본 연구에서는 불특정 분포하중에 대한 다경간 연속 보 구조물의 변형률 분포를 추정하는 기법을 제시하였다. 본 추정 기법은 해석적 방법이 아닌 계측한 변형률 데이터로부터 최소제곱법을 이용한 커브 피팅을 통해 변형률 분포를 추정하였다. 제시한 다경간 보 연속 구조물의 변형률 추정 기법은 멀티플렉싱이 가능한 FBG센서를 이용하여 다경간 연속 강재 보 정적 가력 실험을 통해 검증하였다. 실험을 통해서 분포 하중과 집중하중에 의한 변형률 분포의 추정 정확성 및 변형률 추정에 사용되는 계측점 수에 따른 추정 오차에 대한 검토를 수행하였다. 5.89 (하중 step1), 6.26% (하중 step2) 오차로 최대 변형률 지점에서의 변형률을 추정할 수 있었다. 추정을 위한 변형률 계측 센서 수를 감소시킨 경우 오차가 증가 (0.26~0.37%)하는 것 또한, 확인할 수 있었다. 회귀분석적 기법을 통해 다경간 보의 변형률 분포를추정함으로써 특정 형상의 분포 하중에 대해서만 적용이 가능한 해석적 변형률 추정 기법의 한계를 넘어 불특정 분포 하중에 대한 변형률분포 추정이 가능해졌고 추정 변형률 분포를 통해 최대변형률 발생 위치까지 확인할 수 있게 되었다.

This study was intended to estimate the axial deformation of joint between pavement modules in the rapid-constructible modular pavement system, and to investigate the applicability of two-phase composites for a joint material, which was composed of cement paste, epoxy, or polyurethane as a matrix and sand as particles.

This experimental study investigates the influence on the tensile behavior of strain-hardening cement composite (SHCC) with HR and SWP Shrinkage Reducing Admixture (SRA). SRA can also improve the tensile strength and multiple cracks of SHCC material used in this study.

This experimental study investigates the influence on the flexural behavior of strain-hardening cement composite (SHCC) with HR and SWP Shrinkage Reducing Admixture (SRA). SRA can also improve flexural strengths and flexural toughness.

We investigated Arctic plants to determine if they have a specific mechanism enabling them to adapt to extreme environments because they are subject to such conditions throughout their life cycles. Among the cell defense systems of the Arctic mouse-ear chickweed Cerastium arcticum, we identified a stress-responsive dehydrin gene CaDHN that belongs to the SK5 subclass and contains conserved regions with 1 S-segment at the N-terminus and 5 K-segments from the N-terminus to the C-terminus. To investigate the molecular properties of CaDHN, yeast were transformed with CaDHN. CaDHN-expressing transgenic yeast (TG) cells recovered more rapidly from challenge with exogenous stimuli, including oxidants (hydrogen peroxide, menadione, and tert-butyl hydroperoxide), high salinity, freezing and thawing, and metal (Zn2+), than wild-type (WT) cells. TG cells were sensitive to copper, cobalt, and sodium dodecyl sulfate. In addition, the cell survival of TG cells was higher than that of WT cells when cells at the mid-log and stationary stages were exposed to increased ethanol concentrations. There was a significant difference in cultures that have an ethanol content >16%. During glucose-based batch fermentation at generally used (30℃) and low (18℃) temperatures, TG cells produced a higher alcohol concentration through improved cell survival. Specifically, the final alcohol concentrations were 13.3% and 13.2% in TG cells during fermentation at 30℃ and 18℃, respectively, whereas they were 10.2% and 9.4%, respectively, in WT cells under the same fermentation conditions. An in vitro assay revealed that purified CaDHN acted as a reactive oxygen species (ROS)-scavenger by neutralizing H2O2 and a chaperone by preventing high temperature-mediated catalase inactivation. Taken together, our results show that CaDHN expression in transgenic yeast confers tolerance to various abiotic stresses by improving redox homeostasis and enhances fermentation capacity, especially at low temperatures (18℃).

The current seismic design code prescribes structural wall should be designed as special shear wall when building height is more than 60m and seismic design category D. The design code for the irregular wall is not provided. Therefore, the special wall with flange is designed as linear section wall. The ultimate strain of concrete in nonrectangular section would be different form that in rectangular section, then the equation of discrimination for special wall would changed. In the study, nonlinear analysis for linear and irregular wall are performed, and concrete ultimate strain is compared.

Diagonally reinforced concrete coupling beam has complicated reinforcement details. To solve this problem, it is necessary to develop the alternative reinforcement details. The objective of this study is to investigate strain characteristics of coupled shear wall according to the replacement ratio of headed-bar.

