Precision calibration and suitability analysis of piezoelectric rain gauges for complex scenarios in geological hazard monitoring

Rainfall, especially local concentrated heavy rainfall, is one of the major factors triggering sudden geological hazards such as landslides and debris flow. According to historical disaster statistics in China, locally short-term concentrated heavy rainfall is the primary triggering factor for debris flows, accounting for approximately 70% of the total number of landslides. Recent alterations in seasonal rainfall patterns, with accelerated spring floods and plum rain in southern China, as well as delayed autumn rain in the northern regions, have led to an increase in geological disasters, expanded risk-prone areas, and prolonged risk management periods. Therefore, conducting rainfall monitoring is of great significance for landslides and debris flow early warning and prediction. To ensure precise early warnings and predictions, the accuracy, sensitivity, stability, and scientifically grounded installation of rainfall monitoring equipment are prerequisites. This study, comparing two types of rain gauges-- tipping bucket and piezoelectric—in terms of measurement principles, technical specifications, installation methods, and operational maintenance, conducted both indoor simulated rainfall experiments and field tests within complex scenes. The results reveal that the piezoelectric rain gauge maintains an error range within 4%. These findings highlight that in the context of complex geological hazard monitoring scenarios, the piezoelectric rain gauge proves more suitable than the tipping bucket rain gauge, regardless of measurement range, accuracy, installation, or post-installation maintenance considerations