Reference-Data Integrity and Statistical Monitoring for Digital Ready-Mixed Concrete Quantity Control

Small contractors need reliable digital workflows to detect excess material consumption before reference budgets are exhausted. However, digital delivery records alone cannot ensure effective quantity control when reference quantities contain errors or monitoring rules detect deviations too late. This study evaluates a no-code digital workflow implemented in a 52-dwelling housing project delivered by an SME contractor in Concepción, Chile. Following a Design Science Research approach, the evaluation combines capture-schema assessment, arithmetic verification, and statistical modeling. The structured capture workflow was deployed on site, the reference-data audit was applied to the project’s own budget records, and the monitoring results are design-time simulations rather than field measurements. No delivery-level dataset from the deployment period was available for analysis, so no record-completeness, duplication, or dispatch-note reconciliation rate is reported. Three of the four concrete categories were internally consistent within a 0.26 m3 rounding tolerance. G20 exhibited a 27.02 m3 discrepancy, equivalent to 2.81% of its recomputed budget and consistent with a digit transposition, which reduced the effective budget-exhaustion threshold to 97.19% of the recomputed reference. In a simulated scenario with a 10% excess consumption beginning at dwelling 10, the threshold rule signaled at dwelling 49 for G20, whereas an upper one-sided CUSUM signaled at dwelling 16 and a progress-adjusted cumulative deviation rule calibrated to the same false-alarm probability signaled at dwelling 19. Across categories, the summed median excess at detection was 154.5 m3 for the threshold rule and 23.8 m3 for CUSUM, representing simulated exposure rather than realized savings. Under known-parameter calibration, the CUSUM achieved approximately 80% detection probability for a sustained 0.46-standard-deviation shift over the 52-observation project horizon. The findings indicate that effective digital quantity control under the resource constraints of a small contractor requires three complementary conditions: traceable delivery records, verified reference quantities, and statistical monitoring calibrated to project duration and parameter uncertainty.