Bond Deterioration of Corroded-Damaged Reinforced Concrete Structures Exposed to Severe Aggressive Marine Environment

Abstract

Cracks lead to a reduction of the bond between concrete and reinforcing steel rebars. A considerable decrease in the bond strength is more dangerous to a structural element’s safety than the loss of the cross-sectional steel reinforcement area. The purpose of this study is to evaluate the bond strength of corroded-damaged structures exposed to severely aggressive marine environments. Eighteen (18) cube specimens with dimensions of 200 mm x 200 mm were cast. They were reinforced with three (3) different diameters of deformed steel and were grouped as unconfined and confined. The specimen was accelerated under a simulated corrosive environment. The experiment results reveal that the bond strength of concrete and steel reinforcement is susceptible to corrosion levels. The degree of corrosion significantly affects the bond strength of concrete and steel. The bond strength and the average crack width have a strong correlation; a minimal amount of corrosion with a minimum crack width of 0.03 mm after cracking reduces the bond strength to an unacceptable level. Stirrups confinement has a significant influence on the bond strength; it provides an excellent means to counteract bond loss. The loss of bond directly affects the serviceability and ultimate strength of reinforced concrete structures. There is an exponential relationship between cement and steel reinforcement’s bond strength with the serviceability and residual strength of reinforced concrete structures.

Assessment and Evaluation of Blended Cement Using Bamboo Leaf Ash BLASH Against Corrosion

“…As shown in Figure 12, mixtures of cement with more than 10% bamboo leaf ash content are more prone to deterioration because they have wider crack widths. Furthermore, according to Dacuan and Abellana (2021), the width of the crack due to corrosion has a linear correlation with the corrosion level. High corrosion levels lead to a significant amount of rust products that push the surface of the concrete, resulting in wider cracks on its surface [9].…”

“…According to Dacuan and Abellana (2021), the corrosion of steel reinforcement leads to a reduction in the bond strength between the steel and concrete interface [9]. However, it is a blended mixture of concrete that provides significant protection to the steel reinforcement and maintains the bond strength between the surfaces of two materials, steel and concrete elements.…”

“…Thus, it is noted that the interaction between the type of material and environmental exposure affects the deterioration of all structures [8]. Among the deterioration, corrosion of steel reinforcement due to chloride intrusion in concrete structures is the root cause of the deterioration problem of most structures located in coastal areas [2,9]. Corrosion of steel reinforcement, particularly in coastal areas, is a severe problem, and its prediction of occurrence is essential for structural and material engineers [10].…”

Effect of Cathodic Protection on Reinforced Concrete with Fly Ash Using Electrochemical Noise

“…In the construction industry, corrosion of steel reinforcement is one of the main issues. It is considered the leading cause of the premature deterioration of reinforced concrete structures [ 1 , 2 , 3 ]. The most predominant factors affecting the steel bars can be physical, mechanical, biological, or chemical [ 4 , 5 ].…”