竖向荷载作用下无粘结预应力砼平板-T形柱节点的试验研究

进行了6个足尺平板-T形柱节点试件的冲切性能试验．阐述了平板-T形柱节点的冲切受力性能和破坏特征，分析了无粘结预应力钢筋的应力变化特点以及板暗梁面筋和抗冲切箍筋的应变发展特点，对比了试件的极限承载力．试验结果表明，施加一定预压应力的试件具有较好的抗冲切受力性能，增加预压应力和平板厚度可提高节点的冲切承载力．     

后张无粘结PC平板-T形柱节点的试验研究

进行了6个足尺PC（预应力混凝土）平板-T形柱节点试件在竖直荷载作用下的冲切性能试验．其中，5个试件的平板中配有无粘结预应力筋，1个对比试件的平板中配普通钢筋．通过试验阐述了节点试件的破坏特征．结果表明：所有试件都产生弯曲冲切复合破坏特征；当接近极限荷载时，预应力筋的应力有较大幅度的增加，但未达到其极限强度；在保持一定的延性的条件下，平板中的预压应力可提高节点的冲切承载力和刚度．文中还根据试验结果给出了临界截面的形状和节点弯曲破坏的位置，最后采用美国ACI规范和我国规范所推荐的计算公式对上述节点的冲切承载力进行了验算．     

钢筋混凝土十字形柱-板柱连接冲切性能试验研究

进行了6个十字形柱-板柱连接(其中3个未配置、3个配置了抗冲切锚栓或箍筋)和2个对比方柱-板柱连接的冲切试验,研究了异形柱-板柱连接的冲切受力特性,同时将锚栓和箍筋的抗冲切性能进行了对比.试验结果表明,与方柱-板柱连接试件相比,在柱截面积相同的情况下,异形柱-板柱连接试件具有较高的抗冲切承载力.抗冲切钢筋可以有效地提高板的冲切承载力和延性.在改善延性方面,锚栓比箍筋更有效.另外,将国外几个主要规范ACI318、BS8110及MC90关于非矩形荷载面冲切临界截面周长的规定进行了比较,从试验结果看,规范ACI318的取法更合理.     

钢管混凝土板柱结构剪力环节点冲切试验

介绍了钢筋混凝土板柱结构节点的试验结果,受力性能和变形性能,探讨了剪力环尺寸和刚度,预应力混凝土及主筋是否穿过核心区对冲切性能的影响,同时给出了受冲切承载力的计算模式。     

钢筋混凝土十字形异形柱-板柱连接抗弯承载力的研究

为了研究柱截面形式为异形柱的板柱连接冲切受力性能,进行了柱截面形状分别为3种典型异形柱(十字形、T形和L形)和对比方柱所构成的板柱连接的冲切特性试验.根据所进行的柱截面为十字形异形柱-板柱连接冲切特性的试验成果,提出了十字形柱-板柱连接的屈服线形式,并应用屈服线理论,导出了十字形异形柱-板柱连接的抗弯承载力表达式.该式形式简单、应用方便,其理论计算值与试验值比较,符合较好.结果可供类似柱形的板柱连接强度计算时参考.     

新型钢管混凝土板柱结构中柱节点抗震性能试验研究

对5个新型钢管混凝土板柱结构中柱节点的模型试件进行了低周反复荷载作用下的试验研究,分析并评价了不同配筋方式对其破坏形态、滞回特征及延性等抗震性能的影响.试验结果表明：新型钢管混凝土板柱节点在低周反复荷载作用下具有良好的受力性能,其构造方式能够满足＂强柱弱板＂的抗震设计原则;在柱上板带配置抗冲切箍筋能有效提高节点的抗震性能;无论是否配有抗冲切箍筋,弯曲破坏时节点的塑性变形能力和抗震性能均优于发生冲切破坏的节点.     

空心板柱结构中柱节点受冲切承载力试验研究

为了研究板厚、肋宽、配筋率对空心板冲切性能的影响,对9个空心板柱节点试件进行了抗冲切试验,得到不同条件下空心板柱结构节点的开裂荷载、极限荷载、板底位移以及钢筋和混凝土的应变数据.采用数据对比和理论分析的方法,研究不同板厚、孔径、肋宽和配筋率对冲切承载力的影响.试验结果表明:空心板柱结构节点的冲切破坏形式为脆性破坏;初始裂缝发生在顺管向加载柱板底外边缘和板底边之间;顺管向和垂直管向的冲切角度分别为50°～60°和30°～45°,即顺管向的冲切角大于垂直管向的冲切角;增大肋宽、板厚和板底配筋率可以提高节点的抗冲切承载力.     

竖向荷载和不平衡弯矩共同作用下板柱节点的设计

在试验研究和理论分析的基础上,给出了普通板柱节点和配置抗冲切钢筋板柱节点的受冲切承载力计算公式,同时给出了板柱节点在竖向荷载和不平衡弯矩共同作用下等效竖向荷载设计值的计算方法,简化了复杂受力条件下板柱节点的设计．试验研究表明,抗冲切锚栓是有效的抗冲切钢筋类型,不但能提高板柱节点的受冲切承载力,而且能改善板柱节点的延性．抗冲切锚栓的布置方式包括正交布置和径向布置,且抗冲切锚栓应在柱周边区域均匀分布．本文给出了板柱节点抗冲切的设计步骤和方法,并给出抗冲切锚栓的设计方法和构造措施．同时给出了板柱节点配置抗冲切锚栓的算例,验证了抗冲切锚栓的设计方法,可用于板柱节点的工程实践．     

竖向荷载下空心楼盖板柱节点试验研究与计算分析

为了研究抗冲切元件和板厚对空心楼盖板柱节点受力性能的影响,在柱周围楼盖局部实心和布置暗梁的前提下,对6个节点试件进行竖向荷载作用下的试验研究与计算分析.对比研究了6个试件的破坏机制、承载能力、变形能力和应变分布,基于屈服线理论提出了节点的极限承载力计算方法.结果表明,空心楼盖板柱节点具有冲切破坏和弯曲破坏的双重破坏特征,并以弯曲破坏为主.增加板厚和配置抗冲切元件均可提高节点的极限承载力和刚度.与增加板厚和弯起钢筋相比,配置型钢剪力架对节点极限承载力的提高效果更为明显.节点设计时,可优先选择配置型钢剪力架参与节点抗剪.节点的极限承载力计算方法综合考虑了抗冲切元件、楼板配筋率和空心率的影响,计算值与试验值吻合较好.     

无粘结PC平板-T形柱节点的反复加载试验

在6个无粘结预应力砼(PC)平板-T形柱节点试件的低周反复加载试验基础上．描述了各试件的受力过程和破坏特性,分析对比了T形柱截面参数和不平衡弯矩加载方向对该节点刚度、承栽能力退化和耗能能力、变形恢复能力的影响,并对该节点的抗震性能进行了评价．研究结果表明,该节点具有较好的抗震性能,T形柱腹板长度c1对节点的抗震性能具有决定作用．     

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).     

An Index mechanism for multi-scale view in spatial databases

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.     

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.