基于ANSYS Workbench的混凝土冷却水管优化

为研究大体积混凝土冷却水管的间距及管径对降温效果的影响,利用ANSYS Workbench分析软件对埋设冷却水管的混凝土浇筑块模型进行温度场与温度应力场的仿真计算,并对埋设方案中的管间距、管径进行目标驱动优化分析,得出工程设计允许范围内的优化方案.     

小溪滩船闸大体积混凝土水化热分析

船闸闸室底板属于大体积混凝土构件,对大体积混凝土耐久性影响最大的是裂缝的产生,而裂缝的产生又与温度有关.文章利用有限元分析软件(Midas Finite Element Analysis)模拟小溪滩船闸底板水化热分析,计算大体积混凝土温度场发展情况,并将模拟计算结果与实测温度进行比较.结果表明,闸室底板中心点最高温度的计算值和监测值最大偏差为1.2℃,差异性较小,而最高点温度模拟结果与监测值的误差只有2%,中心点的降温速率为1.2℃·d~(-1),模拟得到的温度场与实测的温度变化规律较为吻合,为后续冷却水管的调整方案提供了有价值的参考.     

大体积混凝土配合比优化设计及施工工艺研究

对甬江特大桥承台大体积混凝土配合比及施工工艺进行了研究,为克服大体积混凝土因水化热产生开裂,工程采用控制水泥用量、掺加粉煤灰和矿渣及高效减水剂、延长混凝土设计龄期等方法,运用密实骨架堆积理论对混凝土配合比进行优化设计,通过预埋冷却水管降温措施及严格的施工管理,有效减小混凝土温度差,减少混凝土温度裂缝的产生.     

大体积混凝土基础的水管冷却温度场研究

针对大体积混凝土基础,进行混凝土浇筑后的温度场有限元分析,研究分析了冷却水管水平间距、竖向间距、入模温度与冷却水入管温度之差、水管长度、冷却水流量、混凝土基础厚度等参数对混凝土最高温度的影响.通过数值计算结果的回归,建立了大体积混凝土基础最高温度的实用估算公式,该公式与相关实测数据及分析结果相吻合,对大体积混凝土基础施工具有参考价值.研究结果表明,冷却水管的间距及水管长度对混凝土基础最高温度的影响最大.     

冷却水管在泄洪闸闸墩施工期温控中的应用

施工期通冷却水可降低大体积混凝土早期水化热,是成熟的冷却方法,闸墩结构中应用较少.本文结合白沙水库溢洪道闸墩结构中的冷却水管降温方案的设计,通过对水管冷却的热工计算,分析冷却水管冷却的降温幅度,对比相同施工环境条件下是否采用冷却水管的实际温度变化过程,表明水管冷却在泄洪闸闸墩施工期温度控制中使用可有效降低混凝土温度峰值,对闸墩结构的防裂具有重要意义.     

异形承台大体积混凝土水化热控制模型及跟踪监测

针对某异形承台大体积混凝土的水化热控制问题,提出了大体积混凝土的控制方法、并对其进行了实时跟踪监测分析与研究.其研究成果:承台混凝土浇注每层测点温度曲线规律呈现出一定的一致性:混凝土温度在浇筑后经历一个升温期后在冷却水管的作用下开始降温;承台混凝土浇注每层内表温差的变化都基本一致,而且随着气温的变化而上下起伏,且幅度比较大.     

相变储能大体积混凝土的控温性能

提出相变控温储能材料机敏控制混凝土结构温度裂缝技术途径.在混凝土浇注过程中将相变材料掺入使之与混凝土结构一体化,利用相变材料在特定温度范围的热效应控制混凝土内部温度场,从而机敏控制温度应力防止温度裂缝.通过自行设计的温度测试系统,对相变控温混凝土控温性能进行实测研究,结果表明:相变材料不但可以降低大体积混凝土的最高绝热温升值,而且可以降低大体积混凝土升温速度和降温速度,从根本上防止了大体积混凝土温度裂缝的出现.     

洛阳龙门高铁站大体积筏形基础混凝土温控措施分析与评价

为研究大体积筏板基础混凝土水化热过程,防止因温差过大而产生温度裂缝,以洛阳龙门综合交通枢纽大体积筏板基础混凝土结构工程为背景,运用有限元软件Midas FEA建立模型分析了筏板基础内部温度沿基础厚度方向和水平方向的变化规律,对比了有无管冷系统作用下筏板基础水化热温度场分布情况。研究结果表明：筏板基础外表面产生裂缝可能性较大,应采取相应保护措施;管冷系统降温效果明显,对比有无管冷系统作用两种情况,发现在管冷系统作用下,基础内外温差为22.8℃,最大温差降低6.3℃,现场实测最大内外温差为24.1℃,单日最大降温速率为1.3℃,两者全部达到规范要求,养护完成后筏板基础外部未存在明显裂缝,证明通过布设管冷系统,能够有效降低水化热作用的影响,缩小内外温差防止产生温度裂缝,保证了筏板基础的整体性和稳定性。     

大体积混凝土冷却管的设计

本文分析总结了承台大体积混凝土的施工,重点从温升计算、增设冷却水管等降温控制措施加以描述,总结出大体积混凝土冷却管的设计与施工的要点及关键。     

大体积混凝土冷却水管优化研究

冷却水管能够有效的降低大体积混凝土温度应力,其中冷却水管的各项参数起着决定性作用.利用三维有限元计算分析浇筑过程中坝段的温度变化,主要考虑了冷却水管与混凝土之间的热量交换、冷却水管沿程温度的逐渐变化,通过选择不同参数的冷却水管,对混凝土内部温度变化进行详细的计算分析.结果表明:冷却水管的排布型式、通水温度、时间,对混凝土温度有着显著的影响,合理选择各项参数能够有效降低混凝土内部温度梯度,减小温度应力从而预防温度裂缝的产生,对大体积混凝土的温控防裂有着积极的意义.     

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.