CONSOLIDATION OF DISTURBED AND UNDISTURBED CLAY AND DIFFERENTIAL SETTLEMENT OF BUILDINGS

Abstract

Differential settlement of foundations stimulates the development of cracks in structures. However different rate of settlements could be the reason of cracks. The highest rate of settlement takes place during the consolidation period. Theoretical calculations and experimental data showed that rate of settlement of disturbed soil is higher in comparison with undisturbed soil. During the loading of undisturbed soil with structural links displacement of particles and pore pressure dissipation are slower. Pore pressure dissipation begins only after the structural links are broken, ie after the additional stress becomes higher than preconsolidation pressure. The process of disintegration of structural links is slow, therefore the rate of consolidation settlement is also slow. If there are zones of disturbed clay within the layout of building, differential settlement of building can occur. Parameters which are necessary for estimation of the primary consolidation rate of disturbed soil could be calculated using compression curve of the same soil drawn in the semi-logarithmic scale. According to the results of investigations the method described above could be used to predict the rate of primary consolidation of foundations.