환경친화적 굴착을 위한 SH복합파일의 실험 및 수치해석

심도식 ( Do-sik Shim ),조광준 ( Kwang-jun Cho ),박병수 ( Byung-soo Park ) 한국환경기술학회 2015 한국환경기술학회지 Vol.16 No.5

S/H 복합파일의 하중재하에 따른 변위 및 부재 응력 거동을 알아보고자 단면2차 모멘트 및 부재 강성을 고려한 강판두께와 철제 빔의 설치간격을 변화시킨 실내 축소모형실험을 실시하여 그의 거동을 수치해석과 비교분석하였다. S/H 복합 파일의 실내시험 및 수치해석 결과, S/H복합파일의 강성이 증가할수록 연직변위와 벽체의 수평변위가 감소하는 경향을 나타내었고, 평균 응력분담비는 약 2.4~5.0으로 H-pile이 더 큰 응력을 부담하였으며, 5.5 mm 강판벽체에서 약 4.0, 9.0 mm 강판벽체는 약 2.4로 Sheet pile을 모사한 강판벽체의 종류에 따라 일정한 값으로 수렴하여 강판벽체의 두께가 증가할수록 H-pile 보다 Sheet Pile의 응력 부담이 증가하는 경향을 나타내었다. Changing thickness of model steel plate as a sheet pile and the space of model beam as a H-pile with considerations of stiffnes in prototype, the reduced model experiment in laboratory was carried out to investigate behavior of displacement and stress of members induced by application of surcharge loading on the surface of ground and their results were compared with those of numerical analysis. As results of experiment and numerical analyses, increasing stiffness of reinforced sheet pile was found to have a tendency of reducing vertical displacement and lateral displacement of wall. Average stress concentration ratio was around 2.4~5.0, indicating larger stress was concentrated to H-pile. They were around 4.0 and 2.4 with 5.5 mm and 9.0 mm thickness of steel plate irrespectively so that stress concnetration value tended to converge to a certain value depending on thickness of steel plate for sheet pile in field and larger stresses were concentrated to sheet pile rather than H pile with increase of steel plate thickness.

토목섬유 구조의 거동에 대한 수리모형실험 및 수치해석

심도식(Do Sik Shim)(沈度植),이종호(Jong Ho Lee)(李鍾昊) 위기관리 이론과 실천 2013 Crisisonomy Vol.9 No.11

본 연구는 토목섬유 구조체의 해안선 적용성을 알아보기 위한 수리모형실험 및 수치해석적 연구이다. 수리모형실험은 토목섬유 구조체를 설치한 경우와 일반 토목섬유 구조체를 설치하지 않은 경우, 투수성을 개량한 토목섬유 구조체를 설치한 경우 3가지에 대하여 실시하였다. 실험결과 개량된 토목섬유 구조체를 설치한 경우 해안침식 방지효과가 발현되는 것으로 확인되었다. 한편, 토목섬유 구조체의 모래충진시 거동을 알아보기 위한 수치해석 결과 모래충진시 전단응력은 구조체 하부 측면방향으로 집중되었으며 상재하중의 영향으로 구조체 하부에 응력이 증가되는 것으로 분석되었다. 또한 뒷채움지 구조체 배면하부에서 전단응력이 증가하였고 뒷채움 하중의 영향으로 측면만곡부에서 변위증가가 최대로 발생되었다. The objective of this study is to investigate coastal applicability of geotextile through numerical analysis and hydraulic model exeperiment. Hydraulic model exeperiments were conducted in three cases: gexotile installed, normal geotextile installed, and modified geotextile permeability. Test result shows that installation of geotextile has prevention effect for costal erosion. Furthermore, in numerical analysis results to investigate behavior of geotextile in case of sand filing, shear stresses concentrate and increse the lateral direction under the geotextile as effect of overburden load. Also, shear stresses increase under the backface of backfill structure and displacement was occurred the maximum value at the side flexure as influence of backfil load.

