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Applied Mathematics and Mechanics(English Edition) 2023年第3期44卷 411-430页

作者： Sha XIAO Zhongqi Yue Key Laboratory of Urban Security and Disaster Engineering of China Ministry of Education Beijing University of TechnologyBeijing 100124China Department of Civil Engineering The University of Hong KongHong KongChina

The paper develops and examines the complete solutions for the elastic field induced by the point load vector in a general functionally graded material(FGM)model with transverse isotropy.The FGMs are approximated with n-layered materials.Each of the n-layered materials is homogeneous and transversely isotropic.The complete solutions of the displacement and stress fields are explicitly expressed in the forms of fifteen classical Hankel transform integrals with ten kernel functions.The ten kernel functions are explicitly expressed in the forms of backward transfer matrices and have clear mathematical properties.The singular terms of the complete solutions are analytically isolated and expressed in exact closed forms in terms of elementary harmonic functions.Numerical results show that the computation of the complete solutions can be achieved with high accuracy and efficiency.

关键词： functionally graded material(FGM) transverse isotropy elasticity closedform singular solution Green's function point load vector

In situ strength profiles along two adjacent vertical drillholes from digitalization of hydraulic rotary drilling

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第1期15卷 146-168页

作者： Xuefan Wang Peng Peng Zhigang Shan Zhongqi Yue Department of Civil Engineering The University of Hong KongHong KongChina PowerChina Huadong Engineering Corporation Limited HangzhouChina

Drilling speed and associated analyses from factual field data of hydraulic rotary drilling have not been fully utilized.The paper provides the reference and comparison for the utilization of drilling information from two adjacent vertical drillholes that were formed with the same hydraulic rotary drilling machine and bit.The analysis of original factual data is presented to obtain the constant drilling speed during net drilling process.According to the factual data along two adjacent drillholes,the digitalization results respectively include 461 linear zones and 210 linear zones with their constant drilling speeds and associated drilling parameters.The digitalization results can accurately present the spatial distributions and interface boundaries of drilled geomaterials and the results are consistent with the paralleled site loggings.The weighted average drilling speeds from 2.335 m/min to 0.044 m/min represent 13 types of drilled geomaterials from soils to hard rocks.The quantitative relation between drilling speed and strength property is provided.The digitalization results can statistically profile the basic strength quality grades of III to VI from soils to hard rocks.The thickness distributions of four strength quality grades are presented for each individual type of geomaterials along two drillholes.In total,50.2%of geomaterials from drillhole A are grade IV and 57.4%of geomaterials from drillhole B are grade III.The digitalization results can offer an accurate and cost-effective tool to quantitatively describe the spatial distribution and in situ strength profile of drilled geomaterials in the current drilling projects.

关键词： Drilling process monitoring(DPM) Hydraulic rotary coring process Constant drilling speed Coring-resistant strength

Model-free adaptive robust control method for high-speed trains

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Transportation Safety and Environment 2024年第1期6卷 93-102页

作者： zhongqi Li Liang Zhou Hui Yang yue Yan School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang 330013JiangxiChina State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure East China Jiaotong UniversityNanchang 330013JiangxiChina

Aiming at the robustness issue in high-speed trains(HSTs)operation control,this article proposes a model-free adaptive control(MFAC)scheme to suppress disturbance.Firstly,the dynamic linearization data model of train system under the action of measurement disturbance is given,and the Kalman filter(KF)based on this model is derived under the minimum variance estimation criterion.Then,according to the KF,an anti-interference MFAC scheme is designed.This scheme only needs the input and output data of the controlled system to realize the MFAC of the train under strong disturbance.Finally,the simulation experiment of CRH380A HSTs is carried out and compared with the traditional MFAC and the MFAC with attenuation factor.The proposed control algorithm can effectively suppress the measurement disturbance,and obtain smaller tracking error and larger signal to noise ratio with better applicability.

