作者： Zhang, Liang;Zhang, Sheng;Deng, Zongwei;Ling, Tonghua

期刊： Measurement Science And Technology,2024年35(4):045406 ISSN：0957-0233

通讯作者： Zhang, L

作者机构： [Zhang, Liang; Zhang, Sheng; Deng, Zongwei; Zhang, L] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;[Zhang, Liang; Zhang, Sheng; Zhang, L] Hunan Univ Technol, Hunan Engn Res Ctr Struct Safety & Disaster Preven, Yiyang 413000, Peoples R China.;[Ling, Tonghua] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Peoples R China.

通讯机构： [Zhang, L ] H;Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;Hunan Univ Technol, Hunan Engn Res Ctr Struct Safety & Disaster Preven, Yiyang 413000, Peoples R China.

关键词： Geological surveys;Geology;Ground penetrating radar systems;Lime;Risk assessment;Signal analysis;Signal detection;Spectrum analysis;Tunnels;Wavelet analysis;Boulde and hard rock environment;Detection signal;Energy spectrum;Ground Penetrating Radar;Hard rocks;Lower frequency components;Signal time;Time-frequency characteristics;Wavelet packet energies;Wavelet scale energy spectrum;Rocks

摘要： The hard rocks in the stratum can pose safety risks and hinder the progress of urban underground tunnel construction using shield and jacking methods, thereby reducing construction efficiency and increasing construction costs. This paper utilizes wavelet scale energy spectrum, wavelet packet theory and statistical methods to conduct research on the detection of special geological formations such as hard rocks and voids, as well as the analysis of their signal time-frequency characteristics based on the ground-penetrating radar (GPR) technique. On the basis of calibrating the permittivity of different types of rock blocks, we established a forward model for detecting hard rocks and voids, and the simulated signals were analyzed in the time and frequency domains. Subsequently, laboratory experiments were conducted to perform GPR tests on different types of hard rocks in natural and water-saturated states and voids, to explore the time-frequency characteristics, frequency band energy variations, and statistical patterns of typical single-trace signals. The results show that the granite detection signal contains more low-frequency components, the sandstone detection signal contains more medium-low frequency components, while the limestone detection signal contains more medium-high frequency components in their natural state; the signal from the karst cave has relatively more low-frequency components than the signal from the empty cavity. The geometric shape of the rock has no influence on the dominant frequency and time-frequency distribution of its reflection signal. Generally, rocks with higher rebound values (hardness) also exhibit larger variance and standard deviation in frequency band energy. The research has important theoretical significance and practical value for the measurement and assessment of special geological features such as hard rocks and voids in urban underground trenchless construction. © 2024 IOP Publishing Ltd

语种： 英文

作者： 张胜;李国栋;张亮;何叶

期刊： 高教学刊,2024年10(19):70-73+78 ISSN：2096-000X

作者机构： 湖南城市学院 土木工程学院,湖南 益阳 413000;[李国栋; 张胜; 张亮; 何叶] 湖南城市学院土木工程学院

关键词： 研究生培养;土木工程专业;CiteSpace软件;研究进展与热点;可视化分析

摘要： 土木工程专业研究生培养对推动行业的技术创新和可持续发展具有至关重要的影响.该文采用CiteSpace软件,对2003-2023 年中国知网发布的 192 篇土木工程专业研究生培养相关文献进行可视化分析.通过深入探讨该领域的发展历程,研究发现,目前的核心热点包括科研创新、工程实践、国际视野和跨学科培养等方面.此外,还强调作者间交流协作的重要性,并提出持续优化培养方法,特别是在扩大研究团队规模和促进跨地域合作方面的迫切需求,从而为土木工程专业研究生培养策略的优化提供指导.

语种： 中文

作者： Zhang, Liang;Zhang, Sheng;Deng, Zongwei;Ling, Tonghua

期刊： Environmental Earth Sciences,2024年83(9):1-15 ISSN：1866-6280

通讯作者： Zhang, L

作者机构： [Zhang, Liang; Zhang, Sheng; Deng, Zongwei; Zhang, L] Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;[Zhang, Liang; Zhang, Sheng; Zhang, L] Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preven, Yiyang 413000, Peoples R China.;[Ling, Tonghua] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Peoples R China.

通讯机构： [Zhang, L ] H;Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preven, Yiyang 413000, Peoples R China.

