부착식 주입형 철근앵커의 부착강도에 관한 실험적 연구

서성연 한국방재학회 2013 한국방재학회논문집 Vol.13 No.2

The use of post-installed anchors with adhesive type has lately been increasing when it is necessary to repair, reinforce, or remodel structures because this constructing method has flexibility and simplicity of construction in adhering or fixing structural members. Meanwhile, strength evaluation of anchors with expansion type among postinstalled anchors systems has nearly reached setting-up stage like design code through continual experimental studies for the last ten years, but analysis or experimental studies on anchor system with adhesive type are not sufficient yet. Accordingly, we performed pull-out tests to analyze the bond strength of re-bar anchors with adhesive type embedded in non-cracking plain concrete, with variables such as anchor diameter, embedded length, and edge distance. As a result, we got the following results. 1) As a result of linear regression analysis on the bond strength of re-bar anchors with adhesive type by the anchor diameter, it showed that bond strength reduced by 0.15MPa per 1mm diameter. 2) As a result of linear regression analysis on the bond strength of re-bar anchors with adhesive type by the embedded length, bond strength reduced by 4.9% each when the embedded length reduced by 0.1 times of the standard embedded length. 3) The value of 5% fracture probability, applying the influence coefficient by the edge distance of re-bar anchors with adhesive type, resulted in 1.2. 최근 건축물의 보수·보강 및 리모델링시 구조부재를 부착시키거나 고정하는데 있어서 시공의 유연성 및 용이성으로 부착식후설치 앵커의 사용량이 증가하고 있는 실정이다. 그동안 후설치 앵커중 확장식 앵커시스템에 대한 내력평가는 지난 10년간 실험을 통한 연구가 지속되어 설계기준 제정등 어느정도 정립단계에 있으나 부착식 앵커시스템에 대한 해석 및 실험적 연구는아직 미비한 실정이다. 따라서 본 연구에서는 비균열 무근콘크리트에 매입된 부착식 주입형 철근앵커의 부착력을 평가하기 위하여 앵커직경, 묻힘길이 그리고 연단거리를 변수로 한 인발실험을 실시하였으며, 실험결과 다음과 같은 결론을 얻었다. 1) 부착식 주입형 철근앵커의 앵커직경에 따른 부착력을 선형회귀분석한 결과, 직경 1 mm당 0.15 MPa 감소하는 것으로 나타났다. 2) 부착식 주입형 철근앵커의 묻힘길이에 따른 부착력을 선형회귀분석한 결과, 표준묻힘길이의 0.1배 작아질수록 약 4.9% 낮게 나타났다. 3) 부착식 주입형 철근앵커의 연단거리에 따른 영향계수를 적용한 5% 파괴확률 값은 1.2로 평가되었다.

Naloxone의 Polyphosphazene 이식제제에 관한 연구

서성연,박주애,김길수 梨花女子大學校 藥學硏究所 1998 藥學硏究論文集 Vol.- No.7

For the effective administration of naloxone. we attempted to investigate the naloxone sustained-release implants. Using the biodegradable polymer, poly〔(diethyl glutamate)-co-(ethyl glycinate)phosphazenes〕(PGGP). the implantable devices containing naloxone hydrochloride(NLX·HCI) and naloxone base(NLX) were prepared. The release rates of NLX and NLX·HCI were compared. Influences of NLX contents on release rates were examined. For pharmacokinetic studies, NLX and NLX·HCI loaded devices were implanted subcutaneously in rabbits and then the plasma concentrations of NLX were determined by HPLC(ECD). NLX-containing devices were implanted with various doses and pharmacokinetic parameters according to dose were calculated. The relative bioavailabilities were evaluated and compared. Incorporation of NLX in the polymer leaded to a slow release. There were no differences of release rates based on drug contents. In pharmacokinetic parameters determined in 216 hours. NLX loaded devices resulted in enhanced bioavailbility with the higher AUC(p<0.01) than NLX·HCI loaded devices and MRT was significantly (p<0.05) increased. This result demonstrates that NLX is more suitable for sustained release devices than NLX·HCI. Therefore it is anticipated that the effective concentrations of naloxone could be maintained for longer periods and bioavailabilities could be improved by naloxone sustained-release implants. with varying drug base/hydrochloride.

鋼管柱의 挫屈耐力에 관한 硏究 : 정방향 각형강관주를 중심으로 On square steel pipe columns

서성연,김규석 동국대학교 산업기술연구원 1993 산업기술논문집 Vol.5 No.-

This study is a series of experimental investigation on the buckling strength of centrally and eccentrically loaded cold-formed square steel columns. In square steel column sections, residual stresses are introduced by cold-forming and welding, and at the same time, material strength is increased by the strain hardening and strain aging. These two effects will strongly influence the buckling behavior of centrally and eccentrically loaded cold-formed square columns. This paper is to research local buckling behavior, and flexural buckling behavior of cold-formed square steel columns, and attempts to improve the predictability of performance of these products as structural compression members.

