Experimental and Numerical Element Tests for Granular Soils: Performance of Different Constitutive Models for Monotonous and Low-Cycle Loading

Abstract

It is known that some common constitutive models show deficits when predicting elastic and plastic deformations due to high- and low-cycle loading resulting for example from geotechnical installation processes. The object of part I of subproject 8 within the DFG research group FOR 1136 (GeoTech) is to show the performance of different constitutive models and to compare them to experimental laboratory test results and among each other. To look onto the incremental stress–strain behaviour of sand, series of drained, stress-controlled triaxial tests have been carried out to obtain strain response envelopes for monotonous loading. Here, a soil element is subjected to a constant stress increment in different directions and its strain responses are evaluated graphically. The presented laboratory tests were performed at different initial stress states. The accumulation of strains due to low cyclic loading ($N\le 50$) has also been examined for different loading directions and different sizes of stress amplitudes. All experiments have been recalculated numerically with different constitutive models, amongst them some common as well as advanced constitutive models, which have been developed recently and partly within the research group GeoTech.