公路沥青路面检测及养护的若干探讨

提高公路使用寿命,进行公路路面检测及养护已经成为公路养护部门刻不容缓的使命.分析当前公路沥青路面中出现的各种病害特征,着重介绍沥青路面弯沉检测技术、路面平整度检测技术、路面抗滑性检测技术、路面损坏状况检测技术的发展状况,探讨如何进行预防性公路养护的措施,客观而全面的论述如何开展公路路面维修治理工作,从而提高沥青公路的养护质量,方便车辆畅通无阻的运行.     

关于沥青路面结构设计的探讨

一、概述随着公路建设的发展,沥青路面已成为我国公路路面的一种重要型式。但是由于忽视了结构设计,在已建成的沥青路面中,沥青路面不同程度地出现早期破坏现象,路面达不到《公路柔性路面设计规范》     

沥青路面施工管理工作重点分析

沥青路面是我国公路建设中常用的路面结构形式,其施工质量对公路行车安全性、舒适性有着重要的影响.同时路面施工质量还会影响路面排水的情况,关系到降水是否渗透造成路基稳定性降低情况的发生.本文针对沥青路面施工质量的重要性,对沥青路面施工管理工作重点进行了分析与论述.     

公路沥青路面平整度问题解析和对策

公路沥青路面平整度问题是我国高等级公路建设普遍面临的问题之一。公路路面平整度是路面质量的重要控制指标,本文着重分析了影响公路沥青路面平整度的因素,并提出了提高沥青路面平整度的防范措施和对策。     

纤维微表处理论设计研究

1微表处发展现状 在我国公路的路面结构中,沥青路面占主要位置,特别是高等级公路达90%,但随着公路交通量的加大,轴重的增加、交通的渠化等,一般的沥青路面就出现了严重地早期破坏如车辙、开裂、坑槽等,从而使路面使用寿命大大缩短,为此我国公路研究人员一方面从沥青路面结构入手进行研究,     

高速公路沥青路面平整度问题的探讨

本文作者结合工程实践,指出了高速公路沥青路面平整度的影响因素和改善沥青路面平整度的施工措施。通过公路建设、养护的施工实践,探索分析了影响沥青混凝土路面平整度的因素,为公路沥青混凝土路面施工以及公路养护生产,保证路面平整度提供借鉴。     

重载作用下沥青路面结构验算方法

针对目前中国日趋严重的超载现象,为方便公路养护管理部门定期对路面结构状况进行调查评定,及时对相应路段公路进行维修养护,以现行沥青路面设计规范为基础,经过大量的数据分析对比,利用线性回归方法,获得了车辆重载运输轴载作用下的沥青路面标准轴载换算公式;同时根据沥青路面结构特点,对考虑重载作用的路面结构的验算内容和原则进行讨论和分析,最终确定以考虑超载作用的路面弯沉值、容许拉应力值、路面使用寿命及所需结构层厚度,作为沥青路面结构承载力验算的验算系统。研究结果表明:得出的沥青路面标准轴载换算公式以及沥青路面结构验算系统,对国道G108陕西渭南故市镇路段路面结构状况的调查评定是合理的,评定结果可为公路养护部门提供科学的决策依据。     

浅谈沥青公路路面过早破坏的成因

在中国经济强劲发展的带动下,公路建设也蓬勃发展起来。与此同时,公路建设中的一些问题也暴露出来。沥青路面是当前公路建设中使用较为普遍的面层铺装方式,新修公路的沥青路面过早的破坏,降低了公路的使用寿命,对新修公路的正常使用构成很大的威胁。下面通过沥青路面由于在路基施工、路面设计、路面施工、货车超载以及公路养护管理中存在的问题而导致的早期病害问题进行分析,并希望能够引起大家对这一问题的重视。     

北方地区路面裂缝病害成因及防治

在我国北方地区,路面主要以半刚性基层的沥青路面为主,但是路面裂缝现象屡见不鲜,这不仅破坏路面连续性和平整性,影响行车舒适性,而且容易造成水损害,降低公路使用寿命。因此,科学分析、预防和处治沥青路面裂缝,是提高公路服务水平和延长公路使用寿命的关键。     

公路沥青路面的病害成因与预防探讨

沥青混凝土路面因具有诸多优点，成为公路建设常用的一种材料。如造价低、工期短，嗓音小且舒适等原因而广泛应用于公路建设中。无论从乡村道路到城市道路，从低等级公路到高速公路，从路面底基层到路面面层，均普遍采用了这种设计。但是，沥青路面的病害却给交通带来诸多不便，本文将结合笔者在公路沥青路面设计的实际经验，分析了这种病害成因，并对沥青路面病害的预防进行了有益的探讨。     

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…     

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.     

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.