Concrete cylinder piles produced by a centrifugally cast, vibrated, roller-compacted process have shown promising corrosion resistance in marine environments. Three bridges in the Florida panhandle with ~40 years in aggressive marine service and one newly constructed marine bridge utilizing concrete cylinder piles were examined. Examination of the older marine bridges showed minimal corrosion d...

The paper presents a new analytical model to study the evolution of radial cracking around a corroding steel reinforcement bar embedded in concrete. The concrete cover for the corroding rebar is modelled as a thick-walled cylinder subject to axisymmetrical displacement constraint at the internal boundary generated by expansive corrosion products. A bilinear softening curve reflecting realistic ...

In this paper, a novel kind of method to monitor corrosion expansion of steel rebars in steel reinforced concrete structures named fiber optic coil winding method is proposed, discussed and tested. It is based on the fiber optical Brillouin sensing technique. Firstly, a strain calibration experiment is designed and conducted to obtain the strain coefficient of single mode fiber optics. Results ...

This study focused on the residual strengths of reinforced concrete beams with heavy deterioration. This work is based on experimental investigation of reinforced concrete beams naturally corroded over 30 years. Visual inspection was firstly conducted and the concrete cracking, spalling of concrete cover, corrosion of rebar were recorded. Material tests on concrete and corroded rebar were also ...

Corrosion of concrete reinforcement members has been recognized as a predominant structural deterioration mechanism for steel reinforced concrete structures. Many corrosion detection techniques have been developed for reinforced concrete structures, but a dependable one is more than desired. Acoustic emission technique and fiber optic sensing have emerged as new tools in the field of structural...

Corrosion of steel reinforcement in concrete structures and bridges is a major problem facing the departments of transportation worldwide. In the United States, maintenance and replacement costs are measured in billions of dollars. Salt environment in hot climate and the use of deicing salts in cold regions have resulted in steady deterioration of bridge decks due to corrosion. These concerns h...

Expansion and cracking induced by the corrosion of reinforcement concrete is the major factor in the failure of concrete durability. Therefore, monitoring of concrete cracking is critical for evaluating the safety of concrete structures. In this paper, we introduce a novel monitoring method combining Brillouin optical time domain analysis (BOTDA) and fiber Bragg grating (FBG), based on mechanic...

IN TR O D U CTIO N -TH E PROBLEM A few years ago a problem that previously had been a modest highway maintenance concern suddenly became a major source of dif­ ficulty and expense to highway departments in many areas of the coun­ try; including Indiana. In brief, concrete bridge decks, some new, started to spall, then delaminate, then come apart in relatively large chunks. The problem was quick...

The corrosion and protection behaviour of mild steel embedded in concrete, and partially immersed in 3.5% sodium chloride solution, was studied in this investigation at ambient temperature by potential monitoring technique. The work was performed with a digital multimeter and a Cu/CuSO4 electrode (CSE) as the reference electrode. Extracts of pawpaw (carica papaya) leaves and sodium nitrite in d...

The damage evolution of concrete subjected to drying-wetting cycles in different concentration of sodium sulfate solution was investigated based on micro and macro-observations. Through the experiment, weight loss, compressive strength loss and the damage layer thickness of concrete were measured after different drying-wetting cycles. The mechanical properties degradation in the damage layer of...