In this study, considering this construction process, the parametric study is performed and analyzed about factors affecting seismic analysis of cut-and-cover tunnel, such as analysis method(response displacement method, time history analysis method), surrounding soil(in-situ soil or refilled soils), refilled range(d). Consequently, it is hoped to provide the preliminary data for a better reasonable review on seismic design and seismic performance assessment of underground structures.

The seokbinggo structure has the load characteristics supporting the vertical load and lateral pressure. Also, the load transfer mechanism and stress concentration should be considered through the design variable analysis according to construction types of seokbinggo. To this end, this study performs the structural behavior evaluation of seokbinggo according to arched stone space.

In this study on the seismic behavior of the bridge that does not affect the safety of the range of variation of the length of the pier was looking for. The type of bridge is difficult to set clear standards for the geometric stiffness of the bridge, due to the diversity of soil conditions on the number of all cases. Thus, PSC girder and steel box girder bridge the representative of the highway bridge types were analyzed. Changes in the length of the pier ± 5% increments up to 20% were analyzed.

Steel Box-Truss Hybrid bridge consisted with steel box type in positive moment that is allowed to resist with low depth and truss type in negative moment not only has restriction of delivery but has to use high depth is new type bridge. In this study, structural analysis of Steel Box-Truss hybrid curved bridge with various curvature is performed and compared with member force and displacement of Steel Box-Truss Hybrid straight bridge. Also the applicable limited curvature of Steel Box-Truss Bridge form is proposed.

The innovative and environment-friendly tram vehicle and it’s trackway system are developed based on the government’s R&D funding. Accordingly, in order for the test drive of developed vehicle, a tram trackway as test-bed, is being constructed in Osong, where is located inside Korea Rail Network Authority in Chungcheongbuk-Do. In this paper, the construction method of trackway for wireless and low-floored tram vehicle is introduced for the first time in Korea.

This study proposes an advanced type of a micropile system. The proposed micropile system consists of perfobond ribs installed steel rod to improve shear capacity between the thread and the grout, and partially expanded drill holes to increase resistance capacity between the grout and the ground. This study contains experimental evaluations on the proposed micropile system to verify the load-carrying capacity of shear key created by the partially expanded drill hole. Through on-site pullout tests, it was found that load-carrying capacity increased significantly in the proposed micropile system, due to the shear keys created by the partially expanded drill hole.

In this study, a newly developed reinforced concrete (RC) composite column strengthened by high performance fiber reinforced composite (HPFC) was analyzed by using a nonlinear flexural analysis of columns. The analysis by the developed model was well predicted the experimental performances of HPFC and RC composite columns.

In this study, experimental research was carried out to study the structural performance of slab-column joints designed by the application of reducing of joint regions damage using steel fiber reinforced concrete. Test results showed that specimens(RCFPS series) were increased the maximum load-carrying capacity by 1.12~1.23 times and showed stable hysteresis behavior in comparison with the standard specimen(SRCFP).

An efficient and practical reliability analysis method is required for the development of reliability-based design (RBD) guidelines of coastal structures. Such a novel method is presented in this paper. It is capable of evaluating reliability of real complicated coastal structures considering uncertainties in various sources of design parameters. It is developed by intelligently integrating the Latin hypercube sampling (LHS) method and the finite element method (FEM). The applicability and efficiency of the proposed method are verified using a caisson-type quay wall. in the numerical example.

Construction period is one of the most important factors which influence on cost and quality in nuclear power plant construction. As part of continued efforts for the competent reactor type, an improved method for NSSS(Nuclear Steam Supply System)'s installation in the reactor containment building is developed to minimize the construction period. This study referred to knowledge and experiences from nuclear power plant constructions over 30 years. The proposed method can be applied to the APR+ in the near future.

This study deals with the structural method in conjunction with deep floor slab that can ensure a sufficient fire resistance capacity from the point of view of lateral side of structure configuration in which asymmetric H-beams are partially buried in the concrete slab. In addition, this method can maximize more the story height reduction effects of slim floor system, as its applied building is higher. Hence, this study analyses fire resistance based on KS F 2257-1, inspecting behavior and temperature property of the fire of slim floor system applied to asymmetric H - beam, by changing the cross-sectional shape of this.

