Daiwa House Industry Central Laboratory

Vibration Control Housing

We have demonstrated the seismic and vibration performance by conducting an actual size tremor experiment at the E-Defense facilities of the National Research Institute for Earth Science and Disaster Prevention.

Background and Purpose of Development

The earthquakes in Tokai, Tonankai and immediately beneath the capital city, where the likelihood of an earthquake is high in the next 30 years, have been measured 6 to 7 on the Japanese intensity scale, and there is a potential demand for measures on the market. In addition, we believe it is our mission as a housing manufacturer to provide quality housing by improving seismic adequacy based on the principle of the Basic Law on Housing Life (Issued and enacted on June 8th, 2006). In other words, it is important to reduce damages to the inner and outer materials by limiting the elasticity of the building frame in unforeseen great earthquakes and recurrent earthquakes.

We developed a vibration control housing to realize high-value housing that ensures safety and a peace of mind.

Contents of Development and Results

Vibration Control Panel

The vibration control device made of viscoelastic body pressed between steel plates is set up in the center of the Vibration Control Panel, which absorbs the energy of the earthquake by shear deforming when a relative story displacement occurs by an earthquake. The earthquake energy absorbed is released as heat, and the device keeps producing an effect without accumulating the heat.

The Picture shows Vibration Control Device

Vibration Control Effect

We demonstrated the effect of vibration control by conducting an actual size tremor experiment on an antiseismic housing and vibration control housing simultaneously at the E-Defense facilities of the National Institute for Earth Science and Disaster Prevention in Miki City, Hyogo.

The Picture shows the demonstration at E-Difence

Experimental Result 1

Both the antiseismic housing and the vibration control housing obtained the best performance data (according to our investigation) (response acceleration spectrum and response displacement) in the industry with no significant damages to the structures or inner and outer materials in the repeated shaking tests including massive seismic movement.

For example, against the wave pattern recorded (input wave level) in the Great Hanshin-Awaji Earthquake:

• 1) Response displacement of Antiseismic Housing (1st layer): Approximately 13mm.
• 2) Response displacement of Vibration Control Housing (1st layer): Approximately 7mm.

The graph shows Responsive displacement of the second floor during Kobe wave vibration (Wave recorded at the Kobe Marine Observatory during the Great Hanshin-Awaji Earthquake)

Experimental Result 2

It was confirmed that Vibration Control Housing especially has the effect of significantly reducing damages to the inner and outer materials without damaging the structure by its vibration control members absorbing the earthquake energy in repeated massive seismic movements. Furthermore, the deformation volume of Vibration Control Housing was almost half of that of Antiseismic Housing.

The degree of damages on both housings after the end of the experiment (85 tremors) was as follows.

*The above results are particular to the experiment conducted under certain conditions and may not necessarily apply to every case.