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Overburden fracture evolution laws and water-controlling technologies in mining very thick coal seam under water-rich roof 被引量:8
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作者 Zhang Youxi Tu Shihao +1 位作者 Bai Qingsheng Li Jianjun 《International Journal of Mining Science and Technology》 SCIE EI 2013年第5期693-700,共8页
Considering the danger of water inrush in mining very thick coal seam under water-rich roof in Majialiang Coal Mine,the universal discrete element(UDEC)software was used to simulate the overburden fracture evolution l... Considering the danger of water inrush in mining very thick coal seam under water-rich roof in Majialiang Coal Mine,the universal discrete element(UDEC)software was used to simulate the overburden fracture evolution laws when mining 4#coal seam.Besides,this study researched on the influence of face advancing length,speed and mining height on the height of the water flowing fractured zones(HWFFZ),and analyzed the correlation of face advancing length and change rules of aquifer water levels and goaf water inflow.Based on those mentioned above,this research proposed the following water-controlling technologies:draining the roof water before mining,draining goaf water,reasonable advancing speed and mining thickness.These water-controlling technologies were successfully used in the feld,thus ensured safely mining the very thick coal seam under water-rich roof. 展开更多
关键词 water-rich roof Very thick coal seam Mining induced fracture Evolution law water-controlling technology
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Morphological and molecular response of small intestine to lactulose and hydrogen-rich water in female piglets fed Fusarium mycotoxins contaminated diet 被引量:7
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作者 Xu Ji Qing Zhang +1 位作者 Weijiang Zheng Wen Yao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2019年第3期694-707,共14页
Background: Following the intake of Fusarium mycotoxin-contaminated feed,small intestines may be exposed to high levels of toxic substances that can potentially damage intestinal functions in livestock.It is well know... Background: Following the intake of Fusarium mycotoxin-contaminated feed,small intestines may be exposed to high levels of toxic substances that can potentially damage intestinal functions in livestock.It is well known that Fusarium mycotoxins will lead a breakdown of the normally impeccable epithelial barrier,resulting in the development of a "leaky" gut.H2 administration with different methods has been proved definitely potentials to prevent serious intestinal diseases.The goal of this study is to investigate the roles of lactulose(LAC) and hydrogenrich water(HRW) in preventing intestinal dysfunction in piglets fed Fusarium mycotoxin-contaminated feed.Methods: A total of 24 female piglets were evenly assigned to 4 groups: negative control(NC) group,mycotoxincontaminated(MC) feed group,MC feed with LAC treatment(MC + LAC),and MC feed with HRW treatment(MC +HRW),respectively.Piglets in the NC group were fed uncontaminated control diet,while remaining piglets were fed Fusarium mycotoxin-contaminated diet.For the NC and MC groups,10 mL/kg body weight(BW) of hydrogen-free water(HFW) was orally administrated to piglets twice daily;while in the MC + LAC and MC + HRW groups,piglets were treated with the same dose of LAC solution(500 mg/kg BW) and HRW twice