The Effect of Densification on Pieve di Cento Sands in Cyclic Simple Shear Tests
The main aim of this work is to study the effectiveness of densification as a mitigation technique against liquefaction, by means of cyclic simple shear tests carried out on specimens reconstituted at several relative densities. The adopted cyclic simple shear apparatus works with a sophisticated control system, which allows to carry out tests in k0 condition without using confining rings. Two different Italian sands were tested, both retrieved at Pieve di Cento (Emilia Romagna Region, affected by 2012 earthquake) at different depths. The results of cyclic simple shear tests show that densification increases the resistance to liquefaction. The expression of Booker et al. (1976) has been also used to simulate the trend of excess pore pressure ratio with the ratio between number of cycles and number of cycles at liquefaction of the experimental undrained cyclic tests.
KeywordsSoil liquefaction Densification Cyclic simple shear tests
This work was carried out as part of the European project Horizon 2020 – Assessment and Mitigation of liquefaction potential across Europe: A holistic approach to protect structures infrastructures for improved resilience to earthquake – induced liquefaction disasters – “LIQUEFACT” (grant agreement No. 700748).
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