高流速卵石地层地铁联络通道人工冻结温度场研究

地铁联络通道的开挖经常受到地下水干扰,人工地层冻结法凭借其优秀的封水性和适应性成为富水地层联络通道施工的首选工法。依托北京地铁12号线苏州桥站~人民大学站区间1#联络通道冻结工程,通过现场实测研究地层温度场和泄压孔压力的发展规律,分析冻结帷幕的交圈特征,确定高流速地层冻结壁薄弱位置。结果表明：盐水去回路温度在冻结初期迅速下降,而后降速减缓并最终稳定在-28℃以下;测温孔中土体与管片交界处的温度高于土体内部,渗流上游冻结壁温度高于下游,这些区域应当重点监测;冻结至59d时,利用基于实际降温速率的分阶段冻结壁厚度计算方法求得不同截面位置处的冻结壁最小厚度为2 495.2mm,同时泄压孔压力已全部释放并保持稳定,冻结壁不再发展,满足联络通道开挖要求。研究成果能为高流速地层的人工冻结参数选取和监测提供理论支持。     

严寒地区地铁联络通道冻结法施工监测分析

基于哈尔滨地铁某站的联络通道冻结施工法,对土体温度场进行研究,介绍运用冻结法进行土体加固时温度场的变化规律.运用冻结法对联络隧道四周土体加固时,盐水降温初期土体的温度下降较快,由于土体中水分的潜热影响,0℃附近降温过程会经历一个平台期,温度降至0℃以下,土体温度继续下降,相对于盐水降温初期降温速率变慢.计算出冻结过程中的所需冷量,可为今后类似工程提供参考.     

基于随机介质理论的盾构穿越富水砂卵石地层扰动分析

在富水砂卵石地层进行隧道开挖会诱发地层损失、引起周围建筑变形失稳等问题,为了对富水砂卵石地层中隧道开挖引起的地层扰动进行分析,基于传统随机介质理论推导了地表竖向位移、水平位移、倾斜曲线、横向变形及曲率的计算公式,并以万家丽电力隧道为依托,计算得到了反映地层扰动的位移曲线.研究表明盾构开挖后隧道地表沉降量呈现单峰状态、水...     

砂卵石地层盾构隧道掌子面稳定性理论分析

盾构隧道穿越砂卵石地层掘进施工时,由于砂卵石的地层特性及施工扰动,隧道掌子面容易失稳而引发事故。为研究砂卵石地层盾构隧道掌子面稳定所需的最小支护力,结合砂卵石地层的掌子面失稳模式,在三维Murayama模型的基础上,将掌子面前方土体的滑动面形式假设为对数螺旋滑移线,结合上部松动区域的破坏机制,引入椭球体放矿理论,对传统的棱柱体筒仓模型进行改进,进一步通过极限平衡法推导出砂卵石地层的掌子面极限支护力求解公式;最后通过离散元数值模拟验证所推公式,两者的误差为3.1%。结果表明所得公式可对砂卵石地层的掌子面极限支护力进行较为精确的求解。研究成果以期为砂卵石地层掌子面极限支护力计算理论提供依据。     

穿越不同地层位置的隧道围岩稳定性研究

为研究隧道穿越不同地层位置时围岩的稳定性,以青海东部隧道的施工为案例,采用三维有限元数值计算方法模拟了隧道在穿越黄土层、黄土层和卵石层夹层、卵石层时围岩的稳定性变化规律,通过3种情况下应力场和位移场的对比发现,隧道穿越砂卵石地层时的变形及应力远远大于穿越黄土层,且在隧道穿越卵石层时拱顶出现拉应力;隧道拱底隆起大于拱顶沉降,特别是隧道穿越黄土层拱底隆起远远大于拱顶沉降.因此,隧道应尽量避免穿越砂卵地层;穿越卵石层和黄土层的隧道也要采取相应措施,避免围岩被破坏.     

