A lagrangian dispersion model for calculating concentration distribution within a built-up domain

A Lagrangian model to study the dispersion of pollutants between urban buildings is described. The flow field is supplied by an objective analysis (Rockle (1990) Ph.D. thesis, Vom Fachbereich Mechanik, der Technischen Hochschule Darmstadt, Germany) and is adjusted to satisfy the continuity equation. From the resulting; mass consistent field the Lagrangian diffusion parameters are eliminated. A 3-D Lagrangian diffusion model in a nonhomogeneous field is applied to calculate the pollutant distribution between the buildings. Several examples are studied and compared to wind tunnel measurements.     

An experimental study on shrinkage of earth plaster with natural fibres for straw bale buildings

In this paper, a series of laboratory tests on shrinkage of plaster materials are presented. The plaster materials consist of cohesive soil, sand and different natural fibres. Three types of fibres, wheat straw, barley straw and wood shavings, were used as reinforcement in the tests. The shrinkage behaviour of earth plasters was studied by laboratory tests for different compositions and under different curing conditions. The specimens of plaster material were dried under a constant temperature of 30, 50 and 70°C, respectively. The effect of the following factors on shrinkage was investigated: temperature, soil composition, fibre type and fibre content. It was established that shrinkage crack formation decreases with increasing fibre content and increases with increasing soil content. In general, it was also found that lower curing temperature and higher fibre content are to be preferred to improve the performance of earth plasters.     

污水处理工程中的裂缝控制

讨论了在污水处理工程中,钢筋混凝土结构裂缝产生的原因,提出了具体的裂缝控制措施。     

高层建筑火灾情况下利用电梯疏散的案例研究

随着我国城市化进程的加快，城市人口日益增多，高层建筑数量剧增，其所面临的安全疏散问题也越来越突出。在高层建筑火灾中，楼梯疏散是人们常推荐使用的逃生工具，但是它存在疏散时间长的弊端。高层建筑拥有一定数量的电梯，充分发挥垂直交通的优势，已经成为“9．11”之后国际火灾科学研究的热点。事实上，在过去发生的火灾案例中，已经有许多人员利用电梯来进行安全疏散。选取某高层住宅火灾为研究案例，采用电梯疏散ELVAC模型和楼梯疏散SIMULEX模型，分析了电梯数量、人员分布等对电梯疏散的影响。研究结果表明，采用楼梯和电梯相结合的混合疏散方式可以有效地提高疏散效率。     

The relationship between daylight and happiness for women in residential districts of Isfahan,Iran

This study explores the relationship between daylight exposure in urban residential units and the mood/happiness of nonworking female residents (housewives) in Isfahan, Iran. A growing body of evidence points to the physiological and psychological benefits of daylight, yet few studies have focused on the relationship between residential daylight and women's mental health. A cross‐sectional study was conducted using two‐stage random cluster sampling of nonworking female occupants of buildings in four residential districts. Mood/happiness was determined using the Oxford Happiness Inventory and the Fordyce Happiness Inventory. Spearman's rank correlation analysis was used to determine the relationship between the variables. A significant relationship was found between residents’ happiness and the amount of daylight in their residential units (Oxford Inventory, r = 0.68, P < 0.05; Fordyce Inventory, r = 0.53, P < 0.05). The findings suggest that features of physical residential environments, such as daylight, may be linked to the happiness of housewives. Persons belonging to various demographic groups who spend the majority of their time indoors (e.g., housewives, children, elderly individuals, and people with disabilities) are most dependent on architecture and environmental design for their well‐being, and therefore, are most affected by design decisions.     

