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Pore pressure observation: pressure response of probe penetration and tides

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Acta Oceanologica Sinica 2019年第7期38卷 107-113页

作者： Tao Liu guanli wei Hailei Kou Lei Guo Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266061China College of Engineering Ocean University of ChinaQingdao 266100China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China

Excess pore water pressure is an important parameter that can be used to analyze certain physical characteristics of sediment.In this paper,the excess pore water pressure of subseafloor sediment and its variation with tidal movement was measured following the installation of a wharf in Qingdao,China by using a fiber Bragg grating(FBG)piezometer.The results indicated that this FBG piezometer is effective in the field.The measured variation of excess pore water pressure after installation is largely explained by the dissipation of excess pore water pressure.The dissipation rate can be used to estimate the horizontal consolidation coefficient,which ranged from 1.3×10^–6 m^2/s to 8.1×10^–6 m^2/s.The measured values during tidal phases are associated with the variability of tidal pressure on the seafloor and can be used to estimate the compressibility and the permeability of the sediment during tidal movement.The volume compression coefficient estimated from tidal oscillation was approximately 2.0×10^–11 Pa^–1,which was consistent with the data from the laboratory test.The findings of this paper can provide useful information for in situ investigations of subseafloor sediment.

关键词： pore pressure in situ observation penetration tidal load

Effect of Penetration Rates on the Piezocone Penetration Test in the Yellow River Delta Silt

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Journal of Ocean University of China 2022年第2期21卷 361-374页

作者： ZHANG Jiarui MENG Qingsheng ZHANG Yan FENG Xiuli wei guanli SU Xiuting LIU Tao College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China College of Marine Geosciences Ocean University of ChinaKey Laboratory of Submarine Geosciences and ProspectingQingdao 266100China

Partial drainage often occurs during piezocone penetration testing on Yellow River Delta silt because of its intermediate physical and mechanical properties between those of sand and clay.Yet,there is no accurate understanding for the range of penetra-tion rates to trigger the partial drainage of silt soils.In order to fully investigate cone penetration rate effects under partial drainage condi-tions,indoor 1 g penetration model tests and numerical simulations of cavity expansion at variable penetration rates were carried out on the Yellow River Delta silt.The boundary effect of the model tests and the variation of key parameters at the different cavity ex-pansion rates were analyzed.The 1 g penetration model test results and numerical simulations results consistently indicated that the penetration rate to trigger the partially drainage of typical silt varied at least three orders of magnitude.The numerical simulations also provide the reference values for the penetration resistance corresponding to zero dilation and zero viscosity at any given normalized penetration rate for silt in Yellow River Delta.These geotechnical properties can be used for the design of offshore platforms in Yel-low River Delta,and the understanding of cone penetration rate effects under the partially drained conditions would provide some technical support for geohazard evaluation of offshore platforms.

关键词： Yellow River Delta silt cone penetration rate effects 1g model simulation numerical analysis

Impact of a retrogressive thaw slump on surrounding vegetation communities in the Fenghuoshan mountains,Qinghai-Tibet Plateau

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Research in Cold and Arid Regions 2023年第1期15卷 11-17页

作者： Gang wei LaJia weisai ZiJie Zhou XinNing Wu SiRu Gao ZiTeng Fu QingBai Wu guanli Jiang Environmental Geological Prospecting Bureau of Qinghai Province XiningQinghai 810008China Key Laboratory of Qinghai Environmental Geology XiningQinghai 810008China Qinghai Geological Environment Monitoring Station XiningQinghai 810008China School of Geological Engineering and Geomatics Chang'an UniversityXi'anShaanxi 710054China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China

Under global warming,permafrost around the world is experiencing degradation which is especially so on the Third Pole,the Qinghai-Tibet Plateau(QTP),China.Retrogressive thaw slump(RTS)is one of the thermokarst features caused by rapid degradation of ice rich permafrost,which transforms landforms and threatens infrastructures,and even affects the terrestrial carbon cycle.In this work,vegetation communities surrounding a RTS in the Fenghuoshan Mountains of the interior portion of the Qinghai-Tibet Plateau have been investigated to examine the impact from RTS.This investigation indicates that the occurrence of RTS influences the vegetation community by altering their habitats,especially the soil water content,which forces the vegetation community to evolve in order to adapt to the alterations.In the interior part of RTS where it has been disturbed tremendously,alterations have produced a wider niche and richer plant species.This favors species of a wet environment in a habitat where it was a relatively dry environment of alpine steppe prior to the occurrence of RTS.This study adds to limited observations regarding the impact of RTS to vegetation community on the QTP and helps us to reach a broader understanding of the effects of permafrost degradation as well as global warming.

