磁悬浮列车用定子固定梁型材开发

浦钢公司开发生产的上海磁悬浮列车用定子固定梁(∏)型材采用的材质牌号为S355N,正火状态交货.该型材的断面单重达到126 kg/m,属巨型材.在型材的孔型设计中,为了解决中型轧机轧制巨型材受到轧机能力等各方面条件限制的问题,通过对型材的断面分析和合理划分,简化了轧制力的计算方法,为孔型设计中的压下量分配提供了计算依据.采用多道次、小压下量以及合理孔型系统,解决了型材总延伸系数小的成形问题.     

大型"∏"字形型材的模具设计与优化

由于"∏"字形型材一般都是外形大、壁厚薄、形状复杂,且形位偏差的要求特别高,因此模具设计、加工质量将直接影响到型材的成形、交货周期及其他技术要求。以型材编号为EL5711为例,探讨了挤压模具的设计优化问题,从而解决了型材的平面间隙、弯曲度等难题,确保了生产的型材满足用户的需求。     

济钢一小型坯料结构设计与优化

为了确保全连轧改造后的小型材定尺率、成材率等技术经济指标不断提高,对各规格小型材坯料结构重新设计,并不断优化,使各规格小型材坯料结构更加合理.     

工业铝型材挤压模具的设计

根据多年从事铝型材挤压模具设计的实践经验,在设计建筑用铝门窗型材模具的基础上,又进一步扩展到工业用铝型材模具设计领域,所谈的工业铝型材涉及到汽车制造用型材、工业用型材、民用散热器型材等等。通过论述几种典型型材的模具设计实例,分别描述这些特殊模具的结构形式以控制和调整金属的变形流动速度,从而获得高质量、断面复杂、挤压成形困难的多种工业用铝型材。     

6061合金汽车控制臂型材的工艺研究

针对汽车控制臂型材对组织均匀性、力学性能以及耐磨性的严格要求,从合金成分设计、提升铸锭质量以及保证型材的综合性能等方面开展研究,成功研制出符合要求的汽车控制臂型材,并广泛应用于日系汽车中。     

铝型材断面设计及可挤压范围分析

铝合金型材是一种用途十分广泛的材料，其可挤压性、生产效率、产品质量和用途等均与型材断面形状和尺寸有关。本文着重讨论铝合金型材的断面设计原则、影响形状与尺寸的主要因素以及可挤压的尺寸范围等，为铝合金型材的高效、优质、低成本生产创造有利条件。     

立柱型材模具的改良设计

介绍了立柱型材的改良设计方法,改良后的设计使模具受力结构更趋合理,模具寿命延长,型材成形更稳定。     

铝合金双孔挤压模具设计及仿真模拟分析

本文以6063铝合金空心截面型材为例,通过对铝合金型材的分析,结合平面分流组合模各个组件的结构要素、设计要点,设计了双孔挤压模具并校核了模具的强度;在Pro/E绘图软件上建立模具的三维仿真模型;在HyperXtrude有限元分析软件上对三维仿真模型进行了网格划分,设定边界条件和参数,模拟该型材的挤压过程并收集该型材在工作带处的温度分布、流速差异和变形程度等信息。     

人行天桥用6082合金型材的综合性能提升

根据人行天桥用6082合金型材的表面质量和力学性能要求,结合6082合金型材的生产实践,从合金成分设计、均匀化工艺、挤压工艺和在线淬火工艺等方面进行研究分析,探索出最佳工艺,提升了人行天桥用6082合金型材的综合性能。     

铝合金建筑型材挤压模的设计

简单介绍了几种铝合金建筑型材挤压模的设计实例.并阐述了铝合金型材宽展分流挤压模、变宽度宽展导流模、双孔分流挤压模的结构设计特点.     