daily,respectively.On d 25,serum was collected and used for biochemical analysis.Intestinal tissues were sampled for morphological examination as well as relative genes and protein expression analysis.Results: Our data showed that Fusarium mycotoxins induced higher serum diamine oxidase(DAO) activities(P < 0.05),D-lactic acid levels(P < 0.01),and endotoxin status(P < 0.01),lower villus height(P < 0.01) and ratio of villus height to crypt depth(P < 0.05) in small intestine,greater apoptosis index and higher mRNA expression related to tight junctions(P < 0.05).In addition,the distribution and down-regulation of claudin-3(CLDN3) protein in the small intestinal was also observed.As expected,oral administrations of HRW and LAC were found to remarkably provide beneficial effects against Fusarium mycotoxin-induced apoptosis and intestinal leaking.Moreover,either HRW or LAC treatments were also revealed to prevent abnormal intestinal morphological changes,disintegrate tight junctions,and restore the expression and distribution of CLDN3 protein in the small intestinal mucosal layer in female piglets that were fed Fusarium mycotoxins contaminated diet.Conclusions: Our data suggest that orally administrations of HRW and LAC result in less Fusarium mycotoxininduced apoptosis and leak in the small intestine.Either HRW or LAC treatments could prevent the abnormal changes of intestinal morphology and molecular response of tight junctions as well as restore the distribution and expression of CLDN3 protein of small intestinal mucosa layer in female piglets that were fed Fusarium mycotoxins contaminated diet. 展开更多
关键词 Fusarium mycotoxins Hydrogen-rich water LACTULOSE PIGLETS Small INTESTINE
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Effects of alkaline-electrolyzed and hydrogen-rich water,in a high-fat-diet nonalcoholic fatty liver disease mouse model 被引量:10
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作者 Karen Jackson Noa Dressler +3 位作者 Rotem S Ben-Shushan Ari Meerson Tyler W LeBaron Snait Tamir 《World Journal of Gastroenterology》 SCIE CAS 2018年第45期5095-5108,共14页
AIM To identify the effect of hydrogen-rich water(HRW) and electrolyzed-alkaline water(EAW) on high-fat-induced non-alcoholic fatty acid disease in mice.METHODS Mice were divided into four groups:(1) Regular diet(RD)/... AIM To identify the effect of hydrogen-rich water(HRW) and electrolyzed-alkaline water(EAW) on high-fat-induced non-alcoholic fatty acid disease in mice.METHODS Mice were divided into four groups:(1) Regular diet(RD)/regular water(RW);(2) high-fat diet(HFD)/RW;(3) RD/EAW; and(4) HFD/EAW. Weight and body composition were measured. After twelve weeks, animals were sacrificed, and livers were processed for histology and reverse-transcriptase polymerase chain reaction. A similar experiment was performed using HRW to determine the influence and importance of molecular hydrogen(H2) in EAW. Finally, we compared the response of hepatocytes isolated from mice drinking HRW or RW to palmitate overload.RESULTS EAW had several properties important to the study:(1) pH = 11;(2) oxidation-reduction potential of-495 mV; and(3) H2 = 0.2 mg/L. However, in contrast to other studies, there were no differences between the groups drinking EAW or RW in either the RD or HFD groups. We hypothesized that the null result was due to low H2 concentrations. Therefore, we evaluated the effects of RW and low and high HRW concentrations(L-HRW = 0.3 mg H2/L and H-HRW = 