Investigation of the first quasi-rectangular metro tunnel constructed by the 0−θ method

Quasi-rectangular shield tunneling is a cutting-edge trenchless method for constructing metro tunnels with double tubes, owing to its advantages in saving underground space and reducing ground disturbance. However, the conventional quasi-rectangular shield tunneling method is not applicable when constructing a tunnel without a center pillar,...

External surface cracked offshore steel pipes reinforced with composite repair system subjected to cyclic bending: An experimental investigation

In this paper, we experimentally studied the external surface crack growth in steel pipes reinforced with Composite System Repaired (CRS). CRS reinforced surface cracked API 5L X65 pipes were tested, containing three initial notch sizes and four reinforcement schemes. During the tests, the crack growth results, as well as the strain on the...

An investigation on the circumferential surface crack growth in steel pipes subjected to fatigue bending

In the present paper, we propose an analytical method to calculate the Stress Intensity Factor (SIF) of circumferential surface cracks in steel pipes subjected to bending. In light of pipe geometry and bending load case, the analytical formula is raised by introducing new bending correction factors and new geometry correction factors on the...

Probabilistic Analysis of Velocity Distribution under Earth Embankments for Piping Investigation

Piping has been attributed as a major cause of dam and embankment failures. Current national prediction models to predict piping use the hydraulic gradient between the upstream and downstream water levels as an indicator. They are deterministic and take no account of preferential pathways. However, piping usually initiates from a discrete...