基于微波辐射计的建筑材料介电特性及含水量影响研究

doi:10.12068/j.issn.1005-3026.2025.20240034

摘要/Abstract

摘要：

为解决传统接触式点频法难以准确反映大尺寸样品整体介电特性的问题，采用微波介电测试系统，对常见建筑材料的介电特性进行研究.结果表明：极化能力是决定材料介电特性差异的关键因素.木材和塑料主要由弱极性的共价键构成，介电常数较低；橡胶和大理岩分别含有强极性的碳碳双键与离子键，介电常数偏高；砂岩、花岗岩和玻璃主要成分均为二氧化硅，但玻璃的非晶态结构影响了内部电荷分布和极化行为，导致介电常数较高.对于同种材料，含水量对介电常数的影响最显著，为进一步研究含水量对介电常数的影响，建立了渗透水含水量介电模型.结果表明：当木材含水量处于0~30%、砂岩含水量处于0~0.5%时，水分以结构水或吸附水形式存在，对介电常数影响较小；含水量上升后，水分子以自由水形式分布于样品孔隙内部，对介电常数影响显著；当岩石表面存在附着水时，介电常数会大幅增加.

关键词: 建筑材料, 介电常数, 微波辐射, 含水量, 介电模型

Abstract:

Traditional contact-based dot frequency methods fail to accurately characterize bulk dielectric properties of large-scale samples. Therefore， a microwave dielectric testing system was utilized to investigate the dielectric properties of common building materials. The results show that polarization capability is the primary determinant of dielectric property variations. Wood and plastics are mainly composed of weak polar covalent bonds with a low dielectric constant. Rubber and marble demonstrate elevated dielectric constants due to their strongly polar carbon-carbon double bonds and ionic bonds， respectively. Although sandstone， granite， and glass share silica as their primary constituent， the amorphous structure of glass modifies charge distribution and polarization behavior， yielding a higher dielectric constant. For the same material， water content constitutes the most significant factor governing dielectric properties. Therefore， the influence of water content on dielectric constant was further studied， and the dielectric model of water content in permeable water was established. The results show that when the water content of wood is 0~30% and that of sandstone is 0~0.5%， the water exists in the form of structural water or adsorbed water， which has little effect on the dielectric constant. After the water content increases， the water molecules are distributed in the pores of the sample in the form of free water， which has a significant effect on the dielectric constant. The presence of surface-attached water induces significant dielectric constant amplification in rock specimens.

Key words: building materials, dielectric constant, microwave radiation, water content, dielectric model

中图分类号:

P 237

朱安魁, 刘金生, 刘善军, 敖萌. 基于微波辐射计的建筑材料介电特性及含水量影响研究[J]. 东北大学学报（自然科学版）, 2025, 46(9): 126-134.

An-kui ZHU, Jin-sheng LIU, Shan-jun LIU, Meng AO. Study on Dielectric Properties and Influence of Water Content of Building Materials Based on Microwave Radiometer[J]. Journal of Northeastern University(Natural Science), 2025, 46(9): 126-134.

图/表 14

图1 微波介电测试系统示意图

Fig.1 Schematic diagram of microwave dielectric testing system

图2 “环境-样品-黑体”模型微波辐射传输示意图

Fig.2 Schematic diagram of microwave radiation transfer for “environment-sample-blackbody” model

图3 实验材料（a）—桐木；（b）—杉木；（c）—松木；（d）—塑料；（e）—橡胶；（f）—玻璃；（g）—砂岩；（h）—花岗岩；（i）—大理岩.

Fig.3 Experimental materials

表1 实验材料参数统计 (materials)

Table 1 Parameter statistics of experimental

实验样品	尺寸/cm（长×宽×厚）
桐木	50×50×1.5
杉木	40×40×1.5
松木	40×40×1.5
塑料	50×50×1.5
橡胶	50×50×0.5
玻璃	40×40×0.5
砂岩	30×30×2.0
花岗岩	25×25×2.0
大理岩	25×15×2.0

图4 干燥与附着水状态样品图（a）—花岗岩表面干燥状态；（b）—花岗岩表面附着水状态.

Fig.4 Sample diagrams of dry state and attached water state

图5 实验现场图（a）—白天实验现场图；（b）—夜间实验现场图.

Fig.5 Experimental site diagrams

表2 不同观测环境下介电常数实部反演结果

Table 2 Inversion results of real part of dielectric constant under different observation environments

环境	桐木	塑料	玻璃	花岗岩
白天	1.369 9	1.417 1	4.395 6	2.376 1
夜间	1.493 9	1.529 7	5.114 0	2.420 7

表3 介电常数反演结果

Table 3 Dielectric constant inversion results

实验样品	介电实部	介电虚部
松木	1.121 6	0.235 8
杉木	1.264 2	0.204 3
桐木	1.494 0	0.134 2
塑料	1.529 7	0.000 1
橡胶	3.902 9	0.075 0
玻璃	5.114 0	0.222 7
砂岩	1.617 3	0.500 5
花岗岩	2.332 0	0.036 3
大理岩	5.591 0	0.012 9

