掺加碳纤维的Fe_(2)O_(3)功能集料电磁防护混凝土

Electromagnetic Protective Concrete with Fe_(2)O_(3) Functional Aggregate Mixed with Carbon Fiber

利用滚制成型法制备Fe_(2)O_(3)功能陶粒,并用作粗集料,在水泥石中掺加碳纤维吸波剂制备得到新型电磁防护混凝土。研究了功能陶粒的物相、形貌和相对电磁参数,采用弓形法测试对比了Fe_(2)O_(3)功能集料混凝土和普通碎石混凝土的吸波性能,分析了碳纤维掺量和匹配层对Fe_(2)O_(3)功能集料混凝土电磁吸波性能的影响。结果表明:在8~18 GHz,Fe_(2)O_(3)功能集料混凝土的反射率明显优于普通碎石混凝土,加入体积分数0.2%的碳纤维能在Ku波段提高混凝土的吸波性能,但碳纤维的掺入也易使Fe_(2)O_(3)功能集料混凝土与自由空间的阻抗匹配变差,发生强电磁反射;添加10 mm厚匹配层后,混凝土结构的吸波性能改善显著,碳纤维体积分数为0.6%的双层结构Fe_(2)O_(3)功能集料混凝土最小反射率为-13.48 dB。同时,对制得的电磁防护混凝土的抗压性能进行测试,碳纤维体积分数为0.2%时,混凝土抗压强度最佳,28 d可达47.2 MPa。

Fe_(2)O_(3) functional ceramsite was prepared by rolling forming method, and then used as coarse aggregate to prepare the new electromagnetic protective concrete with a certain proportion of carbon fiber wave absorbent. The phase, morphology and relative electromagnetic parameters of functional ceramsite were investigated. The electromaganic wave absorbing properties of FeOfunctional aggregate concrete and common crushed stone concrete were measured and compared by the arch method. The effects of carbon fiber content and matching layer on the electromagnetic wave absorbing properties of FeOfunctional aggregate concrete were analyzed. The results show that the reflectivity of Fe_(2)O_(3) functional aggregate concrete is obviously better than that of common crushed stone concrete at 8~18 GHz. The absorption performance of concrete with volume fraction 0.2% carbon fiber in Ku band with volume fraction can be improved, but the addition of carbon fiber also tends to make the impedance matching between Fe_(2)O_(3) aggregate concrete and free space worse, and the strong electromagnetic reflection occurs. When the 10 mm thick matching layer is added, the absorbing performance of concrete structure is improved significantly. Double-layer Fe_(2)O_(3) functional aggregate concrete with volume fraction 0.6% carbon fiber has the minimum reflection loss of-13.48dB. At the same time, the compressive properties of the electromagnetic protective concrete are measured.When the volume fraction of carbon fiber is 0.2%, the compressive strength of the concrete is the best,which could reach 47.2 MPa after 28 days.