In this study, multiple regression analysis was conducted using traffic volume, temperature and strain, which are maintenance data of suspension bridge(Diamond Bridge in Busan). As a result of analysis, the influence of independent variables on the dependent variable, strain, was found to be .304 for light and compact car traffic, .476 for large and special car traffic and .167 for the average temperature of reinforced truss

A new index for the buckling strength of non-structured plates is proposed. The traditional method of evaluating buckling strength involves inconsistancies of stress distribution while new method of checking the energy variance always provides consistent and even results in any shape of member or load and boundary conditions.

All the structures include initial imperfections that can affect the structural behavior and stability, particularly during construction. Therefore, for a concrete beam with an initial lateral deformation, creep analysis was performed to evaluate the influence of the initial imperfection on the creep deformation of the beam in the both vertical and lateral directions.

The objective of the study is to compare theoretical displacement and strain values with those obtained from experiment. The elastic load method was used to obtain the theoretical values. For comparison purpose, H-beams were tested using a three point bending test method. The load-displacement and load-strain curves from the experiment were compared to those from the theory. According to the comparison, displacement was in good agreement with less than 10% difference. Strain values showed difference ranging from approximately 11 to 30%.

본 논문에서는 물리기반 동적 변형을 실시간에 안정적으로 시뮬레이션하는 새로운 ARAP (as-rigid-as-possible) 방법을 제안한다. 1, 2, 3차원 물체의 변형을 안정적이며, 빠르고, 일관성 있게 다루기 위하여 방향성 입자로 이루어진 변형 그래프를 도입하고 그에 따른 ARAP 변형 에너지를 공식화한다. 방향성 입자의 안정적인 시간 적분을 위해서는 변분 공식화에 기반을 둔 내재적 시간 적분 기법을 개발한다. 또한 국지적/전역적 최적화를 교대로 반복 적용하여 방향성 입자의 최적 위치 및 회전을 구한다. 제안된 방법은 구현이 쉽고 복잡한 변형을 실시간에 시뮬 레이션할 수 있을 정도로 빠르다.

In this study, multiple regression analysis was conducted using traffic volume, temperature and strain, which are maintenance data of suspension bridge(Diamond Bridge in Busan). As a result of analysis, the influence of independent variables on the dependent variable, strain, was found to be .304 for light and compact car traffic, .476 for large and special car traffic and .167 for the average temperature of reinforced truss.

본 연구는 철골모멘트골조를 대상으로 변형률 기반 횡응답 예측 기법 제시한다. 기둥의 변형률 데이터를 이용하여 건물레벨의 횡 응답을 예측한다. 변형률 데이터는 한 개의 기둥 당 총 4개의 변형률 센서가 설치된다고 가정하여 기둥의 양 단부의 변형률 응답 값을 이용한다. 양단부의 변형률 값을 통해 단부의 휨모멘트를 계산하고 이를 처짐각법에 적용하면 건물레벨의 횡응답을 예측할 수 있다. 또한 한 개층에 설치 된 가속도계의 응답을 이용하여 지점에 위치한 회전스프링의 강성값을 예측하였다. 제시한 기법은 5층 1경간 철골모멘트골조 예제에 적용하 여 그것의 신뢰성를 검증하였다. 횡변위 및 횡가속도에 대한 예측 응답이 비교값과 일치하는 결과를 얻었으며, 손상 여부 및 위치를 파악하는 데 효과적임을 확인하였다. 반면 고유주기와 같은 동특성은 구조물의 손상을 파악하는데 한계가 있음을 확인하였다.

초고강도 콘크리트를 이용한 부재의 내화 성능을 검토하기 위해서는 실제부재 단위의 시험에 의한 평가가 요구되고 있다. 그러나 실제부재 실험을 하기 위해서는 재하 능력이 큰 시험 장비가 필요하기 때문에, 재료 모델을 이용한 해석적 연구를 통해 내화 성능을 평가하고 있다. 본 연구에서는 80, 130 및 180 MPa의 초고강도 콘크리트를 대상으로 고온 가열시의 변형 특성을 실험적으로 평가하고 초고강도 콘크리 트에 대한 기존 변형 모델의 적용을 검토했다. 그 후, 최소 제곱법에 의해 실험 값과 기존의 변형 모델을 적용한 계산 값의 누적 오차가 가장 작 은 상수 값을 도출하고 초고강도 콘크리트에 적용 할 수 있는 변형 모델을 제시했다.

