Improvement of Liquefiable Foundation Conditions Beneath Existing Structures.

Abstract : The stabilization and improvement of liquefiable soils beneath existing structures is currently feasible within the state of knowledge and assumptions concerning liquefiable soils and earthquake excitation. This can be done directly or indirectly to mitigate the effects of liquefaction and to assure safe performance. At the present time there has been essentially no experience with remedial actions in liquefiable soils at existing structures and no general method is applicable for all conditions. Each site is unique and will require specific engineered solutions. This report presents and briefly discusses methodologies that have been deemed potentially applicable for remediating liquefiable soils beneath existing structures. A comprehensive bibliography is included on the feasible methods. The most important factors for construction in choosing remedial methods/techniques are: (a) the verfiability of improvement and stabilization, and (b) the assurance that the method itself will not create unsafe and unstable conditions under static and dynamic loading. Originator-supplied keywords: Admixture stabilization; Compression; In-situ deep compaction; Injection and grouting; Liquefaction; Pore-water pressure relief; Remedial treatments; Soils; Soil reinforcement; and Thermal stabilization.