表4 桐木、杉木、松木和砂岩不同含水量下的介电常数 (contents)

Table 4 Dielectric constants of Paulownia wood, fir wood, pine wood and sandstone under different water

桐木		杉木		松木		砂岩
含水量/%	介电常数	含水量/%	介电常数	含水量/%	介电常数	含水量/%	介电常数
0	1.000 0	0	1.000 0	0	1.000 0	0	1.610 1
11.2	1.000 0	8.9	1.000 0	11.1	1.000 0	0.37	1.626 1
20.0	1.000 0	19.7	1.000 0	20.0	1.000 0	0.65	1.683 1
25.5	1.105 4	26.0	1.000 0	30.7	1.000 3	1.05	1.764 6
38.8	1.902 8	33.1	1.276 2	41.4	1.263 1	1.46	1.959 7
47.3	3.449 0	38.1	1.310 2	51.2	2.048 4	1.95	2.018 0
59.1	4.693 5	43.2	1.771 0	63.4	2.584 2	2.16	2.055 7
62.0	5.533 5	48.5	2.580 3	75.3	4.036 9	2.29	2.075 0
78.6	7.037 6	53.4	4.567 9	86.9	4.999 5	2.50	2.130 6
—	—	61.3	6.129 6	98.5	5.425 0	2.64	2.362 7
—	—	—	—	112.2	5.980 4	—	—

图6 不同含水量材料的介电常数（a）—木材介电常数；（b）—砂岩介电常数.

Fig.6 Dielectric constant of materials under different water contents

表5 不同状态介电常数反演结果 (at different water state)

Table 5 Inversion results for dielectric constant

岩石表面状态	花岗岩	大理岩
干燥状态	2.332 0	5.591 0
附着水状态	4.399 7	7.435 2

图7 含水量介电模型（a）—木材介电模型；（b）—砂岩介电模型.

Fig.7 Dielectric model of water content

图8 角反射器摆放图

Fig.8 Arrangement diagram of corner reflector

图9 角反射器识别结果（a）—干燥木板；（b）—浸水木板；（c）—“木板+铝板”组合.