关键词： Retrogressive thaw slump Vegetation community Rapid permafrost degradation Global warming Qinghai-Tibet plateau

出院准备服务在下肢静脉溃疡患者中的应用效果

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护理与康复 2024年第1期23卷 33-36,42页

作者：王笑笑陈晨王晓玉尉冠丽史云霞河南省人民医院河南郑州450000

目的观察出院准备服务在下肢静脉溃疡患者中的应用效果。方法以2022年10月至12月住院的31例患者对照组,采用常规出院方案;以2023年1月至3月住院的31例患者为干预组,实施出院准备服务方案。采用出院准备度量表、压疮愈合计分量表、再入... 详细信息

目的观察出院准备服务在下肢静脉溃疡患者中的应用效果。方法以2022年10月至12月住院的31例患者对照组,采用常规出院方案;以2023年1月至3月住院的31例患者为干预组,实施出院准备服务方案。采用出院准备度量表、压疮愈合计分量表、再入院率、并发症发生情况评价两组干预效果。结果对照组患者出院准备度得分为(144.58±7.69)分,干预组患者出院准备度得分为(152.87±9.45)分,差异有统计学意义(t=3.788,P<0.001)。干预前后压疮愈合计分量表得分差值对照组为(4.97±1.82)分、干预组为(6.97±2.27)分,差异有统计学意义(t=3.827,P<0.001)。对照组与干预组再入院率分别为25.81%、6.45%,差异有统计学意义(χ^(2)=4.292,P=0.038)。对照组与干预组患者浅静脉炎的发生率分别为16.13%、9.68%,差异无统计学意义(χ^(2)=0.574,P=0.449);活动性出血的发生率分别为9.68%、3.23%,差异无统计学意义(χ^(2)=1.069,P=0.301);继发感染的发生率分别为16.13%、3.23%,差异无统计学意义(χ^(2)=2.952,P=0.086)。结论对下肢静脉溃疡患者实施出院准备服务干预可提高其出院准备水平和伤口愈合效果,降低再入院率,进而改善患者健康结局,但对并发症发生率的效果有待验证。

关键词：下肢静脉溃疡出院准备服务伤口愈合

Cooling mechanism of embankment with block stone interlayer in Qinghai-Tibet railway

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Science China(Technological Sciences) 2007年第3期50卷 319-328页

作者： WU QingBai CHENG HongBin JIANG guanli MA wei LIU YongZhi State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China

In order to study the cooling mechanism of embankment with block stone interlayer under open and closed conditions,an experimental railway section was built and data within one freeze-thaw cycle were collected. The results explain well the cooling mechanism of embankment with block stone interlayer. Under the open condition in cold seasons,the enforced convection effect occurs within block stone interlayer when the wind speed is large;however,the weak air convection occurs within the block stone interlayer near the bottom of the embankment when the wind speed is slow. Under the open condition in warm seasons,heat conduc-tion occurs within block stone interlayer due to the change in wind speed and di-rection. Under the closed condition,however,the enforced convection within block stone interlayer is so weak that heat conduction is dominant in the whole year be-cause wind is blocked. Therefore,the cooling effect of embankment with a block stone interlayer to the soil beneath it is produced by enforced convection and weak free air convection;both its process and the cooling intensity are controlled by the local wind speed and direction. Because of the difference in the cooling effects,the soil temperature beneath the embankment has a temperature difference of 2℃―4℃ between the open and closed conditions.

关键词： Qinghai-Tibet railway embankment with block stone interlayer cooling mechanism enforced convection effect

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炼钢厂10 kV系统直流屏升级改造实践

冶金经济与管理 2024年第1期 52-54页

作者：张伟河钢邯钢邯宝炼钢厂河北邯郸056015

在分析河钢邯钢邯宝炼钢厂直流屏系统升级改造工作开展必要性的基础上,介绍了改造方案设计、改造实施步骤等实践过程,指出改造后炼钢厂自动化运维模式不断优化、设备仪表采购维护减少、蓄电池组运维效率提升,实现站用电源安全化、网络... 详细信息

