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Theoretical investigation on axial cyclic performance of monopile in sands using interface constitutive models

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2645-2662页

作者： pan zhou Jingpei Li Kaoshan Dai Stefan Vogt Seyedmohsen Miraei Department of Geotechnical Engineering Tongji UniversityShanghai200092China Department of Civil Geo and Environmental EngineeringTechnical University of MunichFranz-Langinger-Str.10München81245Germany Department of Civil Engineering Sichuan UniversityChengdu610065China

Cyclic loads generated by environmental factors,such as winds,waves,and trains,will likely lead to performance degradation in pile foundations,resulting in issues like permanent displacement accumulation and bearing capacity *** paper presents a semi-analytical solution for predicting the axial cyclic behavior of piles in *** solution relies on two enhanced nonlinear load-transfer models considering stress-strain hysteresis and cyclic degradation in the pile-soil *** parameters are calibrated through cyclic shear tests of the sand-steel interface and laboratory geotechnical testing of sands.A novel aspect involves the meticulous formulation of the shaft loadtransfer function using an interface constitutive model,which inherently inherits the interface model’s advantages,such as capturing hysteresis,hardening,degradation,and particle *** semi-analytical solution is computed numerically using the matrix displacement method,and the calculated values are validated through model tests performed on non-displacement and displacement piles in *** results demonstrate that the predicted values show excellent agreement with the measured values for both the static and cyclic responses of piles in *** displacement pile response,including factors such as bearing capacity,mobilized shaft resistance,and convergence rate of permanent settlement,exhibit improvements compared to non-displacement piles attributed to the soil squeezing *** methodology presents an innovative analytical framework,allowing for integrating cyclic interface models into the theoretical investigation of pile responses.

关键词： Piles Cyclic degradation Load-transfer models Interface constitutive model Semi-analytical solution Model tests

Deep insight of unique phase transition behaviors and mechanism in Zr_(2)Co-H isotope system with ultra-low equilibrium pressure

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Rare Metals 2024年第1期43卷 212-224页

作者： Yang Liu pan-pan zhou Xue-Zhang Xiao Jia-Cheng Qi Jia-Peng Bi Tiao Ying Xing-Wen Feng Yan Shi Wen-Hua Luo Li-Xin Chen State Key Laboratory of Silicon Materials School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China Institute of Materials China Academy of Engineering PhysicsMianyang 621907China Key Laboratory of Advanced Materials and Applications for Batteries of Zhejiang Province Hangzhou 310013China

Efficient capture,safe storage and release of tritium from the international thermonuclear experimental reactor(ITER) reaction exhaust gas is a perplexing problem,and the development of an efficient tritium-getter material with ultra-low hydrogenation equilibrium pressure is considered as a reliable *** this work,Zr_(2)Co alloy was selected as a tritium-getter material and prepared through induction levitation *** performance test results show that Zr_(2)Co exhibits an ultra-low hydrogenation equilibrium pressure of 3.22 × 10^(-6) Pa at 25℃ and excellent hydriding kinetics under a low hydrogen pressure of 0.005 ***,unique phase transition behaviors were presented in Zr_(2)Co-H ***,Zr_(2)CoH_(5) formed by Zr_(2)Co hydrogenated at room temperature is initially decomposed into ZrH_(2) and ZrCoH_(3) at200 ℃.With the temperature increasing to 350 ℃,ZrCoH_(3)is dehydrogenated to ZrCo,and then ZrCo further reacts with ZrH_(2) at 650 ℃ to reform Zr_(2)Co and *** the staged phase transition pathways during dehydrogenation,the decomposition of Zr_(2)CoH_(5) occurs preferentially,which is well accordance with both the smallest reaction energy barrier and the maximum reaction spontaneity that are determined respectively from kinetics activation energy and thermodynamics Gibbs free ***,first principles calculation results indicate that the stronger binding of hydrogen in interstitial environments of ZrCoH_(3)and ZrH_(2) triggers the hydrogen-stabilized phase transformation of Zr_(2)CoH_(5).The unique phase transition mechanisms in Zr_(2)Co-H system can shed light on the further exploration and regulation of analogous staged phase transition of hydrogen storage materials.