关键词： automatic train operation(ATO) model-free adaptive control(MFAC) disturbance suppression minimum variance estimation Kalman filtering(KF) partial format data model

基于数字图像的真实细观非均质岩土力学分析数值方法

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地球物理学报 2022年第1期65卷 108-118页

作者：岳中琦香港大学土木工程系中国香港

本文介绍基于真实非均质岩土材料的数值方法与研究进展.这些方法运用新发展的数字图像技术,获取真实岩土和混凝土材料的细观非均质分布,再进行定量细观结构研究,采用数值计算程序,定量分析它们的物理力学响应,为解决限制岩土和混凝土力... 详细信息

本文介绍基于真实非均质岩土材料的数值方法与研究进展.这些方法运用新发展的数字图像技术,获取真实岩土和混凝土材料的细观非均质分布,再进行定量细观结构研究,采用数值计算程序,定量分析它们的物理力学响应,为解决限制岩土和混凝土力学进一步发展的非均质材料假设问题提供了有效途径.本文介绍该方法的研究背景和三项主要内容.包括真实细观非均质岩土材料力学数值分析方法,非均质岩土材料数值网格计算方法,和非均质岩土材料力学响应重要规律.

关键词：数字图像处理岩土力学地质力学数值方法非均质岩土材料混凝土

Digital monitoring of rotary-percussive drilling with down-the-hole hammer for profiling weathered granitic ground

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1615-1636页

作者： Wendal Victor yue Siyuan Wu Manchao He Yafei Qiao zhongqi Quentin yue Department of Geotechnical Engineering College of Civil EngineeringTongji UniversityShanghai200092China Department of Civil Engineering Faculty of EngineeringThe University of Hong KongPokfulam RoadHong KongChina State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and TechnologyBeijing100083China Key Laboratory of Geotechnical and Underground Engineering of Ministry of Education Tongji UniversityShanghai200092China

Rock and geotechnical engineering investigations involve drilling holes in ground with or without retrieving soil and rock samples to construct the subsurface ground profile.On the basis of an actual soil nailing drilling for a slope stability project in Hong Kong,this paper further develops the drilling process monitoring(DPM)method for digitally profiling the subsurface geomaterials of weathered granitic rocks using a compressed airflow driven percussive-rotary drilling machine with down-the-hole(DTH)hammer.Seven transducers are installed on the drilling machine and record the chuck displacement,DTH rotational speed,and five pressures from five compressed airflows in real-time series.The mechanism and operations of the drilling machine are elaborated in detail,which is essential for understanding and evaluating the drilling data.A MATLAB program is developed to automatically filter the recorded drilling data in time series and classify them into different drilling processes in sub-time series.These processes include penetration,push-in with or without rod,pull-back with or without rod,rod-tightening and rod-untightening.The drilling data are further reconstructed to plot the curve of drill-bit depth versus the net drilling time along each of the six drillholes.Each curve is found to contain multiple linear segments with a constant penetration rate,which implies a zone of homogenous geomaterial with different weathering grades.The effect from fluctuation of the applied pressures is evaluated quantitatively.Detailed analyses are presented for accurately assess and verify the underground profiling and strength in weathered granitic rock,which provided the basis of using DPM method to confidently assess drilling measurements to interpret the subsurface profile in real time.

关键词： Drilling process monitoring(DPM) Down-the-hole(DTH)hammer Percussive-rotary drilling Weathering granitic rocks

Extended wet sieving method for determination of complete particle size distribution of general soils

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 242-257页

作者： Shengnan Ma Yi Song Jiawei Liu Xingyu Kang zhongqi Quentin yue Department of Civil Engineering The University of Hong KongHong KongChina

The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional method and presents an extended wet sieving method.The extended method uses both the steel sieves and the nylon filter cloth sieves.The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm,0.038 mm,0.014 mm,0.012 mm,0.0063 mm,0.004 mm,0.003 mm,0.002 mm,and 0.001 mm,respectively.The extended method uses five steps to separate the general soil into many material sub-groups of gravel,sand,silt and clay with known particle size ranges.The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups.The extended method is demonstrated with a general soil of completely decomposed granite(CDG)in Hong Kong,China.The silt and clay materials with different particle size ranges are further examined,checked and verified using stereomicroscopic observation,physical and chemical property tests.The results further confirm the correctness of the extended wet sieving method.

