Rock mass acoustic emission technology is making use of rock mass stress deformation and failure itself after emit sound waves and microseismic monitoring technology method of engineering rock mass stability. Rock mass acoustic emission and seismic phenomenon is discovered by American l. abbott and W.L. duvall in the late 1930 s.
At present, countries around the world gradually regard acoustic emission and micro seismic technology as a means of monitoring and early warning, to ensure the safety of underground engineering and mine production.
Lots of domestic and foreign scientific researches prove that rock mass will continue for a period of time to release the energy savings in the form of sound before destruction and this intensity of energy release, instability and change, as the structure approaches each acoustic emission and microseismic contain rich information of rock mass internal state change, received signal processing and analysis, can be used as the basis for evaluation of rock mass stability. , therefore, can make use of acoustic emission of rock mass and the feature of microseismic monitoring to the stability of the rock mass, so as to forecast rock landslides, roof caving, help, such as landslide and rock burst pressure phenomenon. Laboratory research shows that when the increase load of rock specimen, can be observed in specimens in destroying the seismic frequency and acoustic emission prior to a sharp increase in almost all of the rocks when the load added to 60% of its breaking strength, acoustic emission and the seismic phenomenon will appear, even if some rock load to 20% of its breaking strength, can also occur the phenomenon.
Rock acoustic emission instrument of PXAE series monitor the changing speed of the rock’s state by monitoring event rate and capacity, so as to evaluate and warn the rock mass structure stability.
PXAE02 type intelligent all_weather rock mass acoustic emission monitoring is the upgrade model of PXAE - 01. In PXAE - 01 original function increases the SD card storage, RS485 real_time data transmission over a long distance (part of the high_end version), online upgrade firmware, monitoring parameters can be defined (part of the high_end version) and other functions.
Technical parameters and features of PXAE02:
-
The microprocessor automatic operation real-time display and store the typical acoustic emission parameter
-
High integration small size host is only 98 volume (width) x 40 (high) x 157 mm (deep)
-
Waterproof ABS engineering plastics shell light in weight
-
Watertight enclosure waterproof grade IP66 instrument can be placed in the wild
-
Mixer adopts USB2.0 high-speed upgrade interface users can download the software free upgrade to the latest version of the software
-
Large capacity of 4 g SD flash card can store 10-12 consecutive months of data
-
Equipped with 4000 mAH lithium ion rechargeable batteries and low power design all-weather monitoring for 1 to 2 months can be conducted.
-
Monitoring mode sampling time sampling interval is adjustable
-
Mixer acoustic emission events defined threshold can be set according to the conditions in the field
-
Large pieces instrument panel LCD real-time display the current monitoring data and a blue backlight convenient for operation at night
-
Mixer acoustic emission monitoring data for open text format can be directly open the can be imported into Excel spreadsheet
-
Instrument automatically boot self-inspection and is equipped with the reset button may restore to factory equipment status at any time
-
Pieces can be more instrument of monitoring system for the overall monitoring of the structure
-
Random configuration PDA can read data at the scene
-
Pieces with the capacity of 4 g SD card convenient data into the computer for statistical analysis
-
Mixer sensor resonance frequency of 1 KHZ
-
Mixer sensor sensitivity is up to 90 mv/g
-
Combined with low noise programmable gain amplifier circuit the sensor monitoring scope diameter up to 100 meters
-
Sensor adopts stainless steel waterproof structure easy to sat on a rock or concrete structures
-
Adopted high drive ability of amplification circuit the sensor cable can be up to 100 meters
-
Mixer instrument equipped with RS485 communication interface data (part of high-end version) which can realize long-distance data transmission