고강도콘크리트충전 각형강관장주의 내력에 관한 실험적 연구

서성연,정진안,Seo, Seong Yeon,Chung, Jin An 한국강구조학회 2002 韓國鋼構造學會 論文集 Vol.10 No.4

본 논문에서는 고강도콘크리트충전 각형강관장주에 대한 실험결과와 탄소성해석결과를 비교분석했다. 실험체는 모두 고강도콘크리트 충전 각형강관장주로 18개를 제작하였으며, 편심비에 따라 중심 및 편심가력하였다. 본 연구의 주요 파라메타는 단면폭에 대한 유효좌굴 길이의 비($L_K$/D)= 4, 8, 12, 24, 30와 가력편심비(e)=0, k, 3k이다. 본 논문에서 고강도콘크리트 충전 각형강관장주의 내력에 관한 해석 및 실험을 통하여 다음과 같은 결과를 얻었다. $L_K$/D=12 이하의 고강도콘크리트충전 각형강관단주는 콘크리트 감소계수 $c{\gamma}u=0.85$를 고려한 전소성내역에 도달했으나, $L_K$/D=18 이상의 장주실험체는 콘크리트 감소계수를 고려한 전소성내력에 도달하지 않았다. 실험에 의한 고강도콘크리트충전 각형강관장주의 탄소성거동은 제안된 해석치의 종국내력$N_{ASSUMED}$과 비교적 양호한 접근을 보여주었다. 콘크리트 압축강도의 감소계수 $c{\gamma}u=0.85$를 고려하지 않은 CFT설계기준과 고강도 콘크리트를 충전한 각형강관기둥의 실험결과치는 비교적 잘 일치함을 알 수 있었다. In this paper, 18 square CFT columns filled with high-strength concrete were tested under concentric or eccentric axial loading. Two parameters of the experimental program included the buckling length-section depth ratio ($L_K$/D) and the eccentricity of the appled compressive load (e). In additon, mechanical properties such as the compressive concrete strength and compressive and tensile steel strength were measured and incorporated into the material models for the stress-strain relationships of concrete and steel. This model was used in an elasto-plastic analysis in order to predict the behavior of the slender CFT columns. Observtions of the failure mode during the tests under axial loadig were also presented. The strengths obtained from the analysis. Recommendations for Design, and Constructions of CFT structures were presented, as verified by the experimental results.

2축휨을 받는 고강도콘크리트충전 각형강관기둥의 내력에 관한 연구

서성연,케이고 츠다,아츠시 나카무라,Seo, Seong Yeon,Keigo, Tsuda,Atsushi, Nakamura 한국강구조학회 2002 韓國鋼構造學會 論文集 Vol.10 No.3

중심 및 2축편심압축에 대한 고강도콘크리트충전 각형강관기둥에 대해 실험 및 해석을 수행하며, 실험변수는 기둥의 좌굴길이대 단면폭의 비 $L_k/D$, 편심의 크기 e, 그리고 편심하중의 각 ${\theta}$이다. 실험을 통하여 2축휨을 받는 고강도콘크리트충전 각형강관기둥의 내력 및 거동을 조사한 결과, 2축편심압축력을 받는 CFT기둥의 실험에 의한 최대내력 및 거동은 해석에 의한 값과 비교적 잘 일치하였다. Maximum-strength concrete-ailed steel square tubular columns were tested under concentric and biaxial eccentric load. Buckling length-section depth ratio $L_k/D$, magnitude of eccentricity e, and angle of eccentric load ${\theta}$ were selected as experimental parameters. Strength and behavior were also examined. Test results showed that the maximum strength of columns under biaxial eccentric load could be predicted using the previously proposed strength formula of columns under uniaxial eccentric load. Likewise, the behavior and maximum strength of columns could be predicted using the analysis.

