SPT Based Liquefaction Potentiality Index, Susceptibility & Risk Assessment in the Rohingya Refugee Camp Hills of Ukhiya, Cox’s Bazar, Bangladesh

More than one million Rohingya refugees who fled from Myanmar, had constructed temporary shelters on the loose unconsolidated sandy hills (SC-SM, SP & ML) of Ukhiya-Teknaf region, Cox’s Bazar area, Bangladesh. After entering Bangladesh, the green eco forests of Ukhiya Hills had to be destroyed by cutting trees and hill slopes as they built their shelters which eventually had destructive effects on the ecosystem of Ukhiya Teknaf region. Sands (SP-SM) are mainly uniformly graded and composed of more than 72% to 98 % sand. This research has been carried out to assess the liquefaction potentiality index vales, susceptibility using SPT and risks associated with the Ukhiya hills at different earthquake magnitudes. During earthquake at Magnitudes 5 or greater, Ukhiya hill soils are susceptible to liquefy up to a depth of 12 m.. From the Liquefaction Potentiality Index (LPI) values, risk and sensitivity analysis, it is established that the Ukhiya hills are medium to highly susceptible to liquefy at higher magnitudes (M= 5 or greater). It is also established that north western part of the camp hills are high to very high risk prone areas. Based on Liquefaction Potentiality Index (LPI) values, four seismic risk zones are identified in and around the Rohingya camp area. Some geo-engineering recommendations are also made to reduce this seismic hazard for sustainable community living in the camp area.