用于地面核爆源区电磁脉冲环境评估的工程等效电导率测量和反演方法

Engineering Equivalent Conductivity Measurement and Inversion Method for Field Environmental Assessment of SREMP

地面核爆源区电磁脉冲(SREMP)可穿透工程岩土介质,对地下工程内的电子信息设备造成严重影响。为评估地下工程内的SREMP场环境,提出基于连续波等效的SREMP近区场测试方案,搭建等效试验测试系统,对系统中线天线近区场特性进行研究。通过线天线近地磁感应强度的试验测试,验证该测试系统的可行性。在此基础上利用时域有限差分算法对测点处的大地等效电导率进行反演研究,并对一定深度地下工程典型频点处的场环境进行计算。结果表明,该方法可针对不同的大地介质开展地下工程SREMP场环境评估,为研究SREMP效应和工程防护设计提供了参考。

The source region electromagnetic pulse(SREMP)can penetrate the engineering geotechnical medium,which has a serious impact on the electronic information equipment in the underground engineering.A test scheme of near-field region of SREMP is proposed based on the equivalent test of continuous wave in order to evaluate the environment of underground engineering.An equivalent test system is built,and the near-field characteristics of antenna are studied.The magnetic induction intensity of line antenna near the earth is test,and the feasibility of the test system is verified.On this foundation,the inversion study of equivalent conductivity of the earth is made by the finite-difference time-domain(FDTD)algorithm,and the field environment at typical frequency points in underground engineering at a certain depth is calculated.The proposed method can be used to evaluate the environment of SREMP in underground engineering for different earth media,which provides a reference for studying the SREMP effect and engineering protection design.