파일 施工時 波動 方程式에 의한 支持力 解析

최영송,송전섭,김팔규 忠南大學校 産業技術硏究所 1990 산업기술연구논문집 Vol.5 No.2

Pile driving is a complex problem to be solved, involving the interaction of the hammer, soil and pile. Recently the wave equation analysis as proposed by Smith has been most frequently used to investigate pile driving caracteristics. The purpose of this work, therefore, is to discuss the case of the wave equation as applied to deep alluvial deposit soil with the help of complete driving and loading test results executed during the construction of the Nakdong Estuary Barrage located at the river mouth of the Nakdong. Comprehensive literature review of the proposed value to inqut parameters have been made to find and propose optimum parameters applicable to this area. For various different value of parameters, of course, within the boundary of valkue found from literature, pile set and total resistance were predicted by using the WEAP.

土木工學敎育科 敎育改善에 關한 硏究

金八圭,鄭海駿,權五憲,姜準默,林熙大 충남대학교 공업교육연구소 1981 論文集 Vol.4 No.1

Korea enters a new era of industrial modernization, spurred by her successive five-year economic development plans. The labor-intensive light industry that led the nation's economy in the past decades is undergoing a gradual shift to the technology-intensive heavy and chemical industry. The demand for industry-minded young technician is thereby ever mounting in number in various industrial sectors, which in turn creates many challenging issues on Civil Engineering Education. Among them, this paper deals exclusively with the curriculum of the Department of Civil Engineering Education. As the results of a trade analysis for graduates from technical high schools, it was realized that current curriculum were somewhat isolated from outside environment and found too rigid to meet the changing requirements. Needless to mention, teachers play a vital roles in the technician education. Accordingly the teacher must be qualified well not only in knowledge on the major subjects but also in practices. The improvement of current curriculum is strongly recommended to produce qualified teachers, taking into account the changing social demands. This study is very limited in terms of finance, time allowance and manpower. Accordingly the model curriculum was based on the trade analysis, social requirements and the current curriculum, and its justification was not verified by tests and broad reviews.

飽和度에 따른 三軸壓縮强度의 特性 硏究

최명진,고영현,상현규,김팔규 忠南大學校 産業技術硏究所 1999 산업기술연구논문집 Vol.14 No.1

Lately,the study of the soil behavior and mainly related to the degree of saturation. But most soils in the ground actually exist not in the saturated condition but in the unsaturated one. The foundation bases adn the soils used for construction material are almost such unsaturated soil as granite soil in Korea. The griaxial test are used in order to examine the strength characters of the unsaturated soil in this research, reappeared in-situ field condition for the undaturated soil through the UU-test in the laboratory and examined strength character. The variation of shear strength accrding to the increase of the degree of saturation is measured as the result and the proposed formula are suggested

CRS 압밀시험속도 산정에 관한 연구

김팔규,류권일,최명진,고영헌 충남대학교 공업교육연구소 2002 論文集 Vol.25 No.1

Even though STD test based on Terzaghi's 1-D consolidation theory is extensively used to estimate the consolidation constant of soft-clay, it takes too much time to perform the test in addition to the problem in estimation of C_v and preconsolidation pressure. To overcome these defects, several types of rapid consolidation test, e.g., Constant Rate of Strain Test (CRS) and Controlled Gradient (CG), are proposed. Because consolidation characteristics obtained from the results of CRS test depend on the rate of rate of strain, it is repuired to determine the variation rate on the basis of the physical and structural characteristic in a building site, and then perform the test. Several methods determining the rate of strain, e.g., ASTM standard, Smith and Wahls' equation in 1969 and Armour and Drnevich's equation in 1986, have been researched. However, the rules about consolidation rates described in ASTM consider only the summary of the rate rules as a trial and error and its criterion also depends only on LL value. In this thesis, the test rate and parameters related in addition to LL value considered on ASTM basis are esamined in many fidlds of view ane the corresponding rate criterion is proposed.