Fig.9 Recognition results of corner reflectors

参考文献 30

[1]	Ulaby F T. Microwave response of vegetation［J］. Advances in Space Research， 1981， 1（10）： 55-70.
[2]	Protopopov O， Bulycheva N， Kolyasnikov V. Dielectric characteristics of pulverised Nazarovo brown coal［J］. Thermal Engineering （English Translation of Teploenergetika）， 1972， 19（1）： 120-122.
[3]	Roberts S， Von Hippel A. A new method for measuring dielectric constant and loss in the range of centimeter waves［J］. Journal of Applied Physics， 1946， 17（7）： 610-616.
[4]	Iglesias T P， Seoane A， Rivas J. A contribution to the measurement of permittivity with the short-circuited line method［J］. IEEE Transactions on Instrumentation and Measurement， 1994， 43（1）： 13-17.
[5]	杨长保，吴梦红，张晨曦，等. 岩石化学成分及复介电常数与光谱特征的关系探究［J］. 光谱学与光谱分析， 2016， 36（10）： 3103-3109.
	Yang Chang-bao， Wu Meng-hong， Zhang Chen-xi， et al. Relationship exploration of chemical content， complex dielectric constant and spectral features of rocks［J］. Spectroscopy and Spectral Analysis， 2016， 36（10）： 3103-3109.
[6]	Zhao D S， Rietveld G， Teunisse G M. A multistep approach for accurate permittivity measurements of liquids using a transmission line method［J］. IEEE Transactions on Instrumentation and Measurement， 2011， 60（7）： 2267-2274.
[7]	Li L， Chen X M， Ni L， et al. Evaluation of microwave dielectric properties of giant permittivity materials by a modified resonant cavity method［J］. Applied Physics Letters， 2007， 91（9）： 092906.
[8]	Shimizu T， Kojima S， Kogami Y. Accurate evaluation technique of complex permittivity for low-permittivity dielectric films using a cavity resonator method in 60 GHz band［J］. IEEE Transactions on Microwave Theory and Techniques， 2015， 63（1）： 279-286.
[9]	Mao W F， Wu L X， Qi Y. Impact of compressive stress on microwave dielectric properties of feldspar specimen［J］. IEEE Transactions on Geoscience and Remote Sensing， 2020， 58（2）：1398-1408.
[10]	Pereira V M， Hardt L G， Lima L S C， et al. Experimental characterization of borosilicate glasses fabricated from rice husk ash using the resonant cavity method［J］. Materials Science and Engineering： B， 2023， 287： 116138.
[11]	Parkhomenko M P， Kalenov D S， Fedoseev N A， et al. The improved resonator method for measuring the complex permittivity of materials［J］. Journal of Communications Technology and Electronics， 2017， 62（7）： 759-764.
[12]	Guo C， Liu R， Chen X L， et al. An ultra-wideband measurement method for the dielectric property of rocks［J］. IEEE Geoscience and Remote Sensing Letters， 2019， 16（6）： 874-878.
[13]	Xiong G， Meng Y F， Li J Z， et al. Precise measurements of the permittivity of microwave absorbing materials at microwave frequencies［J］. Journal of Materials Science（Materials in Electronics）， 2020， 31（12）： 9904-9910.
[14]	Thakur Y， Zhang T， Lacob C， et al. Enhancement of the dielectric response in polymer nanocomposites with low dielectric constant fillers［J］. Nanoscale， 2017， 9（31）： 10992-10997.
[15]	Tu S B， Jiang Q， Zhang X X， et al. Large dielectric constant enhancement in MXene percolative polymer composites［J］. ACS Nano， 2018， 12（4）： 3369-3377.
[16]	肖金凯. 矿物和岩石的介电性质研究及其遥感意义［J］. 环境遥感， 1988（2）： 135-146.
	Xiao Jin-kai. Dielectric properties of minerals and rocks and their application in remote sensing［J］. National Remote Sensing Bulletin， 1988（2）： 135-146.
[17]	Ulaby F T， Batlivala P P. Optimum radar parameters for mapping soil moisture［J］. IEEE Transactions on Geoscience Electronics， 1976， 14（2）： 81-93.
[18]	Oh Y， Sarabandi K， Ulaby F T. An empirical model and an inversion technique for radar scattering from bare soil surfaces［J］. IEEE Transactions on Geoscience and Remote Sensing， 1992， 30（2）： 370-381.
[19]	Fernandez-Galvez J. Errors in soil moisture content estimates induced by uncertainties in the effective soil dielectric constant［J］. International Journal of Remote Sensing， 2008， 29（11）： 3317-3323.
[20]	Lu Q， Liu K X， Zeng Z F， et al. Estimation of the soil water content using the early time signal of ground-penetrating radar in heterogeneous soil［J］. Remote Sensing， 2023， 15（12）： 3026.
[21]	张立振. 基于微波辐射计的岩石介电常数反演方法研究与应用［D］. 沈阳：东北大学， 2020.
	Zhang Li-zhen. Research and application of rock dielectric constant inversion method based on microwave radiometer［D］. Shenyang： Northeastern University， 2020.
[22]	Zhou Z L， Cai X， Cao W Z， et al. Influence of water content on mechanical properties of rock in both saturation and drying processes［J］. Rock Mechanics and Rock Engineering， 2016， 49（8）： 3009-3025.
[23]	Liu S J， Xu Z Y， Wei J L， et al. Experimental study on microwave radiation from deforming and fracturing rock under loading outdoor［J］. IEEE Transactions on Geoscience and Remote Sensing， 2016， 54（9）： 5578-5587.
[24]	罗莎，高炜，沈佳斌，等. 碱处理对聚偏二氟乙烯结构与介电性能的影响［J］. 高分子材料科学与工程， 2020， 36（5）： 42-48.
	Luo Sha， Gao Wei， Shen Jia-bin， et al. Influence of alkali treatment on the structure and dielectric properties of polyvinylidene fluoride［J］. Polymer Materials Science and Engineering， 2020， 36（5）： 42-48.
[25]	王洋，牟建新，祝存生，等. 新型低介电常数聚芳醚酮的合成及性能研究［J］. 高等学校化学学报， 2005， 26（3）： 586-588.
	Wang Yang， Mu Jian-xin， Zhu Cun-sheng， et al. Synthesis and properties of a novel kind of PEAK （poly aryl ether ketone） with lower dielectric constant［J］. Chemical Research in Chinese Universities， 2005， 26（3）： 586-588.
[26]	Yang C B， Liu N， Kuai K F. Research on relationship between spectral characteristics， physical parameters and metal elements of rocks in Xingcheng area［J］. Spectroscopy and Spectral Analysis， 2019， 39（9）： 2953-2965.
[27]	Feng Q， Liu X Y， Chen G H， et al. Dielectric， ferroelectric and energy storage properties of （1-x） Bi_0.47Na_0.47Ba_0.06TiO_3– _x BaZrO₃ glass ceramics［J］. Journal of Materials Science： Materials in Electronics， 2016， 27（6）： 6282-6291.
[28]	Xu C， Chai H J， Cao T Y， et al. Detection of dielectric constant of Pinus sylvestris var mongolica and its influencing factors［J］. BioResources， 2019， 14（2）： 4532-4542.
[29]	肖金凯. 矿物的成分和结构对其介电常数的影响［J］. 矿物学报， 1985， 5（4）： 331-337.
	Xiao Jin-kai. The effects of mineral composition and structure on dielectric constants［J］. Acta Mineralogica Sinica， 1985， 5（4）： 331-337.
[30]	杨泽前，柴肇云，张海洋，等. 电场对高岭石表面水分扩散特性的影响［J］. 煤炭学报， 2021， 46（sup1）： 222-230.
	Yang Ze-qian， Chai Zhao-yun， Zhang Hai-yang， et al. Influence of electric field on the diffusion of water on the surface of kaolinite［J］. Journal of China Coal Society， 2021， 46（sup1）： 222-230.