G MS THESIS_final version_Maxim Prokudin.pdf - Digital Repository ...

19Soil conditions at the site were evaluated to consist of urban fill underlain by a 1.7m - 2.4 mlayer of silt. Very soft to stiff clay and dense sand layers were found beneath the layer of silt.Urban fill featured cobbles and large diameter stones. Moisture content of the collectedsamples varied between 10 and 18 percent. Groundwater table was found to be located atapproximate elevation depth of 5.5 m. The SPT (Standard Penetration Test) number of blowsfor the urban fill layer was found to range between 6 and 20, while the layer of silt wascharacterized by the N value ranging between 2 and 4. The SPT N values were found torange between 4 and 40 for the soft to stiff clay and dense sand layers.The load test results have shown group efficiency to be equal to unity. Moreover, the totalstress cell results obtained for the group of three pier footings showed a stiffness ratio on theorder of 4 at low compression loads and stiffness ratio of 6 at high compression loads(Bucher et al., 2008). Load-settlement results are provided in Figure 8. It was noticed for thegroup of three footing to undergo a greater amount of settlement under lesser load than theunit cell, however no explanation to the anomaly was provided by the authors.Applied load at top of the footing (kg)00 20000 40000 6000012Settlement (mm)3456789Tell tale footing test1.0m x 1.0x Unit cellfooting test1.8m x 1.8m (3 piers)Modulus testTell tale modulus test10Figure 8: Modulus and footing load test results (reproduced per Bucher et al., 2008)