Analysis of seismically induced vibrations in turbo machinery foundation for different soil conditions: case study

• Main Authors: Sungyani Tripathy, Atul K Desai
• Format: Article
• Language: English
• Published: JVE International 2017-09-01
• Series: Journal of Vibroengineering
• Subjects: turbo machinery; raft; barrette; dynamic load; computational analysis
• Online Access: https://www.jvejournals.com/article/17436

The effect of poor soil condition and unbalanced weight of the turbo machineries can lead to increased amplitudes of vibration which are further multiplied if subjected to seismic loading. In the current work, a computational model for the turbo machinery foundation was developed in SAP 2000 software to analyze the effect of Kathmandu earthquake (2015) in five different soil conditions i.e. very hard generic rock, generic rock, generic soil, NEHRP C class and NEHRP D class. The results reveal that turbo machinery foundation with barrettes can be used in seismic areas as barrettes safeguard the foundation by absorbing/reducing the seismic load due to high specific surface and side resistance. However for poor soil conditions like NEHRP D (clay soil), it was found that barrettes alone are not sufficient to limit the vibrations induced by either dynamic loading due to rotating motion of the machineries or seismic loading. Applications of geosynthetics along with barrettes considerably reduce the vibrations at top deck for poor soil conditions.