水泥预加固-人工冻结联合工法加固地层冻胀特性

为研究采用联合工法施工,能够有效控制土体冻胀位移的施工参数,本文以广州地铁十四号线某联络通道冻结工程为背景,通过有限元软件建立联络通道冻胀位移场三维数值模型,研究了盐水温度和水泥掺量对土体冻胀位移的影响,并计算不同冻结壁厚度下地表冻胀位移量以及联络通道开挖土体的塑性区域,在满足施工安全的前提下,进一步对冻结壁设计参数进行优化,以减小土体冻胀位移。结果表明：采用水泥预加固-人工冻结联合工法施工,当水泥掺量设定为12%,盐水温度控制在-25℃~-31 ℃时,积极冻结末期,地表冻胀位移能够满足工程监测要求;水泥掺量设定为12%,冻结壁厚度设定在1.8m,盐水温度控制在-31 ℃。可见相对于原施工方案,采用联合工法施工,积极冻结末期地表冻胀量减小了73%。     

砂卵石地层浅埋地铁锚杆竖向预加固理论及技术研究

盾构法在隧道施工中的应用越来越普遍,其施工过程不可避免地会引起地层的移动和变形。目前,对砂卵石地层中盾构施工地层变形规律和控制方法研究较少,缺乏可供参考的研究成果。依托砂卵石地层盾构施工现场工程,采用模型计算的手段,探讨了用地表砂浆锚杆对盾构施工隧道地表进行预加固的机理与效果。结果表明,此工程技术可有效提高砂卵石地层开挖段的土体抗剪强度,抑制上部松散地层的下沉滑移;得出浅埋地层锚杆加固深度合理范围,并总结出开挖土体内摩擦角和粘聚力的提高能有效减小开挖面应力的基本规律,从而为今后盾构隧道开挖面稳定性分析提供了新的思路和方法。     

砂卵石富水区域盾构小净距穿越单洞双线暗挖站施工技术

为研究砂卵石富水区域盾构小净距穿越单洞双线暗挖站施工对既有暗挖站的影响,文章以小净距既有暗挖站段新建盾构区间隧道工程为背景,对盾构区间隧道工程施工进行设计,并用MIDAS计算分析程序对砂卵石富水区域盾构小净距穿越单洞双线暗挖站施工过程进行数值计算分析;总结了盾构小净距穿越施工过程中既有暗挖站位移变化规律;研究了既有暗挖站明暗挖分界位置变形缝差异沉降特征;分析了既有暗挖站轨道沉降变化走势;监测结果与仿真结果变化规律基本一致,佐证了仿真计算的可靠性。     

砂卵石地层地铁近接下穿既有盾构区间施工控制技术

为探究地铁暗挖近接施工下穿既有盾构区间加固技术适应性,以成都5号线近接下穿既有3号线为工程背景,提出适应于成都砂卵石地层的预埋注浆加固保护方案,且通过数值模拟研究了不同注浆加固范围的保护效果、注浆过程对隧道结构影响以及对下穿过程规律性进行讨论,并结合现场监测分析.结果表明:既有隧道注浆加固范围扩大,其隧道结构变形呈线性减小,隧道结构纵向沉降槽呈线性缩小,适当增大既有隧道注浆范围可控制其变形量;预埋钢花管注浆加固过程中,浆液压力和土体硬化将导致既有隧道结构竖向产生沉降,水平方向相向靠拢;地铁下穿过程中,既有隧道结构主要产生竖向沉降,先缓慢沉降,隧道穿过后沉降变形突增,再趋于稳定,前期有一定反应阶段;相比既有隧道,近距离的大范围注浆加固导致土体硬化,5号线结构变形预变形阶段极大缩短,反应时间短,施工风险增大.提出二次衬砌工序优化、深孔注浆加固补救措施以及节点位置格栅密排等措施能够降低既有盾构运营风险.     

分离岛式地铁车站交叉洞群施工的周边环境效应分析

为研究分离岛式车站交叉洞群的周边环境效应,以广州市某暗挖地铁车站为工程背景,采用数值模拟的分析方法,建立了正线隧道、联络通道和站台横通道的多洞室数值计算模型,同时考虑左右线隧道穿越不同岩性的地层,有限元模型地层为不均匀地层。通过数值模拟研究了隧道交叉洞群施工引起的地表沉降、围岩应力应变特征、支护变形受荷规律等,并将模拟结果与相应的现场监测数据对比分析。计算结果表明：中洞施工会引起围岩应力场位移场重分布,上覆围岩会向两侧滑动,造成洞间土体呈受压状态,侧洞会向两侧位移;支护结构最大应力值出现在隧道与联络通道的接口处,并且隧道支护结构应力值大小与距交叉段远近成负相关,离交叉段越远,支护应力值越小。研究成果为今后类似工程条件下城市地铁隧道施工提供参考。     

Markedness and its Interpretation in Language Use

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

Features of Women's language

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

A computer generator for randomly layered structures

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

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.