THE DEVELOPMENT AND EVALUATION OF A CONSTITUTIVE MODEL FOR THE PREDICTION OF GROUND MOVEMENTS IN OVERCONSOLIDATED CLAY

The stress-strain response of overconsolidated clay depends both on its current state and on the loading history followed to reach that state, in particular the relative directions of the current and previous loading paths. A constitutive soil model is developed which predicts this behaviour by allowing elasto-plastic deformations controlled by two nested kinematic hardening surfaces inside a conventional Modified Cam-clay state boundary surface. This relatively straightforward model requires only eight parameters, each with a rational basis, and which can be determined from a small number of well-controlled stress path tests. Predictions of soil behaviour using this model are compared with data from triaxial stress path tests. The close agreement confirms that the essential features of soil behaviour are predicted by the model. The wide implications of the use of the model in geotechnical analysis are illustrated by comparing predictions made using the model (in conjunction with finite element analysis) with data from a specially commissioned series of centrifuge tests of a circular foundation loaded on overconsolidated clay. The stress history of the soil was carefully controlled in the experiments and was replicated in the course of the analyses. The computations reproduced the main characteristics of the observed ground movement, in particular the surface profile. In contrast, conventional constitutive models of soil behaviour show vey poor predictions. This demonstrated the importance of using a model that simulates the behaviour of soil over a wide range of strain increments and with changes in load path direction. (A)

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00168505
• Corporate Authors:

  Thomas Telford Limited

  London,   United Kingdom 
• Authors:
  • STALLEBRASS, S E
  • TAYLOR, R N
• Publication Date: 1997-6

Language

• English

Media Info

• Features: References;
• Pagination: p. 235-53
• Serial:
  • GEOTECHNIQUE
  • Volume: 47
  • Issue Number: 2
  • Publisher: Thomas Telford Limited
  • ISSN: 0016-8505

Subject/Index Terms

• TRT Terms: Clay; Consolidation; Deformation; Forecasting; Loads; Mathematical models; Motion; Simulation; Soil stabilization; Stiffness
• ITRD Terms: 4177: Clay; 5791: Consolidation (soil); 5595: Deformation; 132: Forecast; 5567: Load; 6473: Mathematical model; 5483: Movement; 9103: Simulation; 5931: Stiffness
• Subject Areas: Geotechnology;

Filing Info

• Accession Number: 00739370
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• Files: ITRD
• Created Date: Aug 28 1997 12:00AM