以贵州独山变电站内地层为研究对象,将主动源面波多道分析法(multichannel analysis of surface waves,MASW)和被动源面波空间自相关法(spatial auto correlation,SPAC)频散能量叠加,得到一条复合频散曲线。该曲线频带更宽,既能保证表...以贵州独山变电站内地层为研究对象,将主动源面波多道分析法(multichannel analysis of surface waves,MASW)和被动源面波空间自相关法(spatial auto correlation,SPAC)频散能量叠加,得到一条复合频散曲线。该曲线频带更宽,既能保证表层的分辨能力,避免形成较大的勘探盲区,又可以有效提高反演深度,获得更加精细化的横波速度模型。结合钻探资料对比标定,可赋予该模型地质意义。研究结果表明,采用MASW和SPAC相结合的分析方法,有利于从表层到深层对地层进行精细成像,了解地层的岩性结构特征。与钻探相比,该方法成本低、效率高,可为复杂城区不良地质体的探测提供重要参考依据。展开更多
Steel-concrete composite structures(SCCS)have been widely used as primary load-bearing components in large-scale civil infrastructures.As the basis of the co-working ability of steel plate and concrete,the bonding sta...Steel-concrete composite structures(SCCS)have been widely used as primary load-bearing components in large-scale civil infrastructures.As the basis of the co-working ability of steel plate and concrete,the bonding status plays an essential role in guaranteeing the structural performance of SCCS.Accordingly,efficient non-destructive testing(NDT)on interfacial debondings in SCCS has become a prominent research area.Multi-channel analysis of surface waves(MASW)has been validated as an effective NDT technique for interfacial debonding detection for SCCS.However,the feasibility of MASW must be validated using experimental measurements.This study establishes a high-frequency data synchronous acquisition system with 32 channels to perform comparative verification experiments in depth.First,the current sensing approaches for high-frequency vibration and stress waves are summarized.Secondly,three types of contact sensors,namely,piezoelectric lead-zirconate-titanate(PZT)patches,accelerometers,and ultrasonic transducers,are selected for MASW measurement.Then,the selection and optimization of the force hammer head are performed.Comparative experiments are carried out for the optimal selection of ultrasonic transducers,PZT patches,and accelerometers for MASW measurement.In addition,the influence of different pasting methods on the output signal of the sensor array is discussed.Experimental results indicate that optimized PZT patches,acceleration sensors,and ultrasonic transducers can provide efficient data acquisition for MASW-based non-destructive experiments.The research findings in this study lay a solid foundation for analyzing the recognition accuracy of contact MASW measurement using different sensor arrays.展开更多
Multichannel analysis of surface waves is a noninvasive technique for subsurface shear wave velocity imagining. This method is one of the most effective geophysical tools for geotechnical investigations. In this paper...Multichannel analysis of surface waves is a noninvasive technique for subsurface shear wave velocity imagining. This method is one of the most effective geophysical tools for geotechnical investigations. In this paper, we present multichannel surface wave data acquisition in a non-conventional manner in alluvium deposits. Fixed receiver and multi-source offset geometry were applied to obtain field data. The data processing comprised of generating CMP cross-correlated traces and then inversion to obtain dispersion curves. The inversion of dispersion curves is achieved by employing a genetic algorithm to obtain subsurface shear wave velocity. Finally, the one-dimensional shear wave models are obtained. The multi-source offset data acquisition with fixed receiver geometry technique in combination with CMP cross-correlation gathers for data processing worked in a quite efficient way to obtain subsurface shear wave model.展开更多
The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering problems.Wuhan,with a population of 13.74×10^(6) and approximately 1161 km^(2)of soluble rocks i...The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering problems.Wuhan,with a population of 13.74×10^(6) and approximately 1161 km^(2)of soluble rocks in the urban area of 8569.15 km^(2),predominantly consists of concealed karst areas where occasional ground collapse events occur,posing significant threats to underground engineering projects.To address these challenges,a comprehensive geological survey was conducted in Wuhan,focusing on major karstrelated issues.Geophysical methods offer advantages over drilling in detecting concealed karst areas due to their efficiency,non-destructiveness,and flexibility.This paper reviewed the karst geological characteristics in Wuhan and the geophysical exploration methods for karst,selected eight effective geophysical methods for field experimentation,evaluated their suitability,and proposed method combinations for different karst scenarios.The results show that different geophysical methods have varying applicability for karst detection in Wuhan,and combining multiple methods enhances detection effectiveness.The specific recommendations for method combinations provided in this study serve as a valuable reference for karst detection in Wuhan.展开更多
This paper presents the integration of seismic refraction and multichannel analysis of surface wave(MASW)measurements to investigate the anisotropy of P-and S-wave velocities.Additionally,synthetic forward modelling i...This paper presents the integration of seismic refraction and multichannel analysis of surface wave(MASW)measurements to investigate the anisotropy of P-and S-wave velocities.Additionally,synthetic forward modelling is presented as a tool for supporting seismic anisotropy studies.The geophysical measurements of cracks allowed to recognise the fracturing of a granite rock mass in a Paleozoic granite quarry(Strzegom,Poland)and a dolomite rock mass in a Triassic dolomite quarry(Podlesna,Poland).Application of the forward modelling supports the interpretation of seismic methods,simplifying data processing and verifying the final results based on data from difficult seismic conditions.As a result of direct measurements,two crack systems were determined in granite rock mass:NNE-SSW and NNW-SSE,and two in dolomite rock mass:NNE-SSW and NW-SE.Furthermore,the numerical results show the relationship between the highest values of P-and S-wave velocities and separated crack systems which allowed an unequivocal interpretation of the direction of stress,resulting in the deformations.The obtained information is promising to be helpful in mining exploration for optimising excavation works.展开更多
