热网直埋管道的失效方式浅析

对直埋供热管道的应力及失效原因进行了分析,对管径相对较大的直埋供热管道的主要失效方式及原因进行了阐述,并探讨了大管径热网直埋供热管道设计中应注意的问题,对直埋供热管道的设计具有参考价值。     

供热管道直埋敷设的计算与设计

介绍了直埋供热管道技术的发展，给出了直埋供热管道的热力计算，设计要点及直埋管道保温结构的做法。     

基于城市直埋式供热管道的可靠性验算

可靠性验算是城市直埋式供热管道的设计和运行管理的重要环节,为了保证直埋式供热管道在一定运行条件下和在规定的时间内安全可靠地运行,本文通过对城市直埋式供热管道的安装技术的介绍,分析了城市直埋供热管道可靠性验算中有关可靠性指标和相关参数,提出了城市直埋式供热管道可靠性验算的方法。利用可靠性设计方法和相应的理论公式,对城市直埋供热管道进行了可靠性验算。研究结果表明：通过管道壁厚和屈服温差两大指标对供热管道的可靠性进行验算,可以明确满足可靠性前提下的最小壁厚值及屈服温差下限,极大地提高了工程质量。     

试论城市直埋供热管道施工技术

介绍了城市供热管道直埋敷设的技术要求和设计方法,从直埋管段基坑开挖、垫层施工、套管安装、直埋供热管安装等方面着手,对直埋供热管道施工技术进行了阐述,并总结了施工中应注意的问题,达到了良好的施工效果。     

《直埋供热管道工程设计》(第二版)简介

《直埋供热管道工程设计》(第二版)由王飞主编,已由中国建筑工业出版社出版发行。在总结2007-2014年研究成果、工程经验,以及国内外先进技术的基础上,对《直埋供热管道工程设计》第一版(2007年版)进行了大篇幅修订,满足了直埋供热管道公称直径增大到1400 mm的实际需要。《直埋供热管道工程设计》(第二版)系统阐述了预制直埋热水保温管直埋敷设的各种力、作用特点及计算;强度理论、安定性理论;直管应力验算,特别是大口径管道的应力验算方法;变径管、弯头的应力     

直埋供热管道热网监测系统

介绍了BRANDES、EMS直埋供热管道热网监测系统。对EMS直埋供热管道热网监测系统的设计进行了探讨。     

直埋供热管网泄漏原因分析及检测

本文从直埋供热管网的设计、施工、运行、材料设备及周边环境等方面,分析了造成直埋供热管网泄漏事故的原因,并提出了相应的应对措施。同时,简要介绍了目前常用的直埋供热管网泄漏检测方法及选择原则。     

室外直埋供热管道设计

随着城镇化进程的不断深化,城镇集中供热系统的完善成为人们生活的客观需求,因此对室外直埋供热管道设计的关注与研究程度提升,近年来我们发现大部分城市在供热管道设计及施工方面存在问题,进而管道崩裂、外部腐蚀、阀门失效等故障频发,极大影响了我们的城镇供热健康迅速发展。本文首先进行室外直埋供热管基础阐述,及从选材和布置原则角度进行切入,其次针对室外直埋供热管道做应力分析与失效,最后根据科学理论研究结合实际经验对室外直埋供热管道设计提出策略、建议,以为相关领域的研究提供有价值的参考。     

直埋供热管道埋深的研究

利用EXCEL表编制了直埋供热管道纵向稳定性验算表,计算了在满足直埋供热管道纵向稳定性验算条件下的管道最小埋深,分析了管道埋深对补偿器、弯头设计选型的影响。     

城镇直埋供热管道技术专题研讨会在京举行

城镇直埋供热管道技术专题研讨会在京举行城镇直埋供热管道技术（以下简称“直埋”），近些年来在我国城镇热网工程中逐步得到应用，各地在开展“直埋”工作时急需了解和解决设计、施工中的许多理论问题和实际操作技术问题，为此中国城镇供热协会技术委员会和建设部城市建...     

