Fluid Viscous Dampers Research Articles

Theoretical and numerical study of the thermo-mechanical coupling effect on the fluid viscous damper

Theoretical and numerical study of the thermo-mechanical coupling effect on the fluid viscous damper

Review Paper on Seismic Analysis of Multi-Storied Reinforced Concrete Building with Fluid Viscous Dampers

Abstract: Frequent earthquakes around the world and the large number of buildings at risk have made it essential to focus on controlling how structures respond to these events. This demand has driven the increased use of structural response control methods globally. This study investigates the seismic performance of multi-storied Reinforced Concrete (RC) Buildings, distinguishing between Regular and Irregular Plan , with a focus on the role of Fluid Viscous Dampers (FVDs). The study aims to quantify the improvements in seismic resilience provided by these damping devices in mitigating the adverse effects of seismic events. Buildings having Regular and Irregular Plans are analyzed, with and without FVD using ETABS2018. The story responses in terms of Pseudo Spectral Accelerations, Maximum Displacement, Story Drift and Story Shear have been compared. The results of the Time History Analysis represent the effectiveness of dampers in improving the structural response and the damping demand on structural systems

Analysis of G+20 Horizontally Connected Buildings with and Without Fluid Viscous Dampers

As urban populations continue to grow globally, the demand for new cities and high-rise structures is increasing due to limited land resources and expanding social and commercial activities. To address these challenges, this study investigates the seismic performance of G+20 horizontally connected buildings, focusing on the effects of fluid viscous dampers (FVDs) on structural response. A 3D model of two G+20 buildings, one with and one without FVDs, was developed using ETABS software, and seismic analysis was conducted for a Zone V seismic region in India. The study evaluates key performance parameters, including storey displacement, storey drift, and storey shear, to assess the effectiveness of the dampers. Results showed that adding FVDs significantly reduced overall building displacement, particularly in the X-direction at the top storey, with a reduction of approximately 40%. The Y-direction saw a more modest 5% reduction, attributed to geometric and stiffness irregularities. Additionally, storey drifts in the X-direction were higher than in the Y-direction but were significantly reduced after installing dampers. The findings highlight the importance of FVDs in improving the seismic resilience of horizontally connected high-rise buildings and offer valuable insights for future structural design in earthquake prone areas.

Far-field earthquake response examination of RC buildings equipped with fluid viscous dampers

Far-field earthquake response examination of RC buildings equipped with fluid viscous dampers

NUMERICAL ERROR METHOD TO DETERMINE THE EFFICIENCY OF REDUCING VIBRATIONS DUE TO EARTHQUAKE LOADS ON BUILDINGS USING FLUID VISCOUS DAMPER

According to The Indonesian Earthquake Map, Padang City in West Sumatra is in Earthquake zone 6. This indicates that Padang City is very vulnerable to earthquakes. Meanwhile, developments in the construction of high buildings also continue to show progress all the time. The main problem that is often faced is the issue of structural damage due to earthquakes. Efforts are needed in earthquake engineering on buildings so that collapse can be minimized. The earthquake damping system used is FVD (Fluid Viscous Dampers) with different types. The Type-A damper is FVD-750 kN and the Type-B damper is FVD-1000 kN, and without using a damper. This research aims to analyze the efficiency of reducing earthquake loads such as floor displacement and vibration period of an 18-story building structure 18 meters high from the base.The analysis method used is a numerical method by calculating earthquake load reduction based on numerical error analysis from the two types of dampers used on structures without using dampers. Building planning refers to SNI 1727-2013, SNI 1726-2019, and SNI 2847-2019, and is assisted by ETABS software. Based on SNI 1726-2019, earthquake risk category II, soft soil condition type (SE), earthquake acceleration response value SDS = 0.745g and SD1 = 0.784g are obtained. The earthquake load used is a dynamic load, taking into account that the condition of the building is irregular. Based on the results of the analysis, it was found that the displacement between floors using the Type-AFVD Damper could reduce the displacement by up to 45.72% and with the Type-B FVD Damper it could reduce the displacement by up to 92.72%. Meanwhile, the period of vibration natural using a Type-A FVD Damper can be reduced by up to 12.34% and using a Type-B FVD Damper can be reduced by up to 33.21%.

