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1.
地下换热器是地源热泵系统的技术关键,地下换热器换热能力的大小直接影响地源热泵系统的效能,而换热孔灌浆材料导热性能的优良决定着换热器的换热效果。本文在线源理论和热阻网络分析法的基础上建立了钻孔内部换热的传热模型,并在该模型的基础上,研制了一套实验装置,模拟现场条件进行灌浆材料导热性能的实验研究。实验结果表明:水泥基灌浆材料较膨润土基灌浆材料具有更高的热传导系数,且热传导系数都具有随石英砂含量增大而增大的趋势;对水泥基灌浆材料,热传导系数随砂灰比和水灰比的变化而变化。  相似文献   

2.
砾钢渣抗液化特性试验研究   总被引:1,自引:0,他引:1  
陈化的钢渣作为土工回填材料是废弃钢渣循环利用的主要途径之一。按土的工程分类方法,将废弃钢渣划分为砾钢渣、粗钢渣和细钢渣。针对砾钢渣,考虑固结应力比、振动频率、围压和含砾量等影响因素开展动三轴试验研究。分析了砾钢渣的应力、应变和动孔隙水压力的特性,分析了砾钢渣试样的动强度与振动次数、动应变与振动次数、孔隙水压力与振动次数和动应力与动应变关系。采用Seed和Finn提出的饱和砂土动孔压计算模型分析砾钢渣的动孔压曲线类型,并与传统砂砾土的抗液化强度进行比较。得出砾钢渣的抗液化特性较好,工程中可以用砾钢渣替代传统的砂土、砂砾土、砂砾料和砂卵石作为回填料,解决砂砾资源日渐短缺的问题。  相似文献   

3.
砂土混合材料导热性能的试验研究   总被引:5,自引:0,他引:5  
基于平板探针原理,研究了砂和膨润土及其与水泥混合材料的导热性能,对其中各种物质组成情况、时间以及不同温度对导热性能的影响进行了详细分析,得到了导热系数随各种影响因素而变化的曲线。试验结果表明:膨润土单独与水的混合材料导热性能比较差,应与水泥、砂混合。混合材料的导热系数随水灰比(w/c)的减小而增加;加入大颗粒的骨料对于提高导热系数是有效的,即在混合材料中增加含砂量可以使导热系数往往呈增长趋势。  相似文献   

4.
针对富水破碎地层注浆治理过程中传统水泥类材料难以实现注浆加固和堵水同步进行的难题,以硫铝酸盐水泥熟料和钢渣微粉为主要原材,成功制备了一种水泥基复合注浆材料(CGM)。通过与传统水泥材料进行性能对比试验,采用扫描电镜和X射线测试手段,分析了CGM材料制备工艺、组分含量和浆液制备条件对材料性能的作用规律,并检验了CGM材料的工程适用性。结果表明:CGM材料宜采用混合粉磨制备工艺,可显著提高其水化活性,且粉磨时间应不超过45 min。钢渣微粉含量越高,水灰比越大,结石体强度越低,凝结时间越长,水灰比超过1.2:1时,结石体后期会出现干缩。与传统水泥材料相比,CGM材料浆液凝结时间与黏度的环境敏感度低,具有显著的工程适用性和性能优越性。  相似文献   

5.
超细全尾砂材料胶凝成岩机理试验   总被引:4,自引:0,他引:4  
矿山充填是保护土地资源、生态环境,实现矿山无废开采和消除重大安全隐患的理想途径。以某矿全尾砂为试验材料,在分析该矿全尾砂材料的化学成分、粒径级配组成等基本物理、化学特性基础上,借助XRD能谱分析和电镜扫描(SEM)方法,得到不同条件下的超细全尾砂材料胶凝成岩微观规律。对比以水泥、固结剂1#和固结剂2#分别为胶结剂时充填体的强度结果表明,在灰砂配比、浓度和龄期相同的条件下3种胶结材料充填体的强度大小为:固结剂1#>固结剂2#>水泥;固结剂1#可替代水泥作为矿山全尾砂胶结充填的胶结剂,且价格比水泥便宜,有利于降低矿山充填成本。对不同条件下的充填体强度曲线进行拟合,得到充填体的单轴抗压强度增长规律:在养护龄期28 d之内,充填体单轴抗压强度增长规律随龄期变化基本相同,皆遵循指数函数曲线增长规律;当以固结剂1#、2#分别作为胶结材料时,强度增长规律与水泥为胶结剂时相同;强度增长曲线趋势与灰砂配比、料浆浓度以及养护龄期正相关。  相似文献   