0.8 mg H2/L, respectively) in mice fed an HFD. Compared to RW and L-HRW, H-HRW resulted in a lower increase in fat mass(46% vs 61%), an increase in lean body mass(42% vs 28%), and a decrease in hepatic lipid accumulation(P < 0.01). Lastly, exposure of hepatocytes isolated from mice drinking H-HRW to palmitate overload demonstrated a protective effect from H2 by reducing hepatocyte lipid accumulation in comparison to mice drinking regular water.CONCLUSION H2 is the therapeutic agent in electrolyzed-alkaline water and attenuates HFD-induced nonalcoholic fatty liver disease in mice. 展开更多
关键词 Hydrogen-rich-water NONALCOHOLIC fatty liver disease ALKALINE water Metabolic syndrome Molecular HYDROGEN HIGH-FAT DIET
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Study on the Possibility of Mixed Water as a Drinking Water<br/>—From the Viewpoint of the Formation of Hydrogen-Rich Water 被引量:1
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作者 Akira Hiratsuka Yoshiro Yasuda 《Journal of Water Resource and Protection》 2021年第1期44-73,共30页
In exploring an autonomous independent water supply system, authors have realized the importance of the sustainable water supply utilizing regional features in isolated islands. This paper is further study from the pr... In exploring an autonomous independent water supply system, authors have realized the importance of the sustainable water supply utilizing regional features in isolated islands. This paper is further study from the previous one. This time we have narrowed down the mixing rate of mixed water. In this study, the mixed water less than 0.74% (blood concentration) has been prepared first, and then divided it into five kinds of the mixing rate of mixed water. And we have compared and examined the characteristics of the mixed water from the viewpoint of the relationship between salinity and pH, ORP and that of Dissolved Hydrogen, and examined the possibility of mixed water as a drinking water. As a result, we have obtained the new findings that suggest the possibility. 展开更多
关键词 Seawater RAINwater Hydrogen-rich water Magnesium (Mg2+) Food Additives
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A preliminary study on the spatial distribution characteristics and causes of strontium-rich mineral water in the Dushan complex 被引量:2
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作者 MA Bai-heng LIU Shuo +3 位作者 WANG Xin-zhou ZHAI Xing LI Hong-chao LI Chen-xi 《Journal of Groundwater Science and Engineering》 2018年第2期115-125,共11页
The mountain rocks in the Dushan Complex are Sr-rich granite with a much higher Sr level than those in other crustal lithospheres in eastern China. That presents a high potential for developing Sr-rich mineral water. ... The mountain rocks in the Dushan Complex are Sr-rich granite with a much higher Sr level than those in other crustal lithospheres in eastern China. That presents a high potential for developing Sr-rich mineral water. In this study, 6 groups of rock samples, together with 30 groups of water samples, were collected. Combining with the existing data, the Sr contents in three different types of underground water were obtained, which are the Quaternary pore water, the meshed bedrock fissure water in weathered zones and the tectonic bedrock fissure water. On the basis of preliminary understanding for the distribution characteristics of Sr-rich mineral water in the Dushan Mountain region, the causes for the Sr-rich mineral water were