关键词： Zr_(2)Co alloy Tritium-getter materials Ultralow equilibrium hydrogen pressure Phase transition mechanism

基于界面本构模型的砂土中单桩荷载−沉降响应预测方法

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岩土力学 2024年第6期45卷 1686-1698页

作者：周攀李镜培李盼盼刘耕云张超哲同济大学岩土及地下工程教育部重点实验室上海200092 同济大学地下建筑与工程系上海200092 东南大学岩土工程研究所江苏南京211189

基于界面本构模型提出了一种新的砂土中单桩荷载沉降响应的预测方法。首先,从土−结构界面本构模型出发推导了严格的桩−土界面非线性荷载传递模型,该模型承继了界面本构模型特征,能够模拟桩−土界面上发生的应变硬化/软化、剪胀与应力路... 详细信息

基于界面本构模型提出了一种新的砂土中单桩荷载沉降响应的预测方法。首先,从土−结构界面本构模型出发推导了严格的桩−土界面非线性荷载传递模型,该模型承继了界面本构模型特征,能够模拟桩−土界面上发生的应变硬化/软化、剪胀与应力路径依赖性等行为。此外,采用双曲线荷载传递模型模拟桩端−土相互作用的非线性应力−位移关系。上述荷载传递模型所需参数可以通过室内界面剪切试验和土工试验进行校准。继而,基于荷载传递法,提出了单桩荷载沉降响应分析的一维计算模型,并采用迭代算法进行数值求解。最后,将理论解答与已报道的模型试验、自主开展的模型桩试验以及数值模拟结果进行比较,以验证所提出的理论方法的正确性。试验结果表明,预测值与实测值吻合较好,且该方法能够很好地预测非位移桩与位移桩的荷载沉降响应。提出了一个基于界面本构模型的单桩荷载沉降响应分析框架,为竖向荷载下砂土中单桩优化设计提供了理论参考。

关键词：单桩砂土荷载-沉降响应桩-土相互作用界面本构模型模型试验

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Association of cardiometabolic multimorbidity with all-cause and cardiovascular disease mortality among Chinese hypertensive patients

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Journal of Geriatric Cardiology 2024年第2期21卷 211-218页

作者： Luo-Xi XIAO Zi-Yu WANG Jiang-Tao LI Hai-Mei WANG Yi-Ming HAO pan zhou Yu-Lin HUANG Qiu-Ju DENG Yong-Chen HAO Na YANG Li-Zhen HAN Zhao YANG Ping-Ping JIA Yue QI Jing LIU Center for Clinical and Epidemiologic Research Beijing Anzhen HospitalCapital Medical UniversityBeijing Institute of HeartLung and Blood Vessel DiseasesBeijing Municipal Key Laboratory of Clinical EpidemiologyBeijingChina

BACKGROUND Hypertension usually clusters with multiple ***,the association between cardiometabolic multimorbidity(CMM)and mortality in hypertensive patients is *** study aimed to investigate the association between CMM and all-cause and cardiovascular disease(CVD)mortality in Chinese patients with *** The data used in this study were from the China National Survey for Determinants of Detection and Treatment Status of Hypertensive Patients with Multiple Risk Factors(CONSIDER),which comprised 5006 participants aged 19–91 *** was defined as the presence of one or more of the following morbidities:diabetes mellitus,dyslipidemia,chronic kidney disease,coronary heart disease,and *** proportional hazard models were used to calculate the hazard ratios(HR)with 95%CI to determine the association between the number of CMMs and both all-cause and CVD *** Among 5006 participants[mean age:58.6±10.4 years,50%women(2509 participants)],76.4%of participants had at least one *** mortality rate was 4.57,4.76,8.48,and 16.04 deaths per 1000 person-years in hypertensive patients without any comorbidity and with one,two,and three or more morbidities,*** the fully adjusted model,hypertensive participants with two cardiometabolic diseases(HR=1.52,95%CI:1.09–2.13)and those with three or more cardiometabolic diseases(HR=2.44,95%CI:1.71–3.48)had a significantly elevated risk of all-cause *** findings were similar for CVD mortality but with a greater increase in risk *** In this study,three-fourths of hypertensive patients had *** with two or more comorbidities was associated with a significant increase in the risk of all-cause and cardiovascular mortality among hypertensive patients,suggesting more intensive treatment and control in this high-risk patient group.

