Development of a double-sliding friction damper (DSFD)

Shen, Shaodong,Pan, Peng,Sun, Jiangbo,Gong, Runhua,Wang, Haishen,Li, Wei Techno-Press 2017 Smart Structures and Systems, An International Jou Vol.20 No.2

In practical engineering, the friction damper is a widely used energy dissipation device because of its large deformation capacity, stable energy dissipation capability, and cost effectiveness. While based on conventional friction dampers, the double-sliding friction damper (DSFD) being proposed is different in that it features two sliding friction forces, i.e., small and large sliding friction forces, rather than a single-sliding friction force of ordinary friction dampers. The DSFD starts to deform when the force sustained exceeds the small-sliding friction force, and stops deforming when the deformation reaches a certain value. If the force sustained exceeds the large sliding friction force, it continues to deform. Such a double-sliding behavior is expected to endow structures equipped with the DSFD better performance in both small and large earthquakes. The configuration and working mechanism of the DSFD is described and analyzed. Quasi-static loading tests and finite element analyses were conducted to investigate its hysteretic behavior. Finally, time history analysis of the single-degree-of-freedom (SDOF) and multi-degree-of-freedom (MDOF) systems were performed to investigate the seismic performance of DSFD-equipped structures. For the purpose of comparison, tests on systems equipped with conventional friction dampers were also performed. The proposed DSFD can be realized perfectly, and the DSFD-equipped structures provide better performances than those equipped with conventional friction dampers in terms of interstory drift and floor acceleration. In particular, for the MDOF system, the DSFD helps the structural system to have a uniform distributed interstory drift.

제작스프링와셔를 사용한 전단형 마찰댐퍼의 도입장력 영향에 관한 실험적 연구

박은수(Park Eun-Soo),최재혁(Choi Jae-Hyouk) 대한건축학회 2012 大韓建築學會論文集 : 構造系 Vol.28 No.8

Friction damper is a kind of passive energy absorbing device that controls displacement and vibration in order to improve the performance of building structures and numerous studies are under way about it. Now it is developed slightly different details of shear type friction dampers, but with the surface of friction materials and friction behavior of sliding friction surface to use the same concept in the history of the pressure exerted by the frictional resistance is determined. Thus, the size of pre-tensioned bolt that is introduced is a very important factor in determining the performance friction damper. Also, the time duration for the loosening of slip-proof bolts without sliding friction is also important and the plan prepared guarantees to determine the reliability of friction damper. In this paper, the flat washer that increase the friction force and the plate type spring washer which is special heat treatment that produced by friction used and a repeated static loading is test, and the coefficient of friction of friction damper, sliding strength, bolt tension maintenance ratio and energy absorption capacity of shear type friction damper was executed.

SUGGESTION OF MSTV (MODIFIED-STICK-TRANSITIONVELOCITY) MODEL FOR HYSTERETIC DAMPING MECHANISM

Wan-Suk Yoo,Gyung-Hun Nho,Bo-Sun Chung,Jae-Cheol Lyu 대한기계학회 2007 대한기계학회 춘추학술대회 Vol.2007 No.10

To decrease vibration and noise in washing machine, lubricated friction dampers were installed. Although the structure of the friction damper is simple, the dynamic behavior of the lubrication damper was not easy to develop a mathematical model. To see the dynamic behavior of a friction damper, physical tests were carried out via a material testing machine by changing exciting amplitudes and frequencies. Complicated curves of spring characteristics and damping showed a hysteretic behavior. In this paper, a reasonable model for a friction damper was suggested. To model the hysteretic behavior of a friction damper, a Coulomb friction model was first applied. To get a refined model for stick and transition, a STV (stick transition velocity) model was analyzed. To develop a more accurate mathematical model, a MSTV (modified stick transition velocity) model was proposed. In the MSTV model, the friction force could be changed due to the velocity of the damper, and the damping force was calculated according to the relative velocity between the external displacement and the deformation of the sponge in the friction damper. The MSTV model was in a good agreement to the experimental results.