investigated. Our results showed that the Sr content of the rocks in the studied area ranges from 988 to 1 950 μg/g. In the horizontal direction, those in both the pore water and the meshed bedrock fissure water in weathered zones show high values in the west but low ones in the east, and high ones in the south but low ones in the north. Furthermore, both types of water meet the standard for Sr-rich mineral water in the western areas. In the vertical direction, the Sr content shows the lowest value in pore water(the average value is 0.707 mg/L), middle value in the meshed bedrock fissure water in weathered zones(the average value is 1.415 mg/L) and the highest value in the tectonic bedrock fissure water(the average value is 8.331 mg/L). It was thought that the widely-developed Sr-rich granite in this region provides physical sources for the formation of Sr-rich mineral water. The continuous dissolution of Sr during underground water runoff is the internal mechanism. In addition, the hydraulic interrelations may exist between the three vertical aquifers, leading a continuous accumulation of the Sr level during infiltration. 展开更多
关键词 Dushan complex Sr-rich granite Sr-rich mineral water
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Application of 3-D Parallel Electrical Technology Detecting the Water-Rich Areas
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作者 Xuan Wang Liquan Guo 《Open Journal of Geology》 2014年第10期518-523,共6页
Coal working face is damaged more and more seriously by water below the coal face floor. Therefore, floor water detection is a must in the process of extraction. This article aims to introducing application and princi... Coal working face is damaged more and more seriously by water below the coal face floor. Therefore, floor water detection is a must in the process of extraction. This article aims to introducing application and principle of the two-gateways parallel 3-D electrical technology and the arrangement of the observation system. The authors use this method to detect the water under the floor of a mine in north of Anhui. The results show that the two-gateways parallel 3-D electrical technology can accurately locate the water-rich areas, providing the basis for drilling drainage and grouting construction. 展开更多
关键词 The Two-Gateways PARALLEL 3-D Electrical Technology Coal Face FLOOR water-rich Areas
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Effects of natural mineral-rich water consumption on the expression of sirtuin 1 and angiogenic factors in the erectile tissue of rats with fructose-induced metabolic syndrome 被引量:2
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作者 Cidalia D Pereira Milton Severo +2 位作者 Luisa Rafael Maria Joao Martins Delminda Neves 《Asian Journal of Andrology》 SCIE CAS CSCD 2014年第4期631-638,共8页
Consuming a high-fructose diet induces metabolic syndrome (MS)-Iike features, including endothelial dysfunction. Erectile dysfunction is an early manifestation of endothelial dysfunction and systemic vascular diseas... Consuming a high-fructose diet induces metabolic syndrome (MS)-Iike features, including endothelial dysfunction. Erectile dysfunction is an early manifestation of endothelial dysfunction and systemic vascular disease. Because mineral deficiency intensifies the deleterious effects of fructose consumption and mineral ingestion is protective against MS, we aimed to characterize the effects of 8weeks of natural mineral-rich water