6.
袁俊航  隆威 《探矿工程》2015,42(8):71-74
以28天最优配方激发酸性矿渣粉为胶凝材料进行试验,分析了质量浓度、灰砂比、减水剂掺量、搅拌时间4个因素对砂浆流动度、失水率、干缩率、抗压强度的影响规律,并且针对灰砂比这一因素将水泥与矿渣粉胶凝材料浆液性能进行了对比。最后选取了合适的比例进行正交试验来优化各因素组合,使砂浆综合性能达到最优。  相似文献   

7.
我队为了解决钻孔坍塌、掉块,漏水、涌水问题,对“711”型水泥速凝剂进行了护壁堵漏的试验研究工作。现介绍于下。一配比试验在水灰比为0.4的水泥浆中掺入2.5~3.5%(重量比)的“711”速凝剂可在10分钟内凝固,早期强度有提高,28天强度为不掺速凝剂水泥强度的85%。影响凝固时间及强度的主要因素是: 1.掺量当水灰比不变时,“711”的掺量少,初凝时间长,结石体强度高;“711”掺量多,初凝时间短,但掺量不宜过多,以免影响水泥的后期强度,甚至会延长其凝固时间。“711”的适宜掺量应为水泥重量的2.5~3.5%。 2.水灰比“711”的掺量一定时,水灰比大,初凝时间长,结石体强度低;水灰  相似文献   

8.
针对隧道突水灾害防治对注浆材料的特殊要求,在水泥浆中加入外掺剂改善其力学特性与抗冲刷特性。通过测试不同水灰比、纤维掺量、硅灰掺量下水泥石的抗压与抗折强度,得出各水灰比下的强度最佳配合比,并测试最佳配合比下浆液的流动性与抗冲刷特性。试验发现,纤维与硅灰的掺入能够显著提高水泥石的强度,且对浆液的流动度影响不大;低流速下纤维硅灰水泥浆的抗冲刷特性较纯水泥浆改善显著,但流速较高时其抗冲刷特性仍较差。基于此,在纤维硅灰水泥浆中再掺入可再分散性乳胶粉进一步改善浆液抗冲刷特性。试验结果表明,可再分散性乳胶粉能明显改善浆液抗冲刷特性,即使在较高流速(0.6 m/s)下,其浆液留存率仍达到60%以上。研究结果为隧道突水灾害防治与动水注浆浆液选择提供了参考。  相似文献   

9.
钢渣是炼钢过程中产生的废渣,其产量约为粗钢产量的12%~20%(张海霞等,2011),截止2011年我国钢渣排放量约1.1亿t。钢渣尾渣的化学组成与水泥熟料相似,含有硅酸二钙(C2S)和硅酸三钙(C3S)等水硬性矿物,是一种具有潜在活性的胶凝材料(舒型武,2007),但钢渣的生成  相似文献   

10.
海底隧道注浆材料强度劣化规律及使用寿命研究   总被引:1,自引:1,他引:0       下载免费PDF全文
制备了水灰比分别为0.8、1和1.2的纯水泥浆液结石体试块,水灰比为1、粉煤灰掺量10%或20%的水泥-粉煤灰浆液结石体试块,矿粉掺量15%或30%的水泥-矿粉浆液结石体试块,硅粉掺量10%或20%的水泥-硅灰浆液结石体试块。将注浆浆液结石体试块浸泡在海水侵蚀环境中,试块无侧限抗压强度的变化规律。采用灰色关联理论研究了海水浓度、水灰比、矿物掺合料等因素对浆液结石体抗压强度的影响。通过建立多元灰色预测模型分析了海水侵蚀环境下水泥基注浆材料的强度劣化规律及使用寿命。结果表明:强度影响因素的灰色关联度由大到小的排序为:水灰比,海水浓度,测试龄期,硅粉掺量,粉煤灰掺量,矿粉掺量。  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

14.
15.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

16.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

17.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

18.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

19.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

20.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

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