Stresses Against Underground Structural Cylinders

The magnitude and distribution of static normal soil stresses against underground structural cylinders are studied herein. New results, obtained from laboratory tests on cylinders of 4.5-in. diameter buried in dry sand, are presented. The test cylinders were split into longitudinal segments, and the force acting on each 30○ arc of the soil-structure interface was measured. The experimental program included buried cylinders varying from almost perfectly rigid ones to flexible ones encased in a sheet of foam rubber. Analytical predictions were made using an idealized mathematical model and theory of elasticity to identify the significant variables and examine their effects. The results show the influence of structural flexibility and compressibility, soil properties, and depth of soil cover on contact pressures and deformations. For farther analysis of this problem, a numerical technique like the finite element method, which is well-suited to include nonlinear behavior, anisotropy, and inhomogeneity, is recommended.