Uplift derailment for near-fault high speed train-track-hybrid control cable-stayed bridge system

Seismic uplift of a high-speed rail (HSR) cable-stayed bridge’s bearing affects train safety. Existing technique lacks improved seismic isolation in the vertical direction due to the bearing’s vertical stiffness. Based on the on-site dynamic test and train derailment table experiments and different software, the train running safety of the semi-floating system of the cable-stayed bridge-rail-train system was analyzed using different damping and isolation control strategies. The larger vertical seismic component increases the danger of flange climb derailment when subjected to near-fault earthquakes. After installing lateral/or viscous fluid dampers (VFDs) and magnetorheological (MR) bearing (A = 3.0), the bridge has an obvious bearing uplift response. Still, it is not enough to threaten the structure, and the seismic damping capacity of the bridge structure is improved, making the train ride safe. This research presents discoveries on the impact of bearing uplift on train operational safety. Specifically, it reveals that the lifting of the end bearings on both sides of the main girder is not synchronized. This investigation presents a technical reference for comparable initiatives.

Modeling and parametric research of a bellows-type fluid viscous damper with annular damping gap for spacecraft micro-vibration suppression

Modeling and parametric research of a bellows-type fluid viscous damper with annular damping gap for spacecraft micro-vibration suppression

Seismic response of SMRFs retrofitted with bracing systems and nonlinear fluid viscous dampers under near and far field ground motion

Seismic response of SMRFs retrofitted with bracing systems and nonlinear fluid viscous dampers under near and far field ground motion

Experimental study on fatigue damage mitigation in welded beam-to-column connections with passive vibration control

To investigate the effectiveness of a viscous fluid damper (VFD) in mitigating fatigue damage in welded beam-to-column connections, six specimens were manufactured with the full penetration groove weld process. These specimens were divided into three groups: S1, S2, and S3, each containing two specimens. One specimen in each group was equipped with VFD, while the other was not. All specimens underwent the same elastic cyclic loading stage, but a different plastic cyclic loading stage for each group. The study results indicate that the presence of VFD can significantly enhance the load-bearing capacity of the welded beam-to-column connection by 10%–15% when subjected to the same displacement amplitude at the beam end. The primary cause of failure in the welded beam-to-column connection is the fatigue damage of the weld toe on the beam flange, which requires more attention during the welding process. Additionally, the VFD can effectively reduce stress concentration at the weld seam area, leading to a maximum of 50% decrease in the maximum stress near the weld toe of the beam flange center, as observed in our study.

Fluid viscous dampers in tackle-damper configuration: An experimental study

This study presents dynamic test results on a recently developed damper placement known as the tackle-damper configuration. This innovative setup integrates a viscous damper alongside two inclined tackles, each comprising multiple turns of wire ropes threaded between upper and lower sheaves. This configuration has the ability to amplify damper deformations and forces based on the mechanical advantage of the tackle. Four specimens of tackle-damper configurations are tested under different dynamic harmonic and seismic loadings. Obtained results indicated that tackle-damper configuration changes pure viscous behaviour of the fluid viscous damper to an amplified viscoelastic behaviour. It is verified that energy dissipation in the tackle-damper configuration arises from two sources, i.e. fluid viscous damper and capstan friction between the wire ropes and the sheaves. Ideally, deformation and force amplification factors in the tackle-damper configuration should depend solely on the number of wire ropes and the inclination angle of the tackle. However, it has been found that true force amplification factor is much larger than the ideal value due to the capstan friction. Moreover, true deformation amplification factor can also be much smaller than the ideal value. This is attributed to the elastic stretching of individual wire ropes within the tackles. Therefore, both friction and wire rope elongation substantially affect the true amplification capabilities of the tackle-damper configuration.

Unlocking Resilience: Examining the Influence of Fluid Viscous Dampers on Seismic Performance of Reinforced-concrete Structures in Earthquake-prone Regions

Unlocking Resilience: Examining the Influence of Fluid Viscous Dampers on Seismic Performance of Reinforced-concrete Structures in Earthquake-prone Regions

Seismic Study of An Isolated Cable-Stayed Bridge under Near-Fault Ground Motions

During strong earthquakes, pounding may occur on large-span bridges and their approach bridges. The effect and mitigation measures of such pounding have rarely been explored in previous studies. This paper primarily uses finite element models to investigate the pounding effects at the expansion joints between the main cable-stayed bridge and its approach bridge. Friction pendulum bearings (FPBs) and fluid viscous dampers (FVDs) are used to alleviate poundings. Furthermore, a detailed analysis is conducted on how the pounding effect of the isolated main bridge with FPBs and FVDs is affected by the wave passage effect, ground motion type, and soil type. This study reveals that FPBs and FVDs can effectively reduce pounding effects and the associated risks. Even with the installation of FPBs and FVDs, lower seismic wave velocities and near-fault seismic motions with pulse effects can significantly increase the pounding effects between the cable-stayed bridge and its approach bridge.

