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Comparisons between centrifuge and numerical modeling results for slope toppling failure

Science China(Technological Sciences) 2015年第9期58卷 1497-1508页

作者： CHEN zuyu GONG WenJun MA GuoWei WANG Jie HE Lei XING YiChuan XING JianYing School of Transportation Science and Engineering Beihang University Department of Geotechnical Engineering China Institute of Water Resources and Hydropower School of Civil and Resource Engineering University of Western Australia Institute of Mechanics Chinese Academy of Sciences Department of Civil Engineering Monash University Yellow River Engineering Consulting Co. Ltd.

This paper presents series studies on the toppling mechanism by centrifuge tests and numerical simulations. Two different discrete element methods, i.e., the continuum-based discrete element method(CDEM) and the discontinuous deformation analysis(DDA), are adopted. The modeling results show that both the methods can accurately capture the failure modes of the centrifuge tests, including three distinct zones and two failure surfaces. Comparisons are made between the physical test and numerical simulation results. The critical inclination angle of the tilting table where the slope models are fixed on can be moderately predicted by the two methods, with different degrees of precision. The error between the test results and the simulated results is within 1% for the slope models without rock-bridges by both CDEM and DDA. However, it is amplified for the staggered-joint models that simulate the rock-bridges. With DDA, the average error is about 5%, and the maximum error is up to 17%. While with CDEM, the errors for the aligned-joint models are ranged from 1% to 6%, and it is from 10% to 29% for the staggered-joint models. The two numerical methods show the capability in simulating toppling failure of blocky rock mass with and without rock-bridges. The model with rock-bridges which provides a certain bending resistance is more stable than the one without any rock-bridge. In addition, the two failure surfaces were observed, which is different from the common understanding that only one failure surface appears.

关键词：数值模拟倾倒破坏边坡离心模型试验离心机非连续变形分析故障模式离散元方法

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Spatial Characteristics of Extreme Rainfall over China with Hourly through 24-Hour Accumulation Periods Based on National-Level Hourly Rain Gauge Data

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Advances in Atmospheric Sciences 2016年第11期33卷 1218-1232页

作者： Yongguang ZHENG Ming XUE Bo LI Jiong CHEN zuyu TAO National Meteorological Centre Beijing 100081 China School of Atmospheric Sciences Nanjing University Nanjing 210023 China Center for Analysis and Prediction of Storms Oklahoma University Norman OK 73072 USA University of Illinois at Urbana-Champaign Champaign IL 61820 USA Peking University Beijing 100871 China

Hourly rainfall measurements of 1919 national-level meteorological stations from 1981 through 2012 are used to document,for the first time,the climatology of extreme rainfall in hourly through 24-h accumulation periods in China. Rainfall amounts for 3-,6-,12- and 24-h periods at each station are constructed through running accumulation from hourly rainfall data that have been screened by proper quality control procedures. For each station and for each accumulation period,the historical maximum is found,and the corresponding 50-year return values are estimated using generalized extreme value theory. Based on the percentiles of the two types of extreme rainfall values among all the stations,standard thresholds separating Grade I,Grade II and Grade III extreme rainfall are established,which roughly correspond to the 70th and 90th percentiles for each of the accumulation periods. The spatial characteristics of the two types of extreme rainfall are then examined for different accumulation periods. The spatial distributions of extreme rainfall in hourly through 6-h periods are more similar than those of 12- and 24-h periods. Grade III rainfall is mostly found over South China,the western Sichuan Basin,along the southern and eastern coastlines,and in the large river basins and plains. There are similar numbers of stations with Grade III extreme hourly rainfall north and south of 30°N,but the percentage increases to about 70% south of 30°N as the accumulation period increases to 24 hours,reflecting richer moisture and more prolonged rain events in southern China. Potential applications of the extreme rainfall climatology and classification standards are suggested at the end.

