• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.11
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• pp.1197-1200
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• 2014

Two test standards to be applied for evaluating shielding effectiveness of HEMP protection facilities, MIL-STD-188-125-1 and IEEE std. 299, provide different test results in spite of the same facility. In particular, at the frequency range of 10 kHz~20 MHz, it is confirmed that the test results by the IEEE Std. 299 are about 20~30 dB lower than the evaluated results by MIL-STD-188-125-1. These results are due to the different measurement conditions specified in the two test standards. Therefore, IEEE Std. 299 can be applied for the shortening of test distance, but the required SE performance based on MIL-STD-188-125-1 must be modified.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.50-51
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• 2018

In this study, it evaluate the electromagnetic pulse shielding performance of amorphous metallic fiber reinforced cement composite with other steel fiber reinforced cement composite. Hooked-ended steel fiber, smooth steel fiber and amorphous metallic fiber were reinforced 2.0 vol.% in cement composites respectively. The electromagnetic pulse shielding performance was evaluated by MIL-STD-188-125-1. As a result, shielding performance of amorphous metallic fiber reinforced cement composite was higher than Hooked-ended and smooth steel fiber reinforced cement composites. In addition, the relationship between the electrical conductivity and the electromagnetic pulse shielding performance of the cement composite was confirmed.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.2
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• pp.151-161
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• 2019

In this study, to evaluate the High Altitude Electromagnetic Pulse(HEMP) protection performance of UHPC/CNT composites by the content of Carbon nanotubes(CNTs), Electromagnetic Shielding Effectiveness(SE) test was performed based on MIL-STD-188-125-1. And the results were verified by applying the Antenna theory. In the case of UHPC with a thickness of 200 mm mixed with 1 % CNT of cement weight, the SE was 28.98 dB at 10 kHz and 45.94 dB at 1 GHz. Then the Scabbing limit thickness for bullet proof was computed based on the result of compressive strength test which was 170 MPa, and it was examined whether it satisfied the HEMP protection criteria. As a result, the required HEMP shielding criteria were satisfied in all frequency ranges as well as the scabbing limit thickness was reduced by up to 43 % compared with that of ordinary concrete.

• Journal of the Korean Recycled Construction Resources Institute
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• v.9 no.4
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• pp.478-482
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• 2021

In this paper, methods for manufacturing shielding concrete by recycling steelmaking slag discarded as industrial waste and measuring the shielding effectiveness of the shielding concrete were studied. By comparing the result of shielding effectiveness measurement of this concrete block with shielding effectiveness measurement of the structure constructed with this concrete, the measurement system for measuring shielding effectiveness of the concrete block was verified. The size of the concrete stru ctu re is 2.9 × 2.9 × 3.4m and the concrete block is 0.3 × 0.3 × 0.2m. The frequ ency band u sed for mesu rement is 600MHz - 2GHz, the types of concrete u sed to measu re the shielding effectiveness are general concrete and concrete containing electric arc furnace oxidizing slag. In the case of the concrete structure, reinforcing rebars are installed at intervals of 15cm for stru ctu ral safety, as the frequ ency increase, the electromagnetic wave properties of rebars gradu ally decreased, there was a slight difference in the measurement results. In conclusion, the measurement result of shielding effectiveness of the concrete block is similar to the result of the concrete structure. It is thought that it can be sufficiently utilized for electromagnetic wave engineering design, and the concrete shielding effectiveness measurement system using standard specimens was verified.

• Journal of the Korea Institute of Building Construction
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• v.13 no.6
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• pp.579-584
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• 2013

The stable fueling and water supply should be prerequisites to guarantee the operational sustainment of military command post. Meanwhile, in terms of the operational sustainment, it is verified that the current wave-guided below cutoff (WBC) system cannot satisfy the requirement of control associated with water supply and fueling within the command post. In this study, as the dielectric substance can block electromagnetic pulse (EMP), it was tried to identify the shielding effectiveness of the multi WBCs filled with water and diesel for attenuating the EMP effect using experiment based on the MIL STD 188-125-1. According to the experimental results, used water in the experiment show the shielding effectiveness from around 640 MHz frequency because of minerals contained in the water. Furthermore, it was noted that EMP attenuating strength of the WBC filled with diesel was enlarged from around 1,680 MHz frequency. Resultingly, it could be concluded that it is enough to supply stable water and diesel through the multi WBC to block EMP within the military command post for guaranteeing the military operations sustainment.