氯氧镁水泥混凝土路面性能试验研究          下载免费PDF全文

常成功  肖学英  郑卫新  文静  董金美  安生霞 《盐湖研究》2016,24(3)

氯氧镁水泥混凝土是由轻烧氧化镁、氯化镁溶液和一些砂石反应生成的一种气硬性胶凝材料。利用镁水泥混凝土修筑示范路面,通过回弹仪、X-Ray 衍射仪(XRD)、扫描电子显微镜(SEM)检测路面的抗压强度、相组成和微观结构。结果表明：修筑示范路面早期抗压强度增加很快,三天就能通车,后期基本保持稳定。修筑路面的主要相组成为5.1.8相,不随路面使用时间的延长而变化且其具有针状结构。  相似文献   

绿色高性能减水剂与水泥相容性的评判方法与试验验证          下载免费PDF全文

郑捷  王帆  雷震东  陈景恒  郑山锁 《地震工程学报》2017,39(1):88-94

基于Matlab平台,同时考虑聚羧酸系高性能减水剂的饱和掺量点、水泥浆体的初始Marsh时间或流动度、经时损失率、凝结时间和泌水率的影响,将掺有聚羧酸系高性能减水剂受检水泥与基准水泥相比较的各因子作为评判其相容性的指标,建立相应的隶属度函数,运用模糊数学评判方法,打破基准水泥的局限,对聚羧酸系高性能减水剂与水泥的相容性作出较为全面和准确的综合性评价。试验结果分析表明,掺入评价结果为优的同一聚羧酸系高性能减水剂预拌混凝土性能与其水泥浆体一致,相关性较好。研究对于绿色高性能减水剂混凝土的配制具有指导意义。  相似文献   

用分段式霍普金森压杆对水泥石动态弹性模量和破碎吸收能的实验研究     

王强  王通  于长滨  王祥林 《地震工程与工程振动》2006,26(2):92-95

本文采用分段式霍普金森压杆(Sp litHopk inson Pressure Bar,缩写为SHPB),对各种配方水泥石材料的动态弹性模量、破碎吸收能进行了实验研究,并给出了部分实验结果。研究表明:采用SHPB技术测量水泥石材料的动态力学性能方法是可行的;填料增强是提高水泥石材料抗冲击性能的有效途径。  相似文献   

Late Holocene to Recent aragonite-cemented transgressive lag deposits in the Abu Dhabi lagoon and intertidal sabkha     

Yuzhu Ge  Chelsea L. Pederson  Stephen W. Lokier  Jan P. Traas  Gernot Nehrke  Rolf D. Neuser  Katja E. Goetschl  Adrian Immenhauser 《Sedimentology》2020,67(5):2426-2454

Modern cemented intervals (beachrock, firmgrounds to hardgrounds and concretionary layers) form in the lagoon and intertidal sabkha of Abu Dhabi. Seafloor lithification actively occurs in open, current-swept channels in low-lying areas between ooid shoals, in the intertidal zone of the middle lagoon, some centimetres beneath the inner lagoonal seafloor (i.e. within the sediment column) and at the sediment surface the intertidal sabkha. The concept of ‘concretionary sub-hardgrounds’, i.e. laminar cementation of sediments formed within the sediment column beneath the shallow redox boundary, is introduced and discussed. Based on calibrated radiocarbon ages, seafloor lithification commenced during the Middle to Late Holocene (ca 9000 cal yr bp ), and proceeds to the present-day. Lithification occurs in the context of the actualistic relative sea-level rise shifting the coastline landward across the extremely low-angle carbonate ramp. The cemented intervals are interpreted as parasequence boundaries in the sense of ‘marine flooding surfaces’, but in most cases the sedimentary cover overlying the transgressive surface has not yet been deposited. Aragonite, (micritic) calcite and, less commonly, gypsum cements lithify the firmground/hardground intervals. Cements are described and placed into context with their depositional and marine diagenetic environments and characterized by means of scanning electron microscope petrography, cathodoluminescence microscopy and Raman spectroscopy. The morphology of aragonitic cements changes from needle-shaped forms in lithified decapod burrows of the outer lagoon ooidal shoals to complex columnar, lath and platy crystals in the inner lagoon. Precipitation experiments provide first tentative evidence for the parameters that induce changes in aragonite cement morphology. Data shown here shed light on ancient, formerly aragonite-cemented seafloors, now altered to diagenetic calcites, but also document the complexity of highly dynamic near coastal depositional environments.  相似文献   

外加剂对低温水泥浆性能的影响试验研究          下载免费PDF全文

向浩天  蒋炳  李之军  陈礼仪 《探矿工程》2020,47(1):36-42

为解决在普通硅酸盐水泥（P.O42.5）或混凝土施工中遭遇低温环境而不能顺利凝固的问题。对普遍使用的硅酸盐水泥进行了基础性能测试试验,使用早强剂与高效减水剂对水泥进行调整性能,寻找出最佳的调整方案,对比调整前后水泥浆及水泥石强度等各项数据。结果表明10%早强剂、2‰JSS高效减水剂的调整方案较好地改善了水泥浆的流动性、凝结时间、水化热放热速率、结石率及水泥石的早期强度等问题。研究成果对低温条件下的混凝土施工有一定的参考价值。  相似文献   

