高海拔寒区隧道保温防冻系统设计要点分析

在对隧道保温防冻层作用、隧道冻害的主要特点以及隧道保温防冻设计中存在的主要问题进行论述的基础上,分析了防排水与保温防冻系统作用之间的关系,提出了防排水与防冻保温系统设计原则.从隧道保温防冻系统设计要素、保温防冻系统类型、保温防冻材料选用以及洞体保温防冻系统设计、排水管出水口保温设计等方面对高海拔寒区隧道保温防冻系统设计要点进行了系统性分析,并提出隧道保温防冻系统设计改进措施.     

硬质聚氨酯在寒冷地区隧道冻害防治中的应用

为了防治隧道的冻害,研究了硬质聚氨酯泡沫塑料的性能、加工工艺及施工安装方法,发现在施工现场修建临时生产厂房,采用手工注入成型工艺,适合现场工作条件,生产成本低,可大大节省工程造价。另外,选用966氯丁防冻胶作为粘结剂,将加工成1 000 mm×460 mm×40 mm的硬质聚氨酯泡沫塑料板材粘结在防水层上是切实可行的施工安装方法。同时,对现场加工的硬质聚氨酯泡沫塑料板材的技术指标进行了检测和验算。结果表明:其密度、压缩性能、吸水率和导热系数均符合标准要求,梯子岭隧道的最大围岩压力为71.1 kPa,远小于硬质聚氨酯板材压缩应力(202kPa),而且防冻隔温层是铺设在原衬砌表面,在原衬砌的作用下,隧道结构体系已稳定,故硬质聚氨酯的强度完全满足要求。     

寒区隧道衬砌电加热试验研究

寒区隧道冬季易出现衬砌破损甚至滴水结冰等冻害，为此，除了做保温层外，主动加热系统也是必要的，主动加热系统主要由二次衬砌和保温层间的电热带组成.为了模拟隧道衬砌混凝土表面滴漏水结冰后从负温加热至正温的工况，对负温条件下的混凝土试件进行电加热模型试验研究，包括对单独试件及三联试件进行加热试验.结果表明:在采用长度2m、功率30W、埋置深度10mm的电热带，并选用40mm厚的聚氨酯板作为保温层时，混凝土试件表面温度能够在60min之内从-4℃升高至0℃以上.研究成果可为寒区隧道融冰防冻提供指导.     

寒区隧道温度场计算模型与保温层设防数值分析研究

我国大量寒区隧道冻害问题严重,对隧道结构稳定性和行车安全性造成极大威胁.对严寒地区哈尔滨天恒山隧道保温层施工前后进行温度监测,建立了考虑相变的平面瞬态温度场计算模型,并利用ANSYS有限元进行数值分析研究.计算了保温材料在三种不同工况下的设置方式,完成了热-应力耦合作用下的隧道结构变形分析.结果表明,利用瞬态温度场原理建立的ANSYS模型具有较高的精度和可靠性;在防冻措施上采取分层设置保温层的做法效果明显;隧道结构应力受到温度变化影响较大,设置10 cm厚PU聚氨酯保温层后,能够避免混凝土衬砌层开裂,有效减少冻害现象的发生.     

寒区隧道中玻化微珠保温砂浆隔热结构体系研究

如何在隧道中采取行之有效的冻害防治措施,保证安全运营,是当前隧道工程界迫切需要解决的问题。笔者针对寒区隧道的冻害防治技术之一——保温隔热材料防冻措施,提出玻化微珠保温砂浆隔热结构体系,用玻化微珠保温砂浆隔热层代替原来的有机保温材料隔热层,通过保温砂浆试验研究与隔热层结构设计计算,进一步达到隧道保温防冻技术的要求。     

浅析塔里木垦区衬砌渠道冻害原因及其防治措施

通过分析研究，塔里木垦区衬砌渠道冻害主要有冻胀破坏和冰冻破坏。冻胀破坏是由士壤中的水、土体颗粒物理性质和负温所致，大多发生在渠道的中下部。冰冻破坏是由于渠道结冰后渠道衬砌材料受冰压力使渠道受到破坏变形。渠道防冻害处理可通过设计选线、改变渠道结构形式、改变渠基土体的基本结构、使用新型建筑材料及运行管理等方法来实现。对渠道防冻害处理方式的选择，关系到渠道的造价和施工的难易，在今后的渠道设计与运行管理中不断地总结经验，进一步完善衬砌渠道防冻理论和实际运用研究，总结衬砌渠道防冻害的有效措施，加以推广应用。     

基于事件树理论的既有隧道冻害等级划分体系

为了便于制定隧道冻害整治措施,采用事件树理论,以隧道冻害发生为初始故障事件,以隧道冻害发展、衬砌剥落掉块、路面溢水结冰、衬砌漏水结冰为后续事件,分析每个安全隐患的内在联系,估算每个安全隐患的整改费用和损失;将既有公路隧道冻害程度划分为5级,对寒区公路隧道冻害扩展演变设计了一个通用表格,建立了公路隧道冻害等级体系,并以某公路隧道为例对该体系进行了验证。结果表明:建立的公路隧道冻害等级体系能有效指导该隧道的冻害整治工作,避免了以往依靠经验判别冻害程度的随意性,提高了冻害整治措施制定的科学性和有效性。     

江西省1991—1992年枇杷冻害调查及防御技术探讨

对江西省１９９１年冬枇杷冻害的分布，冻害程度以及冻害对产量的影响进行了调查分析，提出了枇杷防冻，避冻的栽培措施。     

江西省1991─1992年枇杷冻害调查及防御技术探讨

对江西省１９９１年冬枇杷冻害的分布、冻害程度以及冻害对产量的影响进行了调查分析，提出了枇杷防冻、避冻的栽培措施。     

地质雷达在隧道健康诊断中的应用

为了诊断运营隧道病害的程度，评价隧道的安全状况，分析了造成隧道衬砌背部存在缺陷的原因。阐述了采用地质雷达对隧道衬砌质量进行无损检测的原理及方法，井对某公路隧道进行了健康诊断。地质雷达探测结果表明：隧道衬砌背后出现的空洞都是孤立的，拱顶和拱腰的空洞总长占隧道总长的9％，隧道除拱顶衬砌厚度有4％小于设计值外，其余各部位衬砌厚度均大于设计值。对地质雷达探测结果采用钻孔法进行验证，其结果相吻合。利用检测结果评价该隧道衬砌结构安全等级，结果为B级。     

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.     

A computer generator for randomly layered structures

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

海南岛地体及其毗邻陆缘晚中生代—新生代古地磁研究和构造演化

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。     

Exciton Seebeck in Molecular Systems

Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with     

Achieving Unusual States of Matter Under High Pressure

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     

《Chinese Science Bulletin》SUBJECT INDEX TO VOLUME 59(2014)

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An on-line scaling method for improving scalability of a database cluster

The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.     

An improved R-tree based on childnode''s probability

R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).     

Integrating GIS Web services based on mediating architecture

The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.     

Tracking data management using topology of moving object database system for moving object constrained trajectory in LBS application

Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.