Study on incremental roll forming for manufacture of 3D structural pipes

Do-Sik, SHIM(심도식) 한국정밀공학회 2015 한국정밀공학회 학술발표대회 논문집 Vol.2015 No.12월

전기 자동차용 경량화 서스펜션 모듈 개발

신헌섭(Yoon-Sik Jung),정윤식(Heon-Seop Shin),심도식(Do-Sik Shim),임성수(Sungsoo Rhim) 대한기계학회 2012 대한기계학회 춘추학술대회 Vol.2012 No.11

In order to improve the energy efficiency and the ride quality of the electric vehicle it is highly desirable to develope a light-weight suspension system with high travle ratio (which is the ratio of the fully extended length to the fully compressed length of the suspension). Air suspension systems with rubber tube are often considered as the optimal answer for such requirements. In this paper, a new light-weight air suspension system with high travel ratio is developed for the use in the electric vehicle. Also a FE-based multi-flexible-body dynamics (MFBD) model of the suspension system is developed as a tool for the design improvement of actual suspension system. The MFBD model includes the FE modeling of the rubber tube module as well as other essential parts of the air suspension system. The system parameters for the model were obtained from various experiments. The validity of the developed MFBD model has been shown by the comparison between the experimental results and the simulation results.

첨가질량이 존재하는 변단면 4변고정 적층복합판의 진동해석

박제선,김경진,원치문,심도식,Park, Je-seon,Kim, Kyeong-jin,Won, Chi-moon,Shim, Do-sik 강원대학교 산업기술연구소 1995 産業技術硏究 Vol.15 No.-

A method of calculating the natural frequency corresponding to the first mode of vibration of beams and tower structures, with irregular cross-sections and with arbitrary boundary conditions was developed and reported by D. H. Kim in 1974. This method has been developed for two-dimensional problems including the laminated composite plates and was proved to be very effective for the plates with arbitrary boundary conditions and irregular sections. In this paper, the result of application of this method to the clamped composite plates with non-uniform cross-section and with attached point mass/masses is presented.

굴착고 변화에 따른 S/H복합파일의 거동 분석

조광준 ( Kwang-jun Cho ),심도식 ( Do-sik Shim ),박병수 ( Byung-soo Park ) 한국환경기술학회 2015 한국환경기술학회지 Vol.16 No.1

본 연구는 Sheet Pile을 H-Pile로 보강한 S/H복합파일의 굴착고 변화에 따른 거동을 알아보기 위한 수치해석적 연구로써, Sheet Pile을 0.5 m 근입시키고 H-Pile은 0.8 m 간격으로 설치한 조건에서 배면의 굴착고를 2, 3, 4, 6 m로 각각 변화하면서 수치해석을 수행하였다. 수치해석 결과, 굴착고가 증가함에 따라 Sheet Pile과 H-Pile의 모멘트는 증가하며 최대모멘트 증가 비율이 Sheet Pile보다 H-Pile이 높게 나타나 굴착고 증가에 따라 부재내 응력전달이 H-Pile에 크게 작용함을 알 수 있었다. 또한, 굴착고가 증가함에 따라 S/H 복합파일의 수평변위 및 배면지반 변위, 각변위는 비선형적으로 증가하는 경향을 나타내었다. This paper is results of numerical study for behavior of sheet pile retaining wall reinforced with H-pile according to excavation conditions. Numerical analysis was performed to the embedded depth 0.5m of sheet pile and installed space 0.8m of H-pile, changing excavation height 2, 3, 4 and 6 m. As results of numerical analyses, increased excavation heights showed increasing moment of H-pile and Sheet pile and indicating larger stress was concentrated to H-pile. In addition, increasing excavation heights were found to have a tendency of increasing horizontal displacement and backfill displacement, angular displacement of S/H complex pile.

사각 파이프 정밀 성형을 위한 FE 시뮬레이션 기반 성형 공정 설계

손종윤(Jongyoun Son),심도식(Do-sik Shim),양희정(Heejung Yang),이은미(Eunmi Lee) 한국정밀공학회 2014 한국정밀공학회 학술발표대회 논문집 Vol.2014 No.5월

직접에너지적층 공정으로 제조된 고망간강 소재의 초음파 나노표면개질에 따른 특성 변화에 관한 연구

박한별(Han-Byeol Park),심도식(Do-Sik Shim) 한국기계가공학회 2023 한국기계가공학회지 Vol.22 No.3

This study aims to investigate the influence of ultrasonic nanocrystal surface modification (UNSM) on the hardness and roughness of high-manganese steel (HMS) produced through directed energy deposition (DED). HMS is known for its exceptional work-hardening and impact toughness, as well as its superior wear resistance. Three types of deposited HMS (13Mn, 18.5Mn, and 24Mn) were treated with UNSM, which was applied using a CNC machining process. The study sought to analyze the changes in the surface properties of the deposited HMSs according to two primary UNSM parameters: load and inter-pass interval. The results indicated that the surface hardness of the deposited HMSs improved as the inter-pass interval decreased and the static load increased. Notably, all deposited HMSs exhibited a severe plastic deformation (SPD) layer of approximately 250 ㎛ near the top surface after UNSM treatment. Conversely, the surface roughness improvement slightly decreased as the inter-pass interval decreased and the load increased, irrespective of the manganese content.