Sources of Changes in Design–Build Contracts for a Governmental Owner

In recent years, many U.S. federal, state, and local governments have been authorized to use the design–build method of project delivery instead of the traditional design–bid–build method. Recent studies have not been definitive on the cost advantage of design–build for governmental owners. There are fewer change orders in design–build due to design errors because the designer (architect/engineer) and contractor are one entity, but there are other causes of change orders. Some literature suggests that changes requested by the owner of the facility are greater with the design–build method. This research examines the causes for construction-phase changes in 14 design–build and 20 design–bid–build projects. Total changes, expressed as number per contract, cost per contract, or percentage of original contract, were significantly lower in design–build. Fewer design errors in design–build accounted for this advantage. The number of owner-requested changes was significantly greater in design–build. The cost of owner-requested changes, averaged over all the projects, was significantly less for design–bid–build. The differences in changes due to differing site conditions were not significant. The concept that there are more owner-requested changes in design–build projects is supported by this research.     

Collaborative Planning and Scheduling of Interrelated Design Changes

During the detailed design stage of a building project, a vast amount of mostly interrelated design information is generated and communicated among specialists from several disciplines. Changes in some design information are inevitable due to the iterative nature of the design process. In many cases, when the design of a building component is modified by one discipline, this change affects the design of many related building components that are the responsibility of several other design disciplines. Commitment and resources are needed to accommodate such design changes to maintain compatibility among all the design information. Otherwise, incompatibility errors become embedded in the design information leading to numerous problems during the construction of the project. This paper presents a computer-assisted methodology that helps design managers in planning and scheduling changes with interrelated effects on the design information.     

Design Structure Matrix Implementation on a Seismic Retrofit

A void exists in development of design theory methodology within the structural engineering community. This void hampers efforts to resolve performance deficiencies including cost over-runs, unplanned rework, and suboptimal design. In manufacturing, product design and production improvements have resulted from implementation of the design structure matrix (DSM) methodology. DSM offers a means to represent, analyze, and decompose complex systems in order to improve their performance. DSM use within the architecture engineering construction (AEC) industry has been sporadic and focused primarily in the U.K. Where applied, DSM has proven effective at helping AEC design teams streamline processes to address nonlinearity (nonsequential information flows) introduced by iteration and complexity in design. When a DSM reveals iteration and highly dependent work, group brainstorming, collocated design sessions, rapid feedback, set-based design, and collaborative design aids can be used to increase overall team effectiveness. This paper examines a case study where DSM-based planning software was used on a seismic retrofit project to drive process improvement in design management. DSM correctly identified iterative activities central to design and provided the following; (1) a common vocabulary to discuss rework in the context of a multidisciplinary design team; (2) a rational method to schedule team collocation and brainstorming efforts to maximize their benefit; and (3) a means to consider iterative activities (and associated hand-offs) in design work structuring.     

Identifying a Design Management Package to Support Concurrent Design in Building Wafer Fabrication Facilities

Concurrent design is commonly used in building a semiconductor wafer fabrication facilities to shorten projects. Current practice in managing a design schedule involves preset milestones that represent percentages of completion. Such a simple control scheme does not provide sufficient information to support concurrent design. This study presents an analytical model that applies a cluster identification algorithm to separate the work of designing a multisystem project into management packages that support concurrent design. Tasks within a package have strong informational dependency relationships on each other, and are not suited for concurrent design. Tasks of different packages have weak dependency relationships on each other, and are suited for concurrent design. Tendering design work based on these packages may reduce the number of design interfaces between participating design firms. Possible application of the model includes the management of design schedule, design contract tendering, and design information flow.     

Concept for Type-Local Instance–Global Instance Object Modeling and Application to Structural Design of Buildings

Rational data modeling is prerequisite to the computerization of design, and the use of design information in the subsequent work, in areas such as cost estimation and construction. In particular, the structural design of buildings consists of a long series of unit steps and is nonprocedural and data intensive compared with structural analysis problems that are procedural and computation intensive. Hence, there is a need to investigate the characteristics of the problem and to structure design information properly to effectively manage it in the structural design process. This paper discusses modeling concepts for managing design information efficiently and supporting the design process effectively. Type-local instance–global instance object modeling is the conceptual backbone of the model in this study and provides consistent modeling of structural components including not only primitive members such as beams and columns, but also composite elements such as floors, frames, and even whole buildings. This paper also provides core and extended object concepts for classifying structural design information into an overall design and for processing dependent temporary stages in the design. Foundational and application object concepts are introduced for extending the model to various types of structures. An integrated structural design system for buildings is developed based on these modeling concepts, and finally a brief discussion of the application of the object model throughout the entire structural design process in the integrated structural design system is given. It is expected that the modeling concepts proposed in this research can be applied to a range of other engineering applications.     