To predict the size of fire in the building, it was conducted a real fire experiment with a manufactured mock-up that had unit block size of 2.44 (L) × 3.6 (W) × 2.4 (H) m. The real fire testing was proceeded under scenario in which the fire starts from trash and is spread to all of real inflammable materials put beforehand inside the unit block such as bed, wardrobe and chest of drawers. As a experimental result, the fire grew rapidly about 120 seconds after the ignition, whose maximum heat release rate was 2658.9 kW.

In this study, the fire test was performed under loading conditions, applied to a new concept reinforced fire protection that is suitable also to the reinforced concrete members by using the wire rope that can secure the lateral confinement of reinforcing bars, mixed with polypropylene fiber that is a reducing material of explosive fracture developed by the existing studies, steel fiber and hybrid fiber-cocktail in order to create a method to ensure the fire resistance efficiency for high-strength concrete of 60MPa. As a result of analysis, 60MPa strength concrete column recorded 146 minutes of fire-resistance performance under the hoop, and 180 minutes under wire the rope application.

Chloride binding capacity in cementitious materials is a crucial factor for service life prediction of marine concrete. C-S-H phase have significant physical binding capacity for chloride ions. In this study, specific surface area of C-S-H with various Ca/Si ratio was measured. This study suggested effective way to compute maximum adsorption of bound chloride by C-S-H based on theory single molecular layer. In addition, surface potential is very important as a main mechanism for chloride binding adsorption. Thus, intrinsic equilibrium constant was obtained and surface potential of C-S-H was calculated in chemical equilibrium solution by means of PHREEQC. Based on the experiment results, to develop integrated system for prediction of chloride binding behaviors is final goals.

This study is to propose a more reasonable durability prediction models about compression strength and carbonation of Seoul Metro. The Seoul Metro has been used more than 30 years and accumulated many diagnosis data for about fifteen years. As a result of the analysis of compressive strength and carbonation, we were able to draw prediction models with accuracy of more than 80% and confirmed the prediction model's reliability by comparing it with the existing models. We've also confirmed field suitability of the prediction models by applying field, the average error of an estimate on compressive strength and carbonation depth was about 20%, which showed an accuracy of more than 80%.

This study have interests in presenting the process of material optimization design. This study was designed by using design of experiment. To present the form of model and explore the optimal point of response surface model, central composite design(CCD) and Response Surface Methodology(RSM) were used in the design of the experiment and in the analysis of the results.

Concrete has been considered as a semi-permanent structural material in construction industry. However, durability of concrete member is affected by carbonation, chloride attack, and water, etc. Therefore, to avoid the deterioration of concrete surface treatment materials are applied. This study discusses the long-term performance and desirable quality of surface protection materials for expressway concrete structures.

Investigated the factors to effect on the flow of geopolymer mortar based on on ground granulated blast furnace slag in order to develop cementless alkali-activated concrete GGBS.

In this paper, to investigate the microstructural characteristics of MgO concrete according to cement manufactures, it was carried out XRD, SEM, DSC and Autoclave test. For two types of cement, the micro structural characteristics were observed by test variation of curing temperature and MgO mixing ratio until age 1 year. DSC was conducted with curing temperature of 20, 30, 40℃ and MgO mixing ratio of 0% and 5%. XRD and SEM were conducted with curing temperature of 20, 40℃ and MgO mixing ratio of 0% and 10%. Autoclave test was conducted with MgO mixing ratio of 0%, 3% and 5%.

In previous research, it was found that waste oil was effective on resisting carbonation of concrete. This study is to find the effect of waste oil on the fundamental properties of concrete when blast furnace slag with high volume is used as a partial replacement of cement. Test results showed that the addition of waste oil in the concretes decreased slump and air content, but further reduction was not observed as the amount of the waste oil further increased. In addition, the waste oil had a little impact on deteriorating the compressive strength of the concretes.