서울지역 28개 지하구조물에 대한 정밀안전진단 결과를 활용하여 제안된 균열집중구간 및 탄산화 기반 한계상태함수를 산정하여 우선적인 보수구간을 선별하고자 하였다. 상태평가를 위해 분할된 503개 쉬트에 대한 균열밀도는 로그정규분포, 탄산화 및 피복은 정규분포의 현장조사 결과를 얻었다. 각 구간별 실시한 강도, 초음파속도, CO2농도, 철근부식도, 염화물함유량 등을 고려할 수 있도록 환경지수를 도입하여 합리적인 보수 우선순위를 제안하고자 하였다.

Displacement is one of the most fundamental responses, containing useful information regarding dynamic behavior of a structure. Traditional displacement measurement devices such as LVDT have disadvantages in their high cost and few options on installation locations. For the sake of economic reason, vision-based displacement measurement systems using low cost cameras have been developed, yet these systems still have difficulties in finding appropriate camera positions; camera should be placed perpendicular to targets. This study presents a new vision-based displacement measurement system using the planar homography method that results in accurate displacement measurement, allowing the camera to face targets with an arbitrary angles. The proposed vision-based system was experimentally validated from a laboratory test.

In this study, a noncontact NDT method is implemented to detect the damage of pipeline structures and to identify the location of the damage. To achieve this foal, an Nd:YAG pulsd laser system is used to generate guided waves and a galvanometer-based laser scanner scans a specific area to find damage location. Then, a piezoelectric sensor is installed to measure structural responses. The measured time and spatial responses are transformed to data in frequency and wavenumber domain through 3-dimensional Fourier transform. Finally, damages can be detected by extracting reflected signals due to damage using wavenumber filter which eliminated strong incident waves.

The aim of this study is to experimentally verify the feasibility of the vibration control system to be implemented on 1/10 scale down floating structure with rigid body motion and propose a control algorithm to effectively control the dynamic responses of a floating structure. For this, active mass damper system was constructed and evaluated the function of each component consisting of the mass damper system.

In this paper, the filed test procedure for evaluating the performance of track structure for additional Speed-Up test on Test-Bed Section(KP 100∼128km Osong starting point). The behavior of track system corresponding the speed up of train will be identified by the analysis of the measured data.

This paper introduce a reinforcement method for vertical extension of a building using a rahmen frame structural system. This approach has to be carried out by considering the structural safety due to the additional weights being exerted to the pre-existing building. The connections to fasten both the rahmen frames and original building were designed with the axial loads and moments acting on the rahmen frame structural system, that is extended vertically. This system reduces the structure self-weight and ensures non-additional of reinforcement.

This study is to introduce a structural analysis method that can apply a unit modular system to a remodeling extension. The structural analysis process, which can reflect the behaviors between the existing building and the modular system, is performed in a five-staged structural analysis. Therefore, the example of structural analysis of an existing building is introduced.

This study is to establish a structural analysis method that can apply a unit modular system to a remodeling extension. Structural design has to be performed after considering the behaviors between the existing structures and the modular system because the modular system is added after the transformation of existing structures has been processed. The structural analysis process, which can reflect the behaviors between the existing building and the modular system, is introduced in a five-staged structural analysis.

In this paper, the seismic performance of RC frame with deterioration of structural capacity was evaluated by using capacity spectrum method. And the efficiency of retrofit by using infilled masonry was checked from the evaluation of its seismic capacity for various layout. As a results, it was found that the masonry infill wall increased the stiffness and strength, but reduced ductility.

Currently the seismic performance evaluation for existing buildings are being made simply through the review of the analytical technique corresponding to design specifications on beam, column, shear wall, joint and so on. Also the seismic performance is evaluated to 4 steps as immediate occupancy level(IO), life safety level(LS), collapse prevention level(CP), collapse occurrence level(CO). However, in case of a structure being used for a number of years after construction, which may have partial damages and durability degradations may show significant differences between the analysis results and the actual behavior during an earthquake. Therefore, a improved seismic performance assessment is proposed based on risk assessment and seismic performance techniques since more systematic evaluation and condition assessment are required, and thus the practical and economical seismic retrofit measures for the existing facilities and for the reasonable seismic design as well are to be developed more than ever before.