This paper describes the flexural performance of concrete and strain-hardening cement based composite (SHCC) beams reinforced with normal and high-strength steel bar to evaluate the effect of reinforcing bar strength and cement composite type. The present investigation shows the potential of high-strength structure materials used of high-strength reinforcing bars with SHCC. And superior mitigation of crack-damage is observed reinforced SHCC beams than reinforced concrete beams

Hybrid coupled shear wall with steel coupling beam has often been used to resisting system of earthquake load and transverse load. This study addresses the strain characteristics of coupling beam in hybrid wall system.

This experimental study examines the test results on the flexural behavior of strain-hardening cement composite (SHCC) with two types of Shrinkage Reducing Admixture (SRA). An influence of SRA on the flexural behaviors of SHCC mixes was observed.

To evaluate the stress-strain relationship of HVFA(High Volume Fly Ash) concrete, experiments were performed according to the ratio of fly ash usage and concrete compressive strength. Test results were shown that elasticity modulus of HVFAC was influenced by compressive strength, elasticity modulus and fly ash usage ratio. And the existing equation of stress-strain relationship had a large difference. So, new equation of stress-strain relationship for HVFAC was proposed, and the proposed results had a good correlation with test results

Strain gauges is the most common device for measuring strain. Since the electric resistance of strain gauge changes only a little, strain gauges are almost always used in a bridge configuration with a excitation source. In this study, a strain measuring method, which calculate strain by reading a resistance of strain gauge, are investigated and verified.

보 구조물의 안전성을 평가하기 위해서, 해당 부재의 구조적 상태를 보여주는 보여줄 수 있는 변형률을 기반으로 한 모니터링 시스템이 이용되고 있다. 하지만 최대 변형률과 같은 부재의 상태를 대표할 수 있는 변형률이 발생하는 정확한 위치에 센서를 설치하지 않은 한, 계측된 변형률을 토대로 합리적인 평가를 할 수 있게 하는 추가적인 프로세스가 필요하다. 이에 따라 본 연구는 변형률계에 의해 계측된 이산데이터를 이용하여 강재 보 구조물의 변형률 분포를 추정하는 기법을 제안한다. 본 기법에서는 보 구조물에 작용하는 하중을 미지의 하중으로 가정하였기 때문에, 실제 적용성을 향상 시켰다. 최종적인 변형률 분포는 회귀 분석을 통해서 함수 형태로 주어진다. 본 기법을 이용한 추정 성능을 검증하기 위해서 분포하중, 집중하중, 모멘트가 동시에 작용하는 강재 보 구조물의 휨 실험을 수행하였다. 실험을 통해 추정 변형률의 값을 직접 계측한 값과 비교해 본 결과, 임의의 위치에서도 절대 오차 2.32με 이내로 변형률을 추정할 수 있었으며, 전체 변형률 분포는 3.32% 이내의 상대오차로 얻을 수 있었다. 따라서 강재 보 모니터링 시스템에 효과적으로 적용할 수 있을 것으로 기대된다.

The coupling beams provide transfer of vertical forces between adjacent shear walls in coupled shear wall system, which creates a frame-like coupling action that resists lots of the total overturning moment induced by the wind load or seismic load. The purpose of this study is to investigate the strain characteristics performance of coupling beams with headed bar.

This study includes an analytical investigation of a composite beam consist of concrete, structural tees, and the reinforcement steel. The plastic hinge length theories are applied to this composite beam to calculate maximum deflection exactly. This composite beam can reduce the floor height compared with the reinforced concrete structure with same internal force. To calculate maximum deflection, we used plastic hinge length suggested by Corley, Sawyer and Mattock. Later, the experimental investigation should be performed to find out the plastic hinge length exactly.

A strain compatibility method is based on the strain compatibility approach proposed by AISC (American Institute of Steel Construction, Inc.). The strain compatibility method assumes a linear strain of all the members. After that, set up the equilibrium equations of the state of stress in each component for calculating the location of the neutral axis of the cross-section in the presence. In this study, the reinforced concrete simple beam is analyzed by strain compatibility method for calculating the neutral axis and the bending moment. And then, a variation of neutral axis of the reinforced concrete simple beam is measured.

This study is performed to analytic evaluate of two side constrained precast infill wall with SHCC. As a result, SHCC-E specimen shows more ductile behavior than SHCC-V specimen. Analytical results are compared with experimental results.

The objective of this study is to investigate the behavior and strain characteristics of steel coupling beam-wall connection. Test variable of this study is embedment length of steel coupling beam in the embedment region. The results showed that Specimens PSH2C-ST and PSH2C-ST experienced bearing failure, based on the observation of strain of concrete in the embedment region.

Strain Hardening Cement-based Composites(SHCCs) are attractive materials for energy dissipation and crack damage mitigation. This study investigated the flexural performance of SHCC beams layered Strain-Hardening Cement-based Composite(SHCC). The flexural behavior of RC beams carried out four-point loading test. Test results indicated that PE30_20 compared with Con30 initial cracking load, the stiffness, the yielding strength was higher.