关键词： Subgrade cavity;Ground-penetrating radar;2D undecimated wavelet transform;F-K method;Migration imaging

摘要： Timely and accurate detection and identification of cavities under urban roads is the key to road safety. Due to the inability to obtain accurate migration velocity and the difficulty of achieving complete convergence of diffraction signals of the cavity disease, traditional migration methods struggle to accurately identify and locate the subgrade cavity. This paper proposes a GPR image migration processing (TUFK method) based on 2D undecimated wavelet transform and the F-K method in accordance with the high-precision imaging of the subgrade cavity. The finite-difference forward models of subgrade cavity without and with noise are established, and the model test of cavity detection by GPR is carried out in the laboratory. Through the fine extraction and migration processing of the weak diffraction signals from the cavity, the optimal velocity required for migration is analyzed, and the TUFK method is applied to the migration process of GPR data acquired for the purpose of cavity detection. Furthermore, the proposed method is applied to the processing of GPR data acquired in the field with a cavity below the roadbed. The results show that the TUFK method can accurately extract the diffraction signals from the cavity and achieve the fine convergence of cavity diffraction signals whether in noiseless or noisy environments. Compared with the traditional Kirchhoff and F-K migration methods, this method can effectively obtain accurate migration velocity and the migration results can reflect the actual position and shape of the cavity. This study can provide a new idea and effective method for the imaging of subgrade cavity.

语种： 英文

作者： 李柏;张胜

期刊： 科教导刊：电子版,2024年(18):43-45 ISSN：1674-6813

作者机构： [李柏] 湖南城市学院 美术与设计学院/国际教育学院,湖南 益阳 413000;湖南城市学院 土木工程学院,湖南 益阳 413000;[张胜] 湖南城市学院

关键词： 就业指导;创新创业;问题;措施

摘要： 在全面建成社会主义现代化强国的新征程上,地方高校的就业指导和创新创业教育在人才培养和科技创新中起着至关重要的作用,不仅关系到学生的未来发展,还直接影响国家进步和民族未来.文章深入分析当前高校就业指导与创新创业教育课程中存在的思想引领不足、课程体系局限、师资力量薄弱与评价体系不完善等问题,从思想政治教育、课程体系构建、师资队伍建设和课程评价体系完善等方面着手,提出切实可行的优化措施,旨在全面提升就业指导与创新创业教育的质量.

语种： 中文

作者： Ling, Tonghua;Jiang, Hao;Zhang, Liang;Zhang, Sheng;Bei, Zhenghao;...

期刊： JOURNAL OF GEOPHYSICS AND ENGINEERING,2024年21(4):1071-1084 ISSN：1742-2132

通讯作者： Jiang, H

作者机构： [Bei, Zhenghao; Ling, Tonghua; Long, Bin; Jiang, Hao] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Peoples R China.;[Zhang, Liang; Zhang, Sheng] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;[Jiang, Hao] Changsha Univ Sci & Technol, 960,2nd Sect,Wanjiali RD S, Changsha 410004, Hunan, Peoples R China.

通讯机构： [Jiang, H ] C;Changsha Univ Sci & Technol, 960,2nd Sect,Wanjiali RD S, Changsha 410004, Hunan, Peoples R China.

关键词： lining void;ground penetrating radar;reverse time migration;digital morphology;edge detection

摘要： Diseases such as voids behind the initial support of the tunnel will lead to problems such as lining rupture and concrete damage in the tunnel structure, which seriously affects the driving safety in the tunnel. In tunnel construction, ground penetrating radar is frequently employed as a method for detecting hidden defects. However, when the cavity size is small, there will be a large error when the original radar data is directly interpreted, which cannot meet the needs of practical engineering. To enhance the precision in tunnel detection, the Finite-Difference Time-Domain method is used to simulate various small cavities of different shapes located behind the primary support lining of the tunnel, and the study involves examining the electromagnetic response characteristics of different kinds of holes. The migration techniques of KIRCHHOFF, F-K, and reverse time are employed to reconstruct the hole target. Furthermore, digital morphology is employed to enhance the clarity of the image. Finally, the edge detection technology is used to further extract the hole features. After that, small cavities of different shapes are buried in the established outdoor concrete model box and radar detection is carried out. The detection position of the reconstructed radar image and the actual position of the cavity in the model box are verified. The results show that compared with KIRCHHOFF migration and F-K migration, the image processed by reverse time migration is clearer and more intuitive, and can restore the contour of small holes well. The research findings can serve as a reference for the interpretation of radar data of the cavity behind the initial support of the tunnel.

