STUDIES OF THE EFFECT OF SOAKING ON THE DEFORMABILITY OF LOESS SOILS IN BUILDINGS AND STRUCTURES

ABSTRACT The experience of designing and constructing structures in difficult conditions of Uzbekistan shows that in the areas of distribution of loess soils, it is necessary to take into account the variability of the material composition, structure and physico-mechanical properties of soils during soaking. It should be noted that manmade flooding leads to soaking of the soil column, therefore, as a rule, it is necessary to build buildings and structures on water-saturated soils. In this case, additional precipitation may be caused by the dissolution of salt crystals in the soil when moisture enters. The study of such an issue requires, first of all, knowledge of the laws of the water-salt regime of the soil base. Тhe article presents the results of theoretical and experimental studies to identify the dependence of the modulus of soil deformation on the coefficient of water saturation. The magnitude of the soil structure weakening coefficient depends on the current average pressure: at pressures P<Pstr. value KO.S. varies for soils in a fairly wide range. But after the breakdown of natural structural bonds and the formation of new structural bonds of strengthening at P>Pf.str, the value of KO.S. decreases and approaches unity. Value KO.S. is close to unity for completely water-saturated loess soils, unless leaching of structural elements represented by soluble minerals occurs. weakening effect of water (physico-chemical resistance). The weakening effect of water on the soil structure, together with pressure, causes a sharp destruction of the structure (soil subsidence εse). Filtration of water that promotes soil dissolution can lead to a new weakening of the structure, which will be reflected in the appearance of suffusion deformation εsf.