In this study, to evaluate the applicability of VDMS(Vision-based Displacement Measurement System) in the field, 30m of real specimens were measured vertical displacement using the VDMS and a displacement Transducer. The VDMS was to take a picture by attaching Target on the structure. Then, by analyzing the video in Digital Image correlation algorithm obtained a displacement of the structure. The vertical displacement of 30m real specimens using the VDMS and a displacement Transducer was very similar, and it is determined that the VDMS has a high applicability in the field.

When attaching the building exterior, builder used welded-building hardware in general. But it caused variety accidents like fires and explosions. Thus in this study, we developed the building hardware that not use welding and can follow the structures horizontal displacement when an earthquake occurs in the load building. And shaking table test was conducted.

The light rail transits, in theses days, are planed to be introduced in Korea. However, there are more and more problems regarding the noise and vibration from the trackway. In order to reduced the vibration and noise, various method have been applied. Among those methods, it is that one of the most effective ways is to apply the floating mat underneath the slab track. In this stud, a numerical modeling to calculate the effect of the floating mat is to be used as well as the performance of the floating track.

To verify the displacement estimation method which is based on the relation between displacement and strain, static and dynamic field test are performed on the real bridge structures. Static and dynamic displacements estimated by using strain signal are well agreed with measured one by LVDT. This study demonstrates that the displacement estimation method using strain signal can be effectively applied to the displacement measurement of bridge structures, which are crossing the river/road/railway or have high clearance.

To realize a robot hand interacting like a human hand, there are many tactile sensors sensing normal force, shear force, torque, shape, roughness and temperature. This sensing signal is essential to manipulate object accurately with robot hand. In particular, slip sensors make manipulation more accurate and breakless to object. Up to now several slip sensors were developed and applied to robot hand. Many of them used complicate algorithm and signal processing with vibration data. In this paper, we developed novel principle slip sensor using separation layer. These two layers are moved from each other when slip occur. Developed sensor can sense slip signal by measuring this relative displacement between two layers. Also our principle makes slip signal decoupled from normal force and shear force without other sensors. The sensor was fabricated using the NBR(acrylo-nitrile butadiene rubber) and the Ecoflex as substrate and a paper as dielectric. To verify our sensor, slip experiment and normal force decoupling test were conducted.

본 연구에서는 기존의 가속도 등을 이용하여 변위를 추정하는 방법의 문제점을 개선시키기 위해 단순지지 거더교의 실측 변형률로 부터 변위를 추정할 수 있는 간단한 방법을 제안하였다. 제안된 변위 추정 방법의 기본 개념은 변위와 변형률의 관계로부터 유도되었으며, 해 석적 방법을 부가적으로 도입하여 일반화시켰다. 실교량과 유사한 동적 거동특성을 갖는 단순지지 강판에 대한 정․동적 실내실험을 수행하였 으며, 실험을 통해 실험체 중앙점의 변위 및 변형률을 측정하였다. 실험체에 대한 실측 변형률을 이용하여 추정된 변위는 실측 변위와 잘 일치 하는 것으로 나타났다. 본 연구에서 제안한 변위 추정 방법은 변위계 설치를 위한 고정된 기준점 확보가 곤란한 실교량(단순지지 거더교)의 변 위 측정에 적합하다고 판단된다.

Because stage cable-bridge have long spans and large members, their movements and geometrical changes by temperatures tend to be bigger than those of small or medium-size bridge. Therefore, it is important for maintenance engineers to monitor and assess the effect to temperature on the cable-supported bridges. To evaluate how much the superstructure expands or contracts when subjected to changes in temperature is the first step for the maintenance. Thermal movements of a cable-stayed bridge in service are evaluated by using long-term temperatures and displacements data.

Improvement of displacement absorbing performance by utilizing the moving clips in order to prevent falling off of the exterior material according to earthquakes and wind, trying to examine the structural performance of the building exterior panel.

The four buckling resistance steel dampers were tested under cyclic lateral load to investigate the relationship of lateral load and displacement. The main variables are the existence of cover plate for preventing from buckling of out-of-plane and thickness of sim plate with 3.2 mm, 4.5 mm and 7.0 mm. The test showed that steel damper with cover plate had the wider area of its hysteresis loop than that of without.

