Dynamic analysis of cylindrical foundations under torsional loading via generic discrete-element models simulating
Shi-Shuenn Chen1, Chi-Jou Kao2, Jun-Yang Shi3
1Department of Civil and Construction Engineering, National Taiwan University of Science and Technology, Taipei, 106, Taiwan. sschen@mail.ntust.edu.tw.
Scientific Reports
|November 6, 2023
Summary
A new generic model accurately simulates torsional vibrations in foundations, considering soil-structure interaction. This simplified approach improves analysis of dynamic soil-foundation interactions for irregular structures.
Area of Science:
- Geotechnical Engineering
- Structural Dynamics
- Soil Mechanics
Background:
- Torsional vibrations are critical for the dynamic response of irregular structures.
- Soil-structure interaction significantly influences structural behavior under vibration.
- Accurate modeling of soil-foundation interaction is essential for reliable structural analysis.
Purpose of the Study:
- To develop a systematic method for identifying an optimal simplified model for torsional vibration analysis.
- To propose a generic model for simulating cylindrical foundations under torsional vibrations, considering soil-foundation interactions.
- To provide practical tools for estimating foundation responses in engineering applications.
Main Methods:
- A systematic model selection process was employed to identify the optimal simplified model.
- A generic model was developed to simulate cylindrical foundations on or embedded in soil strata.
- Key soil-foundation parameters like embedment depth, layer depth, and mass ratios were analyzed.
Main Results:
- The generic model demonstrated good agreement with theoretical solutions for frequency-magnification curves and resonant responses.
- Resonant magnification factors highlighted the impact of the whipping effect due to soil-foundation interactions.
- The proposed model requires fewer parameters and performs better than existing models.
Conclusions:
- The generic model offers an efficient and accurate simulation of soil strata for torsional vibration analysis.
- Dimensionless parametric charts were developed, overcoming limitations of previous models and aiding quick engineering estimations.
- This research contributes a valuable tool for foundation vibration analysis, specifically for torsional responses.
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