语种： 英文

作者： Zhang, Shusen;Zheng, Xia;Yin, Canbin;Ye, Yunpeng;Li, Xingong

期刊： Case Studies in Construction Materials,2023年18:e01739 ISSN：2214-5095

通讯作者： Li, Xingong(lxgwood2021@163.com)

作者机构： [Li, Xingong; Zhang, Shusen; Ye, Yunpeng; Zheng, Xia] Cent South Univ Forestry Technol, Coll Mat Sci & Engn, Changsha 410004, Peoples R China.;[Yin, Canbin] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.

通讯机构： [Xingong Li] C;College of Materials Science and Engineering, Central South University of Forestry,Technology, Changsha 410004, China

关键词： Rice straw;Silicate cement;Compatibility;Hydration;Inorganic composites

摘要： In order to study the feasibility of preparing cement particle board by compounding silicate and rice straw shavings, this paper explored their compatibility by detecting the heat of hydration of both by HPLC and characterized by FTIR, SEM and XRD. The results suggested that rice straw contained a certain amount of sugars soluble in water as well as organic carboxylic acids, having toxic effects on the hydration of silicate cement and could retard the hydration reaction of silicate cement. The addition of rice straw would inhibit the generation of crystals of hydration products in the early stage of silicate cement hydration, which makes it difficult for the C-S-H gel to build a dense spatial mesh, resulting in the poor compatibility of rice straw with silicate cement. The verification experiments exhibited that the static flexural strength of straw cement particleboard was far lower than the standard value of CB/T 24312–2009 cement particleboard, indicating that rice straw was unsuitable for direct apply for the preparation of rice straw silicate cement particleboard, and the compatibility regulation of rice straw and silicate cement was required. © 2022 The Authors

语种： 英文

作者： 张亮;罗世杰;张胜;邓宗伟;洪亮

期刊： 移动信息,2023年(4):95-97 ISSN：1009-6434

作者机构： 湖南城市学院土木工程学院

关键词： 信息化教育;地下工程测试技术;教学设计与实践;虚拟仿真实验

摘要： “地下工程测试技术”是一门实践性较强的专业课程,提升学生对该课程内容的实践操作能力至关重要。文中分析了目前在“地下工程测试技术”课程教学中存在的一些问题,包括教学方式单一、教学内容陈旧等,并从创新工程教育方式与手段、校企...展开更多 “地下工程测试技术”是一门实践性较强的专业课程,提升学生对该课程内容的实践操作能力至关重要。文中分析了目前在“地下工程测试技术”课程教学中存在的一些问题,包括教学方式单一、教学内容陈旧等,并从创新工程教育方式与手段、校企合作、课程结构优化3个方面,论述了信息化教育背景下“地下工程测试技术”课程的教学模式设计与实践方式,可为该课程教学质量的提高及城市地下工程人才的培养提供有益参考。收起

语种： 中文

作者： Zhang, Liang;Zhang, Sheng;Ling, Tonghua;Huang, Fu

期刊： Journal of Applied Geophysics,2023年216:105158 ISSN：0926-9851

通讯作者： Zhang, L

作者机构： [Zhang, Liang; Zhang, Sheng; Zhang, L] Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preven, Yiyang 413000, Peoples R China.;[Zhang, Liang; Zhang, Sheng] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.;[Ling, Tonghua; Huang, Fu] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Peoples R China.

通讯机构： [Zhang, L ] H;Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preven, Yiyang 413000, Peoples R China.

关键词： Geological surveys;Geophysical prospecting;Ground penetrating radar systems;Image enhancement;Radar imaging;Signal interference;Biorthogonal wavelet;Biorthogonal wavelet decomposition;Energy-entropy;Ground penetrating radar;Interference signal;Spectra's;Spectrum whitening;Strong interference;Strong interference signal;Wavelets decomposition;Wavelet decomposition;detection method;ground penetrating radar;image processing;spectrum;steel structure;tunnel lining;wavelet analysis

摘要： In the light of the shielding effect of the strong reflection signal generated by the steel bars and the inhomogeneous of concrete materials on the weak signal in the tunnel lining detection, a high-resolution GPR image processing method of biorthogonal wavelet energy entropy in different time windows is proposed. Wavelet analysis has the characteristics of multiresolution, and wavelet entropy can represent the energy distribution characteristics of signals in different time windows with different scales. Firstly, the discrete biorthogonal wavelet transform is applied to decompose the original GPR image into subimages with different frequencies and different spatial local changes. Secondly, appropriate time windows are selected for wavelet entropy adaptive threshold processing of each subimage in the light of the different amplitude ratio of effective signal to strong interference in each subimage, and finally the reconstructed image after removing the strong reflection is spectrally whitened. Both the forward simulations and actual measurement results show that the method can effectively remove strong reflection interference, clear weak signals, and maintain the continuity of the reflection events, and compared to the conventional pulse deconvolution, predictive deconvolution and wavelet entropy methods with the same time window, this method has a more thorough interference removal effect, and the effective signal performance is more obvious, which proves the effectiveness and accuracy of the proposed method in improving the resolution of GPR image and highlighting weak signal. © 2023

