Geotechnical Aspects of Infrastructure Projects in Gypseous Soils

Abstract

This paper presents the behavior of single tension pile in collapsible soil (Gypseous soil) by experimental work. The natural Gypseous soil with 66% gypsum used in the study was brought from Salah Al-Deen governorate in Iraq while that of the sand was brought from Karbalaa governorate, south of Baghdad, Iraq. The model pile used is smooth steel pipe pile with slenderness ratios (L/D) of 10, 15, 20 and 25. The effect of the gypsum content included in the soil as well as the effect of rest time and the effect of (L/D) on the pullout capacity of pile were studied in the laboratory scale model pile. The results showed that the pullout capacity of pile in Gypseous soil is more than its capacity in Sandy soil by about 64%. When the rest time was increased, the pullout capacity of tension pile embedded in Gypseous soil decreased. Increasing (L/D) ratio of pile in Gypseous soil from 15 to 20 increases pullout capacity of pile to about 65%, while increasing that ratio from 20 to 25 increases pullout capacity of pile to about 76%.