Current Trends in Design and Analysis of Paper Machine Foundations

Current trends in the design and dynamic analysis of paper machine foundations to ensure satisfactory performance are presented in this paper. Space frame foundations for modern high speed paper machines are governed by the requirements to meet stringent alignment/deflection tolerances and dynamic stiffness requirements specified by the machine manufacturer. The current design approach considers the complete machine-foundation-soil interaction. The dynamic response analysis is commonly conducted using a suitable finite element computer code in which the soil is modelled by equivalent springs. Damping is also included in the response calculation. Appropriate stiffness and damping parameters to model the foundation soil or soil/pile system are obtained from complex, frequency-dependent impedance functions derived from analytical and numerical solutions of continuum foundation models. Two case histories are presented to illustrate the use of forced vibration testing to aid in the machine foundation design process