关键词： extreme rainfall meteorological historical moisture eastern north coastal monsoon seasonal

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基于五体理论探讨膝骨关节炎的诊治

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中医药导报 2024年第7期30卷 171-175,179页

作者：赵浩茗张乐张子鸣刘科华盛汤祖宇熊逸啸匡建军湖南中医药大学湖南长沙410208 湖南省中医药研究院湖南长沙410006

五体理论是中医藏象学说的外延,对于防治膝骨关节炎(KOA)具有一定的成效,但目前缺少系统理论阐述其科学内涵及诊治。根据五体理论与KOA的内在联系,阐述五体理论辨治KOA的科学内涵。认为五体理论与KOA存在功能-解剖联系和经络学的生理联... 详细信息

五体理论是中医藏象学说的外延,对于防治膝骨关节炎(KOA)具有一定的成效,但目前缺少系统理论阐述其科学内涵及诊治。根据五体理论与KOA的内在联系,阐述五体理论辨治KOA的科学内涵。认为五体理论与KOA存在功能-解剖联系和经络学的生理联系,五体痹痿是KOA的核心病机。从五体诊治KOA即从皮、脉、筋、肉、骨5个维度进行综合立体论治。五体相合,五脏相安,才能使膝关节保持良好功能状态。

关键词：膝骨关节炎五体理论五体痹五体痿

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Numerical study on structure of meso-β scale rainstorm system during IOP523 of HUAMEX

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Chinese Science Bulletin 2002年第20期47卷 1729-1733,1764页

作者： Qingli Wu Min Chen Hongqing Wang zuyu Tao Department of Atmospheric Science College of Physics Peking University Beijing 100871 China

One of the scientific goals of HUAMEX (Torrential Rainfall Experiment over Both Sides of the Taiwan Strait and Adjacent Area), a special project in the National '863' Scientific Project, is to reveal meso-β scale structure of heavy rainfall. However, limited by the observational instruments, the resolution of the data attained from the outfield scientific observation network cannot reveal the meso-β scale structure. A 36-h numerical simulation of heavy rainfall case from May 23 to May 24, 1998 during IOP523 of HUAMEX was performed by the mesoscale numerical model of PSU/NCAR MM5, and the meso-p scale structure of con-vective system was examined based on the model output in this note. The results point out that the meso-β scale features of the heavy rainfall are clear considerably at low, middle and upper levels, respectively. There is a strong ageostrophic feature between the geopotential height field and the wind field on the upper level. The vertical cross sections of 54 km coarse grid and 18 km

关键词： heavy rainfall 3-D structure numerical simulation meso-β scale.

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Pain management using Han’s acupoint nerve stimulator combined with patient-controlled analgesia following neurosurgery A randomized case control study

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Neural Regeneration Research 2008年第7期3卷 809-812页

作者： Junming Ye zuyu Zhu Cheng Huang Jun Wei Department of Anesthesia First Affiliated Hospital of Gannan Medical College Ganzhou 341000 Jiangxi Province China Department of Neurology First Affiliated Hospital of Gannan Medical College Ganzhou 341000 Jiangxi Province China Department of Physiology Gannan Medical College Ganzhou 341000 Jiangxi Province China

