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The main purpose of this work is to develop a preliminary seismic assessment method for corroded low-rise reinforced concrete (RC) building structures. Additionally, the proposed method can be combined with the existing evaluation method of durability, which is used to determine the deterioration degrees of corroded RC members. In order to quantify the effect of corrosion on the ultimate shear strength of a corroded RC column, this work uses experimental data concerning corroded RC column members to verify models for predicting the mechanical behavior of a corroded RC member. Furthermore, based on the database of low-rise RC building structures in Taiwan, this work also proposes strength reduction factors for use in estimating the ultimate shear strength of corroded RC columns in a preliminary seismic assessment. Finally, this work takes two school buildings as in the case study to demonstrate the procedure for making a preliminary seismic assessment of corroded low-rise RC building structures. [ABSTRACT FROM AUTHOR]

The main purpose of this work is to develop a reliability analysis of concrete cover against the ingress of airborne chloride ions, and then to use it to determine the appropriate thicknesses of concrete cover or the water–cement or water–binder ratios of concrete (W/C or W/B) for meeting a reliability requirement. At first, for determining the corrosion occurrence time of reinforcing bars embedded in concrete, in addition to the one-dimensional diffusion model of chloride ions in concrete, a two-dimensional diffusion model for circular RC piers is developed. In order to be applicable in engineering practice, an amplification factor of chloride concentrations of the concrete surfaces is proposed to modify the one-dimensional diffusion model of chloride ions in concrete for considering the two-dimensional diffusion effect. In addition to Monte Carlo simulation (MCS), the first-order reliability method (FORM) and the moment method are used to calculate the reliability of concrete cover against the ingress of airborne chloride ions. Based on the comparison results of various reliability analysis methods, the third-moment reliability design procedure is selected to determine the appropriate thickness of concrete cover or, W/C or W/B of concrete for meeting a reliability requirement. [ABSTRACT FROM AUTHOR]

Static‐cyclic loading is used to identify the reduction factors of seismic capacity of damaged reinforced concrete (RC) column members. The reduction factors of seismic capacity that are obtained from specimens damaged under static‐cyclic loading differ from those obtained in dynamic testing, and this difference is investigated in this work. The experimental results obtained in this work, previously obtained results, and the "Pacific Earthquake Engineering Research Center Structural Performance Database (PEER)" are used to obtain reduction factors of strength, stiffness, and energy dissipation. From the damage levels of column members after an earthquake, corresponding reduction factors can be determined and used in the seismic assessment of an RC building. [ABSTRACT FROM AUTHOR]

In the displacement-based seismic design and evaluation, the equivalent linearization method is one of the approximation methods to estimate the maximum displacement response of a single-degree-of-freedom (SDOF) system. Based on the past research conducted by Okano & Miyamoto and the seismic design code in Taiwan, this work proposes modified equivalent linearization method (MELM) of a SDOF system for a mid-rise reinforced concrete (RC) building structure. By considering a modification factor suggested by the equivalent linear method proposed by Okano and Miyamoto and performing the nonlinear regression analysis, the accuracy of the proposed method can be improved. A total of 348 ground motions recorded on the various earthquakes are used to calculate error statistics of MELM. Additionally, a closed-form formula for the constant-damage ductility demand spectrum (CDDDS) that corresponds to a specified reliability is suggested in this work. [ABSTRACT FROM AUTHOR]