Jung-Sik Kong

Durability Prediction for Concrete Structures Exposed to Chloride Attack Using a Bayesian Approach

Dept. of Civil & Environmental and Architectural Engineering, Korea University, Seoul 136-713, KoreaABSTRACT This paper provides a new approach for predicting the corrosion resistivity of reinforced concrete structuresexposed to chloride attack. In this method, the prediction can be updated successively by a Bayesian theory when additional dataare available. The stochastic properties of model parameters are explicitly taken into account into the model. To simplify the pro-cedure of the model, the probability of the durability limit is determined from the samples obtained from the Latin hypercube sam-pling technique. The new method may be very useful in designing important concrete structures and help to predict the remainingservice life of existing concrete structures which have been monitored.Keywords : corrosion, bayesian theory, durability prediction, remaining service life, monitoring.

A Development of Quantitative Analysis Model for the Policy Analysis in Feasibility Study Using the Performance Assessment Method

As an impactive factor on industries and national economy, The Social Overhead Capital(SOC) is major factor to determine the national competitiveness and the investment of SOC is essential for its economic growth. Accordingly, introduction of the preliminary feasibility study and establishment of legal institutionalization and evaluation system has been carried out and reviewed since 1999. Nevertheless of these efforts, basic problems such as lack of scientific method for investment evaluation and loss of effectiveness on feasibility studies are continuously being brought up. Moreover, as the preliminary study to improve the mentioned problems is mainly focused on the economic and estimated demand analysis, the study of policy analysis, the most important phase during a feasibility study, is still insufficient. Therefore, in this paper, a quantitative decision-making model, to which the performance assessment method of Value Engineering(VE) is applied, is developed and proposed to improve the policy analysis of (preliminary) feasibility study that requires combining with relative studies, to induce quantitative analysis method, and to contribute the improvement of value on the political aspect for SOC investment goals and use as a strategic decision-making method by systematic analysis.

Development of a Successive LCC Model for Marine RC Structures Exposed to Chloride Attack on the Basis of Bayesian Approach

Dept. of Civil & Environmental and Architectural Engineering, Korea University, Seoul 136-713, KoreaABSTRACT A new life-cycle cost (LCC) evaluation scheme for marine reinforced concrete structures is proposed. In thismethod, unlike the conventional life-cycle cost evaluation performed during the design process, the life-cycle cost is updated suc-cessively whenever new information of the chloride penetration is available. This updating is performed based on the Bayesianapproach. For important structures, information required for this new method can be obtained without any difficulties because itis a common element of various types of monitoring systems. Using the new method, the life-cycle maintenance cost of structurescan be estimated with a good precision.Keywords : LCC, chloride penetration, bayesian approach, monitoring

Structural Performance Analysis of New Type CFTA Girder Bridge

In this research, static load test is performed to verify the arch effect and structural performance of CFTA(Concrete-Filled and Tied steel tubular Arch) girder, and FE(Finite Element) analysis is performed to investigate validity of the test result. CFTA girder is designed to maximize the benefit of each material, such as steel plate, filled concrete and PS tendon. Static load test is performed based on the frame-analysis result of 12m sample miniature model. The result of static load test is that structural performance and safety of CFTA girder are confirmed and there is different deflection mode with other structural form result from arch effect. FE analysis with ABAQUS is also performed to show the validity of the truck collision safety and static load test.