• Proceeding of KASS Symposium
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• 2008.05a
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• pp.133-138
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• 2008

In this study, the seismic behavior of arch structure with lead rubber bearing(LRB) is analyzed. The arch structure is the simplest structure and has the basic dynamic characteristics among large spatial structures. Also, Large spatial structures have large vertical response by horizontal seismic vibration, unlike seismic behavior of normal rahmen structures. When horizontal seismic load is applied to the large spatial structure with isolation systems, the horizontal acceleration response of the large spatial structure is reduced and the vertical seismic response is remarkably reduced.

• Journal of the Korean Society of Hazard Mitigation
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• v.1 no.1 s.1
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• pp.81-90
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• 2001

This paper presents the results of the parametric study on the longitudinal behavior of 2-span continuous railway bridge. To perform the main objective of this paper, the effects of pier shaft stiffness, pier height, the size of pier foundation, and the bearing stiffness on the longitudinal behavior of the bridges are studied. Within the limits of this study, the research result has revealed that the variation of the fixed pier is more effective than that of the moved pier. In addition, the control of the hearing stiffness is much less expensive than that of any other parameters.

• Journal of the Earthquake Engineering Society of Korea
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• v.27 no.4
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• pp.181-186
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• 2023

In this study, considering the expansion/contraction behavior of the upper structure at all times and the abnormal behavior of the receiving friction elements that allow horizontal movement during earthquakes, a port receiving test body simulating the protrusion of the friction elements was created and the modulus performance was evaluated. In order to confirm the influence of the friction element's projection, the friction element's degree of separation was divided into four stages, and the shear behavior of the test specimen and the friction coefficient were confirmed. As a result of the experiment, it was found that the friction load increases as the protrusion degree of the friction element increases. On the other hand, as the degree of protrusion of the coefficient of friction increases, the coefficient of friction also increases. It was confirmed that damage to the friction elements during use increases the coefficient of friction, hinders smooth expansion and contraction of the upper structure, and causes stress concentration at the fixed-end support.

• Steel and Composite Structures
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• v.46 no.6
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• pp.745-757
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• 2023

In order to study the fatigue performance of the flat steel plate-lightweight aggregate concrete hollow composite bridge slab subjected to fatigue load, both static test on two specimens and fatigue test on six specimens were conducted. The effects of the arrangement of the steel pipes, the amplitude of the fatigue load and the upper limit as well as lower limit of fatigue load on failure performance were investigated. Besides, for specimens in fatigue test, strains of the concrete, residual deflection, bending stiffness, residual bearing capacity and dynamic response were analyzed. Test results showed that the specimens failed in the fracture of the bottom flat steel plate regardless of the arrangement of the steel pipes. Moreover, the fatigue loading cycles of composite slab were mainly controlled by the amplitude of the fatigue load, but the influences of upper limit and lower limit of fatigue load on fatigue life was slight. The fatigue life of the composite bridge slabs can be determined by the fatigue strength of bottom flat steel plate, which can be calculated by the method of allowable stress amplitude in steel structure design code.

• Structural Engineering and Mechanics
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• v.55 no.3
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• pp.461-472
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• 2015

The existence of initial imperfections in manufacturing or assembly of double-layer space structures having hundreds or thousands of members is inevitable. Many of the imperfections, such as the initial curvature of the members and residual stresses in members, are all random in nature. In this paper, the probabilistic effect of initial curvature imperfections in the load bearing capacity of double-layer grid space structures with different types of supports have been investigated. First, for the initial curvature imperfection of each member, a random number is generated from a gamma distribution. Then, by employing the same probabilistic model, the imperfections are randomly distributed amongst the members of the structure. Afterwards, the collapse behavior and the ultimate bearing capacity of the structure are determined by using nonlinear push down analysis and this procedure is frequently repeated. Ultimately, based on the maximum values of bearing capacity acquired from the analysis of different samples, structure's reliability is obtained by using Monte Carlo simulation method. The results show the sensitivity of the collapse behavior of double-layer grid space structures to the random distribution of initial imperfections and supports type.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.210-221
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• 2009