By the earthquake and the wind against the displacement that occurs in buildings by utilizing the movement of the clip architectural exterior panels can follow the displacement and deformation by preventing the loss of architectural exterior panels to protect life and property.

Selection of a typical four companies products of domestic structural one-component sealant, high temperature, low temperature, room temperature to set up the environment for each of 80, -20, 20 ℃ and the left and right displacement of the test piece 30, 15, 0% of the maximum compression / expansion It was carried out by the repeated fatigue.

This study proposes a measurement method using angular sensors to measure deformation and displacement of bridges. The proposed measurement method consists of gyroscope sensors and data processor to transform angular to vertical displacement. This study contains experimental evaluation to verify the applicability of the proposed method. 4-points bending tests were conducted on a small-sized girder specimen. The displacements were measured with both conventional LVDT and gyroscope sensor to compare the accuracy of the proposed method. It is estimated that the method using gyroscope shows some noise in data, but the method using gyroscope has advantages to measure the vertical displacement. Therefore if the sampling rate and synchronizing problems can be approved, it can be a good alternative measuring method for the deformation of the bridges.

Impact factor for used in the load carrying capacity evaluation of bridges is varied depending on vehicle speed and bridge frequencies. So, it is hard to define its peak value since in the field test the truck speeds applied cannot cover all possible vehicle speeds and the speed per each vehicle loading test cannot remain constant consistently. Furthermore, the target bridges should be closed during field test, which leads to an inconvenient traffic flow. In this paper, a displacement-based response spectrum of bridges is considered to define the peak impact factor without conducting the standard vehicle loading test, while using a bridge operational traffic condition.

Reconstruction of the bridge is constructed to well foundation at the basement. Therefore, the existing bridge should evaluate the impact according to blasting construction. The result of displacement are presented the standard dispacement of the existing bridge.

Recently, an indirect displacement estimation method using data fusion of acceleration and strain (i.e., acceleration-strain-based method) has been developed. This paper proposes an improved displacement estimation method that can be applied to more general types of bridges by building the mapping using the finite element model of the structure. An experimental validation of the proposed method was carried out on a prestressed concrete girder bridge, and the method provides the best estimate for dynamic displacements.

Computer vision-based displacement measurement is regarded as an excellent alternative to conventional displacement measurement devices due to its convenient installation process with high accuracy. Based on the strong potential, this study proposes a computer vision approach for displacement measurement with enhanced field applicability. Main features of the proposed method are (1) robustness against adverse light conditions and (2) convenient camera installation that allows the camera to be arbitrarily placed. An adaptive image processing procedure is developed to overcome false identification of target markers that can be induced by strong lights. Location information of the identified markers are used to obtain displacement using the homography transformation, which allows the camera to be installed in any place as long as the target markers are in the line of sight. With these features, the computer vision approach is experimentally proven to be practical in field testing for measuring structural displacement.

Recently efficient maintenance technology has been rising because of the structural deterioration. Specific technology development and research related to the real-time monitoring has been conducted in various ways. All-in-one enclosure including GPS was fabricated to measure the displacement of the retaining wall structure exposed the extreme environment such as very high and low temperature. Also it measured the displacement of the structure under the phased construction.

Current design codes (AASHTO, Korean Highway Bridge Design Code) do not account for dynamic effects. Since, the dynamic impact analysis is complicate to recommend and analysis. In this study, concrete bridge column were developed with two boundary conditions in order to take account dynamic behavior of the column and in-direct impact analysis was conducted. Furthermore, a comparison study of in-direct impact analysis with direct impact analysis was conducted.

This case study is evaluation of pier safety for horizontal displacement come from a pile of rock muck under construction, restoration measure and application of repair and reinforcement.

A video-based non-contact remote displacement measurement system is proposed and developed. The system captures images of the structure and analyzes the image to determine the displacement. Multi-thread computing and adaptive region of interest method is implemented in the system to compute the displacement in real-time. Field test on a real structure has been carried out to evaluate the performance and verify the reliability of the system.