Bellows Expansion Joints

2021 ◽  
pp. 175-180
Author(s):  
Charles Becht

Prior to 1988, coverage of metallic bellows expansion joints in ASME B31.3 was very limited. Bellows were required to be designed in accordance with the rules for pressure design of unlisted components (par. 304.7.2) and the Standards of the Expansion Joint Manufacturers Association, Inc. (EJMA Standards). Appendix X was added in 1988, and has undergone several significant revisions in subsequent years. It provides specific Code coverage for metallic bellows expansion joints by adopting, with exceptions and additions, a widely used industry standard for expansion joints, the EJMA Standards.

Author(s):  
Pengzhen Lu ◽  
Chenhao Zhou ◽  
Simin Huang ◽  
Yang Shen ◽  
Yilong Pan

Expansion joints are a weak and fragile part of bridge superstructure. The damage or failure of the expansion joint will lead to the decline of bridge durability and endanger the bridge structure and traffic safety. To improve the service life and performance of bridge expansion joints, the ideal method is to use seamless expansion joints. In this study, starting from the commonly used asphalt mixture gradation of seamless expansion joint, and taking into account the actual situation of bridge expansion joint structure and environment in China, the gradation and asphalt-aggregate ratio are preliminarily designed. Through a Marshall test, the corresponding asphalt mixture is evaluated and analyzed according to the stability, flow value, and void ratio, and the optimal gradation and asphalt-aggregate ratio are determined. Finally, the asphalt mixture is prepared with the mixture ratio design, and the test results of an immersion Marshall test, fatigue performance test, and full-scale test verify that the asphalt mixture meets the road performance requirements of seamless expansion joints. On the basis of the experimental data, the performance of large sample asphalt mixture is continuously tested, compared, and optimized. The results show that the asphalt mixture ratio designed is true and reliable, which can provide reference for the optimal design of seamless expansion joint filler.


Materials ◽  
2020 ◽  
Vol 13 (12) ◽  
pp. 2842
Author(s):  
Janusz Bohatkiewicz ◽  
Michał Jukowski ◽  
Maciej Hałucha ◽  
Marcin Dębiński

The noise generated at the interface between the wheels of vehicles and the road surface is well recognized in the literature worldwide. Many publications describe the phenomenon of reducing this kind of impact by silent road surfaces. A specific type of this noise is the sound generated by vehicles passing over the expansion joints of bridge structures. Due to the impulsive nature of this sound, it is very onerous for people living in the close vicinity of bridge structures. The passage of vehicles over expansion joints causes the formation of vibrations that are transmitted to the structural elements of bridge structures, which may cause the formation of the material sounds (especially arduous in the case of bridges with steel elements). An attempt to reduce this impact was made by making a prototype acoustic cover of the expansion joint on the selected bridge. The paper presents the results of research on the “in situ” acoustic effectiveness of this cover. Additionally, the noise was modelled in the object surroundings before and after the cover’s application. The acoustic efficiency of the cover in the whole measured frequency range was 5.3 dBA. In the narrower frequency bands (1/3 octave bands), larger sound level reductions were observed. The maximum sound levels measured under the tested dilatation were less than 10.0 dBA lower than the maximum sound levels measured under the reference dilatation.


2011 ◽  
Vol 109 ◽  
pp. 420-423
Author(s):  
Yan Kai Fang

Expansion joints are non-standard devices whose shape and parameters could vary with temperature, pressure, displacement and cycle life, so it's drawing work is very burdensome. Expansion joint industry is badly in need a set of accurate, reliable and stong practical professional graphics software. Therefore this paper carried out targeted secondary development of the software on the basis of digestion and absorption of SolidWorks2010 so as to meet the urgent needs of expansion joints industry. The structure of most parts of bellows expansion joints is not complex, and their geometry are relatively simple and fixed, so it is very suitable for parametric modeling method.


Author(s):  
Misa Jocic

There have been various attempts to deal with the optimization of solutions which involve expansion joints in piping systems where sufficient flexibility can’t be found using suitable pipe routing. The difficulty of piping designs which involve expansion joints is that they rely upon two engineering expertises: Pipe Flexibility and Stress Analysis on one side and Expansion Joint Design and Construction on the other. Arguably distinctively different, they have been looked upon as totally detached engineering disciplines and it is rarely that companies have two of these experts residing under the same roof. Pipe Stress Engineers basically relied on support form Expansion Joint Experts on “as required basis” and called upon their knowledge only when needed. Thus, we have the situation where knowledge related to the design and construction of expansion joints sits with expansion joints manufacturing companies, which are totally separate and often remote entities in the piping design process. Even so, the ever present demand for techno-economical optimizations, points us to the following observations. The “Traditional method”, where Pipe Stress Engineer defines on his own the requirements for expansion joints and describes them in the technical specification for purchasing is, or should be, a theme of the past. This approach may be used only as a first attempt in search for the solution, but given that it never heads in the direction of achieving optimal techno-economical results, needs to be upgraded with additional steps.


