International Journal of Earth Sciences Knowledge and Applications

Yazarlar: Ogechukwu Anastasia BEN-OWOPE, Elizabeth Ifenyinwa OKOYEH, Michael Uchechukwu ANAEKWE

Konular:Yerbilimleri, Ortak Disiplinler

Anahtar Kelimeler:Groundwater level,Quality,Permissive limit,Concrete,Foundation

Özet: Water is a vital necessity for human existence; howbeit it has been a major concern over the years especially in the built industry where structural integrity has remained a mirage. Groundwater conditions especially the chemical composition and its potential attack on concrete foundations is paramount toward ensuring safe and economic design of structures. The presence of sulphate, chloride as well as pH above the permissible limits in groundwater may result to deterioration of either the concrete itself or the steel reinforcement. This condition if not checked overtime may ultimately lead to structural collapse resulting to loss of lives and properties. Also, increase in groundwater level can either delay or bring construction activities to abrupt end due to uncontrollable influx of water especially during excavation. Thirty water samples were collected from wells and boreholes in different locations within the study area and subjected to chemical analysis in accordance with NIS, BS, DIN and WHO standards to determine their degree of corrosivity on concrete foundations. Six wells were also monitored to determine the extent of groundwater level fluctuation. The result of the analysis indicated a pH value of 4.8 to 10.6 with mean temperature of 25.48°C. Seven out of 30 samples tested for iron exceeded the permissive limit. The sulphate value ranges from 10 to 230 mg/L while chloride content is from 10 to 180 mg/L among others. The groundwater level monitoring revealed a seasonal pattern of fluctuation influenced by rainfall. It is recommended that precautionary measures be taken against groundwater conditions and its effect on concrete foundations in the study area and should be considered at the design stage.

---