An Experimental Study on Constant Current Load Test of Reinforced Concrete based on 3D Paraffin Isolation

Abstract

Aiming at the complex corrosion degradation factors of reinforced concrete and clearing the deterioration mechanism in the constant stress state, a new type of constant current accelerated corrosion method in the saline soil environment was developed. The three-dimensional paraffin isolation specimens and the three-dimensional penetration specimens were taken as the research objects, and the Cl⁻ content and AC impedance Bode diagram were measured. The macro morphology and micro analysis were also used to evaluate the corrosion degradation laws of the two groups of specimens. A constant current three-factor system accelerated model was established for the current acceleration factor, chloride ion, and sulfate ion acceleration factor. The experimental results show that, in the constant stress test of the saline soil environmental conditions, the paraffin isolation layer can effectively isolate corrosive chloride ions, which is a brand-new research method of single factor variable control in the constant stress test. According to the basic corrosion data, the law of constant current acceleration test is summarized and divided into five corrosion degradation stages, and each stage has significant changes in the accelerated corrosion efficiency. The corrosion degradation of a constant stress test is the combined effect of constant current, positive and negative penetration of chloride ions and sulfate ions.

Keywords

Cl⁻ content / AC impedance / constant stress test / acceleration factor / full factor life cycle

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