Untersuchungen zur Genauigkeit von magnetisch induktiven Betondeckungsmessungen

Assessment of the accuracy of concrete cover measurements using Eddy Current devices The use of non‐destructive testing in civil‐engineering (NDT‐CE) is well established to assess as‐built drawings for existing structures as well as for quality assurance of new buildings or in case of concrete repair. To gain reliable results the choice of the appropriate testing method in combination with the correct data assessment is essential. Hence this article starts with the basics of the two typical testing methods for concrete cover measurement with high precision. Methods based on Eddy Current and based on Radar are different. The strengths and limitations of both methods are presented. In the second part the achievable accuracy of concrete cover measurements using Eddy Current will be assessed for the most important parameters that have been varied in a wide range. It is shown how results are influenced by an improper input of the diameter or by the effect of neighbored rebars. At the end of the article it is shown how the deviation of the results can be minimized using the internal neighboring rebar correction of some of the devices. This article does not intend to be a product test rather the influence parameters of measurements close to reality will be identified and quantified how the accuracy of concrete cover measurements is affected.     

The dilution of waste in the wake of a ship

This paper considers the problem of predicting the dilution of waste which has been discharged into the wake of a moving ship. A theoretical model is developed which relates the dispersion of the effluent field to the intensity of the turbulence created by the movement of the vessel. Specifically, the model describes the dependence of the dilution on the speed, dimensions and specific resistance coefficient of the ship.The new theory predicts that the rate of dilution decreases with time after discharge and, as with the empirical IMCO formula, indicates that dilution is more sensitive to the speed of the ship than the volume rate of discharge of waste.     

Untersuchungen der Auswirkungen eines Vollbrands auf eine Sporthalle

Research of Fire Effects on a Gymnasium An arson attack committed in August 2015 on the gymnasium of the Oberstufenzentrum Nauen school facility built in 2007 led to a full fire and to the complete destruction of the hall. The effects of this fire were recorded with measuring technologies as well as through sampling on‐site. In the course of this, the wooden roof structure was particularly examined and demonstrated a residual load‐bearing capacity in spite of the intensive fire exposure and the resulting significant damage. The remaining support structure of the hall was completely recorded by means of Terrestrial Laser Scanning (TLS) and evaluated in September 2015. Inclinations, cross‐sectional shifts and deformations in the building were able to be calculated with the geodetic measurement method. The results from the laser scanning in combination with the sampling served as a comparison of the theoretical structural evidence with the effects of an actual fire event. In the case of the fire at the Nauen gymnasium, the damage to the load‐bearing capacity was particularly significant in the area of the joining means. The goal of the investigations is a comparison of the technical engineering fire prevention certifications and their theoretical protective effects with the effects of actual fires. This is also a subject of current research projects in the Beuth Hochschule für Technik Berlin, University of Applied Sciences.     

对“建筑”内涵的重新审视与诠释

“建筑”现行内涵的功利与暧昧,是当代建筑粗糙、乏味的主要根源之一.为解决这一问题,首先分析了“architecture”、“营造”与“建筑”三者的内涵.通过将“建筑”与“architecture”及“营造”分别比较,审视了“建筑”的现行内涵;并对其内涵提出了新诠释.     

Landscape Planning at the Regional Scale: an example from North West England

Landscape planning in the UK tends to concentrate on the site and the landscape scales. Concepts of sustainable development and the re-discovered importance of regional-level planning suggest, however, that there is a growing case for the landscape community to develop a regional planning perspective and to engage in wider areas of decision making in order to assist landscape planning goals. These challenges are explored with particular reference to the North West of England which, through the work of an organization called Sustainability North West and the production of a Regional Landscape Strategy, has been at the forefront of regional-level landscape planning in the UK. A brief account is provided of the production of the Regional Landscape Strategy with some reflections on the experience, highlighting some of the problems and potential of the approach. An exploration of the scope for the wider integration of landscape planning within the new regional arrangements is given.     

