Dynamic response of parabolic reflector antenna subjected to shock load and base excitation considering soil-structure interaction
Base excitation; Dynamic response; Response Spectrum; Soil Structure Interaction; Transient Response
Parabolic reflector antenna structures are subjected to dynamic loads along with normal loads. Determining the dynamic response of the antenna structure subjected to short-duration loads such as earthquake loads and shock loads considering soil-structure interaction is very important to ensure the safety and functionality of the antenna system resting on soft soil. A 7.2m diameter parabolic reflector antenna with a 90-degree elevation orientation is considered for the study. A triangular pulse of shock load is applied to the antenna at different locations and responses are estimated to understand the coupling effect of soil and structure on frequencies, damping, and response. Transient response analysis is carried out. Earthquake analysis is also carried out as per IS 1893 part 4:2016 considering Zone V site location. The foundation soil below the antenna is considered homogeneous with shear wave velocity (Vs) of 100m/sec. A direct method of analysis considering soil-structure interaction as per ASCE 4-16 is performed. FEM software MSC NASTRAN is used for analysis. The absorbing boundary conditions are used to reflect radiation damping. The depth-wise stress variation in foundation soil is evaluated. The results of free vibration analysis, transient response analysis with fixed base and SSI are compared. 2022 the Author(s).
Gullapalli V.; Raghunandan K.R.; Reddy G.R.
Current Perspectives and New Directions in Mechanics, Modelling and Design of Structural Systems - Proceedings of the 8th International Conference on Structural Engineering, Mechanics and Computation, 2022, pp. 132-137.
Gullapalli V., Department of Civil Engineering, Christ University, Bangalore, India, ECIL, Hyderabad, India; Raghunandan K.R., Department of Civil Engineering, Christ University, Bangalore, India; Reddy G.R., BARC, HBNI, Mumbai, India