Vol 7 Issue 2 October 2019-March 2020

Abstract: Cracks reduced the overall strength and stiffness of concrete structures and accelerate the ingress of aggressive ions, leading to other types of concrete deterioration and resulting in further cracking. Aims: The study investigated the effectiveness of naturally occurring inorganic products of garcinia kola extracts (exudates / resins) as a protective membrane to reinforcing steel embedded in concrete. Members were immersed in severe corrosive environment and accelerated for 150days with examinations on changes of the mechanical properties of steel. Obtained flexural failure load percentile value of -29.0031% against 40.85115% and 39.32435% non-corroded and garcinia kola exudates coated specimens. Midspan deflection percentile value of 57.26586% against -36.4134% and -34.915% non-corroded and coated specimens. Average yield strength, of 460MPa, derived into 100% with 0.00% of percentile value. Average ultimate tensile percentile value of -10.0738% against 11.2023% and 11.58322% of non-corroded and coated specimens. Average strain ratio percentile value of -10.9146% against 12.25184% and 15.75587% of non-corroded and coated specimens. Average elongations percentile value of -41.3245% against 70.42903% and 74.90969% for non-corroded and coated specimens. Collated results of corroded members showed high yield strength with low applied load, high midspan deflection and elongation. Low flexural failure load with high yield. Indications showed that the attributes possessed by corroded members resulted from corrosion attacked on the surface properties of reinforcing steel and reduction in general mechanical properties of steel. Collated results from exudates / resins coated members exhibited low flexural failure load over corroded members with high, low midspan deflection over high in corroded, little elongation over high in corroded. Indications showed that coated members possessed resistance characteristics to corrosion penetration. Results from non-corroded (Controlled) members have high values of flexural failure load, low midspan deflection and yield strength, strain ratio and elongation over all corroded members.

Keywords: Corrosion, Corrosion inhibitors, Flexural Strength, Concrete and Steel Reinforcement.

Title: Residual Strength Capacity of Corroded and Coated Reinforcing Bars Corrosion Performance on the Flexural Strength of Reinforced Concrete Members

Author: Nwaobakata Chukwuemeka, Charles Kennedy, Sule Samuel

International Journal of Civil and Structural Engineering Research  

ISSN 2348-7607 (Online)

Research Publish Journals

Abstract: The fundamental concept of corrosion inhibition is the development of a stable compound with the metal surface and the formation of an adsorption complex with the metal oxide. This study evaluated the effect of salt water on reinforced concrete structures located in the costal marine environment. Corrosion accelerated simulated process was performed on non-coated and khaya senegalensis exudates / resins coated specimens for 150 days period and evaluate the actions of half cell potential, concrete resistivity and tensile strength of reinforcing steel embedded in concrete and exposed to corrosion. Results of concrete resistivity ρ, kΩcm against potential E_corr,^mV relationship showed  averaged potential E_corr control percentile average value of 30.33509% and percentile difference -69.6649% over 235.1921% corroded specimen. Results of concrete resistivity ρ, kΩcm percentile average value of 183.4935% and percentile difference 83.49351% over -30.1921% corroded specimen. Mechanical properties “ultimate strength” of control specimen value of 93.71429% and percentile difference -6.28571% over 7.138101% corroded specimen. Mechanical properties “weight loss of steel” of control percentile average value of 53.50441% and percentile difference -46.4956% over 91.49347% corroded. Mechanical properties “cross- section area reduction” of control specimen with percentile average value of 118.5055% and percentile difference 18.50551% over -15.6157% corroded specimen. Control specimens result showed no corrosion potential due to the presence of inhibitory exudates / resins that acted as an insulator to reinforcing steel embedded in corrosive environment

Keywords: Corrosion, Corrosion inhibitors, corrosion potential, concrete resistivity and Steel  Reinforcement.

Title: Half-cell potential Measurement of Concrete Resistivity of Exudates Layered Reinforcement in Chloride threshold Corrosive Environment

Author: Terence Temilade Tam Wokoma, Daso Dokibo, Charles Kennedy

International Journal of Civil and Structural Engineering Research  

ISSN 2348-7607 (Online)

Research Publish Journals