This study aims to apply homotopy method to space truss composed of discrete members to obtain a semi-analytical solution. For the purpose of this research, a nonlinear governing equation of the structures is formulated in consideration of geometrical nonlinearity, and homotopy equation is derived. The result of carring out dynamic analysis on a simple model is compared to a numerical method of 4th order Runge-Kutta method(RK4).

In this study, trapezoidal corrugate plate were subjected to cyclic loading under displacement control. And then, results from the experiment, the behavioral characteristics and mechanism of energy dissipation were investigated. This result were different to the cumulative size of energy dissipation capacity in load-displacement curve. Based on these results, Influence of the shape is very large and it is determined the define an appropriate shape for the size.

A corrugated steel culvert is well used as underpass structure because of its advantages. But many deformed culverts were observed recently. In this paper, we analyzed structural safety of this culvert using 3D laser scanning geometry data, which is called point cloud data. All surface geometry can be built and transformed into the analysis model based on actual geometrical conditions from this data.

This study investigated the flexural performance of high performance fiber reinforced cementitious composite (HPFRCC), which used high strength steel fibers with volume fraction 8%. Under the third-point loading using a closed-loop, servo-controlled testing system (ASTM 1609), load-deflection curves were obtained. The major test variables include silica fume replacement ratio 15% and exposure termperature, ambient and 400°C. The flexural strength was similar to the compressive strength and the absorbed fracture energy was relatively greater than other typical HPFRCC materials. This may be a composite reaction of the strong bonding between steel fiber and matrix and high compressive strength of the matrix itself. Once the specimens were exposed to high temperature 400°C the flexural strength decreased.

In this paper, the buckling analysis was performed to compare the buckling mode and the buckling load for siffened plates having ㄷ, Reverse T, corrugated wave, ㄹ, honeycomb and ㅁ types of ribs. In the case of the rib space S=300mm, various types of buckling modes were appeared according to the rib types. In the case of the rib space S=450 and 600mm, the buckling loads of ㄹ, ㅁ and honeycomb were bigger than that of ㄷ and ㅁ type was the biggest.

Regarding deck replacement of bridge structures, it is important to minimize total construction time and costs ensuring safety of it. Since cast-in-place concrete deck takes a long time for replacement, precast concrete deck system is considered as an effective alternative. Structural performance, economic feasibiltity and constructability of precast deck system are mostly affected by joint properties between precast deck panels. To improve the joint properties, this research presents a new precast deck system of ribbed section joint with protruding lower concrete and verifies tits applicability through parameter tests.

The volume expansion of corroded steel reinforcement produces tensile stress on the surrounding concrete, which causes splitting cracking of concrete cover, and deteriorates the service ability and durability of reinforced concrete(RC) members. In addition, since the steel corrosion induces bond strength degradation between steel bar and concrete, the structural performance of RC members can be deteriorated significantly. In this study, the theoretical study was performed to probe the mechanism of the bond strength reduction due to steel corrosion. The bond strength between corroded steel bar and concrete was calculated by mathematically formulating the expansion pressure of corroded steel reinforcement. The proposed model was verified by comparing with the existing test results, and it showed that the proposed model estimate the bond strength reduction of corroded RC elements very closely.

In this paper, 30 years of aged bridge in service used external post-tendons method flexural strengthening, was carried out the loading test and structural analysis in order to verify the performance improvement effect before and after strengthening. This experimental test results will be improvement of load carrying capacity for aged bridges

This study aims to verify the method of calculating blast load making similar damage from impact loading. In this process, LS-DYNA is used for modeling beam blast test. From the analysis, the max deflection of impact test and blast analysis is similar, so this method is verified.

In the both loading test results and analytical results of specimens with tapered threaded splices, the good agreement of load-carrying capacity are shown. Therefore the proposed model for tapered threaded splices can be applied to the analysis of structure with tapered threaded splices.

Probabilistic risk of an offshore wind turbine tower-monopile foundation structure is investigated using in this paper. It can consider both soil-structure-fluid coupled effect in the system and a large amount of variability in both ocean environmental load and soil resistance.

Recently, Korea Bridge Design Code(KBDC) adapts to the Limit State Design method(L.S.D) in 2012 according to the liberalization of construction market and the flow of international standardization of the design criteria. However, Korea Infrastructure’s Safety Inspection Guideline(KISIG) are still following the bridge safety evaluation applying the A.S.D and U.S.D methods. In this study, introduction of PSC bridge safety evaluation with L.S.D considered the traditional safety evaluation compared to the ASD and USD methods.

This paper carried out a study on design for the deviation block of PSC box girder bridges with external tendons. As a result, the actual load distribution on deviation block must be considered for design because of a discordance with the design concept.

This study reviews past literatures relevant to concrete beams using recycled aggregates (RAs) and investigate existing shear design equations for reinforced concrete (RC) beams. Then, a simplified, emprical design equation to determine the shear strength of high strength RC beams with RAs is proposed and compared with existing equations. The analysis indicated that the proposed equation provided the most accurate estimated of strength of high strength concrete beams with RAs.

Because significant difference between normal concrete and fiber reinforced ultra-high strength concrete under tension and compression, bond behavior also have significant difference. Based on the finite element analysis of bond test specimens, crack initiation and propagation process were investigated. Analysis results have been validated with test results and crack initiation stress was investigated.

The objective of this study is to evaluate the location of a failure surface generatrix and the punching shear strength of hollow plat slabs. The main test parameters was the location of a starting position of hollow materials that varied between 1d and 3d, where d is effective depth of slab section. Based on test results, the starting position of hollow materials in plat slabs is recommended to be more than 2d to avoid the reduction of concrete punching shear strength.

This study analytically reviewed the dissipated energy and ductility of Steel Plate Concrete (SC) walls subjected to cyclic shear forces to investigate the effects of shape and arrangement spacing of studs on the design of SC walls. As the decrease of stud spacings, the cumulative dissipate energy was increased and the seismic performance was improved. Under the same cumulative dissipate energy, the ductility was increased as the increase of stud spacings and the influences with stud type was insignificant.

The protective cover system is needed for the safety and bearing capacity of underground cable pipe. This study evaluates the flexural capacity through the experimental study according to the several design variables for the protective covers.

Finite element analysis is conducted for investigation of structure behavior of high strength concrete(HSC) column-normal strength concrete(NSC) slab connection according to aspect ratio(h/c). Analysis method is verified through comparison of experiment and analysis. As a result, regarding to the aspect ratio, the ultimate strength of column-slab connection decreased as the column dimension increased while the slab thickness did not influence on the ultimate strength of the connection.

We have experienced cracking around column bottom and safety check places on a bridge due to lamp post shaken by traffic and wind. So we need to take a measure to decrease stress on lamp post by suppressing vibration. In this study, We have tested how much we can reduce the stress by using an anti vibration damper.