基于HSS模型隧道近接群桩基础施工影响分析

依托盾构隧道近接侧穿群桩工程建立三维数值分析模型,土体采用小应变硬化(HSS)模型,参数取值借鉴已有研究成果并根据监测位移数据反演,同时考虑土体开挖、衬砌拼装以及盾尾同步注浆等一系列施工工艺措施,并将模拟结果与监测数据进行对比验证,研究了不同工况下地表沉降的形态分布、群桩桩基变形及基桩结构受力,同时考虑地表位移对等代层厚度的敏感性。结果表明:HSS模型能有效预测隧道近接侧穿高架桥桩引起的变形,模拟结果与监测值较吻合; 隧道开挖引起土相对桩产生了滑移,地表沉降及桩身竖向位移在中心线前后各1D(D为管片外径)范围内随推进步数的增加而不断增大,且增加幅度明显减小; 两线推进地表沉降具有叠加效应,最大沉降量增幅达76.8%; 隧道与基桩水平距离越近,引起基桩沉降变化越大,两线推进基桩桩顶沉降增幅达134%; 群桩中各排桩的水平位移变化趋势基本相同,且同排桩的水平位移值相差不大,由于群桩遮挡效应,水平位移值由大到小依次为前排桩、中排桩、后排桩; 桩身水平位移主要在盾构中轴线2.5D范围内,桩身最大水平位移均出现在隧道中轴线附近; 群桩中同排桩桩身附加弯矩及附加轴力沿桩身分布规律相同,桩身最终附加受力与其距离隧道远近有关; 随着注浆充率β的增大,等代层厚度及地表沉降呈线性减小; 穿越段采取的施工工艺方案是有效的,经估算附加弯矩及轴力对桩基承载力的影响在容许范围内。     

论电梯的安全、质量与标准

论述了电梯的特殊性、电梯安全的重要性;分析了政府主管部门、公众和媒体对电梯事故（故障）高度关注的原因;讨论了电梯安全与故障、可靠性的关系,电梯安全标准与安全、质量、运行性能的关系,以及电梯现行标准的性质;界定了安全标准与设计、制造规范的不同及关系;分析了行业及政府主管部门对公众普及电梯知识,客观、冷静地看待电梯故障与安全的重要性;说明了业内专业人员和政府主管部门应引导媒体和公众正确看待作为新型机电运输设备的电梯,认识不同档次电梯产品其质量和可靠性不同的必然性。     

ÖBB Steyrtalbrücke – Belastungsprobe und Langzeitmessungen

ÖBB Steyrtalbridge – Load test and long term measurements At km 65,621 of the railroad track between Linz and Selzthal the Steyrtalbridge was rebuilt in the years 2013 and 2014. The essential design criterion from the client ÖBB Infrastruktur AG was the endeavor of an optimized bridge under consideration of life‐cylce‐cost, which among other things despite a bridge length of 182 m can be designed without high‐maintenance breather switches. Based on the current standards and certain design flexibilities, which are allowed in the codes special ways and techniques were used to calculate the rail tension. With this results of the rail‐structure‐interaction it was possible to design without breather switches. As consequence of the assumptions in the planning process it was necessary to make comprehensive measurements which shall give information of the real behavior of the bridge and compare them with the assumptions and results of the static calculation. Therefor static and dynamic load test were performed before opening to regular traffic. In addition long term measurements were carried out to evaluate the load‐bearing behavior over time and to confirm the calculation approaches for the verification of the rail‐structure‐interaction. In this article the planning of the monitoringsystem, the implementation and results of the load test and the following long term measurements are illustrated.     

Evaluating effect of chloride attack and concrete cover on the probability of corrosion

Corrosion of reinforced concrete (RC) structures is one of the significant causes of deterioration of reinforced concrete (RC) structures. Chlorination is a major process governing the initiation and advancement of the injurious corrosion of steel bars. Now, several researches on the chlorination of concrete structures have been ongoing around the world. Present article reviews several recently performed chlorination studies, and from results of a field survey evaluates the effect of chloride content on the probability of corrosion and the influence of concrete compressive strength on the chloride content and penetration, also evaluates the effect of concrete cover over the chloride content of the RC structures at rebar depth and on the probability of corrosion.     

采空区隧道二衬受力特性模型试验与耦合分析

由于采空区地层的非连续特征,下穿隧道衬砌往往处在偏心受压的不利状态,后期运营病害相对严重。为了查清不同采空区条件下的衬砌结构受力特性,采用室内物理模型试验和基于连续-非连续耦合数值模拟相结合的方法,开展了相关研究。结果表明:(1)采空区的存在会使二衬结构受到偏压荷载,远离采空区侧总体受力大于近侧,且倾角越大偏压越严重;(2)采煤层厚度、冒落带与初支距离的增大会引起围岩压力的降低,二衬内力减小,安全性提升,当采煤层厚度大于1.8 m时或冒落带与初支间距大于0.8倍隧道洞跨后,采空区对二衬安全性的影响很小;(3)喷层厚度的增加阻碍了围岩变形,引起围岩压力增加,不利于二衬受力和安全性。研究结论对于完善采空区隧道围岩压力计算理论和支护结构设计方法具有理论指导意义。