ANSYS在环梁支护结构体系中的应用

结合弹性地基梁法和深基坑支护结构中的环梁支护结构体系的特点，提出了基于通用有限元程序ANSYS的空间分析模型。工程实例的计算结果表明，利用此三维模型进行环梁支护结构体系的计算分析是可行的，有一定的应用价值。     

热经济学在煤气厂的应用

提出了一种对用能系统进行热经济性决策的Yong经济系数法，利用热经济学对上海浦东煤气厂的能源利用进行了分析，计算出其Yong经济系数，利用Yong分析法指出其薄弱环节，据Yong经济系数评价其Yong损费与非能量遇的比例大小，得出此系统的热经济性。     

数值模拟联合算法及其在润扬大桥可靠度评估中的应用

为了定量研究大跨桥梁在外界随机因素作用下的结构安全性,实现在线状态的可靠度评估,利用可靠度的随机有限元法对润扬大桥悬索桥在正常运营和损伤等多种工况下的结构可靠度进行了数值模拟和可靠度评估。分析中采用蒙特卡罗重要抽样法和中心复合响应面法的联合算法作为数值模拟的基本工具,介绍了联合算法的具体实现途径、随机变量的参数定义并对大跨桥梁基于可靠度指标的评估准则进行了讨论。得到了多个随机变量的概率灵敏度、主要失效模式所对应的可靠度指标及其相应的状态等级。算例分析结果表明,基于随机有限元的可靠度分析方法可以较好地描述大跨桥梁的非线性特征,联合算法的应用提高了可靠度分析的效率和精度,其结果为润扬大桥悬索桥的状态评估和健康监测提供了参考。     

打入式直桩发生偏斜后竖向承载力分析

桩体的设置常常发生一定的偏斜,对竖向承载力有一定的影响。通过对发生偏斜试桩的偏斜曲线分别按假设曲线和现场实测进行的对比分析,并把曲桩看作曲梁,根据曲梁理论对偏斜桩体进行了分析,建立了平衡方程和物理方程,分析了曲桩在竖向荷载作用下的变形和弯矩。得到以下结论:桩体由于施打而发生的弯曲在桩体中产生的残余应力可以忽略不计;桩顶竖向荷载作用下桩身的弯矩同桩的偏斜曲线有重要关系,桩顶处的曲率较大时,桩身的弯矩在工程中是不能忽视的。     

基于数字图像的非均质岩土工程材料的数值分析方法

提出了一种基于数字图像的非均质岩土工程结构的二维数值分析方法。以花岗岩为例,先将岩石的表面图像导入计算机中;然后采用基于彩色空间的数字图像技术将组成花岗岩的几种主要材料:长石、石英和黑云母一一分辨出来并再现岩石的细观结构;再通过一个简单的线性转换,将图像细观结构转换为矢量细观结构;最后,岩石的矢量细观结构可以与数值计算方法--有限元法或有限差分法结合,从而实现非均质岩石材料的力学分析。采用有限差分法FLAC程序来分析岩石的破坏过程。传统室内试验数值模拟表明材料的细观结构对应力分布和破坏模式有着明显的影响,基于数字图像的数值分析方法可以真实地实现岩土工程材料的非均质分析。     

关于土的残余强度的概念、测试与应用

土的残余强度是一个比较稳定的值,它对现实中土体的长期稳定性有重大意义.     

澳门历史建筑的保护与利用实践

2005年澳门中请世界遗产获得成功,这和澳门长期致力于历史建筑的保护与利用密不可分.在中葡文化碰撞和交叠的澳门,历史建筑得到很好的保护和利用.文章论述了澳门近年来在历史建筑保护与利用方面的发展与实践,希望给业内人士带来一定的启示.     

南部非洲房地产开发风险分析实例

南部非洲的建筑市场潜力很大,进入这片土地的开发商和承包商越来越多,竞争越来越激烈。房地产开发和工程承包的成功与否在很大程度上取决于风险管理的水平。本论文阐明了南部非洲房地产开发风险分析的主要环节和内容,分析了南非一个中成本住宅项目在开发过程中遇到的风险事件以及风险发生的原因,以期为将进入和已经进入非洲的房地产开发商和承包商提供一些可供参考的风险管理信息。     

On the flame height definition for upward flame spread

Flame height is defined by the experimentalists as the average position of the luminous flame and, consequently is not directly linked with a quantitative value of a physical parameter. To determine flame heights from both numerical and theoretical results, a more quantifiable criterion is needed to define flame heights and must be in agreement with the experiments to allow comparisons. For wall flames, steady wall flame experiments revealed that flame height may be defined by a threshold value on the wall heat flux. From steady wall flame measurements, three definitions of flame height from wall heat flux are retained: the first is based on the continuous flame while the two others are based on threshold values of 4 kW/m² and 10 kW/m². These definitions are applied to determine flame heights from a two-dimensional time-dependent CFD model used to describe flame spread on a vertical slab of PMMA. Results show that the predicted flame heights are consistent with the available data of the literature. Defining flame height by threshold values on the wall heat flux of 4 and 10 kW/m² allows the correlation of the wall heat flux in terms of (x−x_p)/(x_fl−x_p), which is the dimensionless characteristic length scale for upward flame spread. It is also found that the continuous flame is not a characteristic length for the heat transfer to the unburnt fuel and is not really appropriate to define flame height in upward flame spread.     

An exergy application for analysis of buildings and HVAC systems

The paper presents an extended method for exergy analysis of buildings and Heating Ventilation Air Conditioning (HVAC) systems, according to an energy demand build-up model from the building side to the energy supply side. The HVAC systems comprise a thermal energy emission and control system, a thermal distribution system, an electricity distribution system and an energy conversion system. Energy and exergy that are required by a building and a HVAC system are posed into the external part and classified by different forms of energy carriers. The external part is out of the boundary of the study. The method is illustrated with an office building equipped with low-temperature heating and high-temperature cooling systems situated in the Netherlands. Thermal exergy and thermal energy demands of the building and thermal energy and thermal exergy losses occurring in the HVAC systems are discussed. The building and the HVAC systems to be considered meet standard Dutch energy performance regulations. Nevertheless their overall exergy efficiencies are low in both cases (17.15% and 6.81% subsequently). The exergy analysis also pinpoints that the thermal energy emission and control system and the energy conversion system are the main causes of the exergy inefficiencies in the heating and cooling cases, respectively.