국내 노상토의 M_R특성 분석을 위한 실험적 연구

문홍득,신영철 진주산업대학교 1997 산업과학기술연구소보 Vol.- No.4

The deflection and deterioration of road surfaces are largely related to the deformation of underlying soils. The American Association of State Highways and Transportation Officials(AASHTO) has adopted use of resilient modulus in the pavement design to represent the deformational characteristics of pavement materials due to repeated loading. Because of the recent interest in the use of resilient modulus for pavement design, it is needed to evaluate on the effects of moisture, soil type, and stress state on resilient modulus. In this paper, resilient characteristics are investigated for subgrade soils gained from road construction sites in Korea. The experimental technique basically follows the method suggested in this study.

건설공사장의 지반진동 예측 및 진동저감공법의 효과 분석

문홍득 진주산업대학교 2001 산업과학기술연구소보 Vol.- No.8

Recently, many kinds of huge construction works are being constructed in many places in Korea. The use of big construction equipments, pile driving and rock mass blasting accompany with construction are powerful sources of ground vibrations which may effect surrounding buildings and have detrimental effects on other structures, sensitive devices, people and animals. These environmental problems such as noise and ground vibrations induced by construction have gained public interest because people desire better living life. From this point of view, it is desirable to study for assessment potential vibration problems which may arise at the time of construction works and for making an effective counter plan against the ground vibration. In this paper, the program able to simply predict the ground vibration caused by construction works, especially pile driving and rock mass blasting, was developed. And also, the methods for reducing ground vibration using EPS and crashed stone barriers were proposed and the experimental data for reducing effect of vibration of the proposed methods were presented.

열차주행으로 발생되는 인접지역의 지반진동 특성 분석

문홍득,김우중 진주산업대학교 건설기술연구소 1998 건설기술연구소보 Vol.1 No.-

In recent years, environmental problems such as noise and ground vibration induced by many kinds of construction and running trains have gained public interest because people desire and require better living life. Running trains are also one of sources of noise and vibrations which may effect adjacent house and have detrimental effects on other structures, sensitive devices and people. Especially domestic animals and fishes are heavily effected from only low levels of vibration. Consequently, the resonable methods for vibration-reducing is adopted. From this point of view, it is desirable to make preliminary analysis to correctly assess potential vibration problems which may arise at the running of train and to provide the valuable data to make an effective counter plan against such ground vibrations. This paper presents the results of measurements of ground vibration on the adjacent soil surface of railway which is running train, and supply valuable data for selection of a suitable vibration-reducing method. The levels of vibration and the attenuations with distance for ground vibrations are also considered.

말뚝항타에 의한 지반진동 영향 평가 연구

문홍득,정대석 진주산업대학교 1999 산업과학기술연구소보 Vol.- No.6

Recently, many kinds of huge construction works are being constructed in many places in Korea. Among these projects, especially at the high speed rail construction sites, many bridge foundations are being built with steel pipe pile foundations because much of this construction occurs on low-lying ground and farmlands. Pile foundations are often used for a wide range of buildings, bridges, and other structures. So, piling operations are powerful sources of construction vibrations which may effect surrounding buildings and have detrimental effects on other structures, sensitive devices, processes and people. In recent years, this problem has gained public interest so people desire and require better living environments. And consequently, the high tech equipment necessary for vibration-proofing has been developed. From this point of view, it is desirable to make preliminary analysis to correctly assess potential vibration problems which may arise at the time of pile driving and to provide the valuable data to make an effective counter plan against such ground vibrations. This paper presents the results of measurements of round vibration on the soil surface of high speed railway construction sites caused by pile driving and supply valuable data for selection of a suitable pile driving method in other sites. The levels of vibration and the attenuations with distance of ground vibrations are also considered, together with the criteria and standards for vibration assessment with respect human and animal response as well as building damage.