SINGLE-DEGREE-OF-FREEDOM VIBRATION ISOLATION SYSTEM WITH ONE ADDITIONAL SUPPORT

Vibration isolation is one of the most effective methods for reducing vibration levels of supporting structures when installing vibroactive equipment (active vibration isolation) or vibration levels of vibro-sensitive objects relative to foundation vibration levels (passive vibration isolation). Damping devices utilizing high-speed fluid flow through apertures have found wide applications in shock vibration isolation and vibration isolation systems in aerospace and defense sectors. Recent research has led to the development of viscous fluid dampers (VFDs) for use in civil engineering, particularly in earthquake-prone areas. Scientists conducted experiments aimed at determining the ability of viscous fluid dampers to reduce damages and displacements of structures without increasing stresses. Mathematical models have been developed and are applied in vibration isolation systems. When vibroactive equipment is installed on building and structure support systems, vibrations with sufficiently high vibration parameters may occur, potentially leading to loss of load-bearing capacity. In such cases, vibration isolation is considered one of the most effective methods for reducing these vibration levels. In this study, a calculation method has been developed, and calculation dependencies and algorithms for calculating vibration protection systems with nonlinear characteristics (additional support connections, viscous fluid damper) have been derived for both single-degree-of-freedom and two-degree-of-freedom systems. The research involved an analysis of normative and scientific-technical literature on the subject: types, structural solutions, calculation, and analysis of vibration protection systems. The main method selected was based on the use of transfer functions of linear systems (the non-traditional "normal form" method). Calculations were performed using computer mathematics systems- Matlab.

Enhancing longitudinal performance in railway suspension bridges through an integrated cable restrainer system

Longitudinal motion is a crucial factor affecting the fatigue life of expansion joints, bearings, dampers and short suspenders in suspension bridges. Traditional control methods relying solely on fluid viscous dampers often magnify the relative displacement between the main cable and the girder (hereafter referred to as relative displacement), leading to fatigue problems in the short suspenders. To overcome these shortcomings, an Integrated Cable Restrainer System is proposed. Firstly, a suspension bridge is described, and both a Refined Finite Element Model (RFEM) and a Simplified Finite Element Model (SFEM) are developed and compared. Subsequently, the effectiveness of three cable measures in reducing the longitudinal motion response and the relative displacement of the bridge is evaluated: the cable central buckle (Type I, connecting the main cable and the girder), the inclined control cable (Type II, controlling the main cable) and the longitudinal control cable (Type III, controlling the girder). Finally, an Integrated Cable Restrainer System integrating type I to type III measures is proposed and compared with FVDs, and its control benefits on train and seismic induced vibration are discussed. The results indicate that the SFEM has a higher calculation efficiency while maintaining comparable accuracy. All three types of cable restrainers are effective in controlling the longitudinal movement of the girder end, although type III increases the relative displacement. The Integrated Cable Restrainer System not only effectively controls longitudinal motion (induced by trains and seismic events) but also reduces the relative displacement at the short suspender positions. By employing the Integrated Cable Restrainer System combined with dampers for controlling longitudinal motion, the undesirable effects associated with damper usage can be effectively mitigated. This research serves as a valuable reference for bridge design and longitudinal motion control in suspension bridges. Data AvailabilitySome or all data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.

Girder quasi-static cumulative displacement-based suspension bridge nonlinear damper leakage diagnosis by eliminating stochastic traffic effects

Fluid viscous dampers (FVDs) are the key energy dissipation devices for long-span suspension bridges, and their leakage poses a threat to the stable and reliable operation of bridge restraint systems. Therefore, this paper proposed an FVD fluid leakage diagnosis method based on girder longitudinal displacement monitoring data. First, the longitudinal vibration equation of the main girder under traffic loads was derived to reveal the displacement characteristic of girder-end motion. On this basis, considering that different displacement components under traffic loads are coupled and transient analysis directly utilizing traffic loads as the excitation is complicated and inefficient, an analysis framework focusing on the influence mechanism of FVD leakage on quasi-static displacement was established. Second, an equivalent mechanical model for simulating the hysteresis relationship of leaked FVD was proposed and verified. Then, the influence of variations in the location, number, leakage level and parameters of the leaked FVD on the quasi-static displacement was studied. Third, the equivalent traffic load (ETL) indicator was constructed to characterize the traffic volume. Furthermore, a quasi-static cumulative displacement and ETL correlation model, which can effectively eliminate the interference of traffic flow variations, was proposed for the leakage diagnosis of FVD. Finally, the proposed method was verified by real suspension bridge monitoring data. The results demonstrated that the proposed method can effectively detect a mild increase in the girder-end cumulative displacement due to FVD fluid leakage.

