01340714

Component

In current design practice, soil-structure interaction analysis often assumes linear elastic properties of the soil and uses small displacement theory. However, there are numerous problems which require a more advanced approach. One such problem is the analysis of bridge pier stability under scour conditions where complex interactions occur between the bridge piers with footings and the surrounding soil. This type of problem requires special solution algorithms that account for soil-structure interaction and appropriate constitutive models for soil. This paper presents comparison of the four numerical approaches to modeling soil-structure interaction in the presence of large soil deformations. The commercial code LS-DYNA® was used to investigate the Lagrangian, Element Free Galerkin (EFG), Smoothed Particle Hydrodynamic (SPH) and Multi Material Arbitrary Lagrangian - Eulerian (MM-ALE) algorithms. To establish the accuracy and computational efficiency of each method, simulations were performed for the in-situ experiment of a steel loading pad penetrating into silty clay sand. The efficiency of the methods was assessed in terms of preprocessing complexity, robustness and computational cost. Solution accuracy was assessed by comparison to experimental results. The results show that all four formulations can produce reasonable predictions at large penetrations. However, the most reliable and efficient turned out to be the SPH method. This method was further used to investigate failure conditions of the pier of the Oat Ditch Bridge on I-15 in California during the August 2003 flood. The numerical simulations show that scour of the riverbed must have triggered excessive movement of the footing that led to failure of the bridge.

01329018

11-2287

English

12p

2011

Transportation Research Board 90th Annual Meeting

DVD

Figures; Photos; References (10) ; Tables (2)

Bridge piers; Failure analysis; Footings; Geotechnical engineering; Scour; Silty clays; Silty sands; Simulation; Soil structure interaction

LS-DYNA (Computer program)

Element free galerkin method; Soil deformation

California

Bridges and other structures; Geotechnology; Highways; I24: Design of Bridges and Retaining Walls

Transportation Research Board Annual Meeting 2011 Paper #11-2287

TRIS, TRB

Feb 17 2011 6:07PM