In the design of many structures, a particular area of concern is exposure to seismic and windinduced vibrations. Simple viscoelastic dampers have been invented for use on the root attachments of turbomachine blades. Chang 5 viscoelastic materials are highly influenced by parameters like temperature. Implementation of abaquss viscoelasticity modeling in a.
Regarding the experiment, we report the results of an evaluation of seismic resistance against input in an. The sevenparameter fractional derivative model is modified with the temperaturefrequency equivalent principle and utilized to describe the dynamic properties. The viscoelastic materials generally used are copolymers or glassy substances. Influence of damping systems on building structures subject. Kelvinvoight model a spring and a viscous damper in parallel is commonly used to characterize dashpots at a single frequency. Furthermore, the optimal placement of dampers is sensitive to the nature of excitation force, total quantity of viscoelastic material used, and the modeling of veds. It is shown that the scheme of the optimal placement of veds provides more reduction in response compared with other schemes of placement of veds considered in the study. A novel viscoelastic damping treatment for honeycomb sandwich. Constrained layer dampers cld are in widespread use for passive vibration damping, in. Dynamic properties of structures with dampers modelled. It is the aim of this paper to compare the dynamic. The present paper concerns the development of a new rather inexpensive frictionviscoelastic damper and its application in a damping system for base isolation of a structure.
The seismic performance of viscoelastic dampers is greatly affected by viscoelastic materials. To examine the response reducing effectiveness of these dampers, it is necessary that engineers are able to conduct response analysis of structures installed with added dampers accurately and efficiently. A novel viscoelastic damping treatment for honeycomb sandwich structures. A material selected to exist in this region is ideally suited for such devices as isolators or tuned mass dampers because the modulus varies only slightly with changes in temperature and frequency.
In recent years, viscoelastic dampers veds have been widely used in. Samali graduate school of engineering, universi of technology, sydney, po box 123, broadway, nsw 2007. Structural dampers viscoelasticity mechanical engineering. Aug 20, 2014 in the design of many structures, a particular area of concern is exposure to seismic and windinduced vibrations. The solid viscoelastic dampers are among such passive energy dissipation systems. Pdf this paper concentrates on assessing how the variation of placement and number of dampers affect the structural responses of a building. Feb 02, 2014 we use your linkedin profile and activity data to personalize ads and to show you more relevant ads. Veds take advantage of shear deformation of viscoelastic materials vem. Evaluation of performance of viscoelastic dampers in. The viscoelastic dampers and damping parameters are tested and monitored by our inhouse test lab and independent test laboratories based on safety standard kta 3205. Francis shangrila place, mandaluyong city, philippines.
The fractional zener model is used to describe properties of the viscoelastic body while the friction damper is modelled by the coulomb friction law in a setvalued form. Design and implementation of tuned viscoelastic dampers. This research is an effort to develop an efficient method of design and easy implementation of tuned viscoelastic dampers tvds to control vibration in a milling process. Due to a horizontal ground excitation the viscoelastic plate is exposed to a shear loading. An installation scheme for viscoelastic dampers on bridge piers is proposed, and the mechanical models of the damper are analyzed according to the installation scheme. Energy dissipation properties of viscoelastic dampers are affected by frequency. To increase the effective damping force and to reduce the damper volume. Hybrid structural control using viscoelastic dampers and active control systems hybrid structural control using viscoelastic dampers and active control systems tzan, shyh. Also viscoelastic dampers are often used in base isolation systems, see e. Review on viscoelastic materials used in viscoelastic dampers. College of engineering, mathematics and physical sciences, university of exeter, exeter ex4 4qf, uk. This design and development process employs an analytical tvd model in combination with experimental dynamic model of a workpieceworkholding system, i. This paper investigates the seismic performance of posttensioned concrete piers with external viscoelastic dampers to improve the energy dissipation capacity of this type of structure. Pdf viscoelastic dampers utilize high damping from viscoelastic materials to dissipate energy through shear deformation.