강원도 순환골재 재활용 실태 및 활성화 방안

전상현 ( Sang-hyun Jun ),심도식 ( Do-sik Shim ),박병수 ( Byung-soo Park ) 한국환경기술학회 2012 한국환경기술학회지 Vol.13 No.3

본 연구는 강원도 순환골재 재활용 활성화를 위해 국내외 관련문헌과 정책을 고찰하고, 강원도 중간처리업체의 인터뷰를 통하여 강원도 현황 및 애로사항을 정리하고 이를 종합하여 재활용 활성화 방안을 제안하였다. 연구결과, 건설폐기물 재활용 활성화를 위한 방안으로 먼저, 순환골재 활용이 용이한 의무대상건설공사 종류 및 규모, 민간공사로의 확대, 근거리 순환골재 생산업체 우선적용 등 다양한 수요처의 확대가 요구된다. 또한, 폐기물처리의 분리발주 확대 및 법적근거 마련, 품질인증 제도개선, 인센티브 제도 활성화, 통계조사 방법의 개선과 함께 품질의 개선과 대국민 인식전환 교육도 병행해야 할 것이다. In this study, to activate the recycling of recycled aggregate in Gangwon Province, related literature and policies were reviewed. In addition, via an interview with the officials of the medium-sized processing companies in Gangwon Province, the conditions and problems of the province were identified. The result of the interview were then consolidated, and a plan for the recycling of the province`s costruction wastes was suggested. As a result of this study, a plan to avtivate the recycling of Gangwon Province`s recycled aggregate was suggested. First, the demand for aggregates to a variety of markets must be met by extending the kind and scale of construction for mandatory uses and by applying them to civil construction projects, and the designation of the manufacturer of short-distance circulation aggregates must be prioritized. In addition, the separate ordering of wate disposal and the preparation of lawful grounds for such must be pursued, along with the improvement of the system for quality certification, the activation of an incentive system, the employment of a statistical research method, and the education of the people to make them recognize the importance and benefits of recycling.

최적의 정착길이 산정을 위한 인발시험에 대한 수치해석

박병수(朴炳洙)(Byung Soo Park),심도식(沈度植)(Do Sik Shim) 위기관리 이론과 실천 2012 Crisisonomy Vol.8 No.5

본 연구에서는 마이크로 파일로 지반보강을 하기 위하여 현장인발시험의 하중-변위 결과 자료를 이용하여 마이크로 파일의 최적의 정착길이 산정을 위한 수치해석을 실시하였다. 퇴적층 하부 풍화암층에 장착한 마이크로파일의 타설조건에 대하여 허용인발지지력을 산정하기 위하여 기존의 이론식과 경험식을 사용하여 분석한 결과, 10배 이상의 상이한 결과를 나타냄을 확인하여 기존식 적용시 유의하여야 할 것으로 판단된다. 지반조건 및 마이크로파일 물성에 적합한 대표값을 적용하여 수치해석을 수행한 결과, 하중-변위 특성에 대한 현장 인발 실험결과와 유사한 분석결과를 얻었다. 한편, 정착길이 변화에 의한 매개변수적 수치해석을 실시하여 주어진 설계하중에대하여 최적의 정착장 길이를 산정하였다. In this study, field pullout test has been conducted to reinforce the ground with micropiles. Numerical analysis was performed to estimate the optimum length of anchorage of micropiles using the load-displacement results. Various existing theoretical and empirical equations were used to estimate the allowable capacity of micropile anchoraged at the weathered rocks underneath sedimented deposits. Different values of pullout capacity in order of 10 times were found to obtain so that cares should be paid to use to estimate the capacity appropriately. As results of numerical analyses by applying the typical values of ground condition and properties of micropiles, similar results of load and displacement relationship of micropile to field testresult were obtained. On the other hands, parametric numerical analysis with changing the anchorage length of micropile was also performed to find the optimum anchorage length for the given design load.