Location
San Diego, California
Presentation Date
29 May 2010, 8:00 am - 9:30 am
Abstract
The effect of earthquakes on the behavior of soil and/or structures is usually investigated using earthquake-like signals as input for loading. This holds true for most of numerical and experimental simulations. In contrast to those approaches sinusoidal excitation was used here. The benefit of this type of excitation is an increased observability of the system, which is a precondition for a systematic investigation. Since sinusoidal excitation allows a gradually, step by step increase of the applied loading, the state of the soil (density and effective stress) as well as pore water pressure are transient. Therefore they are varying slowly and the modes of vibration are changing with time accordingly. The modes can be identified by regarding the contour of a soil column for instance. The evolution and distribution of pore water pressure (up to liquefaction) has to be captured simultaneously. A further advantage of this method is that asymptotic behavior can be investigated for the evolutions of pore water pressure and settlement of the surface with an increasing number of cycles. On the base of a numerical study some test in a shake-box will be shown using the described concept. Numerical modeling of soil behavior under cyclic respectively dynamic loading requires the application of nonlinear constitutive laws. With the used FE-model it is possible to observe the dependence of excitation amplitude, frequency and initial state on the transient amplification of the sinusoidal input signal up to an onset of liquefaction. The appropriate experimental investigations confirm the numerically observed behavior. Therefore a shake-box under 1-g conditions with smooth boundaries is used for the tests. They were performed with a homogeneous soil column (about 0.8m length, 0.6m width, 2.1m height) from medium-grained quartz sand under saturated conditions.
Department(s)
Civil, Architectural and Environmental Engineering
Meeting Name
5th International Conference on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics
Publisher
Missouri University of Science and Technology
Document Version
Final Version
Rights
© 2010 Missouri University of Science and Technology, All rights reserved.
Creative Commons Licensing
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.
Document Type
Article - Conference proceedings
File Type
text
Language
English
Recommended Citation
Wienbroer, Holger; Rebstock, Daniel; and Huber, Gerhard, "Numerical and Experimental Investigation of Soil Behaviour Under Stationary Excitation" (2010). International Conferences on Recent Advances in Geotechnical Earthquake Engineering and Soil Dynamics. 11.
https://scholarsmine.mst.edu/icrageesd/05icrageesd/session08/11
Included in
Numerical and Experimental Investigation of Soil Behaviour Under Stationary Excitation
San Diego, California
The effect of earthquakes on the behavior of soil and/or structures is usually investigated using earthquake-like signals as input for loading. This holds true for most of numerical and experimental simulations. In contrast to those approaches sinusoidal excitation was used here. The benefit of this type of excitation is an increased observability of the system, which is a precondition for a systematic investigation. Since sinusoidal excitation allows a gradually, step by step increase of the applied loading, the state of the soil (density and effective stress) as well as pore water pressure are transient. Therefore they are varying slowly and the modes of vibration are changing with time accordingly. The modes can be identified by regarding the contour of a soil column for instance. The evolution and distribution of pore water pressure (up to liquefaction) has to be captured simultaneously. A further advantage of this method is that asymptotic behavior can be investigated for the evolutions of pore water pressure and settlement of the surface with an increasing number of cycles. On the base of a numerical study some test in a shake-box will be shown using the described concept. Numerical modeling of soil behavior under cyclic respectively dynamic loading requires the application of nonlinear constitutive laws. With the used FE-model it is possible to observe the dependence of excitation amplitude, frequency and initial state on the transient amplification of the sinusoidal input signal up to an onset of liquefaction. The appropriate experimental investigations confirm the numerically observed behavior. Therefore a shake-box under 1-g conditions with smooth boundaries is used for the tests. They were performed with a homogeneous soil column (about 0.8m length, 0.6m width, 2.1m height) from medium-grained quartz sand under saturated conditions.
