Simplified seismic response of clay embankments

• Main Author: Chee, Charleston Chao Sheng.
• Other Authors: Budi Wibawa
• Format: Final Year Project
• Language: English
• Published: 2013
• Subjects: DRNTU::Engineering::Civil engineering::Geotechnical
• Online Access: http://hdl.handle.net/10356/52616
• Institution: Nanyang Technological University

The effects of earthquakes on earth embankments are important in both pre-construction and post analysis of the embankment design. The Makdisi and Seed method is a simplified method of estimating the peak crest acceleration of an earth embankment, and has been a long-standing and renown method of estimation. This paper aims to check the accuracy of the Makdisi and Seed method in estimating the response of short clay embankments, by comparing it to finite element analysis modelling through PLAXIS 2D 2011. Models of height of 4m, 6m, 8m, 10m and 12m used in the PLAXIS modelling and the peak crest accelerations computed by the program were compared with the results of the simplified methods of calculation using the Makdisi and Seed method. The results showed an overestimation deviance of 8% to 319% for the Makdisi and Seed method using direct integration of the study accelerogram and 2197% - 6868% for the using Newmark and Hall’s simplified response spectra. The large deviance of the results of the Makdisi and Seed method calculation and the finite element modelling results could be attributed to the geometry of the study models used and the intrinsic behaviour of clay, including its cohesive nature which produces a higher damping effect compared to sand materials.