D.G. Weng et.al (2012) in this paper, a simplified design procedure is proposed for seismic retrofit of earthquake-damaged frames with viscous dampers. Several key design steps were elaborated, including the estimation of the required equivalent damping ratio, the calculation of the expected damping force, the design modification the damping effect analysis, structural safety evaluation, and a comprehensive cost analysis. Following this simplified design procedure, viscous damping forces are first determined by storey shear forces and they are consequently optimized by storey drifts. A case study was presented to reveal the usefulness of the simplified design procedure. The results show that this simplified design procedure increase the design efficiency by reducing complex iterative computational analysis and yet with anenough accuracy for a practical design. Since the required damping ratio can be flexibly adjusted in a large range (i.e., 0~25%), though designing configuring viscous dampers, this simplified design method can not only meet current Chinese design codes but also satisfy different demands proposed by owners. The simplified method proposed in this paper is not only developed for the retrofit design of earthquake-damaged frame structures with viscous dampers, but also for the damping design of new building or existing buildings. To be specific, it can be used to improve structural dynamic behaviors of a building structure by modifying its damping.
Qasim Shaukat Khan, et.al (2013) This paper describes the outcome of an widespread study on the seismic performance of a structure with damper and with no damper below diverse earthquake acceleration frequency like, EQ Smonica, EQ Lucerne, EQ Pomona and EQ Yormo EQ Altadena. The paper pacts with the gradual process to carry out non-linear time history analysis of RC 2D frames. Efficiency of fluid viscous dampers also studied.
Four dissimilar accelerograms were utilized to examine the frames. Analysis was made for 2D framed structures and response of building is then studied. Decrease in building response is watched in terms of storey drift, base shear, acceleration, displacement.
Loredana E. Rosu, et. al (2013) the intend of this journal is analyzing a 13 story steel building judging 3 structural arrangements, to emphasize the the majority beneficial answer considering consumption of material and seismic performance. To examine the act of every structural arrangement and to conclude the most efficient solution, a usual steel structure is considered with three following structural systems: eccentrically braced system , Concentrically braced systems, and a system with viscous dampers.
Abdelouahab Ras et.al (2014) considered the result of fluid viscous dampers on moment resisting steel framed structure. Quick nonlinear analysis is carried out for Boumerdes earthquake data. Huge drop in shear forces, bending moments, acceleration, natural time period and displacements are examined. The inter storey drift nearly found to be zero which allow the block performance of structure and hence shear force decreased. Restoring energy of damper induces the visco elastic actions to damper and the damper becomes more efficient in energy dissipation.
Yuvraj Bisht & Saraswati Setia (2014) At some point in january 2001 Bhuj Earthquake in India, numerous multi-storeyed structures in city areas failed and experienced prevalent damages. Post-earthquake observations exposed several shortage in these structures as well as non-adoption of seismic engineering practices and lack of seismic resistant features. Efficiency of viscous dampers is studied on a five storey RC framed building. Dampers were situated at soft storey and NLTH analysis is implemented. With the use of viscous damper in the structure utmost reaction and drift decreases in structure through seismic loading. The performance of building structure in seismic loading is progressed to enormous level. By providing viscous dampers up to five stories, maximum drift is reduced from 3.7 % to 0.86 %. key factors for decrease of response of the structure are parameters related with Dampers and the dissipation of energy generated throughout earthquake by the mean of viscous Dampers. The maximum acceleration decreases from 2.2% to 0.4% and base shear raised from 0.8% to 1.67% by providing dampers.
Liya Mathew & C Prabha (2014) studied the outcome of dampers all along the width and height of multi storey RCC structures. A relative study is made among the bare frame and buildings fixed with viscous dampers. From the analysis it is found that fluid viscous dampers on the corners of all the four sides of a structure are efficient for Square plans regarding width. with regard to height the peak displacement and inter storey drifts are reduced more effectively when dampers fixed up-to three floors for rectangular plans. Velocity and displacements can be decreased efficiently by insertion of the dampers all through the height.
To learn the effect of FVD along the height, analysis was made on square plans of six and ten storeys. since the earlier section, it was bring to a close that, for the square plan case SQEC i.e., FVD on exterior corners was found to be the most useful. To realize the effect of FVD along the height, the above case was used for the supplementary study. The diverse cases that are taken into consideration to know the efficiency along the height are
ïƒ˜ FVD uniformly distributed
ïƒ˜ FVD on alternative floors
ïƒ˜ FVD on 1st three floors.
David Kim, et.al (2014) the estimation of seismic act and rate-efficiency of the several slim-type damper system is carried out in this study. A latest MSD system is developed for the vibration manage of seismic excited structures. The improved system need smaller installation spaces than conventional damping devices, while it can keep up satisfactory seismic performances. Three MSDs, namely, PSD, TSD and SSD, are created at a actual scale and loading tests are carried out. since the cyclic loading tests, dependable energy dissipation behavior is evidently watched. To legalize the realistic applicability, nonlinear time history analysis is executed for a ten-story earthquake excited building structure. The seismic presentation and cost-effectiveness of the MSD system are also examined according to the a variety of installation arrangements of the MSD system. From the relative results of numerical simulations and cost-effectiveness valuation, it is revealed that the MSD system is somewhat practicable and the combination of MSD systems can effectively progress the seismic performance of seismic excited building structures.