Author(s):  
Sanjay Kaul ◽  
Rajpalsinh Gohil ◽  
Parul Bisharia ◽  
Apoorva Roy

Abstract The CCR (Continuous Catalytic Reforming) Platforming™ process is Honeywell UOP’s technology to convert low octane naphtha to high octane fuel or petrochemical feedstock such as aromatics. It is accomplished in a hydrogen atmosphere at elevated temperature and pressure across a platinum containing catalyst. The process flow is routed through heaters, blowers and coolers between reactors to maintain the heat of reaction. This article captures the procedure of selecting a suitable expansion joint for absorbing thermal movement between two important pieces of CCR equipment — the regeneration cooler and regeneration blower. It shows the design calculations of a universal hinged expansion joint operating at 0.14 MPa and 593°C in a pipe of 762mm diameter. The joint contains 5 single-ply INCOLOY 800H bellows with unreinforced convolutions. Design calculations of the expansion joint have been carried out using formulae prescribed in the Expansion Joints Manufacturers Association (EJMA) standard. Since it is difficult to quantify stresses using a movement test, the EJMA calculations have been verified against finite element analysis results of the bellows.


2014 ◽  
Vol 592-594 ◽  
pp. 1539-1543
Author(s):  
C.S. Pargaonkar ◽  
Maneesh Batrani

The rapidly growing trend for higher capacity steam turbines with large steam flows demand the use of long lengths and large size pipes. Thermal expansions of up-to 50mm and pipe diameters up-to 2600mm are required to be dealt with calling for the use of Expansion Joints to control the stresses in both the pipes as well as the end equipment. The bellows in the Expansion Joints used for the steam turbine application are stretched to their limiting values of the stresses in order to make them as flexible as possible with the aim of limiting the pipe and end equipment operational stresses. Three fundamental types of loading are presented to provide insight into the way bellows convolutions are stressed during operation. The optimization of the bellows profile geometry is discussed briefly. A comparison of the resulsts obtainied by proven computational methods as well as by using international EJMA standard is made to highlight the safety built in the well established methods used.


2013 ◽  
Vol 135 (5) ◽  
Author(s):  
José Carlos Veiga ◽  
Nelson Kavanagh ◽  
Ana Maria F. Sousa ◽  
Jorivaldo Medeiros ◽  
Jordana Luiza Veiga

This paper proposes a method to estimate the actual reaction loads in gimbal and hinged metal bellows expansion joints. Friction and some media pressure forces, which are not considered in current Expansion Joint Manufactures Association (EJMA) standard calculations, are added to bellows spring rate to estimate the expansion joint movement reaction moment. The proposed calculation method is based upon pressure and movement tests of large size expansion joints.


Author(s):  
Niculin Meng ◽  
Simon Hoffmann

Bridge expansion joints are key structural components that are subjected to very demanding dynamic loading. Even though modern expansion joints are being continuously developed and improved, they are generally still much less robust and less durable than the main structure. Therefore, replacement of expansion joints is commonly required in the maintenance of our transportation infrastructure. In carrying out such replacement work, the impacts on traffic and on the bridge’s superstructure should be minimised, for economic and sustainability reasons. This paper presents various expansion joint replacement methods which minimise such impacts, for a wide range of scenarios and movement requirements. The methods described cover single gap joints, sliding finger joints and modular joints – which, where appropriate, retain and use elements of suitably designed existing joints, thus optimising the replacement process in various respects.


