Comparing the Results of Geotechnical Tests with the Well Seismic Survey to Find the Dynamic Modulus of Elasticity for the Surface Soil Sections in Hilla City

  • Zahraa N. Jedi Department of Applied Geology, College of Science, University of Babylon, Hilla, Iraq
  • Amer A. Al-Khalidy Department of Applied Geology, College of Science, University of Babylon, Hilla, Iraq
Keywords: Hilla city; Compaction; Primary and shear waves; Soil layers; Geotechnical properties

Abstract

The study area for Babylon Governorate is located roughly 110 kilometers from Baghdad, Iraq's capital city. Approximately 5,119 km2 of Iraq's total land area is occupied by it. The most common wind direction in Iraq is northwest. The results of the cross-hole survey using P and S-wave timings and velocities were discovered through a geophysical analysis of the area. In depths of 1 to 10 meters, the P-wave velocity was 482.01 m/sec and the S-wave velocity was 180.11 m/sec. 1.6-1.8 kn/m3 was the average bulk density of the research area's soils, with the lowest value of 1.6 kn/m3 in the depths of 1m and the highest value of 1.8 kn/m3 at 10 m. At depths of 1 to 10 meters, internal friction angles (ɸ) ranged from 15 to 30 degrees. The velocity  values of P and S-wave increase with depth from the surface to the depth of 10 m because of the density increase with depth in the soil (the layer compaction or soil load). Based on the ratio of compressional and shear velocities of density, elasticity and geotechnical parameters were determined. There was a wide variation in Poisson's ratio (v) between 1-10 meters, which indicates that the soil in the research area is sandy clay. The soil is considered saturated when Ko is close to 1 and the concentration index Ic exceeds 3.

Published
2023-05-26