语种： 英文

作者： 凌同华;陈梓浓;张胜;阳标;张亮

期刊： 铁道科学与工程学报,2023年20(9):3604-3615 ISSN：1672-7029

作者机构： [凌同华; 陈梓浓] 长沙理工大学土木工程学院;[张胜; 张亮; 阳标] 湖南城市学院土木工程学院

关键词： 隧道工程;岩性识别模型;轻量化网络;岩石岩性;目标检测

摘要： 在隧道工程地质勘察中,需要对岩石岩性进行判断和识别,以便开展工程岩体定量分析及工程地质安全评价.鉴于目前岩石岩性识别过程中存在主观性强、周期性长等问题,结合岩石表面岩性特征信息,提出基于MobileNetV3轻量化网络模型的岩石岩性快速识别方法.首先采集工程中常见的20类不同岩性的岩石图像样本并搭建图像数据集,通过构建MobileNetV3网络模型和迁移学习方法对岩石图像进行训练,获得MobileNetV3岩石岩性识别模型;然后,将MobileNetV3岩性识别模型与EfficientNet-B0,Xception和Inception-ResNet-v2网络模型的岩性识别结果进行对比,从而评估其训练效果.此外,采用MobileNet网络替换SSD模型的主干特征提取网络,构建轻量化MobileNet-SSD目标检测模型对岩石图像进行检测与识别.结果表明,MobileNetV3网络模型识别岩石岩性的准确率为98.2％,模型大小仅为12 MB,对测试集上单张图像从输入到输出识别结果的平均时间为812 ms;与其他模型相比,该模型在识别精度、模型大小和识别时间上,都具有一定优势;通过MobileNet-SSD目标检测模型,可以实现对岩石目标的定位以及多种岩石同时识别.将MobileNetV3网络模型应用于隧道掌子面岩石岩性识别中,对不同岩性以及同一岩性不同完整程度的隧道掌子面岩石,模型有较好的识别效果.本研究成果有助于提高卷积神经网络模型的可移植性以及隧道工程离线环境下岩石岩性的快速准确识别.

语种： 中文

作者： 张亮;邓泽邦;张胜;邓宗伟;李海;...

期刊： 湖南城市学院学报(自然科学版),2023年32(05):1-6 ISSN：1672-7304

作者机构： [张亮; 邓泽邦; 张胜; 邓宗伟; 李海; 陈健琼] 湖南城市学院土木工程学院

关键词： 城市地下管线;探地雷达;傅里叶变换;小波能量矩;模型试验

摘要： 城市地下管线普查对于城市综合管理、智慧城市建设起着重要作用﹒本文基于探地雷达检测技术，结合频谱分析和小波能量矩方法，通过构建的管线探测正演模型和设计的管线探测物理模型试验，对不同埋深、不同填充介质的管线探测信号功率谱及能量矩分布规律进行了探究﹒研究结果表明：含水管线探测信号主频始终小于充填空气管线的，且管线信号主频随管线埋深增加无明显变化；含水管线探测信号能量矩均值及标准差均大于充填空气管线的，且管线信号能量矩总和及标准差均随管线埋深增加而不断降低﹒

语种： 中文

作者： Ling, Tonghua;He, Wenchao;Zhang, Sheng;Zhang, Liang;Huang, Fu*;...

期刊： Journal of Applied Geophysics,2022年196:104513 ISSN：0926-9851

通讯作者： Huang, Fu

作者机构： [Ling, Tonghua; He, Wenchao; Huang, Fu; Hua, Fei] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Peoples R China.;[Zhang, Liang; Zhang, Sheng] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.

通讯机构： [Huang, Fu] C;Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Peoples R China.

