Volume 28, Issue 5 (September 2005)
Application of High-Speed Digital CCD Cameras to Observe Static and Dynamic Deformation Characteristics of Sand
A mesh-printed membrane was often used to evaluate the deformation of soil quantitatively, in bearing capacity tests or plain strain compression tests. The deformation of soil can be evaluated quantitatively by measuring the displacement of each mesh captured by taking pictures. However, this method requires much time to obtain the displacement and cannot be applied to the dynamic field, such as shaking table tests, because of the limitation of frame rate of the conventional analog camera. In this study, a new image processing system using a high-speed digital CCD camera was established to make it possible to evaluate the deformation characteristics of models quantitatively and automatically in both static and dynamic fields. Further, this system was applied to the shaking table tests on a retaining wall model, and the magnitude of seismic earth pressure was found to be influenced strongly by the seismic behavior of the backfill soil.