桥梁多位于水陆交界处,地势空旷,极易遭受雷击。对桥梁雷电暂态特性及相关效应进行定量分析,可为桥梁的防雷设计提供科学的数据支撑。本文以单塔斜拉索桥梁为例,利用CDEGS(Current Distribution Electromagnetic Interference Grounding...桥梁多位于水陆交界处,地势空旷,极易遭受雷击。对桥梁雷电暂态特性及相关效应进行定量分析,可为桥梁的防雷设计提供科学的数据支撑。本文以单塔斜拉索桥梁为例,利用CDEGS(Current Distribution Electromagnetic Interference Grounding and Soil Structure Analysis)软件建立桥梁三维仿真模型,模拟一般斜拉索结构桥梁的塔顶、斜拉索和桥面分别遭受直击雷时,桥梁磁场、跨步电压及雷电流分布情况。结果表明:(1)雷击斜拉索时,桥梁电子信息设备安装处磁场强度峰值最大,雷击塔顶时次之,雷击桥面时最小;雷击斜拉索时桥梁下方地面处的跨步电压峰值最大,雷击桥面时桥梁下方地面处的跨步电压峰值最小;(2)斜拉索上雷电流的大小分布与雷击点位置、斜拉索与接地体之间的距离以及斜拉索长度有关,斜拉索离接地体位置越近,长度越短,其上流过的雷电流越大;(3)接地体上雷电流的大小分布与雷击点位置及接地体的布设位置相关。距离雷击点位置越近,接地体上的雷电流幅值越大,布设在中间位置的接地体由于屏蔽效应雷电流呈现大幅减小的现象;布设在边缘位置的接地体上的雷电流波前时间变化不大,对原始雷电波陡度的削减作用不明显,而布设在中间位置的接地体上雷电流波前时间呈大幅升高的趋势,降低了雷电波因陡度大而造成的危害。展开更多
The Daxinganling area collided during the Late Paleozoic.The study area Hongwei-Xiongguan-Songheyi Dongshan area is located at the superimposed transition site of the Paleozoic paleo-Asian tectonic-metallogenic domain...The Daxinganling area collided during the Late Paleozoic.The study area Hongwei-Xiongguan-Songheyi Dongshan area is located at the superimposed transition site of the Paleozoic paleo-Asian tectonic-metallogenic domain and the Mesozoic-Cenozoic Pacific Ocean tectonic-mineralization area.It is a good ore-forming fluid channel and has very good ore metallogenic geological conditions.The comprehensive research and metallogenic prediction of the geological background and geochemical characteristics of this area are carried out.It is believed that this area has good prospecting potential,and the prospecting area is circled.Suggestions for further prospecting work in this area are put forward.展开更多
文摘桥梁多位于水陆交界处,地势空旷,极易遭受雷击。对桥梁雷电暂态特性及相关效应进行定量分析,可为桥梁的防雷设计提供科学的数据支撑。本文以单塔斜拉索桥梁为例,利用CDEGS(Current Distribution Electromagnetic Interference Grounding and Soil Structure Analysis)软件建立桥梁三维仿真模型,模拟一般斜拉索结构桥梁的塔顶、斜拉索和桥面分别遭受直击雷时,桥梁磁场、跨步电压及雷电流分布情况。结果表明:(1)雷击斜拉索时,桥梁电子信息设备安装处磁场强度峰值最大,雷击塔顶时次之,雷击桥面时最小;雷击斜拉索时桥梁下方地面处的跨步电压峰值最大,雷击桥面时桥梁下方地面处的跨步电压峰值最小;(2)斜拉索上雷电流的大小分布与雷击点位置、斜拉索与接地体之间的距离以及斜拉索长度有关,斜拉索离接地体位置越近,长度越短,其上流过的雷电流越大;(3)接地体上雷电流的大小分布与雷击点位置及接地体的布设位置相关。距离雷击点位置越近,接地体上的雷电流幅值越大,布设在中间位置的接地体由于屏蔽效应雷电流呈现大幅减小的现象;布设在边缘位置的接地体上的雷电流波前时间变化不大,对原始雷电波陡度的削减作用不明显,而布设在中间位置的接地体上雷电流波前时间呈大幅升高的趋势,降低了雷电波因陡度大而造成的危害。
文摘The Daxinganling area collided during the Late Paleozoic.The study area Hongwei-Xiongguan-Songheyi Dongshan area is located at the superimposed transition site of the Paleozoic paleo-Asian tectonic-metallogenic domain and the Mesozoic-Cenozoic Pacific Ocean tectonic-mineralization area.It is a good ore-forming fluid channel and has very good ore metallogenic geological conditions.The comprehensive research and metallogenic prediction of the geological background and geochemical characteristics of this area are carried out.It is believed that this area has good prospecting potential,and the prospecting area is circled.Suggestions for further prospecting work in this area are put forward.