Ground motions a!ected by directivity focusing at near-"eld stations contain distinct pulses in acceleration, velocity, and displacement histories. For the same Peak Ground Acceleration (PGA) and duration of shaking, ground motions with directivity pulses can generate much higher base shears, inter-
Deterministic and probabilistic representation of near-field pulse-like ground motion
β Scribed by Abbas Moustafa; Izuru Takewaki
- Publisher
- Elsevier Science
- Year
- 2010
- Tongue
- English
- Weight
- 656 KB
- Volume
- 30
- Category
- Article
- ISSN
- 0267-7261
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β¦ Synopsis
The response and damage assessment of engineering structures under near-field ground motions is currently of great interest. Near-field ground motion with directivity focusing or fling effects produces pulse-like ground motion that has characteristics different from those of ordinary records. This paper develops simple deterministic and probabilistic models for near-field pulse-like ground motions. These models belong to the class of engineering models that aim to replicate some of the gross features observed in near-field records. The ground velocity is expressed as a steady-state function or a stationary random process modulated by an envelope function. Both models account for the nonstationarity and the multiple pulses in the ground velocity. While the deterministic model is similar to some of the models developed earlier, the probabilistic model facilitates handling uncertainties in the ground motion and variability in the structure's properties. For instance, this model combined with structural reliability methods can be used for reliability assessment of structures under near-field random ground motion. The reduction of the structural response by adding supplemental dampers is also investigated.
π SIMILAR VOLUMES
The focus of this paper is the structural response of multi-story structures to near-fault ground motions, and whether structural response is dominated by the ground motion pulses present in forward-directivity ground motions. Also considered is whether simplified pulses are capable of representing
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