不同温度下超高层建筑窗口火蔓延模拟分析

为揭示不同温度条件对凹型超高层建筑窗口羽流火焰融合高度的影响,采用火灾动态仿真模拟软件PyroSim,构建不同温度条件下凹型超高层建筑的火灾模型;分析该模型下竖向连续多窗口温度分布等温线及温度曲线。结果表明:在不同室外温度条件下,纵向连续3窗口比2窗口在达到危险温度540℃时,火焰融合高度上升4.5~5.9 m;在达到危险温度350℃时,火焰高度上升11.0~13.3 m。纵向连续4窗口比3窗口在达到危险温度540℃时,火焰融合高度上升3.0~3.4 m;在达到危险温度350℃时,火焰高度上升7.8~9.5 m;对于凹型超高层建筑,室内外温差越大,火焰融合高度越高;从纵向连续3窗口开始,火焰融合高度增长趋势下降。     

Optimal design for water conservation and energy savings using green roofs in a green building under mixed uncertainties

Most water conservation and energy saving strategies for residential homes and commercial buildings have higher initial capital investment than traditional ones. Yet, the added benefits of these “green” building strategies should outweigh the increase of initial capital cost at the end of the house lifetime. Using green roof systems to cool houses gives rise to uncertainties from local precipitation patterns and the unstable market related costs and benefits. The optimal area of green roof to balance cost, benefit, and risk remains unknown. To achieve such a complex systems analysis, a grey stochastic programming model was prepared to address the optimal design strategies under mixed uncertainties. Such a cost-benefit-risk trade-off model was formulated for this study through an optimization framework to retrieve the optimal design strategies with respect to a typical Florida residential home (shingle and metal roofs). It is particularly designed to synergistically integrate a green roof with beneficial reuse of gray water and stormwater while achieving some degree of energy savings. The study identifies the optimal green roof area that keeps within the cost of a conventional home over a specific life time, such as 50 years. Research findings show that as the reliability level associated with the chance constraint was decreased, the upper bound of the green roof area did not vary much for either shingle or metal roofs. The lower bound was found to decrease in the same situation, however, due to the higher minimum cost of the cistern in relation to the greater volume of expected rainfall, forcing the required green roof area to decrease.     

焦化工业场地建筑物和生产设施表面Pb的赋存特征及健康风险

研究了某典型焦化工业场地建筑物和生产设施表面Pb的污染特征及其存在的健康风险.在该场地选择了56个建筑物和生产设施,采用美国环保局(United States Environmental Protection Agency,US EPA)的擦拭取样方法,采集了94个擦拭样品,分析了建筑物和生产设施表面Pb的含量,目的是...     

建筑间距对大气流动及输移特性影响的模拟研究

采用修正的k-ε湍流模型对不同建筑间距情况下的大气流场、污染物浓度场进行模拟研究。模拟研究结果表明,气流遇到建筑物发生绕流,风速为3m/s的气流在建筑物附近的最大抬升速度达到1.98m/s,气流绕过建筑物后湍动能增强,建筑物后污染物的扩散区域变大;建筑物的布局对气流流动和污染物浓度分布有着很大影响,在不同建筑间距情况下,建筑物尾流区的流场形态有着明显的不同,尾流区内污染物的分布也存在差别。研究结果对认识多个建筑物附近的气流和污染物分布有重要意义。     

A scoping study on the costs of indoor air quality illnesses: an insurance loss reduction perspective

The number of indoor air quality (IAQ)-related health complaints in commercial buildings, and the frequency of litigation over the effects of poor IAQ is increasing. These increases have ramifications for insurance carriers, which pay for many of the costs of health care and general commercial liability. However, little is known about the actual costs to insurance companies from poor IAQ in buildings. This paper reports on the results of a literature search of buildings-related, business and legal databases, and interviews with insurance and risk management representatives aimed at finding information on the direct costs to the insurance industry of poor building IAQ, as well as the costs of litigation. The literature search turned up little specific cost information, but indicated that there is a strong awareness and growing concern over the “silent crisis” of IAQ and its potential to cause large industry losses. The source of these losses includes both direct costs to insurers from paying health insurance and professional liability claims, as well as the cost of litigation. In spite of the lack of data on how IAQ-related health problems affect their business, the insurance industry has taken the anecdotal evidence about their reality seriously enough to alter their policies in ways that have lessened their exposure.