A new foundation type which is called Top-Base method has been used frequently in engineering practices in Korea. In this study, the settlement behavior of concrete Top-Base foundation on soft ground is investigated since the consolidation settlement of the embedding depth and the effect of footing dimensions are not included in current Korean criterion (2007). To obtain detailed information, the model tests of the Top-Base foundation are performed using the PLAXIS 3D finite element analysis. It is shown that in-situ measurements and finite element analysis of the behavior of foundations indicate that consolidation settlement is reduced up and bearing capacity of the foundation increases up to 50%~100%, compared to the primary non-treated ground. Based on this study, it is found that the Top-Base foundation prevents the lateral deformation of soft ground and reduces its negative dilatancy to the surface settlement, and that the foundation creates rather uniform stress distribution under it to increase its bearing capacity. It is also found that the total settlement of Top-Base foundation was highly dependent on the consolidation settlement and footing configurations.

• Structural Engineering and Mechanics
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• v.74 no.1
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• pp.145-156
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• 2020

There are separate merits and demerits to wood and steel. The combination of wood and steel as a compound section is able to improve the properties of both and ultimately increase their final bearing capacity. The composite cross-section made of steel and wood has higher hardness while showing more ductility and the local buckling of steel is delayed or completely prevented. The purpose of this study is to investigate the behavior of composite columns enclosed in wooden logs and the hollow sections of steel that will be examined in a laboratory environment under the axial load to determine the final bearing capacity and sample deformation. In terms of methodology, steel sheet and carbon fiber reinforced polymer sheet (FRP) are tested to construct hollow rectangular sections and reinforce timber. Besides, the method of connecting hollow sections and timber including glue and screw has been also investigated. As a result, timber lumber enclosed with carbon fiber-reinforced polymer sheets in which fibers are horizontally located at 90° are more resistant with better ductility.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3599-3609
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• 2010

Recently, the construction of coastal structures and high-rise structures against the horizontal and uplift forces increases with the developing the coastal developments. Especially the application of belled tension pile as foundation type to effectively resist uplift force is increasing in coastal structures. However, research on pullout resistance of belled tension pile has been limited and not yet been fully performed. Therefore, the pullout load tests of belled tension piles in four overseas sites were performed, then the bearing capacity, characteristics on load-displacement of piles and load distribution considering skin friction were investigated in this paper. In addition, the limit pullout bearing capacity calculated by the three-dimensional finite element analysis and theoretical methods were compared with values of in-situ test.

• Structural Engineering and Mechanics
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• v.52 no.3
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• pp.507-523
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• 2014

Shell foundations have been employed as an alternative for the conventional flat shallow foundations and have proven to provide economical advantage. They have shown considerably improved performance in terms of ultimate capacity and settlement characteristics. However, despite conical shell foundations are frequently used in industry, the theoretical solutions for bearing capacity of these footings are available for only triangular shell strip foundations. The benefits in design aspects can be achieved through theoretical solutions considering shell geometry. The engineering behavior of a conical shell foundation on mixed soils was investigated experimentally and theoretically in this study. The failure mechanism was obtained by conducting laboratory model tests. Based on that, the theoretical solution of bearing capacity was developed and validated with experimental results, in terms of the internal angle of the cone. In comparison to the circular flat foundation, the results show 15% increase of ultimate load and 51% decrease of settlement at an angle of intersection of $120^{\circ}$. Based on the results, the design chart of modified bearing capacity coefficients for conical shell foundation is proposed.

• Journal of the Korean Geotechnical Society
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• v.15 no.1
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• pp.79-98
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• 1999

In the present study, a simple finite element method of analysis to predict non-uniform settlements at the interface between the mat foundation and foundation soils is proposed. Based on the proposed finite element method of analysis, the method to evaluate load sharing ratios of the foundation soils adjacent to the granular group piles is also presented. Further proposed is a procedure to estimate ultimate bearing capacity of the skirted granular group piles in a square pattern. To verify validity of the proposed methods and the estimated ultimate bearing capacity of the skirted group piles, comparisons are made with the results analyzed by using the PENTAGON3D FEM program. Finally, behavior characteristics with different reinforcement patterns of the skirts and the effect of an increase of ultimate bearing capacity due to the skirts are analyzed in connection with the design parameters.