Liquefaction Potential of Roorkee Region Using Field and Laboratory Tests

Abstract

Before taking up the ground improvement of a site, assessment of liquefaction potential of a region is very important. This also helps in seismic microzonation of the area. It can be rationally performed if the data of site (using either field tests or laboratory tests) are available. The aim of the present study is to evaluate liquefaction potential of Roorkee (India) region. For this purpose the liquefaction resistance of the soil, within the radius of 30 km of Roorkee, was evaluated using two different approaches. First is the field approach based on standard penetration test (SPT) N-Value and second is the laboratory approach employing mean grain size distribution (D 50 ). Investigation was carried out at five different locations by conducting SPT tests and collecting soil samples at regular interval. The cyclic shear stress due to earthquake loading was examined using simplified method as well as using ground response analysis. The factor of safety against liquefaction was evaluated at different depths for all the sites using both field and laboratory data. It was found that the factor of safety against the liquefaction using field approach is marginally greater than that using the laboratory approach for all the sites. Also the factor of safety using ground response analysis is significantly smaller than that using simplified method. Thus it was concluded that use of simplified method may not be adequate.

Investigation of the similarity between physical tests and fatigue simulation of flange yoke made of C45 E material used in cardan shafts

“…The examination of the fracture regions of the flanged yokes reveals that typically all of them have fractured at the splined section just above the flanged yoke connection hole, having a corner radius, Figure 8. This is in accordance with the literature as stated [7–9].…”

“…On the whole, the yokes are mainly subjected to torsional loading, while the universal joint body and inner faces of the yokes are additionally subjected to shear loading. The overall failure of the yoke assembly is mainly due to fatigue caused by excessive and improper application of combined torques, shock loads and unexpected overloads and also material, design and manufacturing faults [7, 8].…”

Correlation Between Shear Wave Velocity (Vs) and SPT Resistance (N) for Roorkee Region

“…Drilling could not be done beyond 12.5 m. The water table is at shallow depth i.e. B6 m, Kirar and Maheshwari [14] examined the dynamic soil properties at high strain using cyclic triaxial tests for four sites [2][3][4][5] listed in Table 1, Muley et al [15] evaluated liquefaction potential of first five sites listed in Table 1. Index properties and SPT resistance of all the ten sites has been evaluated and discussed below.…”

Static and dynamic characterization and response analysis of soils from northern India

“…The soil layer from 6 to 9 m is prone to liquefaction. Muley et al [43] used laboratory test and SPT-N data for the estimation of liquefaction potential for Roorkee region, Uttarakhand, for SP-type soil. The soil layer of depth 1.5 m-6 m is prone to liquefaction.…”