NEHRP Clearinghouse
- Title
- Dynamic Stiffness of Foundations: 2-D vs. 3-D Solutions.
- File
- PB286504.pdf
- Author(s)
- Jakub, M.; Roesset, J. M.
- Source
- National Science Foundation, Washington, DC. Div. of Advanced Environmental Research and Technology., October 1977, 49 p.
- Identifying Number(s)
- MIT-CE-R77-36
- Abstract
- Approximate formulae for the dynamic stiffness of embedded strip footings are developed through parametric studies. A comparison is then established between the static value of these stiffnesses and their frequency variation for two- and three-dimensional solutions. A plane strain model is demonstrated to be incapable of reproducing all the stiffness terms of a circular or square foundation. As a preliminary method of analysis, construction of similar formulae and graphs provides estimates of the natural frequency and effective modal damping provided by two- and three-dimensional finite element solutions. The magnitude of error in adopting a plane strain model may then be evaluated.
- Keywords
- Foundation engineering; Earth movements; Finite element analysis; Dynamic response; Earthquake engineering; Backfills; Stiffness; Soil dynamics; Soil structure interactions; Foundations; Footings; Earthquakes