SHS法陶瓷衬管的研究现状及应用前景

回顾了自蔓延高温合成陶瓷衬管的发展历史，对国内外的研究现状进行归纳总结，介绍了离心ＳＨＳ法生产陶瓷衬管的工艺特点及产品性能，展望了离心ＳＨＳ陶瓷衬管的应用前景。     

Economic Model to Optimize Underground Utility Protection

The need for better protecting our vital infrastructure from being damaged or destroyed has received increased attention since the terrorist attacks on September 11, 2001. The tragedy of having thousands of innocent people die before the eyes of an entire nation awakened people to the reality of “managed” attacks of unthinkable magnitudes. However, tragedies of a smaller scale are a daily occurrence but accepted as “collateral damage” of work in an unsafe environment. This paper presents a cost-benefit analysis to address the question of how much money should be spent in protecting underground utilities from damage. During the study of an actual incident it was found that the total costs of such accidents are vastly underreported because only costs for emergency responses and repair are tallied up. This paper makes the case that a comprehensive approach for assessing the total economic impact of such incidents on the public, business, and government is the critical stepping stone to a mathematical optimization of expenditure for damage prevention. In addition, the reader will quickly realize that the use of the presented optimization model provides theoretical underpinning for the engineering profession in its effort to better protect our critical infrastructure from terrorist attacks.     

Finite elements in the analysis of pressure vessels and piping-a bibliography (1976–1996)

The paper gives a bibliographical review of the finite element methods (FEMs) applied for the analysis of pressure vessel structures/components and piping from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore the aim of this review is to give the reader an encyclopaedic view of the differnt possibilities that exist today for the finite element analysis in the fields of pressure vessels and piping. The bibliography at the end of the paper contains approximately 1900 references to papers, conference proceedings and theses/dissertations on the subject that were published in 1976–1996. These are classified in the following categories: linear and non-linear, static and dynamic, stress and deflection analysis; stability problems; thermal problems; fracture mechanics problems; contact problems; fluid-structure interaction problems; manufacturing of pipes and tubes; welded pipes and pressure vessel components; development of special finite elements for pressure vessels and pipes; finite element software; and other topics. Also finite element software, general purpose and special purpose codes, used for the analysis of pressure vessels and pipes are briefly discussed and presented.     

粉喷桩及其应用

简介了目前采用的粉喷桩的基本工作过程。叙述了水泥粉喷桩的加固机理：①水泥的水解和化学反应；②离子交换和团粒化作用；③水泥的凝结与硬化；④碳酸化反应。介绍了粉喷桩的应用范围，并结合工作概况、场地概述、地基加固方案选择、粉喷极的设计和质量检查等具体过程给出粉喷桩的具体应用实例。     

用硫铁矿焙烧粉尘制硬质塑料管的研究

用硫酸厂硫铁矿焙烧后的粉尘掺入聚氯乙烯中，用挤出成型法挤制硬质聚氯乙烯塑料管，以扩大聚氯乙烯塑料的用途。     

加快创新开发,开拓聚氯乙烯压力管道系统的新局面

近年来聚氯乙烯管道取得了重大进步。PVC-M管材(改性聚氯乙烯管材)、PVC-O管材(取向聚氯乙烯管材)兼有非凡的强度和韧度,和传统的硬聚氯乙烯管材比可以采用较高的设计应力,显著地节约材料。     

基于PWM的相变热管温度分段控制系统设计

针对卫星热控制中常用的相变热管材料,设计了一个大干扰下的温度控制系统,以获得相变热管在恒温条件下的热性能参数。控制策略是将棒棒控制、模糊控制与仿人智能控制相结合,以PWM方式控制高速开关阀通断时间以控制冷却液流量大小,实现了大干扰下温度的多模式分段精确控制。提出了两点创新:将基本模糊控制改为增量式模糊控制,把误差变化率作为仿人控制的一个控制对象。实验结果表明,整个温度控制系统具有响应速度快、超调量小、调整时间短等优点,稳态误差小于0.15℃,满足实际要求。     

Adhesive bonding of stainless steel water tubing

The use of an adhesive to bond stainless steel water tubing, allowing stainless steel fittings to be employed, is considered and compared with the more conventional use of compression or capillary copper fittings together with a soft solder. Tests carried out to determine environmental effects on adhesively bonded stainless steel tubing suitable for domestic water supply, and the strengths of these joints, are described. It has been found that acrylic anaerobic adhesives are suitable for bonding tubing carrying cold water, the joints attaining superior strength to the copper-soldered ones; a reasonable degree of flexing can also be tolerated. It would appear that certain selected adhesives may also be used in joints carrying hot water.     

管道内穿管修复技术的应用

为解决城市地下金属管道由于常年连续运行时间长、防腐技术落后情况下产生漏铁、穿孔腐蚀等问题,阐述了利用管内穿管的先进技术解决地下管道的修复问题.该技术经应用后,施工质量满足使用要求,具有推广价值.