BACKGROUND： Han＇s acupoint nerve stimulator （HANS） has been frequently used to relieve pain by promoting the central nerve system＇s release of endogenous opioid peptides through electric stimulation to the body surface. OBJECTIVE： To investigate the pain-relieving effects of HANS, combined with patient-controlled analgesia, following neurosurgery, and to observe adverse reactions and effects. DESIGN, TIME AND SETTING： A randomized control observation was performed at the Department of Neurology in the First Affiliated Hospital of Gannan Medical College （Ganzhou, Jiangxi Province, China） from January 2005 to February 2006. PARTICIPANTS： Forty patients, who were selected for craniotomy and required pain relief following surgery at the Department of Neurology in the First Affiliated Hospital of Gannan Medical College （China）, were included in this study. METHODS： Forty patients underwent neurosurgery and were randomly divided into two groups： patient-controlled analgesia plus HANS （＋HANS, n = 20） and patient-controlled analgesia （-HANS, n = 20）. Both groups were well matched in baseline data. Automatic syringe infusion pump ZZB-150 was the product of Nantong Aipeng Medical Instruments Co., Ltd. （China）. Patient-controlled analgesia consisted of 100 mL 0.02% lappaconitine/0.02% metoclopramide. LH-402 HANS instrument was produced in Beijing （China）, with a serial number of 402183. The HANS instrumentation was used to stimulate the Hegu-Laogong acupoint on one side and Jiaogan, Shenmen penetrating Shen, Waifei, Naogan penetrating Pizhixia ear acupoints on the affected side for one hour, with 2-hour intervals. The disperse-dense wave was alternating, with a 2/100 Hz frequency of electrical stimulation. MAIN OUTCOME MEASURE： The scores of visual analogue scale and incidence of adverse reaction were observed in two groups following surgery. RESULTS： Compared with the HANS group, the visual analogue scale scores were remarkably lower in the ＋HANS group six hours a

关键词： neurosurgery Han's acupoint nerve stimulator pain management lappaconitine

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Advanced prediction of tunnel boring machine performance based on big data

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Geoscience Frontiers 2021年第1期12卷 331-338页

作者： Jinhui Li Pengxi Li Dong Guo Xu Li zuyu Chen Department of Civil and Environmental Engineering Harbin Institute of Technology(Shenzhen)ShenzhenChina School of Civil Engineering Beijing Jiaotong UniversityBeijingChina China Institute of Water Resources and Hydropower Research BeijingChina

Predicting the performance of a tunneling boring machine is vitally important to avoid any possible accidents during tunneling *** prediction is not straightforward due to the uncertain geological conditions and the complex rock-machine *** on the big data obtained from the 72.1 km long tunnel in the Yin-Song Diversion Project in China,this study developed a machine learning model to predict the TBM performance in a real-time *** total thrust and the cutterhead torque during a stable period in a boring cycle was predicted in advance by using the machine-returned parameters in the rising period.A long short-term memory model was developed and its accuracy was *** results show that the variation in the total thrust and cutterhead torque with various geological conditions can be well reflected by the proposed *** real-time predication shows superior performance than the classical theoretical model in which only a single value can be obtained based on the single measurement of the rock *** improve the accuracy of the model a filtering process was *** indicate that filtering the unnecessary parameters can enhance both the accuracy and the computational ***,the data deficiency was discussed by assuming a parameter was *** is found that the missing of a key parameter can significantly reduce the accuracy of the model,while the supplement of a parameter that highly-correlated with the missing one can improve the prediction.

关键词： TBM Big data Machine learning LSTM neural network Data efficiency Data deficiency

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松辽盆地北部青山口组夹层型页岩油形成地质条件及勘探潜力

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大庆石油地质与开发 2024年第3期43卷 38-48页

作者：蒙启安张金友吴伟康德江王金伟于丹孙祖宇刘丽娟刘帅刘金凤张智聪于婷婷多资源协同陆相页岩油绿色开采全国重点实验室黑龙江大庆163712 中国石油大庆油田有限责任公司黑龙江大庆163458 中国石油大庆油田有限责任公司勘探开发研究院黑龙江大庆163712

松辽盆地北部青山口组是大庆油田重要的页岩产油层,主要发育泥纹型和夹层型2种类型的页岩油,其中泥纹型页岩油已经在Q9油层取得效益勘探,夹层型页岩油近2年也受到了广泛关注,部分探井取得较好效果,展现了一定的资源规模,是大庆油田增储... 详细信息

