Mini‐blasting for repair work

High chloride content of the concrete had led to corrosion of reinforcement in the brackets supporting the access balconies of a block of flats in Copenhagen; also affected were parts of the balcony decks and some wall panels. Widespread replacement of the suspect components was chosen, including re‐casting of the support brackets in situ. How the old concrete of the brackets was removed by controlled local blasting is described by a member of Demex consulting engineers, who acted as explosive demolition consultants to this project.     

悬挑脚手架型钢悬挑梁的设计计算

随着高层建筑的日益增多,建筑结构的日趋复杂,工字型钢悬挑脚手架以其投入低、周转快、节约工期等特点广泛应用于实际工程中.通过工程实例,在对比新旧规范的基础上,选用更切合实际的计算模型,对确保钢悬挑脚手架安全的关键部位型钢悬挑梁进行设计计算分析,形成计算模板,供实际工程参考.     

城市供水管网的试验模型研究

为便于研究城市供水管网中管流的水力特性和水质情况,依据水力相似原理,构建了与实际供水管网等效的管网试验模型.先分析并确定了压力供水管网符合欧拉相似准则,然后基于管流的变态相似理论,推导出管网原型与其试验模型间各物理量的相似关系.通过选定合适的几何比尺,建立供水管网试验模型.应用EPANET软件模拟管网模型运行工况,得到各节点的水头,据此调节各用户端电动球阀的开度,实现用户节点流量的试验模拟,同时应用EPANET软件模拟管网原型的运行工况.通过对比管网试验模型和原型中各相应管段的流速,验证了试验模型和原型能够很好地满足相似关系,表明该建模方法是可行的.     

粉煤灰砖生产工艺技术综述

当前国内建筑施工中大量使用轻质、高强、绿色环保以及复合型新型墙体材料。粉煤灰砖是墙体材料中的主导产品,它符合节能、环保、促进墙体材料改革的目标,有着广阔的发展应用前景。国内粉煤灰生产工艺主要有烧结工艺,蒸压工艺,免烧免蒸压工艺等。常温发泡砖仍处于研发中。     

对独立基础在不同地基承载力条件下受剪承载力计算要求的建议

通过对不同地基承载力基础进行计算抗剪,提出独立基础抗剪的设计要求。     

缓黏结预应力混凝土梁的设计

缓黏结预应力技术是近年来国内发展起来的一项新的预应力技术,它综合了无黏结预应力和有黏结预应力两种体系的技术特点,是预应力技术的新发展,论文结合北京报业集团新闻采编中心项目缓黏结预应力混凝土梁的设计,阐述了缓黏结预应力技术原理;说明了缓黏结预应力混凝土梁的承载力、裂缝和挠度的计算方法;提出了缓黏结预应力构件设计及施工中的注意问题。     

Territorial Cohesion Discourses: Hegemonic Strategic Concepts in European Spatial Planning

The paper ¹ 1. The elaboration of this paper was supported by the European Seventh Framework Programme under grant agreement no 217157 (Social Polis). Further information on www.socialpolis.eu. reflects on the EU objective of territorial cohesion, exploring its role as a catalytic concept around which several (spatial and non-spatial) discourses and policy practices have been generated in European Spatial Planning. The assumption is that these discourses act as cultural constructions which define the strategic selectivity of EU institutions and strategically orientate the selective calculation of stakeholders' behaviour and their policy-making activities. The paper further explores the contents of spatial planning discourses related to the territorial cohesion objective analysing the EU official literature and highlighting general trends and main focuses. It provides an interpretative framework based on four categories: “principles”, “territorial dimensions”, “strategic policy options”, and “governance aspects”.     

对优化建筑工程成本核算方法的探讨

对建筑工程成本核算的工作内容进行了总结,分析了成本核算工作的必要性,并结合工程实例,就如何科学的进行成本核算作了探讨,以期不断地完善成本核算体系,促进建筑行业发展水平的提高。     

三联吡啶衍生物Hg2+探针的合成、离子识别及量化计算

通过Suzuki偶联反应,分别将9-己基-9H-咔唑基团和三苯胺基团引入4'-(4-苯基)-2,2',6',2″-三联吡啶结构中,设计合成了两种具有D-π-A结构的三联吡啶衍生物(Tpy1和Tpy2),并经熔点、核磁共振、质谱及元素分析对其结构进行了表征。Tpy1和Tpy2对Hg2+比其他金属阳离子具有更好的选择性,可通过紫外分光光度法或紫外灯下肉眼观测对二氯甲烷溶液中的Hg~(2+)进行有效识别。密度泛函理论(DFT)量化计算结果表明,当探针与Hg~(2+)结合后,其分子内电荷转移(ICT)效应增强,吸收光谱红移31 nm。此外,探针分子中所连接的不同的供电子芳香基团可影响其对Hg~(2+)的识别效果,Tpy1和Tpy2检测限分别为2.51×10~(-6)mol/L和4.40×10~(-6)mol/L。探针分子对Cu~(2+)也有响应。     

Nonsmooth model for dynamic simulation of phase changes

Dynamic modeling of processes involving phase changes can be challenging due to changes in the model equations caused by appearance and disappearance of equilibrium phases. Dynamic simulation of these processes requires the ability to detect the change in the number of phases and adapt the model to the new phase regime on the fly. In this work, an easy‐to‐use nonsmooth model for dynamic simulation of processes with vapor‐liquid equilibrium is presented. The presented model does not introduce any auxiliary variables or equations, nor does it require solution of an optimization problem to determine the new phase regime during the dynamic simulation. It can therefore be used for comprehensive simulation of, e.g., distillation columns, where the number of phases present can change during startup and shutdown. The nonsmooth model is illustrated through examples of an evaporator and a distillation column. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3334–3351, 2016