부착식 주입형 철근앵커의 부착력에 관한 실험적 연구

서성연,Seo. Seong Yeon 한국방재학회 2013 한국방재학회논문집 Vol.13 No.2

최근 건축물의 보수 보강 및 리모델링시 구조부재를 부착시키거나 고정하는데 있어서 시공의 유연성 및 용이성으로 부착식 후설치 앵커의 사용량이 증가하고 있는 실정이다. 그동안 후설치 앵커중 확장식 앵커시스템에 대한 내력평가는 지난 10년간 실험을 통한 연구가 지속되어 설계기준 제정등 어느정도 정립단계에 있으나 부착식 앵커시스템에 대한 해석 및 실험적 연구는 아직 미비한 실정이다. 따라서 본 연구에서는 비균열 무근콘크리트에 매입된 부착식 주입형 철근앵커의 부착력을 평가하기 위하여 앵커직경, 묻힘길이 그리고 연단거리를 변수로 한 인발실험을 실시하였으며, 실험결과 다음과 같은 결론을 얻었다. 1) 부착식 주입형 철근앵커의 앵커직경에 따른 부착력을 선형회귀분석한 결과, 직경 1 mm당 0.15 MPa 감소하는 것으로 나타났다. 2) 부착식 주입형 철근앵커의 묻힘길이에 따른 부착력을 선형회귀분석한 결과, 표준묻힘길이의 0.1배 작아질수록 약 4.9% 낮게 나타났다. 3) 부착식 주입형 철근앵커의 연단거리에 따른 영향계수를 적용한 5% 파괴확률 값은 1.2로 평가되었다. The use of post-installed anchors with adhesive type has lately been increasing when it is necessary to repair, reinforce, or remodel structures because this constructing method has flexibility and simplicity of construction in adhering or fixing structural members. Meanwhile, strength evaluation of anchors with expansion type among post-installed anchors systems has nearly reached setting-up stage like design code through continual experimental studies for the last ten years, but analysis or experimental studies on anchor system with adhesive type are not sufficient yet. Accordingly, we performed pull-out tests to analyze the bond strength of re-bar anchors with adhesive type embedded in non-cracking plain concrete, with variables such as anchor diameter, embedded length, and edge distance. As a result, we got the following results. 1) As a result of linear regression analysis on the bond strength of re-bar anchors with adhesive type by the anchor diameter, it showed that bond strength reduced by 0.15MPa per 1mm diameter. 2) As a result of linear regression analysis on the bond strength of re-bar anchors with adhesive type by the embedded length, bond strength reduced by 4.9% each when the embedded length reduced by 0.1 times of the standard embedded length. 3) The value of 5% fracture probability, applying the influence coefficient by the edge distance of re-bar anchors with adhesive type, resulted in 1.2.

후시공 부착식 캡슐형 및 주입형 케미컬앵커의 인발내력에 관한 실험적 연구

서성연 한국복합신소재구조학회 2022 복합신소재구조학회논문집 Vol.13 No.1

Recently, post-installed chemical anchors of the bond type are increasingly used in the repair, reinforcing, and remodeling of buildings to attach or fix structural members owing to their flexibility and availability. In addition, the use of post-installed chemical anchors of the bond type has increased significantly since 2000,sfor remodeling and construction of structural buildings. Meanwhile, the strength evaluation of expansion anchors among post-installed anchors systems has practically reached the setting up stage, similar to design code, through continuous experimentation in the last decade. However, no credible design code or construction specification for chemical anchors of bond type has been established. Accordingly, Korean designers and builders rely on foreign design codes because there is no exact domestic design code available. Therefore, this study presents the basic technical data on the chemical anchors of the bond type that are used in the remodeling and construction of buildings. Experiments were conducted to evaluate the pullout strength and fracture mode of chemical anchors implanted in concrete. The experimental variables were anchor diameter, embedded length, edge distance, and anchor interval for the chemical anchors of the bond type that are post-installed in uncracked and unreinforced concrete. According to the test results, the capacity increase ratio rose by a certain percentage based on the anchor diameter, embedded length, edge distance, and anchor interval. 최근 건축물의 보수보강 및 리모델링시 구조부재를 부착시키거나 고정하는데 있어서 시공의 유연성 및 용이성으로후설치 부착식 케미컬앵커의 사용이 증가하고 있는 실정이다. 그동안 후설치 익스팬션앵커에 대한 내력평가는 지난 10년간 실험을 통한 연구가 지속되어 설계기준식 제정등 어느정도 정립단계에 있으나, 부착식 케미컬앵커에 대한 해석 및 실험적 연구는아직 미비한 실정으로, 현재 설계자와 시공자가 신뢰할 수 있는 명확한 설계기준이 없는 상태로서 외국의 설계기준에 의존하고있는 실정이다. 따라서 본 연구에서는 부착식 캡슐형 및 주입형 케미컬앵커의 볼트직경, 매입깊이, 연단거리 그리고 앵커간격를변수로 한 인발시험을 통하여 비균열 무근 콘크리트에 매입된 케미컬앵커의 인발내력에 미치는 제요소를 분석하고, 구조적 안정성을 고려한 합리적인 부착식 케미컬앵커 설계를 위한 기초자료를 제공하는 것을 그 목적으로 한다.

