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岩石力学与工程学报 2001年第4期20卷 481-491页

作者： wang yujie , yin jianhua , chen zuyu ( Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hong Kong, China) ( China Institute of Water Resources and Hydropower Research, Beijing 100044 China) 香港工业大学香港中国水利水电科学研究院北京 100044

A numerical method for bearing capacity analysis by the upper bound theorem is presented. Based on the well- known Mohr-Coulomb failure criterion and the associated flow rule, the present method establishes kinematically admissible velocity field within assumed failure mechanism and a work-energy balance equation for determination of the ultimate bearing capacity of a strip footing by minimization. Since the bearing capacity is due to the interaction between (or joined influence of) friction of angle φ, cohesion c, surcharge load q and unit weight of soil γ, a general equation of bearing capacity considering the interaction is derived. Three bearing capacity factors considering the cohesion, surcharge and weight of soil are obtained using two approaches: (a) considering the joined influence and (b) separate calculation. The critical failure mechanisms for the two approaches are obtained and compared. The computed values of the three factors using the two approaches are compared to those published in the literatures. Agreement and differences are discussed.

关键词： bearing capacity strip footing upper bound plasticity numerical analysis limit analysis

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TBM破岩关键参数跨工程转换关系

地球科学 2024年第5期49卷 1722-1735页

作者：李海波李旭王双敬陈祖煜荆留杰北京交通大学城市地下工程教育部重点实验室北京100044 中国水利水电科学研究院岩土工程研究所北京100048 中铁工程装备集团有限公司河南郑州450016

TBM信息化施工中采集了海量数据,通过数据挖掘建立机器学习模型,是实现TBM智能化的前提.然而在TBM新建工程初期,由于数据量稀少导致机器学习模型预测效果不佳;同时由于TBM设备结构和刀盘直径存在差异,基于历史工程训练得到的机器学习模... 详细信息

TBM信息化施工中采集了海量数据,通过数据挖掘建立机器学习模型,是实现TBM智能化的前提.然而在TBM新建工程初期,由于数据量稀少导致机器学习模型预测效果不佳;同时由于TBM设备结构和刀盘直径存在差异,基于历史工程训练得到的机器学习模型也并不适用于新建工程.为了解决这一瓶颈问题,基于单刀受力分析、经验方法和扭剪实验模型等多种换算关系推导得到了仅与刀具数量和刀盘直径有关的物理不变量,利用由不变量组成的转换方案,可以对新建工程数据进行转换;之后针对围岩分类和机器学习模型上的应用效果,比选出最佳的破岩关键参数转换方案;进而采用遗传算法,以比选得到的转换方案不变量作为初值,迭代搜索出适合当前工程的最优转换方案不变量.研究结果表明,引绰工程(新建工程)数据经过不变量的转换后输入到引松工程(历史工程)机器学习模型,其刀盘扭矩T和刀盘推力F预测结果的拟合优度R2分别达到了0.84和0.70.本研究采用该转换方案不变量,可将不同工程的TBM施工数据归一化,将其统一到同一个框架下进行分析,实现了基于历史工程数据训练得到的机器学习模型指导新建工程施工.研究结果可为TBM机器学习模型跨工程应用提供参考.

关键词： TBM 机器学习破岩关键参数不变量遗传算法岩土工程工程地质

知识驱动和数据驱动在TBM智能施工机器学习中的应用

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土木工程学报 2024年第6期57卷 1-12页

作者：陈祖煜范立涛张云旆肖浩汉王琳西安理工大学省部共建西北旱区生态水利国家重点实验室陕西西安710048 中国水利水电科学研究院流域水循环模拟与调控国家重点实验室北京100048

依托引绰济辽工程(YC)和引松供水工程(YS),从理论分析、统计检验等方面系统回顾并总结基于知识驱动方法提取的现场贯入指标FPI和扭矩贯入指标TPI在TBM智能施工机器学习中的应用。从智能预测围岩分类和掘进参数两方面出发,将基于特征参... 详细信息

依托引绰济辽工程(YC)和引松供水工程(YS),从理论分析、统计检验等方面系统回顾并总结基于知识驱动方法提取的现场贯入指标FPI和扭矩贯入指标TPI在TBM智能施工机器学习中的应用。从智能预测围岩分类和掘进参数两方面出发,将基于特征参数的预测结果与通过数据驱动获得的结果进行比较。研究结果表明:通过知识驱动获取的参数FPI和TPI可以降低数据维度和噪音,提高预测效率。在围岩分类智能预测方面,知识驱动和数据驱动方法均表现出较好的精度水平;在掘进参数预测方面,知识驱动的预测精度远高于数据驱动。作者认为单独使用FPI和TPI或者将其与数据驱动参数结合,可以丰富TBM领域机器学习的输入参数,获得较好的预测成果。