반복하중을 받는 등방정친압밀점토의 거동 및 한계반복응력

김팔규,송전섭 한국지반공학회 1988 대한토질공학회지 Vol.4 No.3

반복하중을 받는 정토의 거동은 단일하중에 의한 결과와 매우 상리하게 나타나며, 그중에서도 특히 간극수려의 거동은 상당히 중요하다. 본 연구는 반복하중 하에서의 점토에 대한 응력-변형 특성을 규명하기 위한 실험적 연구로서 하 중을 가하는 동안에 발생하는 간극수려에 대하여도 언급하였다. 시료는 삼축용기 안에서 24시간동안 등방려밀시켰으며, 삼축시험은 비배수상태 하에서 재성형된 시료에 때하여 압축파괴, 파괴반복, 비파괴 평형시험을 변형제어방법으로 수행하였다. 이에 따라 어느 특정한 시료의 거동을 뚜렷하게 서로 다른 두가지 양상으로 구분하는 반복응력의 한계치가 존재 함을 확인할 수 있었다. The behavior of clays subjected to Repeated loading has been shown to be very different from the behavior under a single load application. Especially the behavior of pore water pressure is Qf considerable importance. The objective of this work is to experimentally study the stress-strain characteristics of clays, and this study includes the pore water pressure which is built up during the load repetition. For this study, the samples were consolidated isotropically in the triaxial cell during 24 hours, .and monotonic strain controlled triaxial test is carried out by uslng the tests of Compression failure, Cycled at failure, and Nonfailure equilibrium on remoulded samples under undrained .condition . Consequently there exists a critical level of repeated loading which seperates the behavior of a particular sample into two distinctly different patterns.

海外 建設 輸出 擴大와 土木敎育 改善方向 : 工高 敎科 課程을 中心으로

金八圭,權五憲,金再韓,姜準默 충남대학교 공업교육연구소 1979 論文集 Vol.2 No.2

The design of a curriculum and its revision, as distinct from a syllabus, is very complex and broad in the scope. Many models for curriculum design and development have already been studied to provide a clear understanding of the curriculum process and to identify the inputs, assessment, validation and feedback. All these diversified models, however can be analyzed using common parameters, including non-industrial components such as entry requirements, attitude, and social needs. The paper strongly recognizes the importance of the social requirements in the curriculum design process as far as the korean technical high school education is concerned in Korea. Consecutive implementation of five year economic development plans. has required tremendous amounts of expenditures to provide infrastructures since the early 1960's. Moreover, the present energy problem contributed to the constructional boom in the middle - east countries. These circumstances spurred the rapid expansion of construction works over the last two decades in korea. The existing curricula of technical high schools were reviewed and found too rigid to meet the changing requirements. In a sense the curricula were isolated from outside environments and the feedback system was not likely to work. The study was very limited in terms of finance, time allowance and manpower. Accordingly the paper does not cover the scope of all activities but analysis of some likely inputs on the basis mainly of returned questionnairs. And the model, curriculum was made based on the statistics of returned questionnairs from industry, educators subject teachers, and government authorities, etc. In comparison with the recommended model curriculum in Japan. the changed social demands, advanced skill and technology, and mechanized and complicated work procedures are analyzed and reflected in the structure of the model curriculum in terms of rearranged and elective subjects, its priority and time allocation. However further studies are urgently recommended to supplemont this study especially in the scope of intensive trade analysis, identification of skilled workers' roles in the job spectrum, assessment and validation scheme and T/L resource development.

Strip Area의 水平應力을 考慮한 深度別 壓密沈下

金八圭,林熙大 충남대학교 공업교육연구소 1980 論文集 Vol.3 No.2

This paper develops new equation for predicting in-situ consolidation settlement at any depth of a Strip Area subject to a Uniform Pressure and describes the laboratory procedures used to validate the equation. In order to calculate consolidation settlement at any depth, the depth of clay layer was divided into n equal parts of thickness Δz and the vertical stress was determined, based on the Boussinesq solution. Prediction of consolidation settlement is normally based on the results of one -dimensional Oedometer tests using representative samples of the clay. Due to the confining ring the net lateral strain in the test specimen is zero but in many practical situations, however, appreciable lateral strain will occur and the initial excess pore pressure will depend on the in -situ stress conditions. Applying the Bussinesq solution and the Skempton -Bjerrum method which took the lateral strain into account, a new equation was derived that can be used to calculate consolidation settlement at any depth for a Strip Area carrying a Uniform Pressure. The equation proved to predict the consolidation settlement at any depth more closely to the actual field conditions than have previously known equation.

