Geomechanics and Engineering

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Three-dimensional modelling of water flow due to leakage from pressurized buried pipe

  • Zhu, Hong (Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology) ;
  • Zhang, Limin (Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology) ;
  • Chen, Chen (Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology) ;
  • Chan, Kit (Department of Civil and Environmental Engineering, The Hong Kong University of Science and Technology)
  • Received : 2018.01.13
  • Accepted : 2018.07.31
  • Published : 2018.11.20
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Abstract

A three-dimensional model is constructed to simulate water infiltration in an unsaturated slope from a leaking pipe. Adaptive mesh refinement and time stepping are used, assisted by an automatic procedure for progressive steepening of the hydraulic property function for better convergence. The model is justified by comparing the simulated results with experimental data. Steady-state flow is investigated considering various pipe water pressures, locations and sizes of the opening, and soil layering. The opening size significantly affects the soaked zone around the pipe. Preferential flow dominates along the pipe longitudinal direction in the presence of a loose backfill around the pipe.

Keywords

Acknowledgement

Supported by : Construction Industry Council, Research Grants Council of the Hong Kong Special Administrative Region

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