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Civil and Environmental Engineering
University of Nevada, Las Vegas
Civil and Environmental Engineering and Construction Faculty Research
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Effect Of Overburden Height On Hydraulic Fracturing Of Concrete-Lined Pressure Tunnels Excavated In Intact Rock: A Numerical Study, Moses Karakouzian, Mohammad Nazari-Sharabian, Mehrdad Karami
Effect Of Overburden Height On Hydraulic Fracturing Of Concrete-Lined Pressure Tunnels Excavated In Intact Rock: A Numerical Study, Moses Karakouzian, Mohammad Nazari-Sharabian, Mehrdad Karami
Civil and Environmental Engineering and Construction Faculty Research
: This study investigated the impact of overburden height on the hydraulic fracturing of a concrete-lined pressure tunnel, excavated in intact rock, under steady-state and transient-state conditions. Moreover, the Norwegian design criterion that only suggests increasing the overburden height as a countermeasure against hydraulic fracturing was evaluated. The Mohr–Coulomb failure criterion was implemented to investigate failure in the rock elements adjacent to the lining. A pressure tunnel with an inner diameter of 3.6 m was modeled in Abaqus Finite Element Analysis (FEA), using the finite element method (FEM). It was assumed that transient pressures occur inside the tunnel due to …
Flow-Induced Stresses And Displacements In Jointed Concrete Pipes Installed By Pipe Jacking Method, Moses Karakouzian, Mehrdad Karami, Mohammad Nazari-Sharabian, Sajjad Ahmad
Flow-Induced Stresses And Displacements In Jointed Concrete Pipes Installed By Pipe Jacking Method, Moses Karakouzian, Mehrdad Karami, Mohammad Nazari-Sharabian, Sajjad Ahmad
Civil and Environmental Engineering and Construction Faculty Research
Transient flows result in unbalanced forces and high pressure in pipelines. Under these conditions, the combined effects of flow-induced forces along with sudden pipe displacements can create cracks in the pipeline, especially at the junctions. This situation consequently results in water leakage and reduced operational efficiency of the pipeline. In this study, displacements and stresses in a buried pressurized water transmission pipe installed by pipe jacking method are investigated using numerical modeling and considering interactions between fluid, pipe, and soil. The analyses were performed consecutively under no-flow, steady flow, and transient flow conditions, in order to investigate the effects of …