Guide to remedial measures for liquefaction mitigation at existing highway bridge sites

ABSTRACT

This document deals with the methodologies that were developed to assess liquefaction risk at existing highway bridges, select appropriate ground and/or foundation improvement methods to reduce the risk of damage, design the improvements, and verify that these improvements had been achieved in the field. The report describes the methodologies developed, methodologies to assess liquefaction risks are presented in flowchart form, progressing from simple to more complex methods. A number of remediation methods are considered, including grouting compaction, vibro systems, surcharge and buttress fills, reinforcement and containment, vertical drains and underpinning. Relevant information is summarized from some numerical and laboratory (shaking table centrifuge tests) studies conducted by other researchers on the performance of liquefaction remediation