Physico-mechanical Properties Estimation of Upper Siwalik Sandstone using Field (MASW) and Laboratory Test, Himachal Himalaya, India

Abstract

Abstract A study on the Upper Siwalik Sandstone was conducted to determine and compare the relationship between shear wave velocity and the petro-physical and petro-mechanical characteristics of the sandstone. Two localities in the Himachal Himalaya’s Bilaspur district were sampled for collection of sandstone of Upper Siwalik. The method of Multichannel Analysis of Surface Waves (MASW) was used to obtain average shear wave velocity at 30m depth (Vs30) in the field. The shear modulus of rocks is intimately correlated with the Vs30 parameter. The Vs30 value is 185 m/s for the Majher Khad (sandstone A) region and 366 m/s for the Dharot region (sandstone B). Based on obtained Vs30 values these two regions are classified under class D and class C respectively by the National Earthquake Hazards Reduction Program (NEHRP). Both the rocks belong to Upper Siwalik Sandstone, but diversity in Vs30 and shear modulus values can be ascribed to the composition of minerals, the size of the grains, and the cementing substances present in the rock.