关键词： hypertensive patients morbidity

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基于“肺阳虚”探析支气管哮喘的发病机制

中国民族民间医药 2024年第10期33卷 6-9页

作者：周攀成都中医药大学四川成都610000

支气管哮喘是目前最常见的慢性呼吸道疾病。中医认为哮喘的主要病理因素便是痰,痰凝聚伏藏于肺,则成为发病的潜在“夙根”。形成原因是素体肺气不足,津液不能正常宣散敷布,不能通调水道,易酿湿成痰,痰饮内伏。《素问·阴阳应象大论》中... 详细信息

支气管哮喘是目前最常见的慢性呼吸道疾病。中医认为哮喘的主要病理因素便是痰,痰凝聚伏藏于肺,则成为发病的潜在“夙根”。形成原因是素体肺气不足,津液不能正常宣散敷布,不能通调水道,易酿湿成痰,痰饮内伏。《素问·阴阳应象大论》中提到“阳化气,阴化形”,提示肺气的不足其根源便是肺阳的不足。以“肺阳虚”为基础,发现肺阳虚无力温化寒痰,哮喘之“夙根”由此产生;肺阳虚导致肺卫不固,无法抵御外邪入侵肺腑,诱发哮喘发作;肺阳虚无以化气,无法正常宣发肃降、通调水道,累及脾肾,形成哮喘缓解期的本虚标实之证。由此进一步探讨“肺阳虚”与哮喘的发病认识。

关键词：肺阳虚支气管哮喘阳化气阴成形

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两对边简支另两对边固支组合肋预制底板混凝土双向叠合板的简化塑性设计方法

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湖南科技大学学报（自然科学版） 2024年第1期39卷 45-52页

作者：周盼黄海林黄曙湖南科技大学土木工程学院湖南湘潭411201 湖南省智慧建造装配式被动房工程技术研究中心湖南湘潭411201 长沙市人防工程服务中心湖南长沙410013

目前组合肋预制底板混凝土双向叠合板(双向叠合板)已得到广泛应用.针对双向叠合板设计计算复杂的特点,基于塑性铰线法对两对边简支另两对边固支双向叠合板的设计计算进行了研究,推导出双向叠合板的极限承载力,确定塑性铰线位置,求解极... 详细信息

目前组合肋预制底板混凝土双向叠合板(双向叠合板)已得到广泛应用.针对双向叠合板设计计算复杂的特点,基于塑性铰线法对两对边简支另两对边固支双向叠合板的设计计算进行了研究,推导出双向叠合板的极限承载力,确定塑性铰线位置,求解极限均布荷载和极限弯矩.采用极限平衡法对双向叠合板的极限弯矩求解公式进行了简化分析,得到极限弯矩的简化塑性计算公式.采用简化公式对2个算例进行求解计算,结果表明:对于两对边简支另两对边固支双向叠合板可采用文章的简化公式进行计算,简化后的塑性计算公式计算简便,有利于在工程设计中推广使用.