Author(s):  
Jørgen Højris Jensen

<p>An appropriate design and correct installation of expansion joints are key crucial for the costs and the life span of the entire structure. As no joint types have a life expectancy similar to the life span of the structure (100-120 years), focus needs to be on choosing joint types with minimal maintenance costs combined with the lowest number of and simplest solution for exchange.<p> Many considerations must be taken when choosing types of expansion joints for a new or existing bridge. Most importantly, the functional requirements like movement capacity, traffic volume and type, noise emission etc. must be observed.<p> The details of the joint type and the details of the bridge area around the expansion joints are important as well considering maintenance costs and ultimately the life span of the bridge.<p> Cases with the most common types of expansion joints are used to look at challenges with life span, maintenance, observation of faults and leaks and consequential damages.<p> New editions of flexible plug joints including new basic materials have reached market in the last couple of years. Instead of the traditional bituminous materials the new expansion joint is ETA approved based on polyurethane. Basic material characteristics are described alongside the detailed geometry and installation options. Material requirements in the ETAG 032-3 Flexible Plug Joints are also described.<p> In November 2017 new general work descriptions for flexible plug joints were published. Requirements and expectations for life span are discussed. Furthermore, the first experiences with the incorporation of polymeric plug joints are evaluated focusing on projecting and execution related challenges.


Author(s):  
Vasily Prusakov ◽  
Marina Gravit ◽  
Andrey Pekhotikov ◽  
Vladimir Pavlov

Правильное проектирование, устройство и монтаж деформационных швов дают возможность обеспечить длительный срок службы основных несущих и ограждающих конструкций зданий, а также элементов внутренней и внешней отделки. Огнестойкие заполнения устанавливают для компенсации возможных изменений ширины шва от первоначальной ширины в горизонтальные и вертикальные деформационные швы монолитных и сборных железобетонных конструкций зданий и сооружений различного назначения, а также в зазоры между торцом вертикальных стен и межэтажных перекрытий. Для защиты деформационных швов в конструкциях зданий и сооружений от воздействия пожара применяются огнестойкие заделки. В европейских нормативных документах такие противопожарные барьеры специально разрабатываются для применения в деформационных швах и работают при сжатии, растяжении и сдвиге шва. В России изделия и материалы, выполняющие функцию противопожарного барьера, не испытываются в условиях знакопеременной нагрузки. В статье приведена методика испытаний на огнестойкость для деформационного шва в железобетонной конструкции. Получены результаты по параметрам целостности и теплоизолирующей способности для железобетонных плит с последующим в сторону увеличения ширины зазора между плитами и сдвига их относительно друг друга на +25 % составляет не менее 245 мин.Buildings and structures of complex architectural forms and large extent are subject to deformations under the influence of fluctuations in the temperature of the outside air, uneven sedimentation of the soil base, seismic phenomena and other causes. To prevent cracks in bearing and fencing structures, expansion joints are provided that cut the building into compartments. Proper design, construction and execution of expansion joints are of great importance in construction, as they provide the opportunity to provide long service life and fire resistance of the main load-bearing and enclosing structures of buildings, internal and external finishes. Normative requirements for the device and technical parameters of fire protection of expansion joints do not currently exist, and since the expansion joints are elements of load-bearing and enclosing structures, their fire resistance is determined in conjunction with the rest of the elements of fire protection barriers, use and application is regulated by the norms of Russian federal legislation. To increase the overall fire resistance of the construction, special fire barriers are used, which are installed inside the expansion joints. The article presents an overview of the fire barriers of expansion joints of both foreign and domestic producers. It is shown that for the protection of expansion joints in a fire, fire barriers are used, specially designed for use in expansion joints, which are guaranteed to work with compression, stretching and shear. It has been established that the production of innovative fire-retardant materials is one of the main tasks of fire safety. This is also the way of the consistent transformation of the idea into a product that passes through the stages of research, design development, production and realization in civil and industrial buildings. It is necessary to choose a comprehensive solution that ensures the maximum satisfaction of the requirements when performing fire protection work to protect the expansion joint when exposed to a fire. The authors declare that the structures (products) intended for fire protection of the expansion joint should provide a stable own mechanical tensile strength of at least 40%; at least 50% compression; for a shift of not less than 20%, the retention of elastic properties at the manufacturer’s declared maximum tensile-compressive stress per product of not less than 100 cycles. After the test, the structure (article) should not have mechanical damages and deformation of the filler, as well as the manufacturer’s declared fire resistance tested with at least 20% expansion from the design width of the expansion joint. When using other fillers for the fire barrier, it is recommended that the above requirements should be met using material that provides deformation characteristics, both in the compression of the joint and during its stretching, and in the shear, during the entire period of the intended use. Particular attention should be paid to the technology of interfacing the structures (products) of fire barriers when they are installed in expansion joints along the entire length, which is guaranteed to prevent the appearance of technological gaps and voids.


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