Our electromagnetic shock source (ESS10000) has been successfully developed and officially put into use. It makes the tunnel advance geological prediction have more choices other than artificial source such as hammer blow and electric spark. Compared with explosive source, ESS10000 avoids the security risks brought by explosives, complex management procedures and construction problems, it could be stimulated several times and no bad track risk. Compared with hammer blow, ESS10000 has higher impact energy and higher signal-to-noise ratio of reflected wave. Compared with the electric spark source, ESS10000 has lower voltage and higher safety and reliability in wet tunnel environment. Under the same observation system conditions and the surrounding rock grade is Class III, the prediction distance of ESS10000 reaches more than 100 m, which is close to the explosive source. ESS10000 uses wireless positioning, wireless trigger, wireless control and other advanced technology, and has simple and convenient operation. Used together with TETSP-2 semis advance prediction system, ESS10000 has lower construction cost, less time, little impact to the construction schedule.

Fig1. Electromagnetic shock source (ESS10000)

Fig2. work diagram of ESS10000

The electromagnetic shock source system (ESS10000) is composed of an energy storage main control box (ESS10000-EC) and an electromagnetic impact hammer (ESS10000-S).
 
Size And Weight: energy storage main control box (360*265*290mm; 22kg), electromagnetic impact hammer (∅220*1300 mm; 26kg)
 
Drive Power Supply: built-in, single full charge could be used for more than 500 times 
Single Impact Energy: ≥1200J 
Effective detection depth of tunnel advance prediction: ≥100m
Band width of excitation signal: 0.1-1200Hz
Control mode: panel operation/wireless remote control operation
Mobile construction mode: portable + portable/two-braces
Synchronous trigger mode: synchronous trigger switch (no drilling, hand-held press) + wired/wireless transmission
Energy exchange mode: direct coupling (no drilling, micro damage)
Average single-point construction time: ≤10s.