pilot is designed for transparency and reproducibility. A positive result would establish earlier detection at the granularity where EPC teams manage risk daily, without overclaiming cost or schedule protection. The work advances upstream coherence measurement (UCMS/SCFL framework) as a practical tool for megaproject resilience and contributes to the broader evidence base on seam-level early-warning systems in capital project delivery. Related UCMS/SCFL materials are available via the author’s Zenodo record and ORCID.