Pile foundation stress-strain state in collapsible loess soil soaked from bottom to top (underground area flooding)

Conditions of stress-strain state development in loess soil in the base and around pile shaft under various cases of collapsible loess soil soaking are studied: a) Soaking from top to bottom which has been established as the basis of the effective normative documents for pile foundations in loess soils based on theoretical and experimental research; b) Collapsible soil body soaking form bottom to top (underground area flooding) which has indicated that stress state of the pile foundation base is expressed by diminishing function. A collapsible loess soil body underground soaking case with piles partially penetrating collapsible soil has indicated that stress redistribution in the soil body under the pile tip and around pile shaft is taking place when pile tips lose their bearing that eventually leads to pile bearing capacity failure and initiation of pile cap contact bearing.