松辽盆地北部青山口组是大庆油田重要的页岩产油层,主要发育泥纹型和夹层型2种类型的页岩油,其中泥纹型页岩油已经在Q9油层取得效益勘探,夹层型页岩油近2年也受到了广泛关注,部分探井取得较好效果,展现了一定的资源规模,是大庆油田增储建产的重要接替领域。基于钻井、测井、岩心和实验分析资料,通过对青山口组沉积相、砂体分布、储层宏微观特征和含油性的系统分析,明确了松辽盆地白垩系青山口组夹层型页岩油形成的地质条件及勘探潜力。结果表明:青山口组沉积时期,主要发育北部和西部物源,沉积微相类型主要为水下分流河道、河口坝、远砂坝、席状砂、浊积砂和砂质碎屑流,夹层砂岩在全区大面积分布,沿着物源方向逐渐减薄;夹层型页岩油砂岩储层主要发育粒间孔和溶蚀孔,有效孔隙度一般为6%~12%,页岩储层主要发育粒间孔、晶间孔、有机生烃缝等,砂岩和页岩均具有较好的储集能力;青山口组夹层型页岩油源储一体近距离运移立体成藏,砂岩、页岩普遍含油,在成熟烃源岩内为纯油区,大规模连续成藏;按照有效烃源岩范围、砂岩分布范围、储层特征、黏土矿物含量、油水关系等地质条件,综合划分了青山口组夹层型页岩油发育的有利区带,初步估算资源量潜力为25×10^(8) t,展现出良好的勘探前景。主要参数对比结果表明,齐家南和古龙西地区夹层砂岩相对较厚、源岩品质相对较好,是近期增储建产的现实区带。

关键词：松辽盆地北部青山口组夹层型页岩油地质条件勘探潜力

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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：安全性概率分析定量确定可靠性指数基础极限状态斜坡稳定性 RSM

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Centrifuge Model Tests and Numerical Simulations of the Impact of Underwater Explosion on an Air-Backed Steel Plate

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Computer Modeling in Engineering & Sciences 2019年第1期118卷 139-155页

作者： Zhijie Huang zuyu Chen Xiaodan Ren Jing Hu Xuedong Zhang Lu Hai MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou310058China Institute of Geotechnical Engineering Zhejiang UniversityHangzhou310058China China Institute of Water Resources and Hydropower Research Beijing100048China School of Civil Engineering Tongji UniversityShanghai200092China.

Damage and threats to hydraulic and submarine structures by underwater explosions(UNDEXs)have raised much *** centrifuge model test,compared to prototype test,is a more promising way to examine the problem while reducing cost and satisfying the similitude requirements of both Mach and Froude numbers *** study used a systematic approach employing centrifuge model tests and numerical simulations to investigate the effects of UNDEXs on an air-backed steel *** methodical centrifuge tests of UNDEXs were *** shock wave pressure,bubble oscillation pressure,acceleration and the strain of the air-backed steel plate were recorded and compared with numerical studies using the finite element analysis(FEA)commercial software *** implementing empirically derived and physically measured pressures into the numerical models,the effects of the shock wave and bubble oscillation on the steel plate were ***,the numerical results were in agreement with the experimental *** results showed that the peak pressure of an UNDEX has a significant effect on the peak acceleration of the steel plate and that the impulse of the UNDEX pressure governs the peak strain of the steel plate.

关键词： Centrifuge model tests numerical simulation underwater explosion shock wave bubble oscillation.

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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 *** 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 *** tolerable dam risk criteria for individuals should be set to 10-5–10-7 per annum based on project scale,for example,approximately 1.0×10-7 per annum,which corresponds to a reliability index of 4.2 based on a 100-year lifespan for a first-class or large *** 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 *** was also found that the reliability indices of Chinese Standard(GB 50199-2013)and Eurocode1(2002)are different,but they have the same level of safety measured by the annual probability of *** research results have significance for establishing dam risk criteria.

关键词：风险接受准则大坝可靠性指标风险标准中国标准安全水平设计标准失效概率

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