Behavior of Gypseous Soil under Static and Dynamic Loading

Abstract

This study is concerned with the soaking and leaching of gypseous soil at both static and dynamic conditions. The soil used was Natural gypseous soil with 50% gypsum. Three parameters were studied (deformation ratio, dissolve gypsum salts, and hydraulic conductivity) in both static and dynamic conditions..20 tests were carried using laboratory model. A platform base connected to the loading frame was designed in a manner that allows free movement provided for dynamic test, as an earthquake. Results of experimental work revealed that the deformation ratio S/B (settlement /footing width) for the sample subjected to 10 seconds vibration was twice that of sample without vibration, while the deformation ratio was 15 times that of the sample without vibration when subjected to 30 seconds. On the other hand, 70% of hydraulic conductivity was achieved at the first 10 minutes of leaching for the model subjected to 30 seconds of vibration. That reflects the effect of earthquakes on structures constructed on such problematic soil.