압축성 모의 압밀에 대한 수치해석 -다층토를 중심으로-

김팔규,송용희,이환기,Kim, Pal-Gyu,Song, Yong-Hui,Lee, Hwan-Gi 한국지반공학회 1985 대한토질공학회지 Vol.1 No.1

압축성 흙에 대한 천밀침하의 수치해석 연구는 이제까지 Terzaghi의 정밀론을 간단히 확장하여 사용해 왔다. 그러나 비선형 응력-변형관계, 다층토, 큰 변형의 문제를 고려한 보다 복잡한 문제를 탄밀론에 적응한 예는 거의 없었다. 본 연구의 목적은 압축성 흙에서도 다층토를 중심으로 시간과 위치에 따른 추밀도와 과잉간극수압을 보다 실제적인 조건에 부합되도록 하기 위하여 유한차분법을 사용한 수치해석을 근거로 유용한 컴퓨터 알고리즘을 개발하는 데 있다. 압밀식을 해석하는 Explicit Scheme이 전체 깊이에 대한 최적분할 깊이율과 아울러 Operator의 변화에 따른 안정조건과 수고의 관점에서 연구되었다. 침하의 예측에 대해 전통적인 대석과 수식해법이 기초를 둔 개발된 알고리즘으로부터 새로운 알고리즘은 압축성 흙에 있어 전통적인 이론보다 우수한 것으로 판명되었다. Ocassionally it is used for simple extensions of Terzahgi's theory to account for time-depend- tint loading but there is little evidence of application in more complicated consolidation theories that take into account such effects as nonlinear stress.strain, layered systems or large strains. The purpose of this paper provides an efficient computer algorthm based on numerical analysis using finite difference method which account for multi-layered soils to determine the degree of consolidation and excess pore pressures relative to time and positions more realistically. The explicitly scheme of solving the consolidation equations has been investigated from the point of view of the stability conditions and the convergence with variance of the operator as well as to obtain an optimal divided depth ratios of total depth. A comparison of the settlement predictions with both the classical analysis and the algorithm based on numerical analysis indicates that the new algorithm scheme is found to be superior to the classical theory in the layered soils.

분할편 경계내각 수렴에 의한 사면안정 해석

김팔규,김규문 한국지반공학회 1987 대한토질공학회지 Vol.3 No.4

본 논문은 분할법을 이용한 사면안정 해석방법에 환한 것으로서 분학편에 작용하는 내력을 경계면에 연직인 수직내력과 저면에 평행인 경사내력으로 상이하게 가정하여 각각에 대한 해법을 개발하였다. 본 해법에서는 가정으로 인하여 발생되는 내력오차를 변론각전에서 소거하였으며 내력의 작용위치를 결정하므로서 보다 펑밀한 안전률을 구하였다. 해석방법의 타당성 검토를 위해 사면모델을 설정하여 분석한 결과, 본 인법 중 경사내력으로 가정 한희석방법이 보다 합리적이며 타륜함을 입증할 수 있었다. 토한 증존역법의 안전본긱 비교하여 상호관계를 조사하였으며 지뇌계수에 의한 영향도 분석하였다. The purpose of this paper is to develop a method of slope stability analysis, using slice method The direction of interstice forces was assumed in two ways: 1) inclined interslice force parallel to the base of slice, 2) normal interslice force normal to the boundary surface of slice being used in the existing slice method. The deviation from the value of interstice force caused by assumption was removed in the Processing of analysis, and the factor of safety was obtained more accurately by deciding the location of interstice force acting on each slice. More rational validity of the method with inclined interslice force was proved by performing slope stability analyses with both methods. The factor of safety obtained by the proposed method was compared with that by the existing methods, and the influence of seismic coefficient was also analyzed.

이달의 논제 : 소도읍기능화전략

김팔규 대한지방행정공제회 1977 地方行政 Vol.26 No.289