The Experts below are selected from a list of 48873 Experts worldwide ranked by ideXlab platform

I Petrelazar - One of the best experts on this subject based on the ideXlab platform.

  • corrosion damage diagnosis of a reinforced Concrete Beam after 40 years natural exposure in marine environment
    Cement and Concrete Research, 2006
    Co-Authors: O Poupard, V Lhostis, S Catinaud, I Petrelazar
    Abstract:

    Abstract A detailed investigation of the chloride induced corrosion damage was performed on a 40 years old reinforced Concrete Beam exposed in marine environment. Visual observations, electrochemical measurements, carbonation depth, total chloride content were carried out. Half-cell potential measurements were used to locate corrosion areas. It appeared that the interpretation based on gradient of the potential was in good concordance with real state of damage. Complementary destructive methods are applied to observe the real corrosion state of steel rebars and characterize the corrosion products and the steel/Concrete interface (optical and electronical microscopy tools (XRD, SEM, EDS and μ-Raman). All these data indicate that on the Beam, one may distinguish two types of areas: “high-corrosion zones” and “low-corrosion zones.” Given the fact that the “high corrosion zones” were found to be close to corrosion induced cracks and that they have a different morphology, this contribution concludes that the position of these areas did not shift in time.

  • corrosion damage diagnosis of a reinforced Concrete Beam after 40 years natural exposure in marine environment
    Cement and Concrete Research, 2006
    Co-Authors: O Poupard, V Lhostis, S Catinaud, I Petrelazar
    Abstract:

    Abstract A detailed investigation of the chloride induced corrosion damage was performed on a 40 years old reinforced Concrete Beam exposed in marine environment. Visual observations, electrochemical measurements, carbonation depth, total chloride content were carried out. Half-cell potential measurements were used to locate corrosion areas. It appeared that the interpretation based on gradient of the potential was in good concordance with real state of damage. Complementary destructive methods are applied to observe the real corrosion state of steel rebars and characterize the corrosion products and the steel/Concrete interface (optical and electronical microscopy tools (XRD, SEM, EDS and μ-Raman). All these data indicate that on the Beam, one may distinguish two types of areas: “high-corrosion zones” and “low-corrosion zones.” Given the fact that the “high corrosion zones” were found to be close to corrosion induced cracks and that they have a different morphology, this contribution concludes that the position of these areas did not shift in time.

Guido De Roeck - One of the best experts on this subject based on the ideXlab platform.

  • system identification and damage detection of a prestressed Concrete Beam
    Journal of Structural Engineering-asce, 2006
    Co-Authors: Joerg F Unger, Anne Teughels, Guido De Roeck
    Abstract:

    In the domain of civil engineering it is often necessary to monitor constructions such as buildings or bridges to maintain safety conditions. Nondestructive test methods outmatch other methods, because they do not influence the constructions performance. One approach is based on the experimental determination of modal parameters (eigenvalues, damping, mode shapes). From the changes in modal data damage can be detected. By updating a reference finite-element model such that its numerical modal data correspond well with the experimental modal data of the damaged structure, the damage pattern can be identified. When applying this technique to prestressed Concrete, the problem arises that, because of the prestressing, cracks close again. Therefore a research program was started to investigate the change of modal parameters of a gradually damaged prestressed Concrete Beam. Static loads with increasing amplitude were applied. In between each load step a dynamic measurement was performed. The results show that the damage detection remains difficult for prestressed Concrete in the early damage state. However, a damage pattern could be identified, which corresponds to the locations of the final failure.

O Poupard - One of the best experts on this subject based on the ideXlab platform.

