| Title |
Influence of Environmental Factors and Reinforcing Steel Bars on the Measurement of Concrete Resistivity in RC Structures |
| Keywords |
Concrete ; Reinforcing Steel ; Corrosion Rate ; Concrete Resistivity ; Cover Depth ; Diameter of Steel ; Temperature |
| Abstract |
The measurement of concrete resistivity, when used in conjunction with potential mapping, may be used to assess the probable location and severity of reinforcement corrosion problems in in-situ RC structures. However, the presence of the reinforcing steel may itself cause an error in the measurement of concrete resistivity by providing an electrical short circuit. In this paper, the rate of corrosion of steel embedded in concrete has been evaluated by the measurement of concrete resistivity using the Wenner technique (4-probe array system) and compared with the results measured by linear polarization resistance(LPR) method which has been developed to direct measure the corrosion rate of reinforcing steel in concrete. The influence of reinforcing steel on the measurement of concrete resistivity has been also investigated using steel reinforcement with a number of different diameters, cover depth of concrete and the presence of chloride ions in concrete, and observed the effect of environmental factors on the concrete resistivity measurements to assess externally exposed reinforced concrete. The results was shown that the measurement of concrete resistivity promises to be taken quickly, accurately and without causing damage to in-situ reinforced concrete structures, in the assessment of the presence and rate of corrosion of reinforcing steel in concrete. However, reading was influenced by the presence of reinforcing bars and its influence was increased with increasing of the diameter of steel bar and with decreasing of concrete cover depth and compressive strength of concrete. The measurement of concrete resistivity was significantly influenced by the ambient temperature and rainfall. |