Field Measurement and Numerical Analysis for Buried Large Diameter Steel Pipes

This paper presents an overview of field tests for buried pipe, which were conducted using steel pipes with 3500 mm diameter and 26 mm thickness. In this full-scale test, five kinds of construction site were employed. The depth of soil cover was approximately 3.0 m in every case. Sheet pile method was employed in Case-5, and open-cut method was conducted in the other cases. Displacement transducers were installed in the pipe and strain gauges were circumferentially attached to the inner of the pipe. The deformation of pipe was observed for over a year by those measures. Therefore, it is found that the behavior of the buried pipe was strongly influenced by backfilling methods. In addition, FEM analyses were conducted to confirm the behavior of soil-pipe interaction. Thus, it is found that the inhomogeneous strength of backfill materials brings local deformation of the pipe.