Study of the Vibration Transmission and Path Recognition of an Underground Powerhouse Using Energy Finite Element Method

Abstract EN

Taking the underground powerhouse of a pumped storage power station as the engineering background, this study established a 3D finite element model of the main and auxiliary powerhouse and performed the dynamic harmonica calculation for its fluctuating pressure.

Based on the power flow theory, the ANSYS Parametric Design Language (APDL) procedure was completed to calculate the power transmission in the powerhouse.

The law of dominant path recognition was first proposed to assess the structure’s dominant transmission using a numerical solution on nodes in the model.

The conductivity of the closed-cell foam that filled the structure’s joints was examined, as were the dynamic transmission features of the rock around and beneath the powerhouse.

The results indicated that, as a structural joint filler, closed-cell foam could actively restrict vibration transmission, and the directions of dynamic transmission were mainly perpendicular to and along the river in the foundation rock.

Approximately 20 percent of the foundation rock beneath the auxiliary powerhouse was disturbed by the concrete around the spiral case and induced vibrations in the powerhouse’s lower floors.

Vibration in the higher floors was derived from downstream rock, and the dynamic transmission effect had a clear advantage along the horizontal direction.