Centrifuge Modeling and Analysis of Level Site Liquefaction Subjected to Biaxial Dynamic Excitations: Fid-Bau Portal

Centrifuge Modeling and Analysis of Level Site Liquefaction Subjected to Biaxial Dynamic Excitations

Shafee, Omar El / Abdoun, Tarek / Zeghal, Mourad

The paper presents a series of centrifuge tests simulating a level site consisting of granular soil deposits subjected to various bi-axial and uniaxial base excitations. Synthetic sinusoidal waves were used as base excitations to test loose models under biaxial and uniaxial shaking. Dense arrays of accelerometers were used to monitor the deposit response along with pore water pressure transducers. Two uniaxial tests and one bi-axial shaking test were conducted on three similar soil models to study the impact of multidirectional shaking on the generation of soil liquefaction. The two uniaxial shaking tests consisted of: i) test with input energy content using the arias intensity is similar to that of the bi-axial input shaking; and ii) test with 10% increase in one of the components of the biaxial shake amplitude, as commonly done in practice for uniaxial simulation of multidirectional field shaking. The observed acceleration and pore pressure are used along with non-parametric identification procedures to estimate the corresponding dynamic shear stress-strain histories. The measured results along with the obtained stress and strain histories are used for two purposes. First, to shed the light on the properties of liquefaction occurring through the stratum subjected to uniaxial shaking. Second, to show the difference in soil behavior when it is subjected to biaxial shaking.