The Recent earthquake damage of surrounding countries is increasing, occurrence of frequent earthquakes in the country, thus, the interest about the seismic performance of the structure is increasing. Korea, was established in 2008 earthquake measures method, KBC2009 was also amended by design standards. KBC2009 based seismic design and seismic strengthening has become mandatory, Design of the building before the current seismic design standards must be satisfied in KBC2009. Therefore, ATC-40, FEMA-273 and seismic performance evaluation of Korea Infrastructure Safety Corporation will conduct the seismic performance evaluation at the Previous design code building.

Recently, it is more concerned about securing of its seismic safety, as underground structures are significantly recognized. Especially, it is very important that underground structures such as the tunnel of urban railroad or subway ensure the seismic safety of its, because it can be caused an enormous loss of lives and a economical damage by earthquake. When the subway tunnel of cut-and-cover box type is constructed, grounds are excavated and refilled. In this study, the parametric study is performed and analyzed about factors affecting seismic analysis of cut-and-cover tunnel, such as soil type, refilled range, tunnel location, etc. Consequently, it is hoped to provide the preliminary data for a better reasonable review on seismic design and seismic performance assessment of underground structures.

Recently, the demand for the seismic retrofit to existing buildings increased due to earthquake damage. And related researches are increasing in response while the researches considering the various design parameters such as strength and stiffness ratio between the existing structures and retrofit system are insufficient. Therefore, in this study, existing structure and reinforcing frame for damper are designed having different natural periods each other by setting the parameters related to strength and stiffness ratio between two systems and are analyzed by nonlinear dynamic analysis.

In this study, experimental research was carried out to evaluate the structural performance of the reinforced concrete beam hybrid retrofitting with two materials(groove and embedding FRP rod, CFRP sheet) in existing reinforced concrete buildings. Test results showed that the maximum load carrying capacity of retrofitted specimens(NER1, NER1B, NER1L) were increased by 1.11 ~ 1.22 times respectively in comparison with the standard specimen NBS.

We had designed and constructed floating type photovoltaic energy generation system, which is improved the structual and economical efficiency, compared with the system developed in the previous research. In this paper, the basic characteristics of wind force coefficient on a PV panel installed on the floating type PV energy generation system are investigated though the two-dimensional wind tunnel tests. Test variables included the angle of PV panel, direction of wind, number of rows of PV panel and attached or not attached frame. Based on the results obtained through the wind tunnel tests, it was found that the wind force coefficient can be used as a preliminary data in the design of the structure.

If the bracket triangle are commonly used, you may issues such as withdrawal caused by mounting unstable bracket phenomena and bending wire, the eccentricity of the loading plate than steel when you change the angle of the hole during construction will occur. SM brackets adjustment of the angle of 25~40 degrees is possible adjustment of the angle of the ground anchor bracket arched surface, the change in distance between the fixing position of the line and band pieces, due to changes in the installation angle, designers from steel Unlike with the intention, it is possible if the corresponding method can be constructed. Also, For construction of temporary structure used anchor, it will be reinforced with stiffener to prevent excessive deformation of the wale. In general, the welded steel stiffener is used. Construction of welded steel stiffener is costly and time-consuming and cause the problem that wale does not reuse. In order to solve these problems, various kinds of non-weled stiffeners are being developed.

Important factor of underground structures utilizing precast and rigid wall is joints and connections of wall-to-wall and wall-to-slab for safety performance and durability of underground constructions. In this study, conducting research on the structural safety of the connection as a future laboratory experiments and connection method for the verification of the details of the construction method is expected to proceed research.