Geopolymer concrete-filled pultruded composite beams – Concrete mix design and application

The limited research on the geopolymer concrete mix design for targeting a specific strength is identified an obstacle for their effective design and wide use. In this paper, a mix design procedure has been proposed for fly-ash based geopolymer concrete and its use as infill hybrid composite beam is investigated. Then, the structural performance of geopolymer concrete filled hybrid composite beam is investigated to determine their possible application in civil infrastructure. Firstly, a detailed procedure of mix design for fly-ash based geopolymer concrete is presented. Secondly, three hybrid beams filled with geopolymer concrete were prepared and tested in a four-point bending setup to evaluate their flexural modulus and modulus of rupture. Numerical and analytical evaluation of the behaviour of hybrid beam were performed and results showed a good agreement with the experimental investigation. Thirdly, the suitability of the beam for a composite railway sleeper is evaluated and compared with existing timber and composite sleepers. Finally, the beams’ performance in a ballast railway track is analysed using Strand7 finite element simulation software and the results showed that the new concept of using geopolymer concrete as infill to pultruded composite section satisfied the stiffness and strength requirements for a railway sleeper.     

新疆油区蒸汽吞吐加密井开发技术经济指标

针对新疆油区稠油开发现状,结合经济评价方法,确立了稠油油藏蒸汽吞吐加密开发经济极限单井控制可采储量、极限有效厚度、油汽比等一系列技术经济指标,制定了稠油油藏加密筛选标准,建立了一套计算各经济极限指标的方法。对新疆油区稠油油藏的九个区块进行了计算,计算结果表明该方法是科学可行的。     

特低渗透油田裂缝发育区剩余油分布及调整技术

安塞油田为特低渗透油田,局部裂缝较发育,注水开发后部分油井含水上升快,而周围存在较大范围的低产低效井,降低了注水波及系数,影响油田开发效果。通过研究裂缝发育区水驱油特征并认识其剩余油分布规律,提出挖潜裂缝发育区（ 块） 剩余油的调整技术。现场应用结果表明,该技术能有效地改善油田开发效果。研究过程中,应用微观砂岩模型观察双重孔隙介质模型的水驱油方式,结合裂缝发育区典型井组动态反映、沿裂缝注水试验及检查井的结果,确定安塞油田裂缝发育区水驱油方式主要为裂缝部分基质孔隙驱油,其结果是剩余油大量分布在裂缝侧向,并且主要受油层物性、裂缝发育程度及井网部署方式的控制。提出与裂缝垂直距离约１２０ｍ 加密调整是安塞油田裂缝发育区目前有效的调整方向。图１ 表２ 参１（ 熊维亮摘）     

双河油田油层微构造特征对剩余油分布的影响

通过对双河油田主力油层微构造研究，总结出油层微构造特征及其主要类型，它包括正向微构造、负向微构造和斜面微构造等。生产实例表明正向微构造为剩余油富集区，负向微构造为严重水淹区。建议在制定油田开发加密调整方案时应充分考虑微构造因素，尽可能把加密生产井钻在正向微构造上，负向微构造只能钻注水井。     

浅薄层稠油油藏资源二次利用的一种方法—加密井蒸汽吞吐

由于河南油田稠油油藏具有“浅、薄、稠、散”的特点，所以蒸汽吞吐平均6个周期后，开发指标和经济指标明显降低。蒸汽吞吐后剩余油分布为：100m×141m及五点法并网，剩余油分布较为集中，100m×100m反七点法并网，剩余油分布零散；经济分析结果表明：浅薄层稠油油藏加密井吞吐单井的经济极限产量为1200～1500t，当油层厚度大于5.0m、纯总厚度比大于0.5，以及单井控制死油区面积大于0．5×10－2km2，且死油区离边水距离大于150m时，可进行加密，加密井蒸汽吞吐采收率可达14％左右。不同并网的加密方式为：100m×141m及五点法井网，采用直并加密方式；100m×100m反七点法并网，采用水平并加密方式。     

高含水后期加密调整井开发指标预测方法研究

通过对高含水后期加密调整井特点及其指标预测的特殊性研究，提出了随机模拟地质模型建模的原则 基础上，采用油藏数值模拟和预测放大方法较好地解决了加密调整井指标预测问题。     

A non-linear masonry infill macro-model to represent the global behaviour of buildings under cyclic loading

The presence of masonry infill walls in RC buildings is very common. However, and even today, in the design of new buildings and in the assessment of existing ones, these infill walls are usually considered as non-structural elements and their influence in the structural response is generally ignored. For horizontal loading, infill panels can drastically modify the response, attracting forces to parts of the structure that have not been designed to resist them. This paper presents an improved non-linear numerical simulation model for the influence of the masonry infill walls in the seismic behavior of structure. The model is implemented in the PORANL program. After the implementation and calibration of the proposed masonry model, a series of non-linear dynamic analyses of a building representative of Modern Architecture in Europe were carried out. The main objective was to investigate the behavior of this type of building, and any weakness under seismic loading. The building geometry and the dimensions of the RC elements and infill walls were set in the original project, and confirmed in the technical visits. The building under study has nine storeys and the structure is mainly composed of 12 plane frames oriented in the transversal direction. The building was analyzed with a simplified plane model, for each direction, and the existing infill panels were looked at in accordance with their dimensions and location. The earthquake action adopted in this study was simulated through three series of artificially generated earthquakes, for a medium/high seismic risk scenario in Europe.     

Kriging和距离因子辅助的全局优化方法

基于Kriging元模型的优化方法通常存在优化效率较低、收敛速度较慢、昂贵估值次数较多且难以有效平衡Kriging模型的局部与全局搜索行为等弊端。为此,提出一种序列Kriging和距离因子辅助的全局优化方法。其实现过程主要包含两个阶段:一是利用Kriging模型近似复杂昂贵的黑箱函数;二是利用Kriging模型与距离因子的乘积构造加点采样法则,并通过免于求导的DIRECT算法优化该法则,以获取新的昂贵估值点。六个数值函数测试和一个摆线泵仿真实例验证所提出方法的有效性。     

钢板剪力墙中墙-框架相互作用性能研究

在侧向荷载作用下,考虑填充板和框架杆件之间的相互作用,研究了钢板剪力墙双体系的非线性性能。对多组钢板剪力墙试件进行数值分析,研究填充板对框架性能的影响,评估其抵抗侧向力的有效度。结果表明:按规范设计的钢板剪力墙具有理想的屈服顺序,填充板首先进入塑性。这说明:填充板在加载初期非常有效,转角可达到1%,承担了大部分层间剪力。然而,一旦填充板中屈服区域继续发展,它们将逐渐失效;当屈服区域延伸至墙体,附加荷载将基本上由框架杆件承担。     

The effect of the infill in arched structures: Analytical and numerical modelling

Although arches, vaults and domes were essential structural elements in ancient engineering works, their structural analysis presents a challenge to modern designers. It was well known by the medieval builders that infill is essential for the stability of arched structures. Nevertheless, some disasters occur nowadays due to incorrect infill removal, usually done with the purpose of decreasing the applied load. In the present work a comprehensive analysis of the infill influence on the structural behaviour of arched structures is performed. For this purpose analytical models based on equilibrium considerations and finite elements models are used. Experimental results obtained from the Bargower bridge destructive test, are used to calibrate the numerical results. Some conclusions regarding the structural behaviour of arched structures and modelling strategies are presented.