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|Other Titles: ||Shielding effectiveness of conductive concrete for electromagnetic waves and radiation|
|Authors: ||高阜康;Kao, Fu-Kang|
段永定;Tuan, Alex Y.
|Keywords: ||導電混凝土;導電性材料;電磁波屏蔽;核輻射屏蔽;屏蔽效益;conductive concrete;Conductive material;Electromagnetic shielding;Radiation shielding;Shielding effectiveness|
|Issue Date: ||2016-01-22 15:01:14 (UTC+8)|
研究結果顯示：對於頻率範圍100KHz~8.5GHz之電磁波，添加鉛粉與碳纖維皆能提升電磁波屏蔽效益，其中又以碳纖維提升效果較為顯著；碳纖維添加量越多屏蔽效益越高，且電磁波頻率越高屏蔽效益越高。添加鉛粉可以提升試體對於電磁波遮罩性能，但添加鉛粉對提升屏蔽效益沒有碳纖維來得顯著，同時鉛粉會影響水泥混凝土之力學強度、砂漿的耐久性等，添加量越多影響越嚴重。另外，藉由電阻率之測試，可以發現電磁波遮蔽效果與電阻率和頻率都有關係；電阻率越小之試體，電磁波遮蔽性能越高，同時，隨著頻率的增加其遮罩性能也會越高，試體中S1.0G10CF0.9表現效果較佳，對於電磁波屏蔽是顯著的。最後，對於輻射γ射線的遮蔽性能來說，添加碳纖維之試體並沒有顯著的影響，其輻射遮蔽效果幾乎同於一般混凝土。反而添加鉛粉之試體添加10%後的鉛粉輻射屏蔽的衰減係數較一般混凝土高出13%，試體中以S1.0 G10 Pb10表現效果較佳，對於γ射線的屏蔽是顯著的，可有效的阻擋γ射線並提升遮罩性能。
This study is focused on the improvement of the “Shielding Effectiveness of Conductive Concrete”. By using the lead powder and carbon fiber to replaced the barium ferrite. In addition, the frequency range to be considered has been increased from 30MHz ~ 1.8GHz to 100KHz ~ 8.5GHz. The shielding effectiveness of electromagnetic waves have been tested. The addition of the lead powder and carbon fiber into the concrete mixtures and the effects of electromagnetic shielding were observed. The research results shows that the new mixture has better shielding effectiveness. Different proportions have been tried for electromagnetic shielding for γ radionuclides shielding test. Study the impact of lead powder and carbon fiber for radiation shielding of the two materials.
The result shows that add lead powder and carbon fiber can enhance the electromagnetic shielding effectiveness in the frequency range from 100KHz ~ 8.5GHz. The most significant effect is to add the carbon fiber. As more amount of the carbon fiber has been added, the higher shielding effectiveness has been achieved. Also, the higher the frequency, the higher the electromagnetic shielding effectiveness has been achieved. Add lead powder can improve the performance of the electromagnetic shielding, but adding lead powder without carbon fiber is more effective. At the same time lead powder will affect the mechanical strength of the concrete, durability, the more serious impact on the added amount. Further, with resistivity testing, the electromagnetic shielding effect was found that the resistivity and frequency are related. The smaller resistivity, the higher electromagnetic shielding performance, and with increasing frequency, the shielding performance will be higher. Finally, add the carbon fiber has no significant effect for γ rays radiation shielding, same as radiation shielding of general concrete. Instead, after the addition of 10% lead powder radiation shielding attenuation coefficient 13% higher than normal concrete. Lead powder for γ-ray shielding is phenomenal, can effectively block the γ-ray and improve performance.
|Appears in Collections:||[土木工程學系暨研究所] 學位論文|
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