关键词： Particle size distribution(PSD) General soil Silt Clay Wet sieving Physical and chemical properties

Tidal flat erosion of the Huanghe River Delta due to local changes in hydrodynamic conditions

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Acta Oceanologica Sinica 2014年第7期33卷 116-124页

作者： JIA Yonggang ZHENG Jiewen yue zhongqi LIU Xiaolei SHAN Hongxian Key Laboratory of Marine Environment and Ecology Ministry of Education Ocean University of China First Institute of Oceanology State Oceanic Administration Key Laboratory of State Oceanic Administration for Marine Sedimentology and Environmental Geology First Institute of Oceanography State Oceanic Administration Department of Civil Engineering University of Hong Kong

An ideal nature system for the study of post-depositional submarine mass changing under wave loading was selected in the intertidal platform of the subaqueous Huanghe River Delta, a delta formed during period from 1964 to 1976 as the Huanghe River discharged into the Bohai Gulf by Diaokou distributary. A road embankment constructed for petroleum recovery on the inter-tidal platform in 1995 induced the essential varieties of hydrodynamic conditions on the both sides of the road. With both sides sharing similarities in （1） initial sedimentary environment, （2） energetic wave loading, （3） differential hydrodynamic conditions in later stages, （4） enough long-range action, and （5） extreme shallow water inter-tidal platforms; the study is representative and feasible as well. Two study sites were selected on each side of the road, and a series of measurements, samplings, laboratory experiments have been carried out, including morphometry, hydrodynamic conditions, sediment properties, granularity composition, and fractal dimension calculation of the topography in the two adjacent areas. It was observed that in the outer zone, where wave loading with high magnitude prevailed, the tidal flat was bumpy and exhibited a high erosion rate and high fractal dimension. Further, the fractal dimension diminished quickly, keeping with the enlarging of calculative square size. However in the inner zone, where the hydrodynamic condition was weak, the tidal fiat was fiat and exhibited a low erosion rate and low fractal dimensions; the fractal dimension diminished with the enlarging of calcu- lative square size. The fractal dimensions in the different hydrodynamic areas equalized increasingly as the calculative square size accreted to threshold, indicating that the hydrodynamic condition plays a significant role in topography construction and submarine delta erosion process. Additionally, the later differentiation of sediment properties, granularity composition, microstructure characteristics, and mineral composition induced by the diffe

关键词： hydrodynamic conditions coastal erosion sea-bed topography in-situ measurement fractal calculation

土质斜坡存在唯一最小安全系数的数据作图论证及原因分析

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工程地质学报 2022年第1期30卷 83-100页

作者：岳中琦康兴宇香港大学土木工程系中国香港999077

本文通过数据作图法揭示了土体黏聚力和内摩擦角对斜坡安全系数作用的不同规律,并论证了一般土质斜坡存在唯一最小安全系数及其原因。本文在土质斜坡中划分了大量的潜在滑移面,并定义了每一个潜在滑移面所拥有的4类安全系数FOS^(c×φ)... 详细信息

