Build-Up of Pore Water Pressure in Coarse-Grained Soils of Similar Fabric
摘要
The soil fabric can be manifold depending on the art of the deposition process creating the grain skeleton. It can be expected that a certain deposition method creates a specific type of the soil fabric. This deposition fabric is linked to a particular soil density. When expressed as a relative density with help of the limit densities from the standard index tests, a large range of the relative densities of different sands for one deposition method can be observed. The impact of this variation of the relative density at one particular deposition method on the build-up of the excess pore water pressure (PWP) should be clarified. The newly developed PWP Tester enables a fast testing of the excess PWP build-up during undrained cyclic shearing in sandy soils. The tested specimens are created by water sedimentation and thus have a comparable fabric. Although the relative densities after the soil deposition are significantly different for different soils, the rate of the PWP evolution during undrained shearing is well comparable. Consequently, the relative density should not be considered as a main factor controlling the excess PWP build-up.