consumption on the structural organization and expression of vascular growth factors and receptors on the corpus cavernosum (CC) in 10% fructose-fed Sprague-Dawley rats (FRUCT). Differences were not observed in the organization of the CC either on the expression of vascular endothelial growth factor (VEGF) or the components of the angiopoietins/Tie2 system. However, opposing expression patterns were observed for VEGF receptors (an increase and a decrease for VEGFR1 and VEGFR2, respectively) in FRUCT animals, with these patterns being strengthened by mineral-rich water ingestion. Mineral-rich water ingestion (FRUCTMIN) increased the proportion of smooth muscle cells compared with FRUCT rats and induced an upregulatory tendency of sirtuin I expression compared with the control and FRUCT groups. Western blot results were consistent with the dual immunofluorescence evaluation. Plasma oxidized low-density lipoprotein and plasma testosterone levels were similar among the experimental groups, although a tendency for an increase in the former was observed in the FRUCTMIN group. The mineral-rich water-treated rats presented changes similar to those observed in rats treated with MS-protective polyphenol-rich beverages or subjected to energy restriction, which led us to hypothesize that the effects of mineral-rich water consumption may be more vast than those directly observed in this study. 展开更多
关键词 ANGIOPOIETINS erectile tissue hypersaline sodium-rich naturally sparkling mineral water receptors sirtuin 1 vascularendothelial growth factor
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软弱富水地层超大直径盾构下穿长江堤防变形分析
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作者 江浩 刘武 +4 位作者 程锦 尚金行 李仁杰 王立波 姚华彦 《科学技术与工程》 北大核心 2024年第27期11842-11850,共9页
软弱富水地层上长江堤防变形受浅埋超大直径盾构隧道施工扰动影响大。以盾构开挖直径为15.07 m的某双线隧道工程为背景,基于现场监测资料,研究盾构过堤时无为长江堤防沉降的时空演化规律,并对掘进参数与堤防加固措施的合理性进行分析。... 软弱富水地层上长江堤防变形受浅埋超大直径盾构隧道施工扰动影响大。以盾构开挖直径为15.07 m的某双线隧道工程为背景,基于现场监测资料,研究盾构过堤时无为长江堤防沉降的时空演化规律,并对掘进参数与堤防加固措施的合理性进行分析。研究结果表明,压密注浆加固处理可有效减小堤防地表沉降幅度。右线隧道过堤时,中轴线上方堤防沉降变形总体随着盾尾离开天数的增加而增大,最大沉降位于堤前段,为20.37 mm,远离中轴线部位普遍产生轻微隆起。左线隧道下穿堤防后,堤防竖直变形整体呈“左线堤前段与堤后段隆起、堤坝段沉降,右线整体沉降,幅度从堤前段往堤后段沉减小”的分布规律。盾构下穿长江堤防时,切口压力、推力、扭矩等掘进参数的调整受堤坝超载效应影响。 展开更多
关键词 富水地层 盾构隧道 掘进参数 长江堤防 沉降规律
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富水裂隙围岩隧道涌水量计算方法与规律分析
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作者 傅鹤林 安鹏涛 +2 位作者 伍毅敏 李鲒 陈龙 《哈尔滨工业大学学报》 EI CAS CSCD 北大核心 2024年第3期110-116,共7页
富水裂隙区隧道涌水量预测精度较差,涌水问题尚未得到较好的解决。针对此问题,视裂隙围岩及注浆区为非均质各向异性介质,初期支护及二次支护结构为均质各向同性介质,构建了裂隙围岩下隧道涌水简化计算模型,基于地下水力学理论及流体质... 富水裂隙区隧道涌水量预测精度较差,涌水问题尚未得到较好的解决。针对此问题,视裂隙围岩及注浆区为非均质各向异性介质,初期支护及二次支护结构为均质各向同性介质,构建了裂隙围岩下隧道涌水简化计算模型,基于地下水力学理论及流体质量守恒定律推导了富水裂隙区隧道涌水量计算公式。通过退化分析及案例工程现场实测数据验证了构建富水裂隙区隧道涌水简化计算模型的合理性及涌水量计算式求解的正确性,最后基于解析解揭示了各特征参数对富水裂隙区隧道涌水的影响规律,探讨了富水裂隙区隧道涌水机制。结果表明:理论计算值与现场实测值最大相对误差为8.1%,验证了构建模型的合理性及公式推导的正确性;隧道涌水量随裂隙最大宽度的增加而增大,受堵水结构的联合制约,两者近似呈线性关系;注浆区厚度与隧道半径比值在2倍以内时,隧道涌水量受注浆区厚度的影响显著;富水裂隙区隧道涌水受裂隙分布规律及支护结构的制约,应重视对裂隙分布的调查。 展开更多
关键词 富水裂隙 涌水量 注浆加固 涌水灾害 支护结构
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Efficacy and tolerability of hydrogen carbonate-rich waterfor heartburn
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作者 andré-michael beer ralf uebelhack ute pohl 《World Journal of Gastrointestinal Pathophysiology》 CAS 2016年第1期171-180,共10页