关键词： TPI FPI 知识驱动数据驱动围岩分类掘进参数预测

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多维度视角下中国人口城镇化发展模式

中国人口·资源与环境 2024年第1期34卷 139-149页

作者：黄祖宇王桂新湖南大学公共管理学院湖南长沙410000 复旦大学人口研究所上海200433

在中国进入人口城镇化发展中后期的背景下,透过人口城镇化水平快速提升的表象,从结构层面对人口城镇化发展模式进行多维度探究,有助于清楚识别与理解城镇化发展的内在机制与规律,发现城镇化发展进程中存在的问题并提出合理的应对策略。... 详细信息

在中国进入人口城镇化发展中后期的背景下,透过人口城镇化水平快速提升的表象,从结构层面对人口城镇化发展模式进行多维度探究,有助于清楚识别与理解城镇化发展的内在机制与规律,发现城镇化发展进程中存在的问题并提出合理的应对策略。该研究利用第六次和第七次人口普查分县数据,以地级行政区为基本统计单元,并将数据汇总至省级和区域层面,从城乡人口变动、城镇人口增长来源、城镇人口空间分布三个维度对2010—2020年中国人口城镇化发展模式进行了深入探究。实证结果显示:①中国人口城镇化率的提升是城镇人口和乡村人口变动共同作用的结果,城镇人口增长的贡献度高于乡村人口减少的贡献度。②乡城人口迁移仍是中国城镇人口增长的绝对主力,其次为区划调整增长,最末为自然增长。③城镇人口空间分布趋于分散,县域城镇人口变动对城镇化率的贡献度略高于市辖区城镇人口变动。④东北地区城镇化率的提升主要依赖于乡村人口的减少,城镇人口已出现自然负增长和净迁出的现象,且该地区大多数县域城镇人口流失严重。据此,各级政府应及时审视过往人口城镇化发展的结构特征,在不断促进经济发展和完善公共服务供给的前提下,重点结合区域或城市自身的自然条件特点和城镇人口增减、分布状况,制定更有针对性的人口城镇化发展策略,探索出一条符合自身实际的可持续性人口城镇化发展道路。

关键词：人口城镇化发展城乡人口变动人口增长来源人口空间分布

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Quantitative deterministic versus probability analyses based on a safety margin criterion

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Science China(Technological Sciences) 2014年第10期57卷 1988-2000页

作者： chen zuyu chen LiHong XU Jiacheng SUN Ping WU Chao wang yujie State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin Department of Geotechnical Engineering China Institute of Water Resources and Hydropower Research School of Civil Engineering Beijing Jiaotong University China International Engineering Consulting Corporation

This paper proposes a new criterion called the ratio of safety margin(RSM)for use in the areas of the global factor of safety,reliability and limit states analyses with reference to their respective allowable *** equation for calculating RSM based on the reliability index is *** for proving the applicability of this criterion include a theoretical demonstration in a simple one-variable case;an investigation on a test problem involving two random variables,followed by a slope stability study on a 156 m high embankment dam and an illustrative example presented in a EuroCode 7 *** of the ratios of safety margin in the three areas provides a quantitative way to accommodate the analytical results within the same theoretical framework and makes the outcomes mutually comparable and supportive,which is much more enlightening than that would be the case by considering only one of *** RSMs for reliability and limit states methods has also helped solve the key issue concerning the uniqueness of the partial factors calibrated from a particular‘target case’.

关键词： factor of safety reliability index partial factor ratio of safety margin embankment dam reliability analysis

2011~2020年中国城市人口增长来源构成分析

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中国人口科学 2024年第1期38卷 98-112页

作者：黄祖宇王桂新湖南大学公共管理学院复旦大学人口研究所

文章利用中国2010年以来全国人口普查、全国1%人口抽样调查及其他相关统计数据,测算并考察2011~2020年城市人口增长来源构成及其对城市化发展的贡献。研究结果表明,考察期内中国城市人口规模仍在持续增大,但增长速度有所放缓;2011~2020... 详细信息

文章利用中国2010年以来全国人口普查、全国1%人口抽样调查及其他相关统计数据,测算并考察2011~2020年城市人口增长来源构成及其对城市化发展的贡献。研究结果表明,考察期内中国城市人口规模仍在持续增大,但增长速度有所放缓;2011~2020年的新增城市人口中,56%来自人口迁移,26%来自行政区划变动,自然增长仅占18%,人口迁移仍是推动中国城市化发展的主导因素;城市人口增长来源构成未发生根本性变化,但三大增长来源对城市化发展贡献的差异趋于减小,迁移增长对城市化发展的主导作用有所弱化,自然增长与区划变动的影响相对增大。探讨城市人口增长来源构成及其对城市化发展的贡献,对把握中国新时期城市化发展动力机制的变化,推进城市化高质量发展具有重要意义。

关键词：人口城市化自然增长迁移增长区划变动增长城市人口增长构成

Study of risk acceptance criteria for dams

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Science China(Technological Sciences) 2015年第7期58卷 1263-1271页

