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1.
采用矿渣、钢渣、脱硫石膏和普通硅酸盐水泥联合制备固化剂,对黄河冲积粉土进行改良固化,在提高工业废渣资源化利用的同时,以期解决黄河冲积粉土强度低、水稳性差等路基工程应用难题。首先,基于无侧限抗压强度试验、水稳性试验和干湿循环强度试验探究固化剂掺量和养护龄期对固化粉土强度的影响规律,确定固化剂的最优掺量;其次,针对最优固化剂掺量的固化粉土,开展不同龄期固化粉土的渗透性试验,同时结合核磁共振测试、矿物成分分析以及电镜扫描,揭示固化粉土的矿物成分及微观结构的演化规律。研究结果表明:矿渣-钢渣-脱硫石膏-水泥固化粉土的最优掺量为干燥粉土质量的10%;固化粉土的水化产物主要为水化硅酸钙凝胶(C-S-H)和钙矾石晶体(AFt);水化产物的粒间胶结和填充作用使土颗粒间形成致密结构,增强了固化粉土的力学强度、水稳性和抗渗性能。  相似文献   

2.
淤泥质软土通常难以满足路基工程填料要求.为利用淤泥质土和工业固体废弃物,采用流化床燃煤固硫灰固化淤泥质软土,通过标准击实试验、强度试验、水稳性试验,结果表明:掺加固硫灰使击实淤泥质土最佳含水量提高,最大干密度降低;固硫灰固化淤泥质土能提高淤泥质土的强度,符合路基填土要求;固硫灰最佳掺量为20%较合适,继续增大固硫灰掺量,所产生的强度增加幅度不明显,同时,在固硫灰中掺加适量石灰,强度可大幅提高;固硫灰能显著改善淤泥质土的水稳定性,这与固硫灰形成水硬性胶凝材料有关;固硫灰固化淤泥质土的微观形貌表明存在明显的火山灰反应.  相似文献   

3.
为了使废弃的淤泥获得工程价值,提高淤泥土的强度,通过对不同掺量的水泥和离子固化剂的配比,研究固化后淤泥在不同龄期下无侧限抗压强度,分析了水泥掺量和离子固化剂掺量对固化土抗压强度的影响,确定了离子固化剂的最佳掺量,得出了淤泥离子固化土的两种破坏形态。结果表明:淤泥固化土的抗压强度与水泥掺量成明显的线性递增关系,当离子固化剂的掺量达到0.02%时抗压强度不再明显的增加,甚至会降低;离子固化剂固化淤泥土有利于提高早期强度;当6%水泥和0.02%离子固化剂掺量时可达到工程要求,可见淤泥离子固化土的研究具有重要的工程意义。  相似文献   

4.
为了实现疏浚淤泥的快速处治,以河道疏浚底泥为研究对象,采用先排水后固化的处理思路,首先在淤泥中添加絮凝剂,含水率迅速降低,在絮凝剂脱水的基础上,再加入固化剂,对固化土进行含水率、液塑限、无侧限抗压强度以及微观特性进行试验研究。结果表明:在絮凝脱水淤泥中加入水泥后含水率降低,固化龄期越长、水泥掺量越高,含水率越低;随着固化剂掺量的增加,固化土的液限逐渐降低,塑限逐渐增大,塑性指数减小,且10%水泥掺量下的淤泥固化土强度可达到136. 5 kPa和143. 4 kPa;絮凝剂对脱水的促进效果远大于其在固化时的负面效果。  相似文献   

5.
周大禹  陈龙  王福喜  谢珂 《河南科学》2019,37(5):754-761
针对就地固化土路基,将废弃的淤泥土就地固化后用作路基填料,达到了废弃资源的合理利用,对实际工程具有重要意义.通过室内试验对就地固化土的压实特性和路用力学参数进行研究,发现水泥和矿渣微粉可以有效改良河道淤泥土,其中11%的固化剂总配比,满足规范中对上路床的强度要求;使用室内承载板法发现,11%固化剂掺量能够满足沥青路面对土基回弹模量的要求;随着固化剂总配比的增加,试样的CBR值基本呈线性增加,可以用一次多项式较好的拟合;随着击实前闷料时间的增长,击实后固化土的强度增大.  相似文献   