AIM To investigate the efficacy and safety of mineralwater with a high content of hydrogen carbonate inpatients with heartburn.METHODS: This open, single-center, single-armclinical pilot study enrolled 50 patients, 1... AIM To investigate the efficacy and safety of mineralwater with a high content of hydrogen carbonate inpatients with heartburn.METHODS: This open, single-center, single-armclinical pilot study enrolled 50 patients, 18-64 yearsold, who had been suffering from heartburn at leasttwice a week for at least 3 mo before entering thestudy. Pharmacological treatment of heartburn was notpermitted, and patients with severe organic diseaseswere excluded. After a run-in period of one week, theparticipants received 1.5 L of the test water for thefollowing 6 wk; 300 mL with meals t.i.d., the remainderto be drunk throughout the day. During the trial, therewere five visits at the study center (screening, baseline,two interim visits and the final visit). The efficacyendpoints included incidence and duration of heartburnepisodes per week by patient's self-assessment (heartburndiary) as well as changes in symptom severity asper symptom specific questionnaires [Reflux Disease Questionnaire (RDQ); Quality of Life in Reflux andDyspepsia (QOLRAD); Gastrointestinal Quality of LifeIndex] and overall health-related quality of life per SF-12(12-question short form) at each visit. At the end of thestudy, patients and investigators independently ratedthe overall efficacy of the test water on a 4-point Likertscale. Safety was assessed by evaluation of adverseevents (AEs), vital signs (heart rate, blood pressure)and laboratory parameters. Changes from initial to finalexaminations were assessed by the non-parametricWilcoxon test; categorical variables were comparedusing the χ 2 test, and for more than 5 categories, by theU-test.RESULTS: Twenty-eight participants were men, 22women. The mean age of the patients in the fullanalysis set/intention-to treat population (FAS/ITT) was40.6 years. Forty-two participants completed the studyaccording to the study protocol and formed the perprotocolset (PP population); 48 participants drank thewater at least once as requested and were analyzedas ITT population. The occurrence of heartburn wasstatistically significantly reduced at wk 6 in both the ITTand the PP populations. At wk 6, the mean number ofheartburn episodes/week decreased by 5.1 episodes(P 〈 0.001) and the mean duration of heartburnsymptoms by 19 min (ITT) (P = 0.002). The frequencyof heartburn symptoms was reduced in 89.6% of thepatients (P 〈 0.001), and the duration of symptoms in79.2% of patients (ITT) (P 〈 0.001). All dimensions ofthe RDQ (heartburn, regurgitation, gastro-esophagealreflux disease symptoms, dyspepsia) showed asignificant improvement at 6 wk. Likewise, diseasespecificquality of life improved significantly (QOLRAD,GIQLI). Overall, 89.4% of patients rated the efficacyof the test water as "good" or "very good", as did theinvestigators for 91.5% of the patients. There wereno serious AEs. After 6 wk, systolic and diastolic bloodpressure values decreased slightly but significantly [-3.5and -3.0 mmHg, respectively (P = 0.008 and P = 0,002)].Ninety-six percent of patients and investigators for thesame percentage of patients rated the tolerability of thewater as "good" or "very good".CONCLUSION: The data demonstrate effectiveness ofa hydrogen carbonate-rich mineral water in alleviatingheartburn frequency and severity, thereby improvingquality of life. The water has excellent tolerability. 展开更多
关键词 HEARTBURN HYDROGEN carbonate-rich mineralwater Open clinical pilot study Patients REGURGITATION Gastroesophageal reflux disease symptoms Dyspepsia Blood pressure TOLERABILITY Quality of life
