Geological disasters, such as landslides, mudslides, earthquakes, etc., often occur suddenly and bring heavy blows to human society. These disasters not only consume lives and destroy homes, but also cause serious damage to infrastructure and hinder socio-economic development. In order to effectively prevent geological disasters and reduce their losses, accurate monitoring is crucial, and sensors play an irreplaceable key role in it.
In the field of landslide monitoring, sensors play the role of "scouts". The occurrence of landslides is often related to various factors, including rainfall, rock and soil characteristics, topography, and landforms. Sensors can monitor these factors in real-time and provide critical data for predicting landslides. Installing displacement sensors in landslide prone areas can closely monitor displacement changes on the surface and inside of the mountain. Once there is an abnormal increase in displacement data, it may indicate that a landslide is about to occur. Pore water pressure sensors can real-time monitor changes in groundwater level and pore water pressure. Due to the rise in water level and pore water pressure, the shear strength of rock and soil mass will be reduced, increasing the risk of landslides. Through the collaborative work of these sensors, early signs of landslides can be detected in a timely manner, buying valuable time for personnel evacuation and the implementation of preventive measures.
The monitoring of debris flows also relies on sensors. The formation of debris flows is closely related to heavy rainfall, abundant loose solid materials, and specific terrain conditions. Rainfall sensors are at the forefront of debris flow monitoring, providing important basis for determining the likelihood of debris flow occurrence by accurately measuring rainfall and rainfall intensity. In debris flow gullies, flow velocity sensors and mud level sensors can monitor water flow velocity and mud level height in real time. Once the data exceeds the warning threshold, an alarm can be issued in a timely manner. In addition, by using sensors such as geological radar, it is possible to monitor the source conditions and potential landslide scale on both sides of the debris flow channel, and predict the scale and degree of harm of the debris flow in advance.
Earthquake monitoring is a major global issue, in which sensors play a central role. Seismic wave sensors, such as accelerometers and velocity sensors, can keenly capture the propagation of seismic waves. By analyzing seismic waves, scientists can determine key parameters such as earthquake magnitude, focal depth, and epicenter location. In earthquake prone areas, building a dense sensor network can achieve real-time and comprehensive monitoring of earthquake activity. The early warning system uses sensors to quickly capture seismic longitudinal waves (P-waves) and issue warnings to surrounding areas before the more destructive transverse waves (S-waves) arrive. Although the warning time may only be a few seconds to a few tens of seconds, this brief time is enough for people to take emergency measures such as stopping dangerous operations, hiding in safe areas, etc., greatly reducing casualties and property damage.
In addition to the common geological hazards mentioned above, sensors also play an important role in monitoring geological hazards such as ground subsidence and volcanic activity. In ground subsidence monitoring, by deploying GNSS (Global Navigation Satellite System) monitoring sensors, it is possible to accurately measure the vertical and horizontal displacement of the ground, detect ground subsidence phenomena in a timely manner, and analyze their development trends. For volcanic activity, temperature sensors and gas composition sensors can monitor temperature changes and gas emissions in the volcanic crater and surrounding areas, providing important clues for predicting volcanic eruptions.
Sensors are like sharp "outposts" in geological hazard monitoring, providing strong support for early warning and effective prevention and control of geological hazards with their diverse types and powerful functions. With the continuous advancement of technology, the accuracy, reliability, and intelligence level of sensors will continue to improve, playing a more important role in the field of geological hazard monitoring, and contributing greater strength to safeguarding human life and property safety and social stability and development.