This study investigates structural behaviors such as ultimate strength and weld metal fracture mechanism of carbon steel (SS400) fillet-welded connections with shielded metal arc welding (SMAW) through monotonic tensile test. Specimens of TFW series (transverse fillet weld against loading direction) and LFW series (longitudinal fillet weld) failed by tensile fracture and shear fracture, respectively in the weld metal of connections. Test strengths of specimens were compared according to welding direction and weld length.

In reality, the mono-pile foundation system of OWT (Offshore Wind Turbine) can be damaged due to uncertainties and variations in both ocean environmental loadings and/or soil resistance around the foundation. In other words, the uncertainty parameters directly influence the safety, the performance and the structural behavior of a structure. In this study, a laterally loaded mono-pile foundation for OWT structure is considered to examine the degree of influence of uncertainties in the pile-soil system of the structure by an accurate and practical reliability assessment approach.

The purpose of this study is to investigate the bond characteristics of deformed steel bar for concrete with bamboo activated carbon. Pullout test was conducted for specimens with various replacement ratio (0%, 10%, 20%) of bamboo activated carbon. Test results show that it need to use a concrete with a replacement ratio of bamboo activated carbon of 10% or less to retain proper bond strength.

This study presents the fatigue performance of the mooring lines for submerged floating tunnels (SFTs), the new type transportation system for land connection. Because of the structural characteristics, the submerged structure is continuously affected by various environmental loadings such as wind, wave, and current. In general, waves are considered as one of the main external sources which induce dynamic behavior of the offshore floating structures. Therefore, fatigue damage and performance of the mooring lines should be evaluated based on their dynamic structural stress induced by the waves acting to the floating structures. In this study, fatigue damage and performance of the mooring lines for SFTs under severe wave conditions are analyzed using hydrodynamic analysis, Rainflow counting method, and Miner’s rule for obtaining dynamic stresses, treating the fluctuating stresses, and calculating the fatigue damage index, respectively.

Finite Element Model(FEM) is generally used for evaluating a bridge construction. But it has discrepancy between measured data of real structure and analysis value of FEM. Therefore, FEM has to reflect characteristics of real structure using FEM updating. Static and dynamic data used to FEM updating update different characteristic of FEM. However, since it is difficult to measure static data, static information extracted from dynamic measured data can be used. In this study, new concept, LDFAC, using Lateral Distribution Factor(LDF) extracted from dynamic data is introduced as static information. As the analysis results, it is verified to get more accurate updating value when updating FEM with LDFAC.

In This study, the bio-inspired high energy absorption cementitious composites was developed which is a new structural material performing a high energy absorption and ductility property imitated from shells. The flexural performance of the cementitious composites was evaluated and as a result, excellent ductility was obtained.

In this paper, the finite element model updating method of the PSC bridge based on the static and dynamic data is verified through field experiment. The proposed method consists of two steps. First, update the rotational stiffness of the supports using the deflection and rotational displacement measurements that occur when the moving loads pass through the bridge. The stiffness of each member is updated by using the dynamic characteristics estimated from the acceleration measured by the ambient vibration test. The finite element model updated by the proposed method can predict the static and dynamic behavior of actual bridges through field experiment.

In recent years, non-welded building hardware that can be installed by bolt assembly is used, which does not require fire prevention related materials, fire fighting equipment and personnel. However, there is a need for a method to compensate for the occurrence of buckling at the bolted portion at the time of construction.The purpose of this study is to evaluate the behavior of joints that can control the sliding between members by using anti slip brackets.

Due to frequent localized torrential downpours caused by environmental contamination, collapses of retaining wall structure have increased, so that it is required to enhance structural strongness. This research focuses on the stability and effectiveness of the soil-nailed natural surface(SNS)”method, which is eco-friendly and functions as retaining wall structure.

The non-welded building hardware method can reduce accidents caused by welding, and can be constructed by bolt assembly, which can reduce labor costs and shorten the construction period. This study is to compare and verify the performance according to the location where the brackets are joined to the joints using the non-welded building hardware method

In this study, to examine the application of strut of high strength concrete, an parameter study was performed. High strength concrete has high capacity for the strut member, especially 80MPa concrete strut has equal quality to 40MPa concrete strut with FRP. Also it is insignificant that the difference of member force between variation in boundary condition on the strut of PSC Box Girder.

In this study, the 3 point bending tests were conducted to evaluate ductility capacity of splice rebar. As a result, the difference in ductility between RC members embedded in the coupler and general RC members was not significant. For more accurate analysis, 4 point bending tests are considered to be necessary.

In this study, the 1-directional tension tests were conducted to evaluate ductility capacity of splice rebar. As a result, the ductility of the reinforced concrete members embedded in the coupler was significantly lower than that of general RC members.

In this current study evaluated the horizontal shear strength of reinforced concrete pile between pile body and infilled concrete interface. From the calculated results of horizontal shear strength it was found that the interface between pile body and infilled concrete was evaluated to be able to safely resist factored shear stress.

In this study, the artificial neural network (ANN) based estimation method for rotational stiffness of column-beam connection in steel moment frames is presented. Three story and one bay steel moment frame is used as the example structure. Natural periods and mode-shapes are used as the input data and the rotational stiffness values of connections are used as the output data.

Studies on the lattice girder of the cross sectional form and construction works through laboratory experiments have been performed. The numerical analysis for structural behavior such as deflection and stresses on the lattice girder, however, are insufficient. In this study the stiffness of a lattice girder was examined by using MIDAS.

In this study, the shake table test of the damaged reinforced concrete frame was carried out and the damage and dynamic response characteristics were evaluated. The static lateral-cyclic test for the specimen was followed by the dynamic test. As a result of the shake table test, damage was concentrated on existing cracks and the maximum inter-story drift ratio was calculated as 1.94% at the final excitation step.

Current design code provisions suggest calculation method for slab-column joint concrete compressive strength. Because equation for slab-column joint compressive strength only consider the compressive strength of column and slab concrete, they are relatively conservative than the results of experimental researches. In this study, calculation method for slab-column joint strength which consider confinement effect of concrete are suggested. Suggested calculation procedure and results were compared with test results of previous researches.