Soil liquefaction and bearing capacity at a building site in lucknow, india under earthquake conditions.

Abstract

Problem of soil liquefaction below building foundation during earthquake shaking due to high pore water pressure in loosely packed sand deposits located below the ground water table, leading to significant loss in shear strength and causing it to flow like a viscous fluid, is a severe concern for civil engineers. In the present study, liquefaction susceptibility under earthquake conditions has been computed for 12 boreholes till a depth of 9m at a soil site in Lucknow, India. The mentioned site comes under seismic zone III as per Indian seismic design code IS 1893–Part 1 and hence a design acceleration of 0.16g was considered for building design. The seismic acceleration coefficient was also computed as per Eurocode EN1998–Part 5 and comparison in liquefaction susceptibility was carried out for the soil site. This was followed by computation of seismic bearing capacity and factor of safety at a depth of 1.5m below ground surface for the proposed building foundation. Based on the results it was observed that some selected boreholes showed susceptibility to liquefaction at certain depths under earthquake shaking. Moreover some of the selected boreholes are found to be prone to bearing capacity failure at 1.5m depth as per Eurocode EN1998–Part 5 for certain foundations. Hence the proposed results show the need for such analysis with future recommendations of remedial measures for safe design of building foundations at the site under earthquake conditions.