海相软土场地水泥土劣化机理室内试验研究     

董猛荣  杨俊杰  王曼  刘强 《中国海洋大学学报(自然科学版)》2020,(1):93-103

将水泥土和周围土体作为研究对象,利用室内化学分析试验得到了离子浓度的时空分布规律,并从腐蚀离子干预水化反应进程和分解水化产物两个过程揭示了海相软土场地水泥土劣化机理。Ca^2+由水泥土向土体中扩散,Mg^2+、SO42^-及Cl^-从土体向水泥土扩散;随着水化反应的进行,Ca^2+不断生成,水泥土中足够多的Ca^2+是保证水化反应进行并维持水化产物稳定的必要条件,Ca^2+不断向土体扩散是水泥土劣化的原因之一;水泥土内部的SO42^-及Cl^-在浓度较低(分别低于9和15 g/L)时有利于水泥土强度的提高,浓度较高时则导致水泥土发生胀裂;水泥土中Mg^2+的存在会阻碍水化产物的生成并分解水化产物,但浓度较低(低于3 g/L)时,影响不明显;土体中Mg^2+、SO42^-及Cl^-浓度高于水泥土中的浓度,在水泥土表层与水化产物反应生成胶结性差及膨胀性高的物质,促使水泥土劣化。  相似文献   

Study of elastic-plastic damage model of cement consolidated soil with high organic content          下载免费PDF全文

CHEN Huie  WANG Qing  CAI Keyi 《世界地质(英文版)》2009,12(1):17-21

On the basis of elastic-plastic damage model of cement consolidated soil, the authors took organic contents into reasonable damage variable evolution equation in order to seek relation between the organic contents and parameters in the equation, and established the elastic-plastic damage model of cement consolidated soil considering organic contents. The results show that the parameters change correspondingly with difference of the organic contents. The higher the organic contents are, the less the valves of the parameters such as elastic modulus (E), material parameters (K, n) and damage evolution parameter (ε) become, but the larger strain damage threshold value (εd) of the sample is. Meanwhile, the calculation results obtained from established model are compared with the test data in the condition of common indoors test, which is testified with reliability.  相似文献   

水泥固化土新材料在围埝堤心结构中应用研究     

张敬  叶国良  朱耀庭 《海洋工程》2007,25(3):115-121

采用水泥固化土作为新的充填材料,对于缺少砂土的天津港地区,不仅可以减少砂料长途运输,节省能源,降低工程造价,而且可以充分利用港池和航道开挖的淤泥质粘土。根据室内成型试验、现场监测与检测结果探讨了水泥固化土新材料的工程特性等,为水泥固化土新材料在围埝堤心结构中应用打下了坚实的基础。  相似文献   

地方病高发区成井用胶质水泥浆的试验研究          下载免费PDF全文

冉德发叶成明  王建增郑继天 汪敏 《探矿工程》2007,34(3):1-4

通过地方病高发区成井用胶质水泥浆的试验研究，以普通水泥和膨润土为基本材料，同时添加改善材料性能的外加剂，研制了一种用于高砷、高氟、高矿化度地区水井成井的止水材料，具有流动性好、抗渗性高、不收缩、完全无毒、价格低廉等特点，特别是其高抗渗性和不收缩性非常适合地方病区成井时隔离劣质含水层，保证优质含水层与劣质含水层互不串通、不渗漏、不污染。  相似文献   

Mn content of reservoir calcite cement: A novel inorganic geotracer of secondary petroleum migration in the tectonically complex Junggar Basin (NW China)   总被引：1，自引：0，他引：1  

Cao Jian  Hu WenXuan  Yao SuPing  Zhang YiJie  Wang XuLong  Zhang YueQian  Tang Yong  Shi XinPu 《中国科学D辑(英文版)》2007,50(12):1796-1809

Electronic probe microanalysis(EPMA) results of reservoir calcite cement from fourteen core samples in the Junggar Basin show that Mn-content varies largely between different samples from below the detect limitation to 4.14%,while it displays a generally good correlation with oil-gas shows.This,therefore,likely indicates that concentration of the Mn-content of the calcite cement has a close rela-tion to the intensity of petroleum fluid charging during hydrocarbon secondary migration.In order to assess this hypothesis,oxygen and strontium isotopic measurements on sixteen calcite veins host in source sequences were carried out to investigate the feature of the oil-source petroleum fluid.Analytical results imply that during hydrocarbon generation and migration,deep hot fluid has dissolved volcanic minerals interlined between mudstone source rocks.As Mn is a kind of typical trace element enriched in volcanic rocks,it is reasonable to conclude that the petroleum fluid formed in the source sequences would be Mn-rich.Consequently,calcite cements precipitated from such Mn-rich petroleum fluid would be Mn-rich accordingly.Due to the geologic chromatographic effect during migration along reservoir rocks,the decreasing of the Mn-content of the reservoir calcite cements indicates the migration direction.Then,this novel geotracer was further successfully applied in the study of hydrocarbon migration in the Junggar Basin in combination with organic geochemical analyses during the hydrocarbon migration.The Mn content of the reservoir calcite cement appears promising as a novel inorganic geotracer for the petroleum migration.This paper represents a search for novel indicators of secondary petroleum migration in tectonically complex basins based on fundamentals of the reservoir fluid-rock interactions.  相似文献