... third of the building height. One possible contributing factor was that the period of the strong ground motion pulses may have been in a range that generally coincided with higher vibration modes for these buildings. This would have tended to amplify stresses in the middle portion of the buildings. Another possible factor was that there were changes in building strength or stiffness ... to result in stronger columns and beams that are detailed in such a way that they have less ductility than do typical U.S. buildings in high seismic zones. Hundreds of thousands of existing buildings of ...

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• Approx Pages: 97
• Grade Level: High School