文摘以贵州独山变电站内地层为研究对象,将主动源面波多道分析法(multichannel analysis of surface waves,MASW)和被动源面波空间自相关法(spatial auto correlation,SPAC)频散能量叠加,得到一条复合频散曲线。该曲线频带更宽,既能保证表层的分辨能力,避免形成较大的勘探盲区,又可以有效提高反演深度,获得更加精细化的横波速度模型。结合钻探资料对比标定,可赋予该模型地质意义。研究结果表明,采用MASW和SPAC相结合的分析方法,有利于从表层到深层对地层进行精细成像,了解地层的岩性结构特征。与钻探相比,该方法成本低、效率高,可为复杂城区不良地质体的探测提供重要参考依据。
基金National Natural Science Foundation of China under Grant (Nos.52192662,52020105005,51908320)the Beijing Nova Program under Grant No.20220484012+1 种基金the Interdisciplinary Research Project for Young Teachers of USTB (Fundamental Research Funds for the Central Universities,FRF-IDRY-22-013)the Key Laboratory for Intelligent Infrastructure and Monitoring of Fujian Province (Huaqiao University,IIM-01-05)。
文摘Steel-concrete composite structures(SCCS)have been widely used as primary load-bearing components in large-scale civil infrastructures.As the basis of the co-working ability of steel plate and concrete,the bonding status plays an essential role in guaranteeing the structural performance of SCCS.Accordingly,efficient non-destructive testing(NDT)on interfacial debondings in SCCS has become a prominent research area.Multi-channel analysis of surface waves(MASW)has been validated as an effective NDT technique for interfacial debonding detection for SCCS.However,the feasibility of MASW must be validated using experimental measurements.This study establishes a high-frequency data synchronous acquisition system with 32 channels to perform comparative verification experiments in depth.First,the current sensing approaches for high-frequency vibration and stress waves are summarized.Secondly,three types of contact sensors,namely,piezoelectric lead-zirconate-titanate(PZT)patches,accelerometers,and ultrasonic transducers,are selected for MASW measurement.Then,the selection and optimization of the force hammer head are performed.Comparative experiments are carried out for the optimal selection of ultrasonic transducers,PZT patches,and accelerometers for MASW measurement.In addition,the influence of different pasting methods on the output signal of the sensor array is discussed.Experimental results indicate that optimized PZT patches,acceleration sensors,and ultrasonic transducers can provide efficient data acquisition for MASW-based non-destructive experiments.The research findings in this study lay a solid foundation for analyzing the recognition accuracy of contact MASW measurement using different sensor arrays.
文摘Multichannel analysis of surface waves is a noninvasive technique for subsurface shear wave velocity imagining. This method is one of the most effective geophysical tools for geotechnical investigations. In this paper, we present multichannel surface wave data acquisition in a non-conventional manner in alluvium deposits. Fixed receiver and multi-source offset geometry were applied to obtain field data. The data processing comprised of generating CMP cross-correlated traces and then inversion to obtain dispersion curves. The inversion of dispersion curves is achieved by employing a genetic algorithm to obtain subsurface shear wave velocity. Finally, the one-dimensional shear wave models are obtained. The multi-source offset data acquisition with fixed receiver geometry technique in combination with CMP cross-correlation gathers for data processing worked in a quite efficient way to obtain subsurface shear wave model.
基金jointly supported by the project of Chinese National Natural Science Foundation(42107485)National Key R&D Program(2020YFC1512400,2018YFC800804)China Geological Survey(DD20190282,DD20221734,and DD20230323)。
文摘The construction of modern livable cities faces challenges in karst areas,including ground collapse and engineering problems.Wuhan,with a population of 13.74×10^(6) and approximately 1161 km^(2)of soluble rocks in the urban area of 8569.15 km^(2),predominantly consists of concealed karst areas where occasional ground collapse events occur,posing significant threats to underground engineering projects.To address these challenges,a comprehensive geological survey was conducted in Wuhan,focusing on major karstrelated issues.Geophysical methods offer advantages over drilling in detecting concealed karst areas due to their efficiency,non-destructiveness,and flexibility.This paper reviewed the karst geological characteristics in Wuhan and the geophysical exploration methods for karst,selected eight effective geophysical methods for field experimentation,evaluated their suitability,and proposed method combinations for different karst scenarios.The results show that different geophysical methods have varying applicability for karst detection in Wuhan,and combining multiple methods enhances detection effectiveness.The specific recommendations for method combinations provided in this study serve as a valuable reference for karst detection in Wuhan.
基金funded by the National Science Centre,Poland(NCN)(Grant No.2020/37/N/ST10/01486).
文摘This paper presents the integration of seismic refraction and multichannel analysis of surface wave(MASW)measurements to investigate the anisotropy of P-and S-wave velocities.Additionally,synthetic forward modelling is presented as a tool for supporting seismic anisotropy studies.The geophysical measurements of cracks allowed to recognise the fracturing of a granite rock mass in a Paleozoic granite quarry(Strzegom,Poland)and a dolomite rock mass in a Triassic dolomite quarry(Podlesna,Poland).Application of the forward modelling supports the interpretation of seismic methods,simplifying data processing and verifying the final results based on data from difficult seismic conditions.As a result of direct measurements,two crack systems were determined in granite rock mass:NNE-SSW and NNW-SSE,and two in dolomite rock mass:NNE-SSW and NW-SE.Furthermore,the numerical results show the relationship between the highest values of P-and S-wave velocities and separated crack systems which allowed an unequivocal interpretation of the direction of stress,resulting in the deformations.The obtained information is promising to be helpful in mining exploration for optimising excavation works.