관거의 기초 및 뒷채움재로 활용하기 위한 석분의 공학적 특성

문홍득,김대만 한국지반환경공학회 2006 한국지반환경공학회논문집 Vol.7 No.6

In this study, basic physical tests and mechanical tests of crushed rock were performed in order to investigate the field application of crushed rock as substitute materials of sand that is commonly being used as foundation and backfill materials of sewer conduit. Particle-size distribution curve of crushed rock is similar to sand and also it is well-graded soil than common sand. Maximum dry unit weight in proctor compaction test for crushed rock is higher than the values of common sand. So we can estimate that the crushed rock has advantages in workability than sand for the backfill compaction after construction of sewer conduit. When we investigate the results of direct shear test and triaxial compression test on the crushed rock, it has a similar value of shear strength parameters to sand at the same stress state and as time goes by, it tends to increase the unconfined compression strength. But, because the strength reaches at the constant value after 6~7 days, we expect that it can absorb the lateral strain of flexible conduit well. All the above experimental results just proves that crushed rock can substitute for sand as backfill materials and foundation of sewer conduit. 본 연구에서는 하수관거의 기초나 뒷채움재로 많이 사용되고 있는 기존의 모래를 대체할 재료로써 석분의 적용가능성을 평가하기 위하여 석분재료에 대한 기본적인 물리적, 역학적인 특성실험을 실시하였다. 석분의 입도분포는 모래보다 더 좋은 상태를 나타내며, 다짐실험 결과도 모래보다 강도특성이 좋은 것으로 나타났다. 이러한 실험결과로부터 하수관거의 기초 및 뒷채움재로써 석분은 현장적용성이 우수한 것으로 평가되며, 이를 뒷받침하기 위하여 직접전단시험, 삼축압축시험을 실시하여 강도특성을 분석한 결과 모래의 경우와 유사한 경향을 나타내었다. 석분의 경우 일축압축강도 특성은 시간이 지남에 따라 점차 증가하는 경향을 보이지만 6~7일 경과 후에는 거의 일정한 값을 보이는 것을 알 수 있었다. 이와 같은 실험결과로부터 석분도 하수관거의 기초 및 뒷채움재로 충분히 활용할 수 있는 재료로 평가되었다.

열자주행으로 발생되는 인접지역의 지반진동 특성 분석

문홍득 진주산업대학교 2000 산업과학기술연구소보 Vol.- No.7

In recent years, environmental problems such as noise and ground vibrations induced by many kinds of construction and running trains have gained public interest because people desire and require better living life. Running trains are also one of sources of noise and vibrations which may effect adjacent house and have detrimental effects on other structures, sensitive devices and people. Especially domestic animals and fishes are heavily effected from only low levels of vibration. Consequently, the resonable methods for vibration-reducing is adopted. From this point of view, it is desirable to make preliminary analysis to correctly assess potential vibration problems which may arise at the running of train and to provide the valuable data to make an effective counter plan against such ground vibrations. This paper presents the results of measurements of ground vibration on the adjacent soil surface of railway which is running train, and supply valuable data for selection of a suitable vibration-reducirig method. The levels of vibration and the attenuations with distance for ground vibrations are also considered.

현장계측 자료분석을 통한 암반내 초기응력의 평가

문홍득 진주산업대학교 2000 산업과학기술연구소보 Vol.- No.7

Although a number of techniques have been proposed and developed to determine initial stress in rock mass, the determination of initial stress is not an easy task and all suffer from deficiencies and limitations. The main deficiency of established techniques such as over coring method or hydraulic fracturing method which is currently used in Korea is that they are usually expensive and time consuming. This paper presents a guide to determine the resonable initial stress for tunnel design through the analysis of field instrumentation data measured in Korea.