本文通过数据作图法揭示了土体黏聚力和内摩擦角对斜坡安全系数作用的不同规律,并论证了一般土质斜坡存在唯一最小安全系数及其原因。本文在土质斜坡中划分了大量的潜在滑移面,并定义了每一个潜在滑移面所拥有的4类安全系数FOS^(c×φ)、FOS^(c)、FOS^(φ)和FOS^(c+φ)。基于极限平衡的条分法计算了滑移面的4类安全系数,并使用数据作图法揭示和确定了这4类安全系数值随潜在滑移面深度d变化的4条特征和规律。由土体黏聚力和内摩擦角共同作用的安全系数FOS^(c×φ)包络线随d的增加先单调下降,到达一段最小值区间后,再单调上升。因此,它必然存在一个总体最小值。仅由土体黏聚力贡献的FOS^(c)包络线随d的增加先快速、再缓慢单调下降。仅由土体内摩擦角贡献的安全系数FOS^(φ)包络线随d的增加线性上升。FOS^(c)与FOS^(φ)之和FOS^(c+φ)数值几乎等同于FOS^(c×φ)数值。这4条规律揭示了土体黏聚力和内摩擦角对斜坡安全系数作用的不同规律,并论证了一般斜坡存在最小安全系数及其原因。本文进一步论证和揭示了这4条特征和规律适用于5种经典有限条分法的计算结果,适用于考虑地下孔隙水压强作用的计算结果,和考虑斜坡土体分层不均质影响的计算结果。特别地,地下孔隙水会加深拥有最小安全系数的潜在滑移面深度。土体黏聚力对斜坡安全系数贡献随潜在滑移面深度增大而减小,土体内摩擦角对斜坡安全系数贡献随潜在滑移面深度增大而增大。这两种强度随深度的相反贡献规律导致了一般土质斜坡存在唯一最小安全系数。

关键词：斜坡稳定性分析最小安全系数极限平衡条分法黏聚力内摩擦角数据作图法

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表述途径的介词短语及其介词的内涵表达

语言科学 2013年第4期12卷 394-402页

作者：岳中奇广东技术师范学院国际教育学院广东广州510665

途径题元角色具有[+经由对象]、[+媒介]、[+外谓]、[+先然]四个语义特征,存在有"空间路径"、"依凭物"和"事件"三个变体,可由介词"通过"和"经过(经)"标记构成途径介词短语及其蕴涵句。介词"通过"的语义功能在于对"途径"的凸显,而"经过"... 详细信息

途径题元角色具有[+经由对象]、[+媒介]、[+外谓]、[+先然]四个语义特征,存在有"空间路径"、"依凭物"和"事件"三个变体,可由介词"通过"和"经过(经)"标记构成途径介词短语及其蕴涵句。介词"通过"的语义功能在于对"途径"的凸显,而"经过"的语义功能则在于对"途径历程"的凸显。正是这种不同的功能制约着两者间的替换。

关键词：途径题元介词短语内涵特征变体类别语义功能

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岩爆的压缩流体包裹体膨胀力源假说

力学与实践 2015年第3期37卷 287-294页

作者：岳中琦香港大学土木工程系

岩爆是地下工程中的一种奇异力学破坏现象.开挖后的围岩块石突然、猛烈地向开挖空间弹射、抛掷和喷出.它具局部性、突发性、隐蔽性、滞后性、无前兆性、高初速度和高冲击动能.岩爆常常导致深部岩石工程重大人员伤亡和经济损失.虽然人们... 详细信息

岩爆是地下工程中的一种奇异力学破坏现象.开挖后的围岩块石突然、猛烈地向开挖空间弹射、抛掷和喷出.它具局部性、突发性、隐蔽性、滞后性、无前兆性、高初速度和高冲击动能.岩爆常常导致深部岩石工程重大人员伤亡和经济损失.虽然人们对岩爆做了大量研究,岩爆的成因机理依然是公认的"国际岩石力学领域的世界性难题".本文指出、分析、论证了造成这个"世界性难题"的原因是,国际岩石力学领域忽略了连续完整岩石中微小流体包裹体的存在和异常作用.本文进一步提出、分析和论证了封闭在完整岩石中的微细流体包裹体可能处于被压缩状态,能够拥有高压强,能够造成完整岩石内部的局部异常高地应力场.岩石开挖可导致封闭在岩石内部的众多微细高压缩流体包裹体重新随时间而渗流、移动和相变,再造成局部完整脆性围岩的岩爆.对岩石流体包裹体的力学研究能让我们破解世界性岩爆难题.

关键词：岩爆岩石力学深部岩石工程流体包裹体封闭应力高地应力