1. Home >
  2. Building Innovation Partnership >
  3. Research register >
  4. Seismic Pressures on Retaining Walls

Seismic Pressures on Retaining Walls 




The determination of seismic earth pressures acting against retaining walls is a complex soil-structure interaction (SSI) problem. Factors which affect these earth pressures include:

  1. The nature of the input motions which includes the amplitude, frequency, directivity and duration of the motion.
  2. The response of the soil behind, in front & underlying the wall.
  3. The characteristics of the wall, which includes the strength and bending stiffness of the wall.


The pseudo-static class of analysis is most commonly used in design and makes use of the free-field Peak Ground Acceleration (PGA ) expressed as a Seismic coefficient, C  (/g) typically obtained from national design standards (e.g., NZTA Bridge Manual, 2014).



Pseudo-static analyses


1.  Flexible (Mononobe-Okabe)

2.  Stiff (Matthewson et al., 1980)



3.  Rigid (Matthewson et al., 1980)


Question:  Can Co  be optimized for New Zealand?




  • Perform two-dimensional dynamic finite element analyses using OpenSees Consider 2 soil classes (Classes C &D) (NZS 1170.5:2004)
  • Use appropriate NZ acceleration-time histories for two zones in North Island & one for South Island, and allowance for magnitude scaling
  • Analyses for two embedded cantilever wall heights (2m and 3m) & one double propped wall height (3m, with two different prop stiffnesses)
  • Carried out 946 dynamic analyses run



Example results for Christchurch, Shallow Soils, Soil Class C





Recent updates


Last updated: 24/09/15



Timeline placeholder




• Project completed on budget and a final report was issued on 21/8/15. A further revised copy of the report was submitted due to typographical revisions and was submitted on 9/9/15.





•  N/A




• N/A



• N/A


Recommended Seismic Coefficients for use in Pseudo-Static Analysis


North Island 1: Auckland, Hamilton & New Plymouth, North Island 2: Wellington and Palmerston North and South Island 1: Christchurch.














Proudly Supported By

To read more about our supporters please select their logo


Our Major Sponsors




Christchurch Content Mangement Website