关键词： Geological surveys;Geophysical prospecting;Ground penetrating radar systems;Inverse problems;Nondestructive examination;Permittivity;Quality control;Reinforcement;Signal processing;Biorthogonal wavelet base construction;Biorthogonal wavelet basis;Dielectric permittivities;Energy density analysis;Ground Penetrating Radar;Inhomogeneous medium;Time-energy density;Time-energy density analyse of wavelet transform method;Transform methods;Wavelets transform;Wavelet transforms;accuracy assessment;data inversion;dielectric property;ground penetrating radar;inhomogeneity;numerical method;permittivity;quantitative analysis;theoretical study;waveform analysis;wavelet analysis

摘要： In the field of nondestructive inspection, ground-penetrating radar (GPR) is a widely used investigation tool, usually to evaluate quality and safety in structural engineering. However, its development has been limited due to differences in the dielectric constant in inhomogeneous media. In this study, a time-energy density analysis of wavelet transform (TEDAWT) method for GPR signal singularity recognition was proposed. In addition, a biorthogonal wavelet basis with high similarity to GPR signal waveform was innovatively constructed and added into the wavelet toolbox. A model experiment was conducted to validate the feasibility of inverse calculation of the permittivity of wet clay by the TEDAWT method. Results showed that this method offered the advantages of signal denoising, resolution improvement, singularity recognition in GPR signal processing. Subsequently, a basic flow chart was established, which could be used to inversely calculate the permittivity of inhomogeneous media, and be applied to the quantitative identification of the thickness of the reinforcement protective layer in an expressway tunnel. The calculation results showed that the inverse calculation value of reinforcement protection layer thickness was 3.74% lower than the average relative theoretical error value. That improved detection accuracy provided a new method to quantitatively identify inhomogeneous media by GPR. © 2021

语种： 英文

作者： 傅浩特;张胜;周英贤;张亮;胡泽超

期刊： 江西建材,2022年(03):63-65 ISSN：1006-2890

作者机构： 湖南城市学院土木工程学院;中大检测(湖南)股份有限公司

关键词： 岩石力学;超声波测试;频谱分析;物理力学参数;曲线拟合

摘要： 为研究超声波在不同岩性岩石中的传播规律，文中利用非金属超声波仪对岩石试样进行测试，采用傅里叶变换对超声波信号进行频谱分析，得到了岩石密度和岩石回弹值、岩石纵波速度、超声波信号主振频率、动弹性模量之间的关系。研究结果表明：岩石的回弹值、纵波速度、主振频率、动弹性模量均与岩石密度存在显著的相关性。岩石的回弹值、纵波速度以及动弹性模量随岩石密度的增加而不断增加，岩石超声波信号的主振频率随岩石密度的增加反而逐渐减小。对于实际工程应用，根据给出的拟合关系式可以准确预测岩石的回弹值、纵波速度、主振频率和动弹性模量。

语种： 中文

作者： Ling, Tonghua;He, Wenchao;Zhang, Sheng;Liu, Xianjun;Huang, Fu;...

期刊： Construction and Building Materials,2022年353:129042 ISSN：0950-0618

通讯作者： He, Wenchao(hewenchao1224@stu.csust.edu.cn)

作者机构： [Liu, Wenjun; Ling, Tonghua; Liu, Xianjun; He, Wenchao; Huang, Fu] Changsha Univ Sci & Technol, Coll Civil Engn, Changsha 410114, Peoples R China.;[Zhang, Sheng] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.

通讯机构： [Wenchao He] C;College of Civil Engineering, Changsha University of Science and Technology, Changsha 410114, China

关键词： Porous mixed media;Relative dielectric constant;Ground-penetrating radar;Time-energy density analysis of the wavelet;transform method;Quantitative identification

摘要： Natural materials mostly consist of porous mixed media, the relative dielectric constant (RDC) of which is a variable. The RDC of measured materials is often simply estimated as a constant value for the purposes of ground-penetrating radar (GPR) detection, which is one of the reasons for the significant quantitative identification error of GPR results. Only by accurately measuring the RDC of porous mixed media to calibrate the electromagnetic wave velocity can accurate quantitative GPR identification results be obtained. However, the difficulty is how precisely to identify the feature points of GPR signal of the measured material. In this study, a model test was carried out in a laboratory setting on porous mixed media consisting of dry sand, dry loam, and limestone. A new method was then proposed to accurately measure the RDC of porous mixed media. On this basis, three stages of accurate measurements of GPR were proposed, namely, signal processing, wavelet analysis, and quantitative identification. Experimental results showed that the relative error rate between the measured value (5.555) and the theoretical value (7.250) of porous mixed media was 23.38%, and the relative error rate of the measured value obtained by the new method was reduced from 13.78% to 1.50% in respect of quantitative recognition of GPR. The proposed method offers both unique advantages in improving the detection accuracy of GPR and great market potential, especially for projects requiring the accuracy of non-destructive testing (NDT). In addition, this study also proposed potential methodological feasibility and research ideas for predicting the physical properties of measured materials by establishing sensitive regions within three-dimensional spaces in the future. © 2022 Elsevier Ltd

语种： 英文

作者： Zhang, Sheng;Zhang, Liang;He, Wenchao;Ling, Tonghua;Deng, Zongwei;...

