The document discusses vibration control systems for structures and summarizes a presentation on the Yokohama Land Mark Tower in Japan. It describes how the tower implements a hybrid mass damper (HMD) system to control vibrations from earthquakes and wind. The HMD combines a tuned mass damper with an active control actuator. Two 170-ton HMD units were installed in the tower and automatically switch between active and passive modes to reduce vibrations by up to 50%. The hybrid system allows for increased efficiency and robustness compared to a purely passive or active vibration control system.

1. MAR APR MAY JUN JUL AUG
VIBRATION CONTROL OF
STRUCTURES
3 APRIL 2015
Instructor
CoursePRESENTED BY:
CHIEW SHING MEI
LIEW KOK KEI
MUHAMMAD NAIM BIN MAZELAN
111447
111458
113595
TAIPEI 101, TAIWAN

2. PRESENTATION OUTLINES
Understanding of vibration control systems of
structures
Principles associated with mass damper
Principles associated with HMD
Background of Yokohama Land Mark Tower
Application of Hybrid Mass Damper in the
Yokohama Land Mark Tower
Summary

3.  In earthquake engineering: A set of technical means aimed to MITIGATE
SEISMIC IMPACTS in building and non-building structures for enhancing
their seismic fitness. (Wikiversity).
 How to control:
1. Dissipate wave energy inside a superstructure e.g. dampers
2. Disperse the wave energy between a wider frequency range
3.Absorb the resonant portions e.g. mass damper
 Types of vibration control:
1. Passive control (TMD,TLD, viscous fluid and friction, base isolation)
2. Active control (AMD, HMD)
3. Semi-active control (combines features of active and passive control
systems)
VIBRATION CONTROL
SYSTEMS
Now: Understanding of vibration control systems of structures
Next: Background of Yokohama Land Mark Tower
 In earthquake engineering: A set of technical means aimed to MITIGATE
SEISMIC IMPACTS in building and non-building structures for enhancing
their seismic fitness. (Wikiversity).
 How to control:
1. Dissipate wave energy inside a superstructure e.g. dampers
2. Disperse the wave energy between a wider frequency range
3.Absorb the resonant portions e.g. mass damper
 Types of vibration control:
1. Passive control (TMD,TLD, viscous fluid and friction, base isolation)
2. Active control (AMD, HMD)
3. Semi-active control (combines features of active and passive control
systems)

4. Working principles of mass damper:
 Is a device mounted on structures such as buildings or bridges to reduce
the amplitude of the structures due to the vibrational motions induced by
periodic or non-periodic dynamic loading.
 Operates effectively to prevent internal discomfort and damage as well as
the outright structural failures.
 Installed mass damper moves in opposition to the resonance frequency
oscillations of the structure by means of pendulum, spring or fluid.
 Mass damper that counter-reacts the movement of building guarantees the
safety of buildings when subjected to strong wind blow or light seismic
wave.
TUNED MASS
DAMPER (TMD)
Now: Principles associated with TMD
Next: Principles associated with TMD (Con’t)
Response
force
Legend
Applied
vibrational
force

5.  These passive vibration control systems have been
widely utilized in many high-rise building structures
particularly those located at seismically active zone.
 These include Taipei 101 at Taiwan and One Rincon Hill at U.S.A.
TUNED MASS
DAMPER (TMD)
Now: Principles associated with TMD (Con’t)
Next: Principles associated with HMD
Tuned liquid damper
(One Rincon Hill)
Pendulum tuned mass
damper (Taipei 101)

6.  HMD - Combination of a passive tuned mass
damper (TMD) and an active control actuator.
 Control actuator is used in conjunction with TMD to increase the efficiency
of the HMD as well as its robustness.
 HMD depends partly on the natural frequency of a structure unlike an
AMD that is independent of the natural frequency.
 In overall, the added device adopted could reduce the structural response
relies mainly on the natural motion ofTMD.
 Energy and forces required for operating a typical HMD are far less than a
fully active mass damper system of comparable performance.
HYBRID MASS
DAMPER (HMD)
Now: Principles associated with HMD
Next: Principles associated with HMD (Con’t)
Concept of a HMD (Spencer and
Soong, 1999)

7.  Application of HMD system in Sendagaya INTES
building inTokyo (1991): HMD effectively reduces the response at the
fundamental mode by 18% and 28% for translation and torsion motions
respectively.
HYBRID MASS
DAMPER (HMD)
Now: Principles associated with HMD (Con’t)
Next: Background of Yokohama Land Mark Tower
Location of Sendagaya
INTES in map
11TH
Spencer and Soong (1999)
Sendagaya INTES

8. YOKOHAMA
LAND MARK TOWER,
JAPAN
Now: Background of Yokohama Land Mark Tower
Next: Background of Yokohama Land Mark Tower (Con’t)
BACKGROUND
 Located at Minato Mirai 21 (district ofYokohama city).
 Five-stars hotel (603 rooms), 48 floors of shops, restaurants,
clinic and offices, a 360-degree Sky Garden observatory
station at 69th floor – Main usage: Hotel and Offices.
 Completed in 1993 and it had been known as the tallest
building in Japan before it was surpassed by other buildings .
 Currently the 4th tallest structure in Japan.
 2 tuned dampers are located 282m (71st Floor) above
ground level.
 Currently has the world’s 2ND fastest elevator-traveling at
45 km/h.
Location of Yokohama

