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. ...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<sup>8</sup> N/m<sup>2</sup> and 1.40 × 10<sup>8</sup> N/m<sup>2</sup> for layers 1 and 2 respectively. The average values of the Young Modulus for layers 1 and 2 were determined as 2.32 × 10<sup>8</sup> N/m<sup>2</sup> and 3.84 × 10<sup>8</sup> N/m<sup>2</sup> respectively. The average values of the bulk Modulus for layers 1 and 2 were estimated as 1.52 × 10<sup>8</sup> N/m<sup>2</sup> and 4.93 × 10<sup>8</sup> N/m<sup>2</sup> respectively.展开更多
This article presents results of groundwater quality assessment based on some pollution indicators (pH, conductivity, total dissolved solids, total suspended solids and turbidity) carried out in Michael Okpara Univers...This article presents results of groundwater quality assessment based on some pollution indicators (pH, conductivity, total dissolved solids, total suspended solids and turbidity) carried out in Michael Okpara University of Agriculture, Umudike, Abia State, Nigeria. Twelve functional boreholes within the university campus and its environs were sampled and analyzed using the standard laboratory techniques. The results showed that the groundwater in the area was acidic with an average pH value of 5.47, which falls below the World Health Organization (WHO) standard for drinking water. The results also showed high turbidity values ranging from 86.10 to 90. 17 NTU which exceeds the WHO standard. The waters have moderate to high values of total dissolved solids, TDS (100.00 to 900.00 mg/L), total suspended solids, TSS (100.00 to 1200.00 mg/L) and conductivity (66.67 to 600.03 μs/cm). Recommendations include periodic groundwater monitoring and treatment.展开更多
The main purpose of this study is to obtain the water infiltration parameters of the soils of Michael Okpara University of Agriculture, Umudike. This could be used in simulating infiltration for these soils when desig...The main purpose of this study is to obtain the water infiltration parameters of the soils of Michael Okpara University of Agriculture, Umudike. This could be used in simulating infiltration for these soils when designing irrigation projects, thereby saving time and cost of field measurement. Field measurements of infiltration were first made using a double ring infiltrometer. The test lasted for 180 mins in each location. Infiltration values ranged from 0.03 cm/min to 0.1 cm/min. The highest value was obtained in the Forest Block. Kostiakov’s infiltration model was then applied on the field data in order to determine the soils’ infiltration parameters and equations. The model empirical constants or parameters obtained were “m” and “n”. For “m” the values were: 0.53 for the soil of Forest Block, 0.42 for Poultry block, 0.50 for P.G. block, 0.41 for the soils of Staff School and Guest House. The corresponding “n” values were: 1.37, 1.12, 0.37, 1.79, and 1.38. Infiltration equations: 0.4It1.38, 0.4lt1.79, 0.42t1.12, and 0.53t1.37 were determined for the locations. These were used to simulate data which were evaluated by comparing them with the field data. The two data sets showed closed relationships. This implied that the model could be used to simulate water infiltration during irrigation projects in the farms of Michael Okpara University of Agriculture, Umudike.展开更多
文摘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<sup>8</sup> N/m<sup>2</sup> and 1.40 × 10<sup>8</sup> N/m<sup>2</sup> for layers 1 and 2 respectively. The average values of the Young Modulus for layers 1 and 2 were determined as 2.32 × 10<sup>8</sup> N/m<sup>2</sup> and 3.84 × 10<sup>8</sup> N/m<sup>2</sup> respectively. The average values of the bulk Modulus for layers 1 and 2 were estimated as 1.52 × 10<sup>8</sup> N/m<sup>2</sup> and 4.93 × 10<sup>8</sup> N/m<sup>2</sup> respectively.
文摘This article presents results of groundwater quality assessment based on some pollution indicators (pH, conductivity, total dissolved solids, total suspended solids and turbidity) carried out in Michael Okpara University of Agriculture, Umudike, Abia State, Nigeria. Twelve functional boreholes within the university campus and its environs were sampled and analyzed using the standard laboratory techniques. The results showed that the groundwater in the area was acidic with an average pH value of 5.47, which falls below the World Health Organization (WHO) standard for drinking water. The results also showed high turbidity values ranging from 86.10 to 90. 17 NTU which exceeds the WHO standard. The waters have moderate to high values of total dissolved solids, TDS (100.00 to 900.00 mg/L), total suspended solids, TSS (100.00 to 1200.00 mg/L) and conductivity (66.67 to 600.03 μs/cm). Recommendations include periodic groundwater monitoring and treatment.
文摘The main purpose of this study is to obtain the water infiltration parameters of the soils of Michael Okpara University of Agriculture, Umudike. This could be used in simulating infiltration for these soils when designing irrigation projects, thereby saving time and cost of field measurement. Field measurements of infiltration were first made using a double ring infiltrometer. The test lasted for 180 mins in each location. Infiltration values ranged from 0.03 cm/min to 0.1 cm/min. The highest value was obtained in the Forest Block. Kostiakov’s infiltration model was then applied on the field data in order to determine the soils’ infiltration parameters and equations. The model empirical constants or parameters obtained were “m” and “n”. For “m” the values were: 0.53 for the soil of Forest Block, 0.42 for Poultry block, 0.50 for P.G. block, 0.41 for the soils of Staff School and Guest House. The corresponding “n” values were: 1.37, 1.12, 0.37, 1.79, and 1.38. Infiltration equations: 0.4It1.38, 0.4lt1.79, 0.42t1.12, and 0.53t1.37 were determined for the locations. These were used to simulate data which were evaluated by comparing them with the field data. The two data sets showed closed relationships. This implied that the model could be used to simulate water infiltration during irrigation projects in the farms of Michael Okpara University of Agriculture, Umudike.