부착식 앵커의 전단내력에 관한 연구

서성연 한국방재학회 2016 한국방재학회논문집 Vol.16 No.6

최근 건축물의 보수, 보강 및 리모델링시 구조부재를 부착시키거나 고정하는데 있어서 시공의 유연성 및 용이성으로 부착식 후설치 앵커의 사용량이 증가하고 있는 실정이다. 그동안 후설치 앵커중 확장식 앵커시스템에 대한 내력평가는 지난 10년간 실험을 통한 연구가 지속되어 설계기준 제정등 어느정도 정립단계에 있으나 부착식 앵커시스템에 대한 해석 및 실험적 연구는 아직 미비한 실정이다. 따라서 현재 우리나라에서는 설계자와 시공자가 신뢰할 수 있는 명확한 설계기준이 없는 상태로서 외국의 설계기준에 의존하고 있는 실정이다. 본 연구에서는 부착식 케미컬 앵커를 대상으로 연단거리 및 앵커간격 그리고 하중방향에 따른 전단실험을 통하여 무근콘크리트에 매입된 케미컬 앵커의 부착강도에 미치는 영향을 규명하고 합리적인 케미컬 앵커의 설계기준 제정을 위한 기초자료를 제공하는 것을 목적으로 한다. The use of post-installed anchors with adhesive type has lately been increasing when it is necessary to repair, reinforce, or remodel structures. This method provides flexibility and simplicity for construction of structural members that require adhering or fixing. Meanwhile, strength evaluation of anchors with expansion type among post-installed anchors systems has nearly reached setting-up stage like design code through continual experimental studies for the last ten years, but analyses or experimental studies on anchor system with adhesive type are not yet sufficient. Accordingly, the designers and builders of Korea depend on foreign design codes since there are no exact domestic design code they could credit. In this study, the objectives are investigating the effects on adhesive strength of anchors embedded into plain concrete by shear experiments of anchors with variables such as edge distance, anchor interval, and load direction and supplying basic data for enactment of domestic design code.

병원약사에 의해 수행되는 약제서비스의 현황 및 업무량 분석

서성연,김시형,김성환,김아정,김현정,배혜정,백진희,신은정,임정미,장홍원,최나이,최정윤,조윤희,조은정,조윤숙,김혜린 한국병원약사회 2020 병원약사회지 Vol.37 No.2

Background : In Korea, the reimbursement price is determined based on the resource-based relative value scale (RBRVS) system comprising physician (pharmacist) work, practice expense, and the professional liability insurance component. The purpose of this study was to define and measure pharmacists’ activities in hospital to compute appropriate reimbursement prices for pharmacists’ services. Methods : We defined the activities of hospital pharmacists as 38 duties/124 tasks/489 task elements and surveyed all pharmacists in the pharmacy department of Seoul National University Hospital. The conducting duration for each task depended on the daily (or monthly) occurrence via the self-reporting method. The proportion of duration for each task during the total working period (480 minutes/day) was calculated and compared by sector. Results : For the 110 respondents, the duration proportion of work related to dispensing was the highest at 63.3%, followed by clinical pharmacy services and medication counseling at 16.7%, drug information and administration at 7.0%, education and research at 4.5%, indirect activity at 4.0%, and work for clinical trials at 1.5%. Facilities & environmental management, quality improving activity, managing health information systems, monitoring adverse drug reactions, and participating in committee activities had a lower proportion at under 1%. Conclusion : Our results present a good reflection of the working activities for the actual hospital pharmacy, and it shows that work related to dispensing continues to consume a large portion of time among hospital pharmacy services. The definition of the detailed work performed by the hospital pharmacist and the survey of the workload from our study are meaningful in that it could be used as necessary evidence when needed to compute reimbursement prices for new pharmaceutical care services in the future.

A Study on the Shear Strength of Expansion Anchorsby Probabilistic Analysis

서성연 대한건축학회지회연합회 2023 대한건축학회연합논문집 Vol.25 No.5

This study concerns the prediction of shear capacity, as governed by concrete breakout failure, concrete pryout failure, and steel failure, and of single anchors located close to free edge and located far from a free edge and installed in untracked, unreinforced concrete. For this purpose, the methods to evaluate the shear capacity of the single anchors in concrete are summarized, and the experimental data are compared with shear strengths using the two current methods: the ACI 349-90 and concrete capacity design methods. Based on the results of the experiments, the constant 0.568 in the steel strength equation of a wedge anchor was determined from test data at 5% fractile probability. In terms of the CCD method, a normalization coefficient of 0.659 is appropriate for single near-edge anchors loaded in shear.