터널해석에 있어서 적정 하중분담율의 결정 연구

문홍득,설진성 진주산업대학교 1999 산업과학기술연구소보 Vol.- No.6

3-D structure is created at the tunnel face in all tunnelling. Accordingly, the ground around the tunnel under construction shows three dimensions deformational behavior due to the transverse and longitudinal arching effects. In order to obtain the realistic results of these the tunnel behavior from the numerical analysis, actual construction measures and their sequence must be taken into account. In particular, the excavation and installation of support and lining are important tunnel construction parameters. Despite these three dimensionalities encountered in tunnelling, a three-dimensional analysis is often not necessary. Instead, a two-dimensional model can be substituted because of the size and complexity associated with a 3-D model and calculation times to perform a 3-D analysis. The simulation of 3-D conditions by a 2-D model requires experience and the understanding of the relationship between theses two models. Load distribution ratio is used to the 2-D analysis for the consideration of the effects of the tunnel advance in three dimensions in Korea. However, constant load distribution ratios have been assigned for 2-D analysis even if the conditions for tunnel design are different. This paper presents the results of the evaluation of load distribution ratios through a three-dimensional tunnel analysis for the different ground formation and compares the cases of load distribution ratios applied actual tunnel design in Korea.

평균 및 위너 필터를 사용한 영상 복원에 관한 연구

문홍득,강경덕,배상범,김남호,Moon Hong-Deuk,Kang Kyeong-Deog,Bae Sang-Bum,Kim Nam-Ho 한국정보통신학회 2004 한국정보통신학회논문지 Vol.8 No.7

영상은 획득, 저장 그리고 전송 등의 처리과정에서 다양한 원인에 의해 훼손되며, 이러한 영상을 복원하기 위한 많은 연구가 이루어지고 있다. 일반적으로 AWGN(additive white gaussian noise)에 의해 훼손된 영상을 복원하는 방법으로 평균 필터와 위너 필터가 있으며, 특히 평탄한 영역에서의 노이즈 제거에 평균 필터가 우수하다. 그러나 평균 필터는 영상의 특징을 고려하지 않으므로 에지 성분이 왜곡되어 평활화되는 단점이 있다. 따라서 본 논문에서는 평균 필터와 함께 에지 성분을 보존하면서 대조도 개선에 강한 위너 필터를 사용하여 각각 필터링한 후, 처리된 영상에 가중치를 설정하여 병렬처리하는 영상 복원 방법을 제안하였다. Image is degraded by several causes such as the process of acquisition, storage and transmission. To restore those images, many researches have been continued. Centrally methods to restore degraded image by AWGN(additive white gaussian noise) a.e mean filter and wiener filter. Especially, mean filter is superior in noise reduction of area that is a small change of luminosity. But mean filter brings about the effect smoothing edge components of the image, because it does'nt consider characteristics of the image. So in this paper we propose an image restoration method compounding respective images adding established weights, after filtering with mean filter and powerful wiener filter in both improvement of contrast and preservation of edge components.

현장계측에 의한 터널 지보재에 작용하는 지반하중 평가 연구

문홍득 진주산업대학교 1998 論文集 Vol.37 No.-

NATN(New Austrian Tunnelling Method) uses a support system of shotcrete, rockbolt, and steel support, which are installed after tunnel excavation. Among these support system, a steel support is used for reinforcement of a unsupported ground, redistribution of the rock load applied to shotcrete, and resistance of the earth pressure until the strength of shotcrete and rockbolt is fully developed. Recently, a H-shaped steel set is reported to have some problems in installation. So, a Lattice girder was developed to replace a problematic H-shaped steel set in Switzerland and German. Lattice girder is a triangular shape welded with steel rods. Lattice girder is a light-weight support system which enables fast installation. The major advantage of lattice girder is the good bonding with shotcrete. To evaluate the applicability of a lattice girder to tunnelling in Korea, field test was performed at a high speed railway tunnelling site with a large section and was compared with the feature of a H-shaped steel set. This paper especially presents the evaluation of the percentage of the rock load distributed to shotcrete and a steel support system(lattice girder and H-shaped steel set) which were investigated in this study. Field tests proved that a lattice girder fully supported the initial earth pressure developed right after tunnelling and therefore limited ground deformation effectively.