Asynchronous Monitoring-Induced Deviation in Hydraulic Support Peak Estimation and Its Sensitivity to Synchronization and Sampling Resolution: A Case Study of a Solid Backfilling Working Face

Hydraulic-support pressure monitoring is widely used for mining-pressure interpretation and roof-weighting event statistics, but asynchronous records, incomplete spatial coverage and low-frequency instantaneous sampling can change the engineering quantity represented by a cycle peak. This study audits a continuous three-month pressure dataset from a large-height solid backfilling working face. The stored asynchronous available-section peak was reconstructed; synchronized face-mean, maximum section-mean and maximum support peaks were calculated on an exact 3 min grid; and multi-phase down-sampling was evaluated at 15, 30 and 60 min relative to the field high-frequency reference. The stored peak was determined from only one valid monitoring section in 240 of 255 cycles and exceeded the synchronized average pressure peak of the three monitored sections by 19.7 MPa on average, with weak overlap between their statistical roof-weighting labels. Regional and support-level synchronized indicators additionally identified local high-resistance responses that were not classified by the face-mean indicator under their respective thresholds. At 60 min, the mean retained-event rate across sampling phases was 0.484 relative to the field reference. Filling-advance ledgers and roadway-stress records showed exploratory associations with a restricted subset of joint events after correction for multiple testing. The results establish reporting requirements for peak definition, synchronization completeness, sampling resolution and engineering use before support-pressure peaks are used for event statistics or prediction.