Determination of Incompressibility (Bulk Modulus), Elasticity (Young’s Modulus) and Rigidity (Shear Modulus) of Uyo and Its Environ, Southeastern Nigeria

Abstract

In this work, seismic refraction was used to obtain elastic properties (shear modulus (μ), Young modulus (E), Bulk modulus (K) and lithological information in Uyo and its environ as an aid to engineering foundation. Using seismic refraction method, the top and weathered layer of the engineering foundation in the study area was investigated to determine the elastic parameters of top soil and also assess the strength of engineering foundation based on the parameter distribution. A 24-channel signal enhancement seismograph, geophones, sledge hammer and a metal plate (source) for generating seismic waves were used. The study area lies between latitudes 4˚45' and 5˚15'N and between longitudes 7˚45' and 8˚30'E in the Niger Delta region of southern Nigeria. Geologically, the area is located in the Tertiary to Quaternary Coastal Plain Sands (CPS) (otherwise called the Benin Formation) and Alluvium environments of the Niger Delta region of southern Nigeria. Shear Modulus had average values of 0.43 × 10 8 N/m 2 and 1.40 × 10 8 N/m 2 for layers 1 and 2 respectively. The average values of the Young Modulus for layers 1 and 2 were determined as 2.32 × 10 8 N/m 2 and 3.84 × 10 8 N/m 2 respectively. The average values of the bulk Modulus for layers 1 and 2 were estimated as 1.52 × 10 8 N/m 2 and 4.93 × 10 8 N/m 2 respectively.

Investigation of the shallow bedrock using the seismic refraction method – A case study in New Qena City, Eastern Desert, Egypt

“…The shallow seismic refraction is not only a non-invasive and cost-effective method but has also been used as a powerful geophysical tool in engineering and environmental investigations. The method is now widely used as the main technique for most engineering purposes, including measuring depth to the water table 1,2,[11][12][13][3][4][5][6][7][8][9][10] , delineating bedrock surface [14][15][16][17][18][19][20][21] , estimating soil type and geotechnical properties 22,23,32,[24][25][26][27][28][29][30][31] , mapping sink holes and voids [33][34][35][36][37][38][39][40][41] , and estimating rock rippability 16,[42][43][44][45][46] .…”