Effect of Crack on Durability of RC Material under the Chloride Aggressive Environment

Abstract

Exposed to aggressive environments, the rebar in reinforced concrete (RC) bridges will be corroded gradually. Durability of RC material mostly depends on the rebar corrosion behavior. In this research, influences of crack on rebar corrosion were investigated. Firstly, RC specimens with different crack number, width and spacing were prepared and the rebar corrosion was conducted through an accelerated chloride penetration method. Then, corrosion current densities of rebar were calculated from electrochemical test methods including liner polarization (LP), Tafel potentiodynamic polarization (TPP) and electrochemical impedance spectroscopy (EIS) measurements. Finally, the discussion was presented about a more reasonable electrochemical testing method for rebar corrosion in RC material. Besides, the significant influence factor among crack width, number and spacing was evaluated based on both One-way analysis of variance (One-way ANOVA) and Turkey's honest significant difference (Turkey's HSD) test. The results revealed that a more reasonable way to obtain corrosion current densities of rebar is combining EIS measurement with TPP measurement. Crack number shows the most significant effect on corrosion behavior of rebar, while crack spacing possesses the least one.

Natural Frequency Response Evaluation for RC Beams Affected by Steel Corrosion Using Acceleration Sensors

“…According to our previous studies [8,9], using the electrochemical test methods could measure the corrosion current densities of steel bar which embedded in concrete more exactly; by this, theoretical corrosion volume of steel bar could be obtained after measuring the corrosion current densities of steel bar by δ t = Mi corr t ρ s nF ,…”

“…Nowadays, engineers and researchers have recognized that steel corrosion is a major factor that deteriorates the durability of RC structures [3][4][5]. In the past, the method for corrosion assessment of steel bars embedded in the RC structure is destructive (such as the steel mass loss measurement after core sampling [6,7]), which is harmful and uneconomical to the RC structures [8,9]. This problem motivated the interest in utilizing nondestructive techniques for structural health monitoring; and the main purpose of structural health monitoring is to detect structural damage and reduce the risk of structural failure which may lead to casualties and property losses.…”

Life Cycle Cost Assessment of Preventive Strategies Applied to Prestressed Concrete Bridges Exposed to Chlorides

“…Although there are several mechanisms that may degrade concrete in severe environments, experience demonstrates that the most critical threat to concrete structures exposed to marine environments is chloride-induced corrosion of the reinforcing steel bars [3][4][5]. Research has been carried out on this specific mechanism for many years [6][7][8][9], leading to the development of different preventive measures to increase resistance to corrosion from the beginning of the structure life cycle, thus resulting in less maintenance-demanding solutions.…”

Application of Fuzzy and Rough Sets to Environmental Zonation for Concrete Durability: A Case Study of Shaanxi Province, China

“…Due to the various environmental conditions of concrete structures, the mechanism of durability deterioration is complex. For instance, carbonization [2], freeze-thaw damage [3][4][5], acid rain [6,7], and ion erosion [8][9][10][11][12] can directly affect the durability of concrete structures. It is necessary to take into account the in-service environmental condition when it comes to the design of new concrete structures and the evaluation and maintenance of existing concrete structures.…”