  • corrosion damage diagnosis of a reinforced Concrete Beam after 40 years natural exposure in marine environment
    Cement and Concrete Research, 2006
    Co-Authors: O Poupard, V Lhostis, S Catinaud, I Petrelazar
    Abstract:

    Abstract A detailed investigation of the chloride induced corrosion damage was performed on a 40 years old reinforced Concrete Beam exposed in marine environment. Visual observations, electrochemical measurements, carbonation depth, total chloride content were carried out. Half-cell potential measurements were used to locate corrosion areas. It appeared that the interpretation based on gradient of the potential was in good concordance with real state of damage. Complementary destructive methods are applied to observe the real corrosion state of steel rebars and characterize the corrosion products and the steel/Concrete interface (optical and electronical microscopy tools (XRD, SEM, EDS and μ-Raman). All these data indicate that on the Beam, one may distinguish two types of areas: “high-corrosion zones” and “low-corrosion zones.” Given the fact that the “high corrosion zones” were found to be close to corrosion induced cracks and that they have a different morphology, this contribution concludes that the position of these areas did not shift in time.

  • corrosion damage diagnosis of a reinforced Concrete Beam after 40 years natural exposure in marine environment
    Cement and Concrete Research, 2006
    Co-Authors: O Poupard, V Lhostis, S Catinaud, I Petrelazar
    Abstract:

    Abstract A detailed investigation of the chloride induced corrosion damage was performed on a 40 years old reinforced Concrete Beam exposed in marine environment. Visual observations, electrochemical measurements, carbonation depth, total chloride content were carried out. Half-cell potential measurements were used to locate corrosion areas. It appeared that the interpretation based on gradient of the potential was in good concordance with real state of damage. Complementary destructive methods are applied to observe the real corrosion state of steel rebars and characterize the corrosion products and the steel/Concrete interface (optical and electronical microscopy tools (XRD, SEM, EDS and μ-Raman). All these data indicate that on the Beam, one may distinguish two types of areas: “high-corrosion zones” and “low-corrosion zones.” Given the fact that the “high corrosion zones” were found to be close to corrosion induced cracks and that they have a different morphology, this contribution concludes that the position of these areas did not shift in time.

Mohammed Sheroz Khan - One of the best experts on this subject based on the ideXlab platform.

  • Deflection behavior of a prestressed Concrete Beam reinforced with carbon fibers at elevated temperatures
    Frontiers of Structural and Civil Engineering, 2019
    Co-Authors: Mohammed Faruqi, Mohammed Sheroz Khan
    Abstract:

    Fiber reinforced polymer(FRP) have unique advantages like high strength to weight ratio, excellent corrosion resistance, improving deformability and cost effectiveness. These advantages have gained wide acceptance in civil engineering applications. FRP tendons for prestressing applications are emerging as one of the most promising technologies in the civil engineering industry. However, the behavior of such members under the influence of elevated temperatures is still unknown. The knowledge and application of this could lead to a cost effective and practical considerations in fire safety design. Therefore, this study examines the deflection behavior of the carbon fiber reinforced polymer(CFRP) prestressed Concrete Beam at elevated temperatures. In this article, an analytical model is developed which integrates the temperature dependent changes of effective modulus of FRP in predicting the deflection behavior of CFRP prestressed Concrete Beams within the range of practical temperatures. This model is compared with a finite element mode (FEM) of a simply supported Concrete Beam prestressed with CFRP subjected to practical elevated temperatures. In addition, comparison is also made with an indirect reference to the real behavior of the material. The results of the model correlated reasonably with the finite element model and the real behavior. Finally, a practical application is provided.

Chuanqing Fu - One of the best experts on this subject based on the ideXlab platform.

  • corrosion characteristics of a 4 year naturally corroded reinforced Concrete Beam with load induced transverse cracks
    Corrosion Science, 2017
    Co-Authors: Chuanqing Fu, Hailong Ye
    Abstract:

    Abstract This work studies the corrosion characteristics of reinforcement in a 4-year naturally corroded Concrete Beam after accelerated chloride penetration. The results show that the presence of transverse cracks in the tension surface of reinforced Concrete Beam can globally exacerbate the loss of cross-sectional area of rebar. However, there is no strong correlation between the width of transverse cracks, with the width of longitudinal cracks and loss of cross-sectional area of corroded rebar at a specific location. The self-healing of cracks and sacrificing roles of stirrups at crack tips seem to reduce the impacts of cracks on the corrosion propagation.