6.
文章基于路基的力学及路用性能,进行高性能固化剂和其他材料稳定粉质土路基的室内及现场试验的对比研究,以确定稳定粉质土路基的合理方案及固化剂掺量.室内试验结果表明,掺加高性能固化剂可明显增加粉质土的无侧限抗压强度和水稳性,减小其收缩变形;现场试验结果表明,掺加4%高性能固化剂的粉质土路基早期强度较高、变形较小、整体刚度好,能满足路基的各项技术指标要求.  相似文献   

7.
以上海高含水率的淤泥质粉质黏土为研究对象,通过试验方法分析不同固化剂的固化性能。试验中采用石灰、石膏、矿渣微粉、超细水泥等部分替代水泥以组成不同配比的固化剂,以固化软土的UCS为主要指标,研究不同配比固化剂对高含水率软土早期固化效果和破坏特点。研究结果表明:(1)当高含水率软土中固化剂总掺入比为20%时,超细水泥对固化土的抗压强度性能影响最大;(2)随着超细水泥掺量的增加,固化软土抗压强度逐渐增大,但对于含水率50%的固化土由于二次水化反应的不充分抗压强度增长缓慢,超细水泥掺量存在一定的阈值。  相似文献   

8.
采用水玻璃作为碱激发剂激发粉煤灰和矿粉的活性来固化疏浚淤泥,对固化淤泥进行无侧限抗压强度试验、扫描电镜(SEM)以及X射线衍射(XRD)测试,研究了固化材料配比、龄期、水玻璃掺量及水玻璃模数对固化疏浚淤泥强度的影响,确定了各组分之间的最佳配比,观测了固化淤泥的物相组成及显微结构特征.力学试验结果表明:水玻璃掺量7%、模数1.0~1.5时对粉煤灰和矿粉的激发效果最优,相比于粉煤灰,水玻璃对矿粉的激发效果更佳;水玻璃模数相同的情况下,矿粉掺量越大强度越高;各组分最优配比(疏浚淤泥、矿粉、水玻璃质量比为60∶40∶7)时,28d无侧限抗压强度可达到12 140kPa.SEM和XRD试验结果显示:在水玻璃的激发下,固化淤泥水化生成长石类和沸石类等晶相,这些晶相连接紧密,形成致密的微观结构,这是固化后疏浚淤泥强度的最重要来源.  相似文献   

9.
为探讨固化剂对某地海相土的固化效果,制备了固化剂掺量10%~14%,压实度94%~98%的固化土试样,经标准养护后,分别进行了7~180 d养护时间的无侧限抗压强度试验.试验结果表明:尽管固化土的无侧限抗压强度都分别随压实度和固化剂掺量的增大而增大,但对掺量为10%和12%的固化土来说,提高压实度,其强度增加则更为明显,而对于压实度为98%的固化土来说,增加掺量并不能有效增加其28 d之前的强度.另外,固化土的无侧限抗压强度随时间增长而增大,但超过90 d后已趋于稳定.  相似文献   

10.
为探究石膏碱激发粉煤灰地聚物固化黄土的力学性能及其机理,确定最佳组分比,进行无侧限抗压强度试验、X射线衍射(XRD)及扫描电子显微镜(SEM)分析.结果表明,固化黄土的强度随石膏掺量的增加而增大;石膏掺量质量分数为1.5%,熟石灰∶粉煤灰(质量比)=7∶14时,强度最大;XRD分析结果表明石膏碱激发地聚产物主要为水化硅酸钙和钙矾石,起到胶结土颗粒以及填充的作用; SEM分析进一步证明固化土体微观结构的完整性和连续性由于地聚物的生成得到提升,印证了强度规律及固化原理,为实际工程应用提供了参考.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

13.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

14.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

18.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

19.
20.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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