Development of a viscoelastic tuned mass damper for floor. Vicodas viscoelastic dampers are designed in a way that they can be used in a wide. Optimal use of viscoelastic dampers in building frames for. I utterworth iie i n e m a n n 0141029695000348 engineering structures, vol. The properties of viscoelastic dampers, such as the possibility of energy. Pdf performance based placement of viscoelastic dampers in an. The present paper addresses the theoretical and experimental studies of the viscoelastic. As a consequence of the viscoelastic nature of rubbers, their dynamic behavior is significantly dependent on frequency, temperature and strain level. Hybrid structural control using viscoelastic dampers and. This paper is intended to introduce the results of the experiment and provide an overview of the product. They can be used in intake, exhaust, or mixed air applications. Influence of damping systems on building structures subject to seismic effects proceedings of the ninth international conference on civil and structural engineering computing, egmondaanzee, the netherlands, september 2003. Implementation of abaquss viscoelasticity modeling in a cartilage tissue simulation alexia stylianou 1. Hvac control dampers commercial control dampers are used in buildings to regulate the flow of air in an hvac system.
Modeling of a viscoelastic damper and its application in. Dynamic analysis of frames with viscoelastic dampers. Structural dampers free download as powerpoint presentation. Pdf frame structures with viscoelastic ve dampers mounted on them are considered in this paper.
Durg abstractan increase in the frequency of occurrence of natural disaster events like earthquakes has been evident over the past few years. Design and implementation of tuned viscoelastic dampers for. I created a model of a segment of cartilage tissue in abaqus. New installation scheme for viscoelastic dampers using cables. In the past, several rheological models were proposed for describing the dynamic behaviour of ve dampers and materials. Introduction damped outrigger concept to mitigate wind vibrations in tall buildings the st. The viscoelastic structural damper application can perform the timedomain and frequencydomain analyses for a typical viscoelastic damper. These dampers suppress bending and torsionmode blade vibrations, which are excited by unsteady aerodynamic forces during operation. Optimal vibration control of adjacent building structures. Viscoelastic damper, metallic damper, tuned mass damper and friction damper etc.
A novel viscoelastic damping treatment for honeycomb. Comparative study on the efficiency of friction and viscoelastic dampers. Comparative study of viscoelastic seismic damping systems. In the present paper, several dynamic properties tests of the viscoelastic damper at. Viscoelastic ve dampers have been successfully incorporated in a number of tall buildings as a viable energy dissipating system to suppress wind and. The evaluation of steel frame structures with viscoelastic. They have proven to reduce vibration and shock problems in electronics, appliances, automobiles and aircraft.
Pdf modeling of a viscoelastic damper and its application. Use of viscoelastic dampers in reducing wind and earthquake. The viscoelastic solid materials are used as a means to dissipate energy in viscoelastic dampers. Viscoelastic dampers are energy dissipation devices of passive type, frequently used to mitigate excessive vibration of structures due to winds or earthquakes. These tuned mass dampers are in general less costly than the more commonly used tmds employing viscous. There is no comparison between the results obtained for different models of dampers.
Passive energy dissipation devices, such as, viscous, viscoelastic, and friction devices are generally installed in buildings using diagonal or chevron braces. The damper properties are designed with reference from literature papers by m. This technology is widely spread in nuclear power since 80s of the last century, 1 and 2. In order to investigate and check the actual behavior of viscoelastic dampers installed at piping systems and subjected to severe earthquake motions, a shaking table test with fullscale piping and viscoelastic dampers was carried out. Modeling of viscoelastic dampers for structural applications. Mahmoodi, design and analysis of viscoelastic vibration dampers for structures, in proc. The preload is obtained by screws that compress the specimens by a quantity. Viscoelastic dampers are one of the most popular earthquake mitigation devices for building structures with a large number of applications in civil engineering.
