玻璃钢加砂管在软土地基中的应用

主要分析并指出了新型材料在软土地质环境中的应用，并提出了解决软土中存在问题的方法，保证了新型材料在不同的条件正常施工，从而保证了管网的安全运行。     

A novel thermoelectric refrigeration system employing heat pipes and a phase change material: an experimental investigation

This paper presents results of tests carried out to investigate the potential application of heat pipes and phase change materials for thermoelectric refrigeration. The work involved the design and construction of a thermoelectric refrigeration prototype. The performance of the thermoelectric refrigeration system was investigated for two different configurations. The first configuration employed a conventional heat sink system (bonded fin heat sink) on the cold side of the thermoelectric cells. The other configuration used an encapsulated phase change material in place of the conventional heat sink unit. Both configurations used heat pipe embedded fins as the heat sink on the hot side. Replacement of the conventional heat sink system with an encapsulated phase change material was found to improve the performance of the thermoelectric refrigeration system. In addition, it provided a storage capability that would be particularly useful for handling peak loads and overcoming losses during door openings and power-off periods. Results showed that the heat sink units employing heat pipe embedded fins were well suited to this application. Results also showed the importance of using a heat pipe system between the cold junction of the thermoelectric cells and the cold heat sink in order to prevent reverse heat flow in the event of power failure.     

Development of a reference strain approach for assessment of fracture response of reeled pipelines

As a result of recent increase in exploitation of hydrocarbon resources in harsher environments and also installation techniques which utilize the materials plastic deformation capacity, accurate assessment of fracture response of pipelines subject to large plastic strains (e.g., typical of reeled pipes) has attracted particular interest nowadays. In this paper, an approach, based on the evaluation of the J-integral, is developed for assessing the integrity of such pipelines, manifested in a model of a pipeline with a circumferential part-through crack subjected to plastic bending. The proposed approach is an extension of the reference strain method developed earlier by other researchers, and takes advantage of the displacement controlled loading nature in such pipes (thus being suitable for Strain Based Design methodologies), and the resulting high strain levels, which often cause fracture response of the material in the plastic regime. The developed formulation relates the fracture response of the pipe (in terms of the non-dimensionalized J-integral) as a linear function of the axial strain in the pipe at its uncracked state. A series of 300 3D nonlinear finite element models using the ABAQUS software were analyzed in preparation of the equation that could assess the fracture response of such pipes with great accuracy. The resulting equation, calibrated by the finite element results, can predict the fracture response of pipes with a maximum error of 2% for a practical uncracked material strain range of 1.5% ? ε_unc ? 4%.     

Tubular guidance systems for daylight: UK case studies

Tubular daylight guidance systems (TDGS) are linear devices that channel daylight into the core of a building. The experience of some of the first uses of TDGS is explored in actual buildings in UK temperate latitudes. The nature of the systems and the factors influencing the costs and various benefits that contribute value are identified. Lighting systems in working offices, lit by electric lighting and daylight guidance, were surveyed. Data on the physical characteristics of the systems, lighting conditions achieved, and user views were collected. The results formed the input to a cost and value analysis which permitted the economic limits of the systems to be evaluated. A number of daylight and environmental benefits were identified as value items, but the systems were clearly uneconomic in cost terms as presently configured and used. Long-term cost–value was compared with electric lighting alternatives making assumptions about future energy costs and system configurations. Some pitfalls of attempting to integrate innovative technology into existing lighting systems are identified and remedies suggested.

Les systèmes tubulaires de guidage de la lumière du jour (TDGS) sont des dispositifs linéaires qui canalisent la lumière du jour jusqu'au centre d'un bâtiment. L'auteur analyse quelques-unes des premières applications des TDGS dans des bâtiments existants au Royaume-Uni, sous des latitudes tempérées. Il identifie la nature des systèmes et les facteurs qui ont des incidences sur les coûts et les divers avantages qui contribuent à la valeur de ces systèmes. Il étudie les systèmes d'éclairage électrique et de guidage de la lumière du jour utilisés dans les bureaux. Il a recueilli des données sur les caractéristiques physiques de ces systèmes, sur les conditions d'éclairage obtenues et sur le point de vue des utilisateurs. Ces résultats ont servi à une analyse de coût et de valeur qui a permis d'évaluer les limites économiques de ces systèmes. On a identifié un certain nombre d'avantages de la lumière du jour et de l'environnement comme étant des éléments intéressants mais il est clair que ces systèmes ne sont pas rentables en termes de coût tel qu'ils sont actuellement configurés et utilisés. On a comparé l'ensemble coût-valeur à long terme à des alternatives d'éclairage électrique et élaboré des hypothèses sur l'avenir des coûts énergétiques et des configurations de tels systèmes. On a identifié quelques obstacles à l'intégration de technologies novatrices dans les systèmes d'éclairage existant et on a suggéré des solutions.

Mots clés: Mots-clés: technologies alternatives, lumière du jour, retour d'information, systèmes de guidage, conduits de lumière, systèmes d'éclairage, conception de bureaux, evaluation technologique, valeur     

The Measurement of Internal Stress in Electrodeposits

The fundamental principles and underlying methods of measuring internal stress in electrodeposits are reviewed and special attention is given to the bent strip methods. The advantages of the Hoar-Arrowsmith continuous measuring null instrument (Trans Inst Metal Finishing, 1957, 34, 354) are emphasized and a refined theoretical treatment is presented. A comparison is made between the formulae derived by various authors, and approximations involved are examined. Percentage errors, which are frequently quite large, are presented for many of the cases.     

直埋热力管道保温性能试验台的研发

介绍设计开发的新型直埋热力管道保温性能测试台,该装置可实现自动加温、保温层界面测温、自动记录、无人监控。该试验装置具有结构简单、使用方便、可与微机及软件配合使用的特点,符合国家现行有关法规的要求,可以满足国内直埋热力管道型式试验和性能测试的要求。     

浅谈埋地硬聚氯乙烯排水管在市政工程中的应用

本文从管材特性、管道参数计算、施工流程等方面对埋地硬聚氯乙烯排水管在市政工程中的应用进行了叙述,并将其与市政工程中常用的其他管材进行比较,埋地硬聚氯乙烯排水管这种新型管材在市政工程应用中是可靠可行的。     

新型管材在建筑给排水工程中的应用

建筑工程规模的不断扩大促进了建筑给排水工程的增多。建筑给排水新型管材的选择和运用成为了一个重要的热点问题。本文针对新型管材在建筑给排水工程中的应用进行了探讨。     

采用非开挖铺设高精度PE污水管的实践

江苏省太仓市污水改造工程污水管铺设的精度要求很高，而且采用的双壁空心PE管抗拉强度低，对于现有的非开挖铺管技术是一种挑战。介绍了该工程的施工难点以及设计要点，同时对施工中遇到的问题进行了分析总结。