Optimal Design in the Presence of Modeling Uncertainties

The integration of modeling and simulation tools with robust and efficient methods of optimal design offers a rational approach to explore new concepts and designs. However, a widespread adaptation of these tools in the industry design environment will require that they incorporate a systematic analysis of uncertainty in all aspects of the design process. A lack of confidence in designs generated in a simulation-based approach is the result of uncertainties in the predictive capabilities of physics-based models used in the simulations, and poor representation of uncertainties and their propagation in a coupled systems engineering design problem. A data- and knowledge-lean environment, typical of a design process involving novel concepts, further exacerbates the situation; design engineers often make gross assumptions about distributional information of random variables and parameters, thereby adding to the uncertainty associated with the design results. The paper focuses on numerical and analytical tools by which to model uncertainty and risk in a simulation-based design environment, including cases where the uncertainty does not conform to standard probabilistic distributions. A specific focus of the modeling effort is an approach to establish confidence intervals for response predictions available from analytical and numerical models, as well as surrogate approximations used in the design process. Innovative adaptations of formal optimization methods in a nondeterministic design setting are discussed, including design problem formulations that examine the nondeterministic design problem in a multicriteria optimization framework. Simple design problems are used to illustrate the concepts and to underscore the deficiencies in a purely deterministic approach to the design problem.     

对展示设计的探讨

展示设计在当今信息时代应用越来越广泛，其实用价值越来越高，设计效果备受社会关注。本文论述了展示设计的基本概念和特性，结合笔者多年设计工作经验和体会提出了展示空间设计的基本原则和在展示环境设计中对功能空间的处理方式，供展示空间设计者在设计工作中借鉴。     

基于UGNX的铝型材挤压分流模设计

在铝合金空心型材生产时,平面分流模得到广泛的应用。由于模具结构复杂,应用传统的二维模具设计方法建立模具模型,存在很多不足。实体模型是进行有限元分析和优化设计的基础。以LX0349号型材为例,介绍了UGNX在铝材挤压分流模实体建模中的应用,从而为进一步进行有限元分析和模具优化设计打下了基础。     

浅谈结构设计中的质量管理

本文通过对建筑结构设计前期质量管理,设计过程质量管理,设计后期质量管理的阐述,分析了建筑结构设计全面质量管理的过程,简洁透明、便于掌握。有效地执行建筑结构设计全面质量管理是设计单位在同行业竞争中的关键因素。     

Aesthetics and Philosophy in Bridge Design in Japan

This paper investigates the background of current trends in bridge design in Japan in the context of common design practice, which distinguishes architecturally, industrially, and structurally led designs. Because the philosophy of engineering design has not been recognized outside the rational philosophies of structural mechanics, this paper introduces a method of design and evaluation that is based on the application of architectural philosophies for bridge design. While current criticism is basically devoted to the evaluation of structural and visual qualities of bridges, the method illustrated by the case study of Japan Bridge, includes the aesthetic and ideological analysis of bridge design, which, like the analysis of building design, draws on subjective design concepts. Unlike in the conventional critical apraisal of bridge design, this method allows for the reintegration and evaluation of the structural and architectural values of bridges. Considering the complexity of comtemporary Japanese bridge design, landscape-oriented, structure-oriented, preservation-oriented, thematic, and symbolic trends in bridge design have been distinguished. Rediscovering philosophy in bridge design can be an effective way to invoke a wider response to the creativity of bridge designers.