PASOFAL EXPERTS (PE) provides the full range of dam engineering services including design and remediation, instrumentation, construction monitoring, safety inspections, forensics, and removal design and construction. We employ a multi-disciplined approach to design, construction, maintenance, emergency action, safety inspection, and removal. Our staff includes geotechnical, structural, and water resources engineers. We are familiar with federal and state design and safety requirements for all classes of dams, including:

  1. Arch Dam
  2. Buttress Dam
  3. Gravity Dam
  4. Roller Compacted
  5. Concrete (RCC) Dam
  6. Embankment Dam
  7. Storage Dam
  8. Diversion Dam
  9. Detention Dam
  10. Debris Dam
  11. Coffer Dam
  12. Hydropower Dam
  13. Masonry Dam
  14. Timber Dam
  15. Steel Dam
  16. Earthen Dam
  17. Rock Fill Dam
  18. Overflow Dam
  19. Non-Overflow Dam

In order to Seismic analysis and design of a dam, PE provides a complete nonlinear analysis taking all sources of
nonlinearity into account that contribute significantly to the nonlinear behavior. It is noted that, the damage caused by earthquake shaking is normally associated with significant loss in the structural stiffness, a result of concrete cracking, yielding of steel, opening of contraction joints, slippage across the construction joints or cracking planes, and nonlinear material behavior. Additional sources of nonlinearity arise from the nonlinear response of the foundation supporting the structure, as well as the separation of the structure and the foundation at the contact surface. A complete and reliable nonlinear dynamic analysis that includes tensile cracking of concrete, yielding of reinforcements, opening of joints, and foundation/abutment displacements is becoming more practical.

PE provides a complete and reliable nonlinear analysis for the seismic safety evaluation of dams depends on continuing developments in the following areas:

  • Definition of spatially varying seismic input.
  • Energy absorption factors for reservoir sides and bottom and at infinite boundaries at the reservoir and foundation extents of the models.
  • Boundary identification and specification of significant nonlinear mechanisms (joint opening, tensile cracking, steel yielding, nonlinear material behavior under dynamic loads, etc.).
  • Development of idealized models representing the nonlinear behavior (contact surfaces for modeling contraction joints and sliding along discontinuities, and validated constitutive models for concrete cracking).
  • Development of efficient and numerical sound techniques and solution strategies for computing the nonlinear response.
  • Development of criteria for acceptable performance.
  • Identification of possible modes of failure.