Using the wave forces obtained from ANSYS AQWA, the structural analysis of the gravity substructure for 5MW offshore wind turbines is carried out through ANSY Mechanical. Moreover, the comparison of natural frequency between the wind turbine and the gravity substructure is made to investigate the resonance. It is found that the suggested gravity substructure can be an effective substructure for 5MW offshore wind turbines.
Using the Irregular Waves based on Spectrum, the structural analysis of the hybrid substructure for offshore wind turbines is carried out through ANSY ASAS in time domain. The comparison of numerical results between P-M spectrum and JONSWAP spectrum is made to investigate the ultimate structural safety. It is found that the suggested hybrid substructure can be an effective substructure for offshore wind turbines.
In this study, analyzed of the correlation UPVand the compressive strength of structural timber. As a result, increased of UPV in accordance with the compressive strength increases. Though more experiments, judgment to be possible to estimate the compressive strength of the structural timber with UPV
This study was intended to estimate the effect of adding CNTs into cement paste on the rheological properties. it was found that higher content of CNTs increase yield stress but there was no noticeable correlation between CNTs dosage and plastic viscosity.
In this study, an analytical study on cooling period of vertical pipe cooling method was performed to determine the discontinuance time of pipe cooling.
To evaluate the prestressing loss of tendon caused by deflection angle, test is conducted with the variables of a deflection angle and a diameter of deviator head. Results show that the prestressing loss increases when the delfection angle increases but the diameter of deviator head gives no significant influence on the prestressing loss.
고속철 PSC 교량 마찰받침의 내구성 평가를 위하여 해당국내 기준의 미비로 DIN EN 1337-2 과 CUAP 기준을 적용하여 마찰판의 5000 m 이동거리에 대한 마찰 시험을 수행하였다. 적용온도와 이동속도에 따라 마찰계수를 계측하고 기준에서 요구된 상한 한계와 비교하여 고속 주행으로 발생하는 증가된 이동거리에 대한 적합한 내구성 평가기준과 실험방법을 개발하고자한다.
This study conducted the minimum weight optimum design using the differential evolution and genetic algorithm of simple structure. And then, the optimization program was verified with the numerical analysis examples of fixed beams. As a result, the graphs of these two optimization programs increased similarly.
This study analyze the buckling characteristics of trapezoidal and sinusoidal corrugation shapes with same weight. To do this, analyze the shear buckling characteristics through linear buckling analysis and on its theory.
As the weight is increased by the quantity and size of the members in large scale structures, precast column-beam joints should be designed in consideration of the assembly process. This paper was presented a way to reflect the construction difficulty such as interference of rebar at the end of beam when you design rebar joints and calculation of the length of the embedded steel.
This study aims to apply multistage homotopy perturbation method (MHPM) to SDOF space truss to obtain a semi-analytical solution. For the purpose, a nonlinear governing equation is derived in consideration of geometrical nonlinearity, and homotopy equation is formulated. The result of carrying out dynamic analysis on a simple model is compared to a numerical method of 4th order Runge-Kutta method (RK4), and the dynamic response by MHPM concurs with the numerical result.
Semi-rigid pavement is one of excellent paving methods adopting merits of asphalt-concrete and concrete paving. However, conventional paving methods were mainly used on the new constructed roads. Therefore, in this research we have examined the possibility of using the semi-rigid pavement on occupied roads. Also, confirmed the early-open possibility of pavement by applying the rapid hardening binding material to semi-rigid pavement.
This study investigates engineering characteristic of recycled aggregate concrete which incorporated various amount of recycled aggregate(0%, 30%, 50%, 100%). For the purpose of the investigation of engineering characteristic, compressive stress and air content, slump were evaluated. Evaluated results of compressive stress was shown that compressive stress and slump decreased depending on amount of recycled aggregate increased. On th other hand, air contents increased depending on amounts of recycled aggregate decreased.
The purpose of this paper is to establish specifications, to provide design database for the construction of the sea pools(30m x60m x 1.2m). When water overflows by high waves, 3D-analysis by SAP2000 software is required for designing of sea pools in order to settle the problems that the degradation of the concrete durability.
This result of analysis show that the strngth of concrete over 60MPa and the distance of 4m plie is more advantageous, then that of 2m.
Fishway analysis is required in order to protect depleting fish in the rivers. Recently, ecosystem restoration is absolutely necessary for fishes in the shallow rivers when water overflows by typhoon, 3D-analysis by SAP2000 software is required for designing of natural type of fish passage in order to settle problems regarding the degradation of the concrete durability.
This results of analysis show that natural tpe of fishway could be constructed in rivers of Korea.
3D-analysis by SAP2000 software is required for designing of sea pools in order to settle the problems regarding the degradation of the concrete durability. Sea pools are faced with sea water including salts so it will be used high strength concrete, reinforced high strength and urethane for its construction.
The purpose of this paper is to establish specifications and data base for the construction of the sea pools.
This results of analysis show that 50MPa strength of concrete is the most suitable and 4m wave is more advantageous than that of 2m.
In this study, the 3D-analysis of multi-functional fishway with underground passage and is carried out by SAP2000 soft ware.
In case of width 2m, 1m of vertical cross-section structure, the width 400mm× length 400mm and the width 1,000mm× length 400mm of square type were experimental parameters.
The multi-functional fishway with underground passage and sediment block system is propased in Jeju Island.
The demand of underground structure such as box culvert for electric power transmission is increasing more and more, and the service life extension of these structures is very important. Then, the service life due to carbonation at the cover depth was calculated by in situ information and the Monte Carlo simulation in a probabilistic way. Additionally, the accelerated carbonation test for the cracked beam specimen was executed and the crack effect owing to the carbonation process on the service life of box culvert was numerically investigated via Monte Carlo simulation based on the experimental results.
In this study, using the general-purpose structural analysis program, prediction of thermal crack of ultra-high-strength concrete(UHSC) columns were investigated. Parameters were column shape and column size of UHSC columns that have higher temperature rise than normal strength concrete. Thermal crack behaviors according to UHSC column shape were investigated.