期刊： Minerals,2022年12(2):234 ISSN：2075-163X

通讯作者： Zhang, L;Ling, TH

作者机构： [Zhang, Liang; Zhang, Sheng; Deng, Zongwei; Fu, Guihai; Zhang, L] Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;[Zhang, Liang; Zhang, Sheng; Deng, Zongwei; Fu, Guihai; Zhang, L] Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preve, Yiyang 413000, Peoples R China.;[Ling, Tonghua; He, Wenchao] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Peoples R China.

通讯机构： [Ling, TH ] C;[Zhang, L ] H;Hunan City Univ, Sch Civil Engn, Yiyang 413000, Peoples R China.;Hunan City Univ, Hunan Engn Res Ctr Struct Safety & Disaster Preve, Yiyang 413000, Peoples R China.;Changsha Univ Sci & Technol, Sch Civil Engn, Changsha 410114, Peoples R China.

关键词： tunnel construction;filler materials;ground-penetrating radar;wavelet bases;wavelet transform

摘要： Advanced geological prediction of tunnels has become an indispensable task to ensure the safety and effectiveness of tunnel construction before excavation in karst areas. Geological dis-asters caused by unfavorable geological conditions, such as karst caves, faults, and broken zones ahead of a tunnel face, are highly sudden and destructive. Determining how to predict the spatial location and geometric size of unfavorable geological bodies accurately is a challenging problem. In order to facilitate a three‐dimensional quantitative analysis of the filler material ahead of the tunnel face, a biorthogonal wavelet with short support, linear phase, and highly matching waveform of ground penetrating radar (GPR) wavelet is constructed by lifting a simple and general initial filter on the basis of lifting wavelet theory. A method for a time–energy density analysis of wavelet trans-forms (TEDAWT) is proposed in accordance with the biorthogonal wavelet. Fifteen longitudinal and horizontal survey lines are used to detect void fillers of different heights. Then, static correction, DC bias, gain, band‐pass filtering, and offset processing are performed in the original GPR profile to enhance reflected signals and converge diffraction signals. A slice map of GPR profile is generated in accordance with the relative position of longitudinal and horizontal survey lines in space. The wavelet transform analysis of a single‐channel signal of each survey line is performed by adopting the TEDAWT method because of the similar rule of the single‐channel signal of GPR on the waveform overlay and the ability of the constructed wavelet basis to highlight the time‐frequency characteristics of GPR signals. The characteristic value points of the first and second interfaces of the void fillers can be clearly determined, and the three‐dimensional spatial position and geometric sizes of different void fillers can be obtained. Therefore, the three‐dimensional visualization of GPR data is realized. Results show that the TEDAWT method has a good practical application effect in the quantitative identification of void fillers, which provides a basis for the interpretation of advanced geological prediction data of tunnels and for the construction decision. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

语种： 英文

作者： Zhang, Liang;Zhang, Sheng;Ling, Tonghua;Deng, Zongwei

期刊： FRONTIERS IN EARTH SCIENCE,2022年10:966222 ISSN：2296-6463

通讯作者： Zhang, L.

作者机构： [Zhang, Liang; Zhang, Sheng; Deng, Zongwei] Hunan City Univ, Coll Civil Engn, Yiyang, Peoples R China.;[Ling, Tonghua] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha, Peoples R China.

通讯机构： [Zhang, L.] C;College of Civil Engineering, China

关键词： Blasting vibration;continuous wavelet transform;Wavelet packet;Spectrum distribution;energy refinement characteristics