9. GENERAL STRUCTURAL INFORMATION:
YOKOHAMA
LAND MARK TOWER,
JAPAN
Now: Background of Yokohama Land Mark Tower (Con’t)
Next: Background of Yokohama Land Mark Tower (Con’t)
BuildingType Skyscraper (Tall Building)
Main Structural System Trussed tube
(Framed Tube Structure)
Main Structural Materials Structural steel and
Reinforced concrete (RC)
Facade System (Material) Curtain wall (Granite)
Design Requirement
(Vibrational Control
System)
Earthquake-proof Structure
(Hybrid Mass Damper)

10. Rankings
Global Ranking
#95Tallest in theWorld
Regional Ranking
#43Tallest in Asia
National Ranking
#2Tallest in Japan
City Ranking
#1Tallest inYokohama
YOKOHAMA
LAND MARK TOWER, JAPAN
Now: Background of Yokohama Land Mark Tower (Con’t)
Next: Application of HMD in Yokohama Land Mark Tower

11. APPLICATION OF HMD IN YOKOHAMA
LAND MARK TOWER
Now: Application of HMD in Yokohama Land Mark Tower
Next: Application of HMD in Yokohama Land Mark Tower (Con’t)
 Two 170 – tonnes of multi-step pendulum HMD were
installed in the LandmarkTower at first floor of the building’s
penthouse to improve residential habitability.
 Each unit HMD contained an additional pendulum mass
installed in the centre of a three-nested steel structure with
the three frames connected by triplicating wire
ropes.
 The HMD arranges an actuator and a damper
in parallel. Since the damper dissipates
vibration energy, a certain degree of
reliability is ensured, even though the failure
could be generated by active system.
Multistage Pendulum in Land Mark
Tower

12. APPLICATION OF HMD IN YOKOHAMA
LAND MARK TOWER
Now: Application of HMD in Yokohama Land Mark Tower (Con’t)
Next: Application of HMD in Yokohama Land Mark Tower (Con’t)
 It automatically becomes operational and switched between
an active control state and a passive control state as directed
by the sway of the building when the system senses
accelerations in excess of 0.02 m/s^2.
 An active system with many motors driven ball screw can
move the pendulum in two directions and tune it from a
period of 6 s to 4.3 s through the use of a natural period
regulator in order to correspond to natural modes of the
tower.
DUOX System adopted in
LandmarkTower

13. APPLICATION OF HMD IN YOKOHAMA
LAND MARK TOWER
Now: Application of HMD in Yokohama Land Mark Tower (Con’t)
Next: Application of HMD in Yokohama Land Mark Tower (Con’t)
Variable orifice dampers were installed between each frame
to insure stability and safety.
 The damping coefficient is 3,000 Ns/cm when the device stops
and 300 Ns/cm while the system is functioning, which
corresponds to the optimum damping coefficient for a passive
TMD.
 The efficiency of the system allowed designers to use 20% of
the mass that would have been required in a passive tuned
mass damper system.
Yokohama Land
MarkTower

14. APPLICATION OF HMD IN YOKOHAMA
LAND MARK TOWER
Now: Application of HMD in Yokohama Land Mark Tower (Con’t)
Next: Summary
 The hybrid mass damper uses 20% of the energy input that
have been required from an active mass driver.
 The end result is a system that increases the equivalent
structural damping to more than 10 %.
 This hybrid system can reduce until 50% of vibrations induced
by wind and moderate earthquakes. Yokohama Land
MarkTower

15. SUMMARY
Now: Summary
Next: References and Ending
 High-rise building structures are susceptible to vibrational motions
due to the seismic impact from earthquake and the laterally acting
wind force.
 Vibration control systems become utmost important for such
structures to have mitigated from damage caused by ground seismic
waves and wind load.
 Vibration control systems can be classified into passive control,
active control and semi-active control which enhance the building
seismic fitness.
 Yokohama LandmarkTower implemented Hybrid Mass Damper as its
vibration control system.
 HMD is the combination of a tuned mass damper and the control
actuator which is used to increase the efficiency of HMD and its
robustness.
 In Yokohama Landmark Tower, HMD operates automatically and
switches between active control state and passive control state
when excess acceleration is detected.
 The hybrid system can reduce until 50% of vibrations induced by
wind and moderate earthquake.

16. We referred to the following:
 http://web-japan.org/atlas/architecture/arc10.html
 http://en.japantravel.com/view/yokohama-landmark-tower
 http://www.emporis.com/buildings/105181/yokohama-
landmark-tower-yokohama-japan
 http://www.ce.tuiasi.ro/~bipcons/Archive/80.pdf
REFERENCES
Now: Introduction to the selected full scale structure
Next: Vibrational control system adopted in Yokohama Landmark
tower
THE END
THANK YOU FOR YOUR KIND
ATTENTION 