Abaqus Unified FEA

Complete solutions for realistic simulation.

Structural-Pore Pressure

The influence of water on the behavior of soils under load is extremely complex and a sophisticated coupled approach is required to provide simulation results which can be relied on to help provide confidence in design decisions.

Civil Engineering

Civil Engineers around the world use the Abaqus Unified FEA product suite and the multiphysics capabilities to simulate the behavior of soil and other natural materials used in construction of dams, tunnels foundations and other large scale engineering projects.

 

Capabilities:

  • Ability to model transient or steady-state distribution of fluid pore pressure in soils
  • Ability to model consolidation; i.e., the deformation in soils associated with the redistribution of porewater and pressure.
  • A variety of constitutive models for soils, including Mohr-Coulomb, Drucker-Prager, Cam-Clay, and Cap plasticity models. Creep behavior can be included with the Drucker-Prager and Cap plasticity models.

Example:

Construction and Earthquake Simulation of an Earthen Dam

Challenge

Earthen dam structures rely on the ability of a soil mass to remain stable when the slopes of the soil mass are less than a certain value. Under certain loading conditions, however, the stability of the mass can be compromised and these loading conditions must be considered in the design process.

Construction entails sequential placement and compaction of soil layers and the subsequent fill-up of the embanked reservoir. In the design of earthen dams, two potentially critical events must be considered: the rapid emptying (or drawdown) of the reservoir and the dynamic loading of an earthquake. The possibility of dam failure in these situations depends on the respective build-up and dissipation of the fluid pore pressure in the soil.

Solution

The soil in an earthen structure can be considered as a three phase continuum consisting of solid particles, a wetting liquid, and a gas. Abaqus provides several material models and a coupled diffusion-displacement analysis procedure for modeling such problems.

Benefit

With these capabilities, distributions of pore water pressure can be determined for assessing the safety and reliability of earthen dams designs. A preliminary assessment of the likelihood of failure for rapid drawdown conditions used failure criteria developed for earthquake analysis.

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