Semi-active friction dampers for seismic control of structures

Kori, Jagadish G.,Jangid, R.S. Techno-Press 2008 Smart Structures and Systems, An International Jou Vol.4 No.4

Semi-active control systems have attracted a great deal of attention in recent years because these systems can operate on battery power alone, proving advantageous during seismic events when the main power source of the structure may likely fail. The behavior of semi-active devices is often highly non-linear and requires suitable and efficient control algorithm. This paper presents the comparative study and performance of variable semi-active friction dampers by using recently proposed predictive control law with direct output feedback. In this control law, the variable slip force of semi-active variable friction damper is kept slightly lower than the critical friction force, which allows the damper to remain in the slip state during an earthquake, resulting in improved energy dissipation capability. This control algorithm is able to produce a continuous and smooth slip forces for a variable friction damper. The numerical examples include a structure controlled with multiple variable semi-active friction dampers and with multiple passive friction dampers. A parameter, gain multiplier defined as the ratio of damper force to critical damper control force, is investigated under four different real earthquake ground motions, which plays an important role in the present control algorithm of the damper. The numerically evaluated optimum parametric value is considered for the analysis of the structure with dampers. The numerical results of the variable friction dampers show better performance over the passive dampers in reducing the seismic response of structures.

자동복원 마찰슬릿댐퍼의 해석적 거동특성 분석

이헌우,허종완 대한토목학회 2024 대한토목학회논문집 Vol.44 No.4

본 연구에서는 기존에 사용 및 연구되고 있는 자동복원 댐퍼, 마찰댐퍼, 강재댐퍼의 개념을 합쳐 자동복원 마찰슬릿댐퍼를 제안한다. 이를 위해 자동복원을 위한 초탄성 형상기억합금을 사용하고 마찰댐퍼와 슬릿댐퍼의 개념을 합친 혁신적인 댐퍼 구조를 고안하였다. 이후 이에 대한 상세설계를 진행하였으며 재료, 스트럿 폭, 볼트 체결력 등의 변수를 설정하였다. 총 12가지 댐퍼에 대해 ABAQUS 프로그램을 사용하여 모델링을 수행하고 설계된 로딩프로토콜을 대입하여 유한요소해석을 수행하였다. 결과적으로 초탄성 형상기억합금을 사용한 자동복원 마찰슬릿댐퍼는하중측면으로 우수하였지만 우수한 회복성능으로 에너지 소산능력은 크게 확보되지 않았다. 하지만 Gr.50 강재가 적용된 마찰슬릿댐퍼는 혁신적인 구조개선을 통해 하중, 에너지소산 등의 성능이 비약적으로 상승하였다. 이를 통해 마찰댐퍼와 강재댐퍼의 메커니즘이 합쳐진 댐퍼의 혁신적인 구조를 증명하였다. In this study, we propose a self-restoring friction slit damper by combining the concepts of self-restoring dampers, friction dampers, andsteel dampers that are currently used and researched. For this purpose, an innovative damper structure was designed using superelasticshape memory alloy for automatic recovery and combining the concepts of friction damper and slit damper. Afterwards, detailed designwas carried out and variables such as material, with of strut, and bolt fastening force were set. Modeling was performed using the ABAQUSprogram for a total of 12 dampers, and finite element analysis was performed by substituting the designed loading protocol. As a result,the self-recovering friction slit damper using superelastic shape memory alloy was excellent in terms of load, but the energy dissipationability was not significantly secured due to the excellent recovery performance. However, friction slit dampers made of Gr.50 steel havedramatically improved performance in terms of load and energy dissipation through innovative structural improvements. Through this,the innovative structure of the damper, which combines the mechanisms of a friction damper and a steel damper, was demonstrated.

Two-level control system of toggle braces having pipe damper and rotational friction damper

Ata Abdollahpour,Seyed Mehdi Zahrai 국제구조공학회 2023 Structural Engineering and Mechanics, An Int'l Jou Vol.86 No.6

