Accelerograph

An acceleration recorder or Accelerograph is a measuring device (accelerometer ) in conjunction with a recording device for earthquakes ( seismograph ), which is used for the measurement and recording of strong earthquakes. Such instruments are housed in a compact box and have today usually connect to the Internet.

Accelerograph in the cases of use in which the ground motion from earthquakes are so strong, that the measuring range of more sensitive seismometer is exceeded. The study of strong ground motion due to earthquakes, a branch of the earthquake sciences is committed, the attaching of acceleration recorders near major disruptions dedicated. The thus-measured data, such as the speed of the breaking of the fault can not be obtained with normal seismometers. The best known example of such studies is the Parkfield experiment, were placed at the numerous acceleration recorder near a section of the San Andreas Fault, where a major earthquake was expected that entered on September 28, 2004.

In accelerograph three acceleration sensors are perpendicular to each other, made ​​today mostly as Micro-Electro -Mechanical System (MEMS). Each of the sensors measures in this arrangement, only one direction of the acceleration occurring. From the individual measurements, the three-dimensional movement of the device can then be reconstructed.

In contrast to the continuous recording seismometer recording acceleration writers will almost always triggered by an earthquake itself. For this purpose, a threshold value of the acceleration is set in the activation of the device in which the recording is started. Without a direct Internet connection or similar arrangements, remotely access directly to the device, the maintenance of such a device is difficult. Many trips have been made already to acceleration recorders after major earthquake, only to find out that the store was filled with unimportant data, or that the device has malfunctioned.

Accelerograph also be used to monitor the response of buildings or other structures to earthquakes. With the data obtained, the vibration behavior of a building is calculated in some cases. In addition, the analysis of such data is used to improve building planning or identifying earthquake- sensitive structures in earthquake zones or otherwise secure areas.