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Flow Chart for Evaluation and Mitigation of Liquefaction Hazards
to Bridge Approach Fills
(page 2)
STEP 6
Is remedial ground treatment warranted?
(ODOT Liquefaction Mitigation Policy)
STEP 7A
Develop Liquefaction Mitigation Program including:
1. Select method(s) of remedial soil improvement (Chapter 5)
2. Evaluate constructability issues pertaining to soil
improvement methods (e.g., access, construction vibrations,
noise, project duration) Develop preliminary cost estimates
for various soil improvement schemes.
STEP 7B
Establish the Extent of Soil Improvement
1. Determine the volume of soil to be treated (iterative seismic
performance analysis outlined in Chapter 7)
2. Limit equilibrium methods (static, pseudostatic, sliding-block)
a. Effective stress analysis
b. Total stress analysis using residual strengths
Has the minimum allowable factor of safety been exceeded?
3. Numerical dynamic effective stress modeling (Chapter 6)
Have soil deformations been reduced to an allowable extent?
Limit states for foundation and bridge elements have not been exceeded?
4. Estimate cost for the preferred soil improvement application.
STEP 8
Proceed with Seismic Design of
Approach Embankments, Abutments and Foundations
Apply established methods of
analysis and design for competent soils
Figure 8.1 (continued): Flow Chart for Evaluating and Mitigating Liquefaction Hazard
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