在分析河钢邯钢邯宝炼钢厂直流屏系统升级改造工作开展必要性的基础上,介绍了改造方案设计、改造实施步骤等实践过程,指出改造后炼钢厂自动化运维模式不断优化、设备仪表采购维护减少、蓄电池组运维效率提升,实现站用电源安全化、网络智能化,更好地发挥了直流屏在炼钢厂供配电系统中的作用。

关键词：直流屏充电模块蓄电池监控系统

不同地表条件下青藏公路对多年冻土的热影响差异研究

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冰川冻土 2022年第2期44卷 470-484页

作者：周保魏刚张永艳魏赛拉加蒋观利青海省地质环境监测总站青海西宁810008 青海省环境地质勘查局青海西宁810008 中国科学院西北生态环境资源研究院冻土工程国家重点实验室甘肃兰州730000

在多年冻土区,道路工程会对周边的多年冻土产生热影响,但不同地表条件下的多年冻土对道路热影响的反馈差异尚不完全清楚。本研究基于青藏公路沿线两处监测场地的多年冻土监测数据,研究了不同地表条件下青藏公路对多年冻土的热影响差异... 详细信息

在多年冻土区,道路工程会对周边的多年冻土产生热影响,但不同地表条件下的多年冻土对道路热影响的反馈差异尚不完全清楚。本研究基于青藏公路沿线两处监测场地的多年冻土监测数据,研究了不同地表条件下青藏公路对多年冻土的热影响差异。结果表明,青藏公路对多年冻土的热影响因地表条件的不同而存在差异。与植被覆盖率较高的监测场地相比,在植被覆盖率较低的监测场地,其多年冻土年平均地温更高、多年冻土活动层厚度更大,且青藏公路对多年冻土的水平热影响范围也相对更大。此外,在植被覆盖率较低的监测场地最靠近坡脚的位置处,由于地表条件的不同,其浅层土壤更易受到外界扰动,导致该位置浅层土壤与外界的热交换特征迥异于其他监测位置,这可能也是导致两处监测场地多年冻土的热状态存在差异的原因。目前,青藏工程走廊内各线性工程密布,工程间的相互影响及其与多年冻土间的关系已成为必须考虑的问题。本研究工作对于青藏高原多年冻土区工程走廊内线性工程之间的合理间距设定,以及即将建设的青藏高速公路双向路基间的合理距离设计都可提供参考,以达到减少工程热扰动,保障工程安全运营的目的。

关键词：多年冻土地表条件青藏公路热影响青藏高原

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上交所首个煤炭重组上市企业经营状况分析

冶金经济与管理 2024年第2期 31-33页

作者：王崇彩魏有文安徽科技学院管理学院安徽蚌埠233000

以上交所首个煤炭重组上市企业为样本,从财务状况为出发点,围绕营业收入、业务结构、应收账款等方面,结合外部竞争环境及其他产业发展变化,分析该企业在未来的竞争环境中如何能够取得有利地位,对其提出未来发展建议,为相关企业的发展提... 详细信息

以上交所首个煤炭重组上市企业为样本,从财务状况为出发点,围绕营业收入、业务结构、应收账款等方面,结合外部竞争环境及其他产业发展变化,分析该企业在未来的竞争环境中如何能够取得有利地位,对其提出未来发展建议,为相关企业的发展提供一定的启示与借鉴。

关键词：煤炭淮北矿业重组上市企业经营状况

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基于高质量发展的钢铁厂总体规划思路

冶金经济与管理 2024年第3期 46-48,52页

作者：李艳艳马业伟中冶赛迪工程技术股份有限公司重庆401122

结合当前我国钢铁行业发展现状,在“产能置换”“环保限产”“煤炭控制”等背景下,对钢铁厂总体规划的思路进行探讨。论述了行业政策环境的影响、企业调研分析的关注点和方法,并从总体规划角度阐述适合钢铁企业发展的规划思路。在钢铁... 详细信息

结合当前我国钢铁行业发展现状,在“产能置换”“环保限产”“煤炭控制”等背景下,对钢铁厂总体规划的思路进行探讨。论述了行业政策环境的影响、企业调研分析的关注点和方法,并从总体规划角度阐述适合钢铁企业发展的规划思路。在钢铁工业高质量发展背景下,钢铁厂总体规划需要结合企业战略定位、发展目标、建设思路、自身优势、限制因素等多方面综合考虑,对钢铁厂进行系统性的规划,助力企业高质量发展,并步入具有竞争优势的发展之路。最后,结合实践,分享开展钢铁厂总体规划工作的体会,以期对同行从业者有所启发。

关键词：高质量发展钢铁厂总体规划