Afiya (2014) The Performance of the structure is studied in terms of time period, base shear, lateral displacements, storey drifts in linear static and linear dynamic analysis for with and without fluid viscous dampers building G+2, G+5 and G+10 storey models. The seismic analysis is carried out by response spectrum method and equivalent static method. The fundamental natural period of the structure enhances due to slighter stiffness of the bare frame structures compared to buildings having fluid viscous dampers.
The base shears because of seismic forces for the structure with fluid viscous dampers are more than the base shear acquired for without fluid viscous dampers. Compared to the usual structure with buildings having fluid viscous dampers the storey displacement reduces as the buildings having fluid viscous dampers. Addition of fluid viscous dampers in the structure will effect in severe reduction of lateral displacement of the building thus in order promises the protection of the structure. The storey drift increases in normal building as compared to building having fluid viscous dampers. The inter storey drift of both buildings i.e. bare frame building and building with fluid viscous dampers are within the limiting value i.e.0.004xh, where h is the storey height however adding up of fluid viscous dampers in the building severely decreases the inter storey drift when compared to that of building without fluid viscous dampers.
Vajreshwari Umachagi1, Katta Venkataramana2, G. R. Reddy3, Rajeev Verma4
in recent times Dampers have become more popular for vibration control of structures, because of their cost-effective, safe, and efficient design. This journal depicts a general idea of the performance of dampers on seismically affected structures. The review consists of different types of dampers like frictional dampers, viscoelastic dampers, metallic dampers, etc.
Yuvraj Bisht*, Saraswati Setia**
During january 2001 Bhuj Earthquake in India, many multi-storeyed buildings in urban areas collapsed and suffered wide spread damages. Post earthquake observations revealed many deficiencies in these structures including non-adoption of seismic engineering practices and lack of seismic resistant features. The seismic performance of a building can be improved by using energy absorbing devices, which may be active or passive in nature. Active control techniques have not found much appreciation due to its high cost and large instrumentation set up. Whereas, passive control systems such as base isolation, dampers, bracing systems etc are found to be easy to install and cost effective as compared to previous one. Use of dampers is now becoming cost effective solution to improve seismic performance of existing as well as new buildings. This paper deals with use of viscous dampers in the building. A five storey building with a open ground storey is analysed with and without braced type viscous dampers placed at soft storey. Non-linear time history analysis is carried out using SAP2000 software and comparisons are shown in a tabular and graphical format.
September-2015 Dhananjay A. Chikhalekar1, M. M. Murudi2
Abstract Earthquakes can make severe injure to structures. The structures previously built are susceptible to future earthquakes. The harm to structures causes deaths, injuries, financial loss, and loss of functions. Injure to the structure causes due to ground acceleration. This can be minimized by rising strength of the structure. Occasionally it is not feasible to boost the strength of the structure indefinitely. So it must be tried to enhance the ability of structure by means of seismic development methods. In this study, there are three different types of G+10 structures with fixed base, structure with high damping rubber bearing and structure with viscous damper are considered. These structures are modeled by finite element software SAP2000v16. These structures have identical plan area and are assumed to be situated in seismic zone IV and having medium soil condition. The study of these structures is made by response spectrum method and performance based pushover analysis method. The pushover analysis method is used to find out the performance point and capacity of structure. High damping rubber bearing isolators (HDRB) and viscous damper (VD) are use for seismic development of RC structure. The process of analysis implemented for fixed base structure is same repeated for structure with viscous damper (VD) and base isolated (HDRB) structure. So it will aid in comparative parametric study. The outcome of analysis are compared in terms of storey displacements, modal time period, storey acceleration, performance point, storey drift. The comparative study shows that storey displacement, storey acceleration, storey drift is reduced substantially for structure with high damping rubber bearing (base isolated structure).
Gulshan Bharti1 04, 2015
Abstractâ€” In recent years, substantial attention has been paid to research and development of structural control with the use of passive control devices. Fluid viscous dampers are in general well suitable to vibration control of civil engineering structures subjected to seismic excitations. The results of numerous studies on the effects of supplemental viscous damping on the response of structures have showed that they are efficient and very useful in mitigating the seismic energy. The fluid viscous dampers can be classified into linear fluid viscous dampers and nonlinear fluid viscous dampers. The nonlinear fluid viscous dampers are found more suitable than the linear fluid viscous dampers because nonlinear fluid viscous dampers have the ability of dropping peak damper force demand at big structural velocities at the same time as still offer adequate supplemental damping. The focus of this review paper is on the structural control of two parallel building structures coupled with nonlinear viscous damper. This paper comprises a concise chronological sketch of the progress in structural control with fluid viscous dampers. This paper also consists of a brief introduction regarding the nonlinear fluid viscous damper. The purposes of the current study on the nonlinear fluid viscous damper linking two parallel buildings are also taken in to account in this paper.
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