This study examines the two-level behavior of the toggle brace damper within a steel frame having a yielding pipe damper and rotational friction damper. The proposed system has two kinds of fuse for energy dissipation in two stages. In this mechanism, rotational friction damper rather than hinged connection is used in toggle brace system, connected to a pipe damper with a limited gap. In order to create a gap, bolted connection with the slotted hole is used, such that first a specific movement of the rotational friction damper solely is engaged but with an increase in movement, the yielding damper is also involved. The performance of the system is such that at the beginning of loading the rotational friction damper, as the first fuse, absorbs energy and with increasing the input load and further movement of the frame, yielding damper as the second fuse, along with rotational friction damper would dissipate the input energy. The models created by ABAQUS are subjected to cyclic and seismic loading. Considering the results obtained, the flexibility of the hybrid two-level system is more comparable to the conventional toggle brace damper. Moreover, this system sustains longer lateral displacements. The energy dissipation of these two systems is modeled in multi-story frames in SAP2000 software and their performance is analyzed using time-history analysis. According to the results, permanent relocations of the roof in the two-level system, in comparison with toggle brace damper system in 2, 5, and 8-story building frames, in average, decrease by 15, 55, and 37% respectively. This amount in a 5-story building frame under the earthquakes with one-third scale decreases by 64%.

Experimental investigation on hysteretic behavior of rotational friction dampers with new friction materials

Majid Anoushehei,Farhad Daneshjoo,Shima Mahboubi,Sajjad Khazaeli 국제구조공학회 2017 Steel and Composite Structures, An International J Vol.24 No.2

Friction dampers are displacement dependent energy dissipation devices which dissipate earthquake energy through friction mechanism and widely used in improving the seismic behavior of new structures and rehabilitation of existing structures. In this paper, the cyclic behavior of a friction damper with different friction materials is investigated through experimental tests under cyclic loading. The damper is made of steel plates, friction pads, preloaded bolts and hard washers. The paper aims at investigating the hysteretic behavior of three friction materials under cyclic loading to be utilized in friction damper. The tested friction materials are: powder lining, super lining and metal lining. The experimental results are studied according to FEMA-356 acceptance criteria and the most appropriate friction material is selected by comparing all friction materials results.

SAFE댐퍼 보강골조의 구조성능 실험적 평가

소병찬,이창환,주영규,So, Byeong-Chan,Lee, Chang-Hwan,Ju, Young-Kyu 한국공간구조학회 2015 한국공간구조학회지 Vol.15 No.1

SAFE damper is a hybrid damper which is comprised of a friction damper and a metallic damper. These two dampers combine to resist external energy in stages. Under minor earthquake loads, the friction damper operates alone. However, the friction damper and metallic damper dissipate the energy together when a severe earthquake occurs. In comparison with other methods for seismic retrofitting, the SAFE damper has many advantages. The SAFE damper doesn't cause damage to facade of the building, and the construction period can be reduced when retrofitting. This paper describes experiments evaluating the structural performance of the SAFE damper. From the results, it was found that the structural performance of a conventional RC bare frame can be significantly improved by the installation of the SAFE damper.

SAFE댐퍼 보강골조의 구조성능 실험적 평가

소병찬,이창환,주영규 한국공간구조학회 2015 한국공간구조학회지 Vol.15 No.1

SAFE damper is a hybrid damper which is comprised of a friction damper and a metallic damper. These two dampers combine to resist external energy in stages. Under minor earthquake loads, the friction damper operates alone. However, the friction damper and metallic damper dissipate the energy together when a severe earthquake occurs. In comparison with other methods for seismic retrofitting, the SAFE damper has many advantages. The SAFE damper doesn’t cause damage to façade of the building, and the construction period can be reduced when retrofitting. This paper describes experiments evaluating the structural performance of the SAFE damper. From the results, it was found that the structural performance of a conventional RC bare frame can be significantly improved by the installation of the SAFE damper.

SAFE댐퍼 보강골조의 구조성능 실험적 평가

소병찬,이창환,주영규 한국공간구조학회 2015 한국공간구조학회지 Vol.15 No.1

SAFE damper is a hybrid damper which is comprised of a friction damper and a metallic damper. These two dampers combine to resist external energy in stages. Under minor earthquake loads, the friction damper operates alone. However, the friction damper and metallic damper dissipate the energy together when a severe earthquake occurs. In comparison with other methods for seismic retrofitting, the SAFE damper has many advantages. The SAFE damper doesn’t cause damage to façade of the building, and the construction period can be reduced when retrofitting. This paper describes experiments evaluating the structural performance of the SAFE damper. From the results, it was found that the structural performance of a conventional RC bare frame can be significantly improved by the installation of the SAFE damper.