Assessment of Ground Improvement by Vibro-compaction Method for Liquefiable Deposits from In-Situ Testing Data

作者:Duan, Wei; Cai, Guojun*; Liu, Songyu; Yuan, Jun; Puppala, Anand J.
来源:International Journal of Civil Engineering, 2019, 17(6B): 723-735.
DOI:10.1007/s40999-018-0348-2

摘要

Seismic piezocone penetration tests, resistivity piezocone penetration tests, and standard penetration tests (SPT) were conducted to quantitatively assess the effects of soil improvement by vibro-compaction. The differences of piezocone penetration test (CPTU) basis readings, improvement index for densification, electrical resistivity of soils, and state parameters before and after ground treatment were analyzed, and the effect of the increase in stiffness on the site response was also analyzed for the effect of densification. A combination of shear wave velocity, V-s, and cone tip resistance, q(c), was used for the interpretation of the changes of coefficient of earth pressure at rest, K-0, and mean grain size, D-50, before and after compaction. The dissipation process of excess pore pressures during vibro-compaction has been presented to show the effect of drainage. In addition, liquefaction potential was also estimated by CPTU and SPT for its effect of reinforcement. The results showed that the liquefied soil was densified and the use of a combination of in-situ tests could be used for ground improvement needed to mitigate liquefaction.