China's mineral resources are gradually entering the stage of deep well mining, and ground pressure disasters such as roof caving, collapse, rockburst, etc. induced by high stress and rock pressure in the deep have seriously affected the safety production of mines. According to the latest statistics released by the National Bureau of Mining Safety Supervision, there were 434 mining accidents and 573 deaths in China in 2020. Therefore, mine safety monitoring has significant social demand and practical value.

With the development of high-precision and high sampling rate sensors and the rapid advancement of computer technology, high-precision positioning and real-time monitoring of mine microseismic have become possible. With the continuous improvement of microseismic positioning technology, microseismic monitoringMeasurement has been able to achieve spatiotemporal positioning and stability assessment of mining hazards, and has been widely used in safety monitoring of deep well mines in recent years. It has become a highly recognized method for monitoring and early warning of ground pressure disasters in the industry.

As a transducer unit for collecting microseismic waveform signals, microseismic sensors convert the measured signals from vibration signals to electrical signals that can be recognized by microseismic monitoring systems. Due to the strong energy of blasting vibration signals in the frequency band of 375-500Hz, while the energy of mining rock mass rupture signals (microseismic) is mainly concentrated in the low-frequency band of 0-250Hz, monitoring the low-frequency components can better record the mining microseismic signals, understand the areas of rock rupture in the mining area, and be beneficial for safe mining.

The characteristics of microseismic signals in mines are wide frequency range and weak signal-to-noise ratio, which makes signal processing more difficult. Background noise, power frequency interference, artificial activities and other signals in mining sites can seriously interfere with the effective microseismic event waveform information, greatly reducing the signal-to-noise ratio of microseismic waveforms and increasing the difficulty and reliability of picking up P-waves when they arrive.

The mining microseismic monitoring system monitors a massive number of microseismic events every day. Although it can be intuitively picked up by data processors manually, manually picking up waveforms is susceptible to the experience and subjectivity of data processors, and is time-consuming and labor-intensive.

Therefore, the denoising of weak signals in mining microseismicity and automatic picking up at the time of arrival are of great significance for real-time microseismic monitoring technology.

Senther Technology earthquake monitoring dedicated sensor 374A

The 374A series accelerometer is a specially designed accelerometer for detecting ultra-low frequency and low-frequency vibrations in large buildings, infrastructure, and earthquake monitoring applications; Its characteristic is to output a low-noise and high amplitude signal through a sensing mechanism, with excellent measurement resolution.Both ceramic crystals and quartz crystals can be used in the design of seismic acceleration sensors, with ceramic crystals having higher output efficiency than quartz crystals. The 374A product uses ceramic crystals as sensitive components, which provides better signal quality and low-frequency response characteristics. It also has a built-in low-noise signal modulator, resulting in high resolution. In order to achieve the best measurement results, seismic acceleration sensors are usually used together with gain amplifiers and power signal modulators.This accelerometer adopts laser welding to firmly weld the stainless steel shell and military type joint together; The shell isolation, internal shielding, external environment (including RF, EMI, ESD, and overload), and the impact of misoperation on the product are completely controllable, ensuring excellent repeatability and long-term stability of the product.The 374A earthquake sensor is mainly divided into two models, 374A-0.25 and 374A-0.5, based on their different output sensitivities. The ultra-high sensitivity version of the 374A-0.25 earthquake sensor features ultra-high sensitivity, ultra-low body noise, ultra-low frequency response, and other performance designs. It is particularly suitable for applications such as earthquake pulsation wave perception, bridge micro acceleration vibration signal perception, building swing acceleration perception, acceleration perception monitoring during tower shaking, micro deformation acceleration perception of dam bodies under water flow impact, spectral signal analysis perception during shock wave feedback during geological exploration, ocean seabed pulsation wave signal perception, underwater tunnel micro vibration information collection, high-speed railway tunnel micro vibration perception, and subway tunnel micro vibration perception.

characteristic:

·Ultra-low frequency response

·Top out connector

·High sensitivity

·Metal welding seal

·Shell isolation

·EMI/RFI shielding

Application:

·Building vibration monitoring

·Earthquake detection

·Bridge monitoring

·Research on Infrastructure Vibration

·Structural testing