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基于SVM的富水岩溶区双线盾构隧道下穿既有线临界安全距离研究
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作者 侯艳娟 赵继 +5 位作者 娄在明 章哲滔 孙振宇 杨阳 茹振华 李念祖 《铁道标准设计》 北大核心 2024年第9期121-131,139,共12页
双线盾构隧道在极复杂的岩溶地质中下穿既有线施工时,会对地层造成较大扰动,从而增加既有地表沉降过大或坍塌的风险,严重威胁既有线的运营安全。同时,隧道穿越富水岩溶区域时,需要保持一定距离以避免与溶洞相交,确保双线盾构隧道围岩的... 双线盾构隧道在极复杂的岩溶地质中下穿既有线施工时,会对地层造成较大扰动,从而增加既有地表沉降过大或坍塌的风险,严重威胁既有线的运营安全。同时,隧道穿越富水岩溶区域时,需要保持一定距离以避免与溶洞相交,确保双线盾构隧道围岩的稳定性。利用FlAC^(3D)软件建立不同工况组合下双线盾构隧道与左侧溶洞的临界安全距离数值模型,分析不同地下水位对既有线沉降和围岩塑性区范围的影响,并采用正交试验和多元线性回归方法建立双线盾构隧道在不同围岩等级、地下水埋深、开挖隧道埋深和溶洞孔径组合下与溶洞的临界安全距离计算公式。此外,还基于SVM模型对正交试验结果进行机器学习,得到可以预测岩溶地区双线盾构隧道临界安全距离的智能预测系统,实现双线盾构隧道下穿既有线临界安全距离的非线性智能预测。结果表明:当地下水位位于既有线以上时,其水位越高,既有线的沉降量越大、围岩塑性区范围越大,地下水对盾构隧道与溶洞的临界安全距离有很大影响,应用SVM模型和多元线性回归方法确定双线盾构隧道与溶洞之间的临界安全距离是行之有效的。 展开更多
关键词 富水岩溶区 双线盾构隧道 正交试验 多元线性回归 SVM模型 临界安全距离
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基于水平旋喷桩处置优化的地铁隧道施工变形控制分析
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作者 王立新 高洋 +2 位作者 汪珂 李储军 邱军领 《河北工程大学学报(自然科学版)》 CAS 2024年第1期52-61,共10页
为研究富水砂层隧道中水平旋喷桩+超前小导管组合预加固的效果,以青岛地铁某区间段隧道为依托,采用有限元数值模拟方法,对比分析了无预加固、单独使用水平旋喷桩及旋喷桩配合超前小导管组合预加固三种工况的加固效果。结果表明,与无预... 为研究富水砂层隧道中水平旋喷桩+超前小导管组合预加固的效果,以青岛地铁某区间段隧道为依托,采用有限元数值模拟方法,对比分析了无预加固、单独使用水平旋喷桩及旋喷桩配合超前小导管组合预加固三种工况的加固效果。结果表明,与无预加固方案相比,单独使用水平旋喷桩预加固可使地表沉降、拱顶沉降、掌子面纵向位移分别相应减少约61%、59%、38%;而水平旋喷桩与超前小导管组合预加固方案可使地表沉降、拱顶沉降、掌子面纵向位移分别相应减少约66%、77.6%、38.9%,典型开挖断面处与拱脚处地下水渗流量分别减少93.4%、96.7%,预加固效果与止水效果显著。 展开更多
关键词 水平旋喷桩 富水砂层 数值模拟 止水效果 预加固
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富水砂层地铁盾构区间机械法联络通道施工影响
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作者 杜明芳 张鹏 +5 位作者 易领兵 任方毅 邵奇 肖中圣 朱行通 李俊昊 《城市轨道交通研究》 北大核心 2024年第7期88-92,共5页
[目的]目前,富水砂层地铁盾构区间机械法联络通道施工对正线隧道及周围土体影响的研究较少,因此有必要对类似工程进行分析。[方法]以某富水砂层地铁盾构区间机械法联络通道施工项目为例,采用ABAQUS有限元软件建立数值模型,对富水砂层中... [目的]目前,富水砂层地铁盾构区间机械法联络通道施工对正线隧道及周围土体影响的研究较少,因此有必要对类似工程进行分析。[方法]以某富水砂层地铁盾构区间机械法联络通道施工项目为例,采用ABAQUS有限元软件建立数值模型,对富水砂层中机械法联络通道施工的全过程进行模拟分析,研究机械法联络通道施工对正线隧道及周围土体的影响;将数值计算结果与实际工程监测数据进行对比,验证所提数值模型的可靠性。[结果及结论]由机械法联络通道施工引起的沿正线隧道纵向和联络通道纵向的地面沉降曲线均呈U形,地面最大沉降值为4.60 mm;机械法联络通道施工对正线隧道的变形影响,以竖向变形和沿正线隧道横向的水平变形为主,正线隧道竖向变形最大值为1.08 mm,水平变形最大值为1.28 mm;施工过程中,正线隧道的最大应力会随着联络通道洞门的破除而突然增大,施工完成时,正线隧道的最大应力值为52.54 MPa。实际监测数据表明,拟合后的地面沉降监测数据与数值计算结果的变化趋势一致,验证了数值计算的可靠性。 展开更多
关键词 地铁 联络通道 富水砂层 机械法施工
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隧道富水断层破碎带突涌预报与工程对策研究
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作者 林之恒 袁东 徐正宣 《铁道标准设计》 北大核心 2024年第9期113-121,共9页
为解决高原隧道断层破碎带易发突泥冒顶灾害的问题,采用现场调查、地面物探、洞内地震波反射法、瞬变电磁法、超前钻孔等超前地质预报方法,推广洞内物探三维分析,对富水断层破碎带突泥灾害特征、超前地质预报综合成果和工程应对加固措... 为解决高原隧道断层破碎带易发突泥冒顶灾害的问题,采用现场调查、地面物探、洞内地震波反射法、瞬变电磁法、超前钻孔等超前地质预报方法,推广洞内物探三维分析,对富水断层破碎带突泥灾害特征、超前地质预报综合成果和工程应对加固措施进行研究。结果表明:三维物探成果能快速精准查明富水破碎带空间形态,成果直观,有效指导风险判识和工程处置措施;对富水断层带预报应充分结合勘察期成果,宏观初判断层分布特性,洞内采用物钻结合、长短结合的方法;首次提出按照“探明破碎带规模形态,查明破碎带物质组分性状,观测地下水特征变化情况”的思路,研判突泥涌水风险;施工处置应按照“探泄结合,先固后进,回堵再泄”的总体原则有序开展。研究成果和手段可为类似突涌灾害超前地质预报和工程应对措施提供参考。 展开更多
关键词 高原隧道 富水断层破碎带 突涌预报 物探三维分析 超前地质预报 工程对策
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富水砂层地铁盾构隧道渣土混合改良的流塑性与渗透性
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作者 郑选荣 刘莹 +4 位作者 丁鹏程 李鹏 郭峰 陆宏朝 李军锋 《城市轨道交通研究》 北大核心 2024年第3期37-42,共6页
[目的]盾构在富水砂层中掘进时,易产生刀盘扭矩过高、磨损严重以及螺旋运输机喷涌等问题。为了保证施工的安全性,需对渣土进行改良。[方法]以西安地铁16号线某盾构区间工程为依托,根据砂土地层自稳性差、摩擦性高、渗透率高的特点选取... [目的]盾构在富水砂层中掘进时,易产生刀盘扭矩过高、磨损严重以及螺旋运输机喷涌等问题。为了保证施工的安全性,需对渣土进行改良。[方法]以西安地铁16号线某盾构区间工程为依托,根据砂土地层自稳性差、摩擦性高、渗透率高的特点选取渣土改良剂。通过渣土坍落度试验、渗透试验、现场试验相结合的方式,采用泡沫单独改良、泡沫及膨润土泥浆混合改良两种方案开展富水砂层渣土改良试验研究。[结果及结论]实际盾构掘进施工中,在考虑安全、高效、经济的前提下,结合室内试验所得数据,确定采用膨润土泥浆、泡沫混合改良的方案。当膨润土与水质量比为1/8,发泡液质量分数为3%时,改良剂性能满足施工要求;泡沫单独改良渣土受含水率影响大,含水率越高,泡沫最佳注入率越小。中砂的最佳改良方案是BIR(膨润土泥浆注入比)为10%,FIR(泡沫注入率)为20%~25%;砾砂的最佳改良方案是BIR为10%,FIR为35%~40%。工程实践表明,渣土混合改良效果良好,盾构掘进参数平稳。 展开更多