Study on the overturning resistance of a new staggered story isolated structure

The isolated bearings of high-rise base isolated structures are prone to buckling instability under tensile and compressive stresses, leading to structural overturning. This limits the height of base isolated structures, while a new staggered story isolated structure is suitable for high-rise isolated buildings. Its overall structure resembles the "mortise and tenon" commonly used in traditional Chinese architecture. On one hand, the core tube is embedded in the substructure, which lowers the center of gravity of the superstructure and reduces the overturning moment. On the other hand, the interlocking of the superstructure and substructure provides advantages for the overturning resistance of the structures. In this study, a calculation formula was derived for the overturning resistance ratio of the new staggered story isolated structure. Five models with a height of 106.4 m were established using ETABS. The effects of changing the position of the frame isolated layer and adding viscous fluid dampers on the overturning resistance were analyzed. The results indicate that the new staggered story isolated structure has a lower risk of overturning compared to both the non-isolated structure and the base isolated structure under rare earthquakes. It effectively mitigates excessive tensile stress on the isolated bearings and minimizes the number of isolated bearings experiencing tensile stress. Additionally, it reduces the risk of overturning of the superstructure in high-rise buildings under rare earthquakes, thus compensating for the height limitations of base isolated buildings. As the position of the frame isolated layer in the new staggered story isolated structure is raised, the overturning resistance ratio of the superstructure increases while that of the substructure decreases. Therefore, it is necessary to reinforce the substructure. Placing viscous fluid dampers between the substructure and the core tube can enhance the overturning resistance ratio of the substructure and the overall structure. The new staggered story isolated structure effectively reduces the number of plastic hinges in the superstructure and minimizes damage to the core tube between the frame and the core tube isolated layers. Moreover, the addition of viscous fluid dampers makes the hysteresis curves of corner column isolated bearings in the frame isolated layer fuller.

Research on seismic response of museum cultural relics for shock absorption and seismic isolation

Museum cultural relics are valuable heritages of the development and change of the Chinese Nation over thousands of years, so the research on the protection of cultural relics is of great significance. In this paper, for the research on double shockproof of museums and cultural relics showcases in the museum, finite element models of the base fixed structure, base isolated structure and viscous fluid damper structure of the museum are established, modal analysis and time-history analysis are carried out to compare the seismic effect of the three kinds of structures. At the same time, the fixed cultural relics showcase, isolated cultural relics showcase and viscous fluid damper cultural relics showcase are established, and the seismic response analysis is carried out by inputting seismic waves and floor waves of the museums to study the acceleration and displacement response of the showcase countertop. The results show that, compared with the base fixed structure and base isolated structure of the museum, the viscous fluid damper structure of the museum can better reduce the inter-story shear force, inter-story drift and the floor acceleration response of the structure, and more effectively consume the seismic energy input to the structure, with the most obvious effect of shock absorption and seismic isolation; relative to the base fixed structure and base isolated structure, under the action of floor waves of the viscous fluid damper structure of the museum, the isolated cultural relics showcase and viscous fluid damper cultural relics showcase for shock absorption and seismic isolation are very obvious, so the isolated cultural relics showcase and viscous fluid damper cultural relics showcase are placed in the viscous fluid damper structure of the museum, all can achieve the purpose of the double shockproof of the cultural relics.

An investigation for enhancing seismic performance of high-rise buildings using fluid viscous damper (FVD)

An investigation for enhancing seismic performance of high-rise buildings using fluid viscous damper (FVD)

Blast mitigation of elevated water tanks equipped with resilient fluid viscous dampers

Blast mitigation of elevated water tanks equipped with resilient fluid viscous dampers

Coastal bridges with a box-girder superstructure under the action of solitary waves: Study on the optimization of bearings, dynamic characteristics and failure mechanism

Coastal bridges featuring a box-girder design are instrumental in advancing coastal transport and economic development. However, numerous coastal bridges with limited clearance above sea level are prone to the impact of the extreme waves. In order to enhance the survivability of superstructures of the bridge in the face of severe wave conditions, the present study implemented measures such as adding steel fasteners to conventional laminated rubber bearings and incorporating fluid viscous dampers to the box-girder superstructure. A three-dimensional fluid-structure coupling model, including a three-dimensional numerical flume, adjacent structures, and a box-girder superstructure supported by various bearings, is developed to explore the failure mechanisms and dynamic properties of the superstructure when subjected to extreme solitary wave conditions. Then, the effects of the implemented measures on the disaster resistance of bridge superstructures are comprehensively examined. The results indicate that: (1) After subjected to extreme solitary wave actions, the box-girder superstructure is at a high risk of failure due to sliding, unseating, and overturning. (2) Adding steel fasteners to conventional laminated rubber bearings can effectively alleviate overturning failure of the box-girder superstructure. (3) The addition of fluid viscous dampers into the box-girder superstructure can effectively decrease its maximum displacement. (4) Bridges with box-girder superstructures typically undergo bearing vertical and deformation failure during their failure process.