Background : Constipation is can refer to bowel movements that are rare or hard for pass. Constipation is common symptom in current people and the treatment of constipation focused on the use of medicines or physical intervention. The aim of this study are investigates the effects of modified-extracts of Salicornia herbacea (S. herbacea) L. on constipation model. Methods and Results : To investigate the effect of these extracts on constipation model with Sprague-Dawley rats by loperamide administration, we orally administered various dosage of modified-extracts of S. herbacea. L. Then, we checked constipation-related parameters such as fecal number, colon weight, colonic transmit length, colon length as compared to the controls and ameliorated in a dose dependent manner. The results indicated that modified-extracts of S. herbacea. L. was ameliorated constipation in SD rat model. Conclusion : Based on the results, modified-extracts of S. herbacea L. and its many ingredients were considered to have effects on constipation.

Conventional approach for restraining additional lateral movement of bridge abutment is to decrease applied load by replacing rear ground with EPS block, ALC(autoclaved lightweight concrete), to increase soil resistance by applying tie-rod, geo-grid, permanent anchor, counterweight fill, and to increase lateral bearing capacity of soil by installing grouting, restraint pile. With properly restrained lateral movement of bridge abutment by applying those methods, the expansion joint and bridge bearing can be repaired after securing expansion joint gaps by cutting off concrete slabs and steel box girder. In this paper, the proposed approach for securing expansion joint gaps by restoring displaced bridge abutment to its original position with the use of hydraulic jacking device is discussed. By using hydraulic jacking device, cutting off concrete slabs and steel box girder is unnecessary.

The purpose of this study was to evaluate the dynamic mechanical properties of fiber reinforced cement composite according to the strain rate. Experiment result, the compressive strength was improved by increase the strain rate. But strain at the peak stress and elastic modulus was not affected by the strain rate.

In this study, the strain based lateral deformation estimation method for steel moment frames is presented. This method estimates the distribution of flexural moments by using strain data assumed which measured in the columns. If we know the distribution of flexural moments in the columns, we can estimate the lateral deformation of columns by using the slope-deflection method. The steel moment frame with the beam-hinge mechanism is used as an example structure. Zero-length rotational springs are considered to model joints.

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.

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.

A new array was suggested for effective leakage detection of concrete water facility. This array was modified to serve the purpose. Plus and minus currents have been installed respectively on the upstream and downstream water in order to detect the flow of water floating through the crack of facility. Potential poles in two lines have been installed closer than current sources to the weir to measure potential difference in upstream and downstream. Interpreting the potential difference data acquired by the new array, we could predict that where is the leakage zone. The possibility that can distinguish the leakage zone has been confirmed by numerical and physical modeling and problem position expected to leak was verified in field exploration.

Shock wave caused by the high-velocity impact causing the tensile strain and stress on the rear side. When the tensile strain and stress exceeds the tensile strength of the concrete, scabbing and perforation were occurred. The strain on the rear side was reduced due to improvement of the tensile strength by fiber reinforcement.

In this study, the uniaxial tensile tests were conducted to verify the difference of ductile behavior according to steel ratio of RC member. The tests were conducted on concrete compressive strength of 30MPa and SD400-D19 rebars. The steel ratio was classified with 0.59% and 2.87%. From the evaluation results based on limit state strain, both 0.59% steel ratio and 2.87% steel ratio were confirmed to exhibit more than 5% strain presented in korean highway bridge design code. But in case of 0.59% steel ratio, the decrease of limit state strain and failure strain was remarkably confirmed.

This study measured the in-plane and out-of-plane deflections of a beam using image processing technology. The deflections and rotation obtained from the vision-based measurement were compared with those from the traditional, current measurement method using three wired potentiometers. The results of this study indicated that the proposed vision-based measurement system was successfully applied to evaluating the out-of-plane deflections of a beam including the vertical in-plane deflection.

In this paper, shear strain dependence of high hardness laminated rubber bearings were studied through tests. The shear strain dependency test is considered the changes by increase the shear strain by 50%, 100% and 150% based on 100% of total rubber thickness. As the test results shear strain increases were identified a tendency to decrease the shear stiffness.