탄-소성론에 근거한 콘크리트 3차원 구성모델

박길현,이용학,이용재 한국구조물진단유지관리학회 1997 한국구조물진단학회 학술발표회논문집 Vol.- No.-

시설공사 계약금액 조정제도의 개선방안 연구

박길현,김성주,양승현 朝鮮大學校 建設技術硏究所 2007 建設技術硏究 Vol.27 No.1

As lowest price bidding system is extended recently, over heated construction companies aggravate payability extremely. As, in 2004, government enforce the system of achievement cost of construction to reflect actual contract price, based on standard efficiency per unit, from the system of cost accounting, an anxiety that an earning rate of construction would be deteriorating becomes bigger. There is a necessity to study as people pursue reasonable appliance of law is on the rise and require to improve the system of contract price arbitration resolutely. The reform measure for the system of contract price arbitration is that we should know a reason to use colligating progress schedule and if contractor ask to change blueprint, we should calculate new price based on the time when contractor asks to change in addition that we should integrate counters when we examine contract price. We reach a conclusion that we should not have contractors damaged when we calculate contract price again because of intervention of price fluctuation, blueprint alteration and deletion of items.

RC교량의 외관상태지수가 내하력에 미치는 영향

박길현,황선하 朝鮮大學校 建設技術硏究所 2007 建設技術硏究 Vol.27 No.2

In a regularly intervaled check service, sight checking may not be the best way to check internal problems, but it is a very fit process to examine objectively in a economical point of view. Since sight checking is limited by its quality and quantity, it is necessary to use the small numbers of uncertainties in many different points with our instinct and experiences. Since sight checking is limited by its quality and quantity, it is necessary to use the small numbers of uncertainties in many different points with our instinct and experiences. Because of these certain situations, the condition and the reliability have been evaluated by professional instinct and scientific decisions. Properties of the selected items were standardized with reference to the existing research results and actual data. As for the item that is difficult to represent quantitatively, word variable of the Analytic Hierarchy Process was introduced and standardized so that the objectivity of the subjective valuation was acquired. Results from this study are as followed, It is possible to acquire very reliable appraisal results of the reinforced concrete bridges according to the Analytic Hierarchy Process defined in this study. Result from this study can be applied practically through the application and analysis of the appraisal technique and the procedure with actual data. Verification through the practical uses and improvements are required for the development in this field.

의사결정 방법에 의한 철근콘크리트 구조물의 상태평가

박길현,황선화,유동원 朝鮮大學校 建設技術硏究所 2006 建設技術硏究 Vol.26 No.1

In this study, a method based on the Analytic Hierarchy Process for systematizing the maintenance and securing the safety of the reinforce concrete bridges using an appearance inspection and state evaluation was proposed. It would be possible for general structure engineers to appraise the bridges with this method. Results from periodical inspections are mostly qualitative because of the inspector's subjective judgment. Therefore, for more objectivity of the results from the safety inspections. quantitative standardization processes of the appraisal items areessentially required. Properties of the selected items were standardized with reference to the existing research results and actual data. As for the item thatis difficult to represent quantitatively, word variable of the Analytic Hierarchy Process was introduced and standardized so that the objectivity of the subjective valuation was acquired. Results from this study are as followed. It is possible to acquire very reliable appraisal results of the reinforce concrete bridges according to the Analytic Hierarchy Process defined in this study. Result from this study can be applied practically through the application and analysis of the appraisal technique and the procedure with actual data. Verification through the practical uses and improvements are required for the development in this field.

유한차분법에 의한 여러 斜角의 直交異方性 I 形강보 橋梁의 해석

박길현,옥제남 조선대학교 국토개발연구소 1988 국토개발연구 Vol.8 No.1

Various angles of skewed and rectangular orthotropic bridges are analyzed by finite difference solution which is developed for a general system of skew coordinates on the bridge slab. The finite difference solution provides a means of computing the stress analysis at various mesh points by use of a 16-Bit personnel computer. This computer program can be applicable to any kind of bridges, regardless of bridge length and width, skew angles, traffic lanes and loading, I-Beam size and it's spacing. In this study one used as much as fine mesh points to get more precise answer.

비틀림을 받는 鐵筋콘크리트 部材의 設計에 관한 考察

朴吉鉉,朴正南 조선대학교 국토개발연구소 1980 국토개발연구 Vol.2 No.1

This paper is a study on the design of reinforced concrete that was subjected to torsion. In this paper, the data on the design of concrete members subjected to torsion and bending, torsion and shearing, and combined stress by shearing, which have been studied up to now was checked. And what is thought to be the most adquate of the data was developed and arranged. Finally, an example is given to explain how this can put to practical use.

균열밀도에 따른 RC교량의 내하력 평가 및 수명 예측

박길현,황선화,박종환 朝鮮大學校 建設技術硏究所 2006 建設技術硏究 Vol.26 No.1

There are several causes, the Percussion from the exterior, the decline of capacity by circumstances, the crack occurred in the interior, the carbonation and soon, that can shorten the span of the concreted construction. And crack density of bridge structures gets higher when they are deteriorated because the concrete crack is the problem of usability. Higher crack density cause the higher bending moment and lower load carrying capacity. In this