000			a
999			_c18538 _d18538
003			OSt
005			20221231111523.0
008			221231b xxu||||| |||| 00| 0 eng d
040			_aAIKTC-KRRC _cAIKTC-KRRC
100			_919505 _aIndraratna, Buddhima
245			_aInternal instability and fluidisation of subgrade soil under cyclic loading
250			_aVol.52(5), Oct
260			_aUSA _bSpringer _c2022
300			_a1226-1243p.
520			_aRapid globalisation and the rise in population have substantially increased the demand for rail infrastructure which have been critical in transporting passengers and freight across landmasses for over a century. The surge in demand often leads to the construction of railway lines along with unfavourable soil conditions which result in different forms of substructure challenges such as uneven track deformations, ballast degradation, and subgrade mud pumping. A widespread site investigation along the eastern coast of New South Wales, Australia, indicated the prevalence of mud holes or bog holes along the tracks. The field studies suggest that low-to-medium plasticity soils are highly susceptible to mud pump when subjected to heavy axle loads under impeding drainage conditions. Subsequent laboratory investigations conducted on the remoulded soil samples collected from the sites indicated the sharp rise in cyclic axial strains and excess pore pressures along with the internal redistribution of moisture content as the governing mechanism for mud pumping. Numerical simulations performed using discrete element method coupled with computational fluid dynamics show that at a high hydraulic gradient, there is a substantial loss of soil contact network which leads to the upward migration of soil particles. The role of plastic fines and the inclusion of geosynthetic layer between the ballast and subgrade are also discussed in this paper. It was observed that the addition of 10% of cohesive fines increased the resistance of subgrade soils to mud pumping. On the other hand, geosynthetic inclusions not only assist in dissipating high cyclic excess pore pressures but also inhibit the upward migration of fine particles.
650		0	_94621 _aCivil Engineering
700			_919506 _aSingh, Mandeep
773	0		_dSwitzerland Springer _x 0971-9555 _tIndian geotechnical journal
856			_uhttps://link.springer.com/article/10.1007/s40098-022-00616-0 _yClick here
942			_2ddc _cAR