关键词：双向叠合板组合肋塑性设计两对边简支两对边固支

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市政工程施工安全管理与质量控制研究

现代工程科技 2024年第6期3卷 121-124页

作者：潘洲中海建国际建设咨询集团有限责任公司甘肃兰州730030

为探讨市政工程施工过程中的安全管理与质量控制措施,以提升市政工程施工管理水平,避免因质量安全问题带来经济损失或生命威胁,通过文献综述法,结合市政工程施工方面的实践经验和相关数据,分析市政工程施工质量安全工作的特点及要求,剖... 详细信息

为探讨市政工程施工过程中的安全管理与质量控制措施,以提升市政工程施工管理水平,避免因质量安全问题带来经济损失或生命威胁,通过文献综述法,结合市政工程施工方面的实践经验和相关数据,分析市政工程施工质量安全工作的特点及要求,剖析市政工程施工质量安全的影响要素。深入研究市政工程施工质量安全工作的有效措施,从人员管理、技术管理、物资管理、制度管理、环境管理五个方面提出具体可行的管理措施。最终得出结论,在市政工程施工管理中要重视人员、技术、物资、制度和环境等因素的影响,采取有效措施可提升质量和安全水平,为市政工程施工保驾护航。

关键词：市政工程安全管理质量控制影响因素提升措施

基于射线追踪法的LUNA月球基地通信信道特性分析

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信号处理 2024年第4期40卷 733-746页

作者：杨晋生张振远潘州天津大学微电子学院天津300072 天津航海仪器研究所天津300130

在探月任务中,创建月球基地是一项重要任务。为了满足月球基地获取高清晰度视频和科学数据的高速数据传输需求,以及宇航员和月球探测车等设备支持高容量数据速率通信的需求,需要充分利用太赫兹频段的频谱资源。太赫兹频段的频谱资源相... 详细信息

在探月任务中,创建月球基地是一项重要任务。为了满足月球基地获取高清晰度视频和科学数据的高速数据传输需求,以及宇航员和月球探测车等设备支持高容量数据速率通信的需求,需要充分利用太赫兹频段的频谱资源。太赫兹频段的频谱资源相对较为丰富,可以提供更大的带宽和更快的通信速率。本文以LUNA月球基地为研究对象,采用信道建模的方法,对该场景下的太赫兹频段信道特性进行了仿真和分析。通过对该信道特性的评估,为未来的月球基地通信系统方案设计提供链路等方面的性能评估。首先本文对LUNA月球基地的工作模块和居住模块的构造进行了详细的研究。采用了射线追踪法和单刃形衍射模型的混合建模方法,建立了一种适用于月球基地内近距离通信场景的多射线信道模型。最终推导出了适用于该场景链路的信道容量模型。其次本文对LUNA月球基地的工作模块LUNA大厅和居住模块FLEXHab进行了建模,并借助太赫兹信道模拟器CloudRT进行信道仿真。对信道的大尺度衰落特性和小尺度衰落特性进行了分析。最后为了估算信道容量,采用了注水功率和等功率分配两种不同的分配方式。所提出的信道模型可用于评估太赫兹频段月球基地内通信系统的性能,并对月球基地通信系统的建设提供理论依据和参考。

关键词：月球基地信道建模信道容量射线追踪

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n-exact Categories Arising from n-exangulated Categories

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数学学报:英文版 2023年第9期39卷 1781-1794页

作者： Jian He pan Yue zhou Department of Applied Mathematics Lanzhou University of TechnologyLanzhou730050P.R.China School of Mathematics and Statistics Changsha University of Science and TechnologyChangsha410114P.R.China

Let l be a Krull-Schmidt n-exangulated category and A be an n-extension closed subcategory of *** A inherits the n-exangulated structure from the given n-exangulated category in a natural *** construction gives n-exangulated categories which are neither n-exact categories in the sense of Jasso nor(n+2)-angulated categories in the sense of Geiss-Keller-Oppermann in ***,we also give a sufficient condition on when an n-exangulated category A is an n-exact *** results generalize work by Klapproth and zhou.

关键词： (n+2)-angulated categories n-exact categories n-extension closed subcategories n-exangulated categories