Abstract:
A differential equation method is derived and validated for solving the stress in thick-walled cylinders which are continuous, isotropic, small deformation, linear elasticity, infinitely large, with the minimum principal stress-dependent elastic moduli, and under hydrostatic pressure stress. And combined with Griffith's strength criterion, the influence of the factors including burial depth
h, radius
r0, and support stress
p0, to the distribution of tensile stress around a circular tunnel, quantified by
σtmax (the maximum tensile stress) and
d (the distance from the location of
σtmax to the tunnel wall), is analyzed. The result shows that the differential equation method is reliable.
σtmax remains unaffected by
r0, monotonically increases with the increase of
h, and exhibits a "constant-decrease" trend with the increase of
p0.
d is proportional to
r0, demonstrates a "constant-increase-decrease" pattern with the increase of
h, and first decreases and then remains unchanged as
p0 increases.