作者： LI ShouYi ZHOU XingBo wang yujie ZHOU JianPing DU XiaoHu chen zuyu Institute of Water Resources and Hydropower Engineering Xi'an University of Technology Department of Geotechnical Engineering China Institute of Water Resources and Hydropower Research Power Construction Corporation of China Ltd. China Renewable Energy Engineering Institute

This paper discusses the methods of establishing risk criteria for dams and reviews the application of dam risk criteria for individuals and societies in different countries or districts. Given the conditions in China and considering the public safety and acceptance of dam risk, historical dam break data and current design standards, individual and societal risk criteria for dams are proposed. The tolerable dam risk criteria for individuals should be set to 10-5-10-7 per annum based on project scale, for ex- ample, approximately 1.0xl0 7 per annum, which corresponds to a reliability index of 4.2 based on a 100-year lifespan for a first-class or large project. The societal limit for risk tolerance for dams should be set to approximately 10-3-10-5 per annum, corresponding to the fatality range from 1 to 100 and be horizontally extended to 1000, and F-N curves are proposed. It was also found that the reliability indices of Chinese Standard （GB 50199-2013） and Eurocodel （2002） are different, but they have the same level of safety measured by the annual probability of failure. The research results have significance for establishing dam risk criteria.

关键词： dam risk criteria acceptable risk annual probability of failure dam safety

Inward particle transport driven by biased endplate in a cylindrical magnetized plasma

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Plasma Science and Technology 2024年第3期26卷 126-130页

作者：盖跃徐田超肖池阶郭志彬王晓钢何任川杨肖易张祖煜袁瑞鑫 State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China Department of Physics Harbin Institute of TechnologyHarbin 150001People's Republic of China

The inward particle transport is associated with the formation of peaked density profiles,which contributes to improve the fusion rate and the realization of steady-state *** active control of inward particle transport is considered as one of the most critical issues of magnetic confinement ***,it is realized preliminarily by adding a biased endplate in the Peking University Plasma Test(PPT)*** results reveal that the inward particle flux increases with the bias voltage of the *** is also found that the profile of radial electric field(Er)shear is flattened by the increased bias *** velocity fluctuations affect the inward particle more than density fluctuations,and the frequency of the dominant mode driving inward particle flux increases with the biased voltage applied to the *** experimental results in the PPT device provide a method to actively control the inward particle flux using a biased endplate and enrich the understanding of the relationship between E_(r)×B shear and turbulence transport.

关键词： inward particle transport biased endplate turbulent transport

An approach to quick and easy evaluation of the dam breach flood

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Science China(Technological Sciences) 2019年第10期62卷 1773-1782页

作者： chen zuyu PING ZiYi wang NaiXin YU Shu chen ShuJing Institute of Geotechnical Engineering Zhejiang UniversityHangzhou310027China Key Laboratory of Soft Soils and Geoenvironmental Engineering of Ministry of Education Zhejiang UniversityHangzhou310058China State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin China Institute of Water Resources and Hydropower ResearchBeijing100038China Department of Engineering Training National Academy for Mayors of ChinaBeijing100029China

In the context of an impending dam failure, quick evaluation of dam breach flood is necessary. Previous studies provided an approach to calculate the dam breach hydrograph using an Excel spreadsheet based on the improved soil erosion model and numerical algorithm. However, calculation of the breach lateral enlargement requires the modeling of the successive collapse of the breach banks. It is time-consuming with special training, which is difficult to provide during an emergency. This study proposes that the lateral enlargement process can be modeled using a hyperbolic relationship with sufficient accuracy. Consequently, field engineers can perform the dam breach analysis along with the sensitive study for a target case within 1 h in an Excel spreadsheet which is self-tutorial. This paper presents this easy and quick approach based on only fifteen input parameters that can be determined based on the experience. This approach can also be used for the preliminary study when a dam safety planning work is undertaken.

关键词： dam breach flood breach lateral enlargement hyperbolic relationship

3-dimensional slope stability analyses using non-associative stress-strain relationships

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Science China(Technological Sciences) 2009年第9期52卷 2517-2527页

作者： chen zuyu SUN Ping wang yujie ZHANG HongTao Department of Geotechnical Engineering China Institute of Water Resources and Hydropower ResearchBeijing 100048China Department of Civil Engineering Beijing University of Science and TechnologyBeijing 430074China

The research work presented in this paper refers to a new slope stability analysis method used for landslide risk evaluations. It is an extension of the 3-dimensional upper-bound slope stability analysis method proposed by chen et al. in 2001,which employs the Mohr-Coulomb's associative flow rule. It has been found that in a 3-dimensional area,a prism may not be able to move at friction angles to all its surrounding interfaces,as required by this associative rule,and convergence problems may occasionally arise. The new method establishes two velocity fields:(i) The plastic one that represents a non-associative and the best representative dilation behavior,and (ii) the virtual one that permits the solution for factor of safety in the work and energy balance equation. The new method can then allow any input value of dilation angle and thus solve the convergence problem. A practical application to a concrete dam foundation is illustrated.

关键词： non-associative flow rule slope stability limit analysis 3-dimension