关键词 地铁 盾构隧道 渣土混合改良 流塑性 渗透性 富水砂层
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富水砂层中盾构始发穿越既有地铁线路的结构稳定性研究
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作者 麻凤海 张强强 《城市轨道交通研究》 北大核心 2024年第4期150-154,共5页
[目的]富水砂层地质条件下,新建地铁线路盾构始发穿越既有地铁线路时,对既有地铁线路结构稳定性的研究较为鲜见,需总结类似工程的相关规律。[方法]以新建的郑州地铁7号线黄河迎宾馆站—英才街站区间盾构始发穿越既有地铁2号线结构工程... [目的]富水砂层地质条件下,新建地铁线路盾构始发穿越既有地铁线路时,对既有地铁线路结构稳定性的研究较为鲜见,需总结类似工程的相关规律。[方法]以新建的郑州地铁7号线黄河迎宾馆站—英才街站区间盾构始发穿越既有地铁2号线结构工程为依托,根据实际工况采用有限元软件MIDAS GTS NX建立了施工区间的三维数值模型,并利用软件的结果提取功能得到了该工程对应模型的模拟结果。选取现场2个监测点位,将2个测点的现场实测值与模拟计算值进行对比,证实了该模型的准确性。在此基础上,进一步研究了盾构始发穿越、一般下穿施工两种穿越方式下对既有地铁线路结构稳定性的影响,以及始发洞门与既有地铁结构间竖向距离d的4个取值对既有地铁线路结构稳定性的影响。[结果及结论]所建三维模型在一定程度上可反映实际工况。在既有地铁线路结构、材料、加固方式等因素均不变的情况下,既有地铁线路结构的稳定性因穿越方式的不同而有所差异,与一般下穿施工相比,采用盾构始发下穿方式时对既有地铁线路结构的影响较小。采用盾构始发下穿方式时,d的取值不同,对既有地铁线路结构稳定性的影响有较大差异。d=2.00 m对既有地铁线路结构的影响较小,工程成本也较小。建议在工程条件允许下采用盾构始发下穿方式,且推荐d值取2.00 m。 展开更多
关键词 地铁 盾构施工 富水砂层 盾构始发穿越 结构稳定性
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岩溶地层地铁车站深基坑渗漏灾害成因分析
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作者 王祥秋 陈世超 肖莹萍 《城市轨道交通研究》 北大核心 2024年第9期115-120,共6页
[目的]富水岩溶深基坑施工开挖常发生基坑侧壁或底部突涌灾害问题,应针对富水溶洞地层深基坑开挖时的渗流稳定性进行深入研究。[方法]依托佛山地铁3号线中山公园站深基坑开挖工程,对深基坑渗流特性及坑底涌水机理进行深入研究,建立了基... [目的]富水岩溶深基坑施工开挖常发生基坑侧壁或底部突涌灾害问题,应针对富水溶洞地层深基坑开挖时的渗流稳定性进行深入研究。[方法]依托佛山地铁3号线中山公园站深基坑开挖工程,对深基坑渗流特性及坑底涌水机理进行深入研究,建立了基坑-土体-溶洞三维数值模型,采用等效渗透系数法对岩溶-地层渗流场进行耦合模拟。[结果及结论]通过仿真模拟分析,获得了不均匀地层中岩溶区富水程度对基坑渗流场及涌水量的影响规律,阐明了基坑底部土体竖向平均水力坡降演变特性,揭示了该地岩溶区基坑底部突涌水机理,研究结果可为富水岩溶地区深基坑工程的设计与施工提供参考。 展开更多
关键词 地铁车站深基坑 富水岩溶地层 突涌灾害机理 数值模拟
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基于序关系分析—独立性权系数法的含水层富水性研究
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作者 代革联 刘凯 +5 位作者 牛超 李林 王超 许鑫 赵瑞平 刘路路 《能源与环保》 2024年第10期1-6,20,共7页
为评价冯家塔煤矿4煤顶板山西组砂岩含水层富水性,选取了山西组富水砂岩厚度、岩心采取率、砂泥岩互层层数、脆塑性岩厚度比、砂岩岩性系数5个影响因素,利用序关系分析法求出影响山西组砂岩含水层富水性的主观权重,利用独立性权系数法... 为评价冯家塔煤矿4煤顶板山西组砂岩含水层富水性,选取了山西组富水砂岩厚度、岩心采取率、砂泥岩互层层数、脆塑性岩厚度比、砂岩岩性系数5个影响因素,利用序关系分析法求出影响山西组砂岩含水层富水性的主观权重,利用独立性权系数法求出客观权重,采用乘法合成法得出综合权重,构建了富水性评价模型。结果表明,冯家塔4煤顶板山西组砂岩含水层富水性较强和强富水区域主要分布在井田南部和西部,弱富水区域主要在井田北部及中部小部分区域。通过对比矿井物探、井下积水区及抽水试验的结果,预测模型准确率较高,与实际情况相符。 展开更多
关键词 冯家塔煤矿 砂岩含水层 富水性 序关系分析 独立性权系数法
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富水岩溶地区隧道涌水预测与施工处置技术研究
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作者 杨洪 田娇 +3 位作者 欧阳淋旭 欧雪峰 张学民 曾晓辉 《建筑技术》 2024年第9期1090-1093,共4页
针对贵州某隧道施工过程中遭遇一处连通地下暗河的大型溶洞引起隧道内大规模涌水的灾害进行研究,结合水文地质情况对涌水量进行预测和分析后,现场先对岩溶水进行初步释压,后采用水泥砂浆分步回填隧道上伏溶腔以封堵岩溶出水口;进一步采... 针对贵州某隧道施工过程中遭遇一处连通地下暗河的大型溶洞引起隧道内大规模涌水的灾害进行研究,结合水文地质情况对涌水量进行预测和分析后,现场先对岩溶水进行初步释压,后采用水泥砂浆分步回填隧道上伏溶腔以封堵岩溶出水口;进一步采用集水管引排岩溶水的方式对剩余地下水进行二次加强处理,同时将集水管与隧道外侧的泄水洞相连,二者构成一套完整的引排水系统的处治手段。采用堵排相结合的原则有效地达到涌水处置目的,确保了隧道的安全施工,可为类似地层的隧道施工提供有益的借鉴。 展开更多
关键词 隧道工程 富水岩溶 涌水量预测 溶洞溶腔
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长江流域建立水资源刚性约束制度的关键问题与对策研究
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作者 许继军 吴江 《中国水利》 2024年第9期34-38,共5页
南方丰水地区建立水资源刚性约束制度,是为了更好地促进生态环境高水平保护和经济社会高质量发展。基于长江流域水资源开发利用、管理现状及特点,分析了长江流域建立水资源刚性约束制度需重点研究的关键问题,并从水资源和水环境承载能... 南方丰水地区建立水资源刚性约束制度,是为了更好地促进生态环境高水平保护和经济社会高质量发展。基于长江流域水资源开发利用、管理现状及特点,分析了长江流域建立水资源刚性约束制度需重点研究的关键问题,并从水资源和水环境承载能力、用水定额标准、计量监测、水资源规划论证、监管考核和市场机制等方面,提出长江流域建立水资源刚性约束制度的对策建议。 展开更多
关键词 水资源刚性约束 水资源环境承载能力 长江流域 丰水地区
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