Frontiers properties tests and mathematical modeling of. Viscoelastic damper has been long used in vibration control of structures. Damping, as a method to reduce unwanted vibrations, is most effective in cases where the vibratory system is excited with a frequency close to its natural frequency. Seismic response of structures with added viscoelastic dampers. Natural frequencies and modal damping ratios, required. Viscoelastic ve dampers are dependent on both relative velocity and displacement to dissipate energy. In the rubbery region, the material reaches a lower plateau in stiffness. There are two categories of control dampers commercial volume control dampers and balancing dampers. Damping dissipation viscoelastic dampers reduce vibrations by converting kinetic energy into heat thus damping the motion of the system. Relationship between viscous and viscoelastic dampers a common and effective way to reduce transient and steady state vibration is to add a layer of viscoelastic material, such as rubber, to an existing structure. The combined system often has a higher damping level and thus reduces the unwanted vibration inman 1996. Seismic behavior of posttensioned concrete bridge piers with. The typical viscoelastic damper consists of viscoelastic layers bonded with steel plates or solid thermoplastic rubber sheets sandwicthed between steel plates.
A procedure for the parametric identification of viscoelastic. Influence of damping systems on building structures. Modeling of a viscoelastic damper and its application in structural control article pdf available in plos one 126 june 2017 with 299 reads how we measure reads. The seismic response control of multistory frame structures using optimally placed viscoelastic dampers veds within consideration of soilstructure interaction ssi effect is investigated in this paper. Shaking table tests of a piping system with viscoelastic. Ve damping system in twin towers is a doublelayer shear damper using a 3m material, which is a. Development of a viscoelastic tuned mass damper for floor vibration applications, australian structural engineering conference, melbourne, vic.
Viscoelastic structural dampers have been implemented into structural layouts as a means to limit the strain and decrease the risk of failure in building components due to. Use of viscoelastic dampers in reducing wind and earthquakeinduced motion of building structures. See 3m data sheet for dynamic mechanical properties of isd 830 viscoelastic. The evaluation of steel frame structures with viscoelastic dampers. In particular, the effect of ve dampers model on the behaviour of a structure with dampers as a whole is. In this study a procedure for determining the optimum size and location of viscoelastic dampers is proposed using the eigenvalue assignment technique. Test procedure and determination of model parameters are also discussed. Viscoelastic structural dampers have been implemented into structural layouts as a means to limit the strain and decrease the risk of failure in building components due to such excitations. Therefore, the amount of normal strain of each specimen is. Biological tissues are primarily viscoelastic in nature, meaning that their mechanical behavior, i. The feasibility of using viscoelastic dampers to mitigate earthquakeinduced structural response is studied experimentally. Fluid viscous damper is composed of a piston head, a piston rod and a cylinder full of a viscous fluid. Theoretical and experimental study of viscoelastic damper.
These tuned mass dampers are in general less costly than the more. L for n viscoelastic dampers was put on the market by negurosu denko co. New installation scheme for viscoelastic dampers using cables hyunhoon choi and jinkoo kim abstract. Jun 01, 2017 modeling of a viscoelastic damper and its application in structural control article pdf available in plos one 126 june 2017 with 299 reads how we measure reads. The system is assumed to be elastic and responses of the system are obtained in frequency domain for stationary random seismic excitations. Optimal design of viscoelastic dampers in frame structures. The model parameters have physical meaning and they can be determined from simple timedomain and frequencydomain tests. Fluid viscous damper that operates according to the.
Pdf dynamic analysis of frames with viscoelastic dampers. A number of studies have been carried out to investigate the performance of viscoelastic dampers veds and magnetorheological dampers mrds in controlling the seismic response of buildings, but very few of them regarding the effect of. Reducing vibrations with viscoelastic structural dampers. In suppressing vibrations, these dampers reduce fatigue thereby prolonging blade lifetimes while reducing. Viscoelastic attributes of a realistic damper can be described by a combination of springs and ideal viscous dampers. Optimal design of viscoelastic dampers using eigenvalue. Dampers viscoelastic tuned mass dampers tmds use viscoelastic ve material as the suspension element, in such a way that the material exhibits the functionality of both the energy dissipation device viscous and the restoring device elastic. Viscoelastic tuned mass dampers tmds use viscoelastic ve material as the suspension element, in such a way that the material exhibits the functionality of both the energy dissipation device viscous and the restoring device elastic. Two viscoelastic specimens, parts 3 and 5, are cylinders mounted in parallel inside the preload device composed of parts 1, 2, 4 and 6, as shown in fig. This paper presents an analytical model for predicting the hysteretic behavior of viscoelastic dampers based on the boltzmanns superposition principle and the method of reduced variables.