Print ISSN: 1681-6900

Online ISSN: 2412-0758

Keywords : Clayey Soil


2D and 3D Resistivity Imaging for Soil Site Investigation

Hussein H. Karim; Mahmoud R. AL- Qaissy; Nadia A. Aziz

Engineering and Technology Journal, 2014, Volume 32, Issue 1, Pages 249-272

Electrical Resistivity Imaging (ERI) method is one of the most promising
techniques which is well suited to applications in the fields of geohydrology,environmental science and engineering. The present work is aimed to show the efficiency of 2D Electrical Resistivity Imaging (ERI) and Induced Polarization (IP) in probing the subsurface soil for site investigation and differentiating the clayey soil layers as it is a common practice to measure the IP sounding along with resistivity for
correct interpretation of field data. The study has demonstrated the practical application of 2D ERI and IP tomography along 7 lines using Wenner- Schlumberger array. The data analysis comprises of 2D inversions using the RES2DINV software, thus 2D electrical resistivity and IP imaging sections have been obtained. The depth of investigation was 4 m, and resistivity values range from <1 to 292 ohm.m. Two electrical layers were recognized: the upper layer with high resistivity (7-71 ohm.m)
represents the loamy soil extends to a depth around 1.3 m; and the second layer with low resistivity (<1-9 ohm.m) represents the clayey layer. Some anomalous low and high electric zones are appeared reflecting the inhomogeneity in deposits. The IP values are ranging from -2 to 15 mV/V showing good confirmation with resistivity data, where high chargeability are associated with low resistivity. The study reveals that combining IP with resistivity surveys is recommended since IP is, sometimes, very effective in relieving ambiguity in interpretation.

Assessing and Evaluating the Effect of Organic Matters on Clayey and Silty Soil Stiffness Properties

Aqeel Al Adilil; Kawther Y.H. Al-Soudany

Engineering and Technology Journal, 2013, Volume 31, Issue 19, Pages 103-119

Construction of building and other civil engineering structures on weak or soft soil is highly risky because such soil is susceptible to differential settlements, poor shear strength, and high compressibility.Organic soils are difficult to deal with due to their particular characteristics such as high compressibility and poor strength and, as a consequence, criteria based on common mineral soils may not generally be applied to them. The objective of this research is to investigate and assess adding different percentages of organic matters on soil stiffness, from laboratory experimental work, and to investigate the effectiveness of animal disposals and plants pieces (leaves) ontwo soil types.
Hence, in the present research, mixed organic materials have been used, and it was randomly included in to the soil at four different percentages of organic content, i.e. 5, 10, 15, and 20% by the weight of two main raw, silty soil and clayey soil. The research revealed from the laboratory tests that when organic mattersincreased the stiffness of both clayey and silty soil were reduced, and the reduction were from 16.5% to about 61% with 5 and 20% adding percentage of organic matter respectively. While the liquidity and plasticity increased from the reference soil (without organic materials) as well as the swelling index increasing for the two types of tested soils. Moreover the research indicates the percentage of organic contents played an important role in the development of the vertical displacement of the clayey and silty soil under loading.

Differentiating Clayey Soil Layers from Electrical Resistivity Imaging (ERI) and Induced Polarization (IP)

Nadia A. Aziz; Mahmoud R. AL- Qaissy; Hussein H. Karim

Engineering and Technology Journal, 2013, Volume 31, Issue 17, Pages 3216-3234

Electrical Resistivity Imaging (ERI) method is one of the most promising
techniques which is well suited for the applications in the fields of geohydrology,
environmental science and engineering. The present work is aimed to show the
efficiency of 2D Electrical Resistivity Imaging (ERI) and Induced Polarization (IP) in
probing the subsurface soil for site investigation and differentiating the clayey soil
layers as it is a common practice to measure the IP sounding along with resistivity for
correct interpretation of field data. The study has demonstrated the practical
application of 2D ERI and IP tomography along 7 lines using Wenner- Schlumberger
array. The data analysis comprises of 2D inversions using the RES2DINV software,
thus 2D electrical resistivity and IP imaging sections have been obtained. The depth of
investigation was 4 m, and resistivity values range from <1 to 292 ohm.m. Two
electrical layers were recognized: the upper layer with high resistivity (7-71 ohm.m)
represents the loamy soil extends to a depth around 1.3 m; and the second layer with
low resistivity (<1-9 ohm.m) represents the clayey layer. Some anomalous low and
high electric zones are appeared reflecting the inhomogeneity in deposits. The IP
values are ranging from -2 to 17 mV/V showing good confirmation with resistivity
data, where high chargeability are associated with low resistivity. The study reveals
that combining IP with resistivity surveys is recommended since IP is, sometimes, very
effective in relieving ambiguity in interpretation.