摘要： The analysis of time-frequency variation and energy refinement characteristics of blasting vibration signals has contributed to understanding the propagation law of blasting vibration wave and reducing the possible losses. Combined with the measured data of tunnel blasting excavation and based on the newly constructed wavelet function, the spectrum distribution and energy refinement characteristics of tunnel blasting vibration signals are deeply explored and studied. The results demonstrated that compared to the Fourier spectrum, the innovative method of scale energy spectrum can not only acquire the dominant frequency of the blasting vibration signals, but also the obtained spectrum curve is smoother and can clearly reflect the change trend of the signal spectrum. The newly constructed biorthogonal wavelet has the characteristics of high vanishing moment, high regularity and matching with the waveform variation of the measured blasting vibration signals, and can describe the subtle variation characteristics of blasting vibration signal frequency. The continuous wavelet transform energy spectrum can reflect the three-dimensional energy distribution of blasting vibration signal in the time-scale domain, and the occurrence time of frequency, the frequency duration interval and time range of blasting vibration signal can also be acquired. Wavelet packet algorithm can precisely calculate the energy distribution of each frequency component in the signal, the tunnel blasting vibration signals (YBJ1, YBJ2) generated near the power tower presents low frequency, while the signals (YBF3,YBF4) far away from the power tower presents relatively high frequency. Measures should be taken to control the vibration and resonance of power tower caused by tunnel blasting. This research is of great significance for recognizing the propagation law of vibration waves, reducing the impact of blasting on surrounding buildings, and ensuring the safety of tunnel construction and surrounding buildings.

语种： 英文

作者： Ling, Tonghua;He, Wenchao;Liu, Xianjun;Zhang, Sheng;Huang, Fu;...

期刊： Geophysical Prospecting,2022年70(6):1052-1065 ISSN：0016-8025

通讯作者： He, Wenchao(hewenchao1224@stu.csust.edu.cn)

作者机构： [Ling, Tonghua; Liu, Xianjun; He, Wenchao; Huang, Fu; Hua, Fei] Changsha Univ Sci & Technol, Coll Civil Engn, Changsha 410114, Peoples R China.;[Zhang, Sheng] Hunan City Univ, Coll Civil Engn, Yiyang 413000, Peoples R China.

通讯机构： [Wenchao He] C;College of Civil Engineering, Changsha University of Science and Technology, Changsha, 410114 China

关键词： Ground-penetrating radar;Finite difference methods;Numerical modelling;Signal processing;Wavelet

摘要： The Fisher–Yates random shuffling algorithm combined with the finite-difference time-domain method is proposed to construct a fine grid model for the forward simulation of ground-penetrating radar in mixed media. First, the finite-difference time-domain method was used to divide the coarse grid model into several fine grid models by conforming to the boundary conditions of different media, and the corresponding dielectric parameters were assigned to Yee cells in each fine grid model. Then, the Fisher–Yates random shuffling algorithm was used to randomly scramble all Yee cells with equal probability, and the array of scrambled Yee cells was recombined into a coarse grid model. Finally, the geoelectric model of mixed media was generated with the finite-difference time-domain method, and a ground-penetrating radar image excited by electromagnetic wave pulses was obtained. To explore the characteristic signals and dielectric properties of the ground-penetrating radar electromagnetic response in mixed media, image entropy theory was used to describe the ground-penetrating radar image, and waveform analysis and wavelet transform mode maximum methods were used to analyse the single-channel ground-penetrating radar signal of the mixed media. The results showed that the Fisher–Yates random shuffling–finite-difference time-domain method can be used to construct a valid and stable fine grid model for simulating ground-penetrating radar in mixed media. The model effectively inhibits electromagnetic attenuation and energy dissipation, and the wavelet transform mode maximum method explains the relative dielectric permittivity distribution of the mixed media. The findings of this study can be used as a theoretical basis for correcting radar parameters and interpreting images when ground-penetrating radar is applied to mixed media. © 2022 European Association of Geoscientists & Engineers.

语种： 英文

作者： 张亮;张胜;邓宗伟;洪亮;付贵海

期刊： 科技风,2022年(29):113-115 ISSN：1671-7341

作者机构： 湖南城市学院土木工程学院

关键词： 隧道及地下工程;教学改革;教学理念;创新路径

摘要： 伴随着城市建设的快速发展及地下空间开挖的大量兴起，“隧道及地下工程”课程的重要性越来越得到凸显。本文在阐述了“隧道及地下工程”课程的特点及其重要性的背景下，分析了该课程在传统理论教学模式、实践性教学及学生考评等方面存在的不足与困境，提出从教学理念、虚拟仿真教学等方面对该课程教学实践路径进行探索和创新，旨在为轨道交通方向人才培养提供有益思路。

语种： 中文

作者： Zhang, Sheng*;He, Wenchao;Cao, Feng;Hong, Liang

作者机构： [Hong, Liang; Zhang, Sheng] Hunan City Univ, Sch Civil Engn, Yiyang, Peoples R China.;[Hong, Liang; Zhang, Sheng] Univ Houston, Dept Mech Engn, Houston, TX 77004 USA.;[He, Wenchao] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha, Peoples R China.;[Cao, Feng] Hunan Prov Commun Planning Survey & Design Inst C, Changsha, Peoples R China.

