Assistant professor, Marquette University, Milwaukee, Wis.
Professor of civil engineering, The Technological Institute, Northwestern University, Evanston, Ill.
Pages: 14 Published: Jan 1977
This paper describes the development of a finite-element computer program to simulate the structural behavior of a buried concrete pipe. The influence of the soil-structure interaction phenomenon is approximated by using appropriate material properties for the bedding and backfill, and by employing empirical hinging mechanisms which enable simulation of the progressive cracking behavior in the model of the concrete pipe. A second approximation, in which the pipe is represented as a linear frame, is introduced for the calculation of internal stress resultants. Various iteration techniques are employed to ensure deformation compatibility between the two pipe models. The results from full-scale experimentation are then used to validate the analytical models.
This model of the soil-pipe system was combined with appropriate serviceability and ultimate strength design criteria for reinforced concrete pipe to produce a comprehensive computer program for the design of buried concrete pipe. The resulting program, entitled NUPIPE, accounts for nonlinear soil-structure interaction, and permits the engineer to obtain the structural design of a given size pipe having a specified fill height and installed in any manner (that is, arbitrary bedding or backfill procedures or both).
The applicability of the new design method is demonstrated by designing various installations. The required steel areas for these installations are compared with those obtained by use of the current design method, and the differences are discussed.
concrete pipe, soil-structure interaction, computer simulation, culverts, displacement, design, field tests, pipes, research, structural analysis, structural engineering, ultimate strength, strength criteria, finite-element method
Paper ID: STP38077S