Effects and global sensitivity analysis of vibrator-ground coupling parameters on ground force under excitation of sweep frequency. (October 2022)

• Record Type: Journal Article
• Authors: Li, Gang; Xu, Guangming; Ding, Yaping; Huang, Zhiqiang; He, Lei; Yao, Jiajia
• Is Part Of: Structures. Volume 44(2022)
• Page Start: 18
• Page End: 29
• Publication Date: 2022-10
• Subjects: Seismic vibrator -- Ground force -- Coupling parameter -- Sweep frequency -- Sobol's method -- Global sensitivity analysis; Structural engineering -- Periodicals; 624.1
• DOI: 10.1016/j.istruc.2022.07.087
• Languages: English
• ISSNs: 2352-0124

Abstract

Abstract: Ground force is the key index to evaluate the output of the seismic vibrator. To generate desired ground force, the relationship between coupling parameters and ground force should be investigated. In this paper, a method for calculating ground force is proposed based on half-space theory, and its validity is carried out by field test. According to the analysis of coupling parameters, the baseplate's mass, the mass of reaction-mass, the baseplate area, the soil elastic modulus, and the soil density are determined to be analyzed. The ground forces under the changes of coupling parameters are studied. Results show that each parameter has a different contribution to affecting the ground force at different frequencies. The heavier reaction mass is beneficial for greater vibration output below 20 Hz. Smaller baseplate mass, bigger baseplate area, and higher soil density are helpful to increase ground force in the band of 20–50 Hz. In addition, higher soil elastic modulus brings greater ground force beyond 50 Hz. Then global sensitivity analysis for ground force is investigated with Sobol's method. It indicates that the ground force is dominated by the reaction mass at low frequencies. With significant interactions, the soil elastic modulus has a great effect on the ground force at high frequencies, followed by the baseplate's mass, baseplate area, and soil density.