会议名称： 17th Biennial International Conference on Engineering, Science, Construction, and Operations in Challenging Environments (Earth and Space)

会议时间： APR 19-23, 2021

会议地点： ELECTR NETWORK

会议主办单位： [Zhang, Sheng;Hong, Liang] Hunan City Univ, Sch Civil Engn, Yiyang, Peoples R China.^[Zhang, Sheng;Hong, Liang] Univ Houston, Dept Mech Engn, Houston, TX 77004 USA.^[He, Wenchao] Changsha Univ Sci & Technol, Sch Civil Engn, Changsha, Peoples R China.^[Cao, Feng] Hunan Prov Commun Planning Survey & Design Inst C, Changsha, Peoples R China.

会议论文集名称： Earth and Space 2021<&wdkj&>Earth and Space 2021<&wdkj&>Earth and Space 2021

关键词： tunnel engineering;cavern fillings;ground penetrating radar;short-time Fourier transform;forward simulation

摘要： The most important factor in restricting safe and efficient is the unfavorable geological conditions ahead of the tunnel face during tunnel construction in karst area. To avoid the occurrence of geological disasters, advanced geological forecast technology is widely used to detect the development of unfavorable geological bodies. In order to better explain the time-frequency characteristics of GPR signals of tunnel cavern fillings, the Gaussian window function is selected according to the uncertainty principle, and the short-time Fourier transform is used to analyze and process the GPR signals of cavern fillings with different properties based on forward simulation. The results show that the time-frequency spectrum based on short-time Fourier transform can meticulously describe the process of change that takes places in time and frequency plane of GPR signals, which is beneficial to accurately extract the time-frequency characteristic parameters in GPR signals. When the electromagnetic wave wavelength of the GPR transmitting antenna is shorter than the detection depth of cavern fillings, two target reflectors which reflect the upper and lower reflecting interfaces of the fillings will appear in the spectrum of forward simulation signal. The relative errors of recognition results obtained according to the reflection time interval are all less than 5%, which provides a reference for the quantitative interpretation of GPR signals of tunnel cavern fillings.

语种： 英文

作者： 张胜;张亮;付贵海;郭尤林

期刊： 中国多媒体与网络教学学报(上旬刊),2021年(09):56-58 ISSN：1673-2499

作者机构： 湖南城市学院土木工程学院

关键词： 工程教育;课程建设;现代信息技术;考核方式;人才培养

摘要： 土力学课程是土木工程专业最重要的基础课程之一,工程教育专业认证给土力学课程教学提出了更高要求。为提高土力学课程的教学效果,通过分析目前高校土力学课程教学存在的问题,本文将着力于从课前预习准备、课中翻转教学、课后复习巩固三方面进行教学探索与改革;依托现代信息技术,以学生为中心,制定课前预习准备、课中翻转教学与课后复习巩固一起综合加权纳入学生的成绩评定体系,解决学生在学习过程中遇到的枯燥和难懂的问题,帮助学生掌握扎实的理论知识,进一步提升本科教学培养的质量,满足新时代社会发展对专业技术人才创新能力与综合素质的培养需求。

语种： 中文

作者： 凌同华;欧阳雄志;刘建伟;张胜

期刊： 交通科学与工程,2021年37(02):20-27 ISSN：1674-599X

作者机构： [刘建伟; 凌同华; 欧阳雄志] 长沙理工大学土木工程学院;[张胜] 湖南城市学院土木工程学院

关键词： 隧道工程;动力响应;数值分析;爆破;隧道衬砌

摘要： 以浙江省金华市里岩垄坑2号隧道为工程背景,研究Ⅲ级围岩隧道爆破时衬砌动力响应。本文采用MinimateProTM振动监测仪对开挖洞与邻洞进行了爆破振动测量,并利用Midas GTS NX对双洞隧道进行数值模拟分析。研究结果表明:本洞初衬振动速度和位移的最大值发生在拱顶处,横向上的大小远小于纵向和竖向。对于纵向,拱顶及拱肩处的质点振动峰值速度远大于其他关键位置的,各关键位置的竖向位移和速度变化趋势相同,但仍是拱顶处最大;本洞初衬应力最大值位于拱腰处,先行洞应力最大值在左拱腰处;其速度与位移的最大值位于左拱肩;先行洞二衬与后行洞掌子面的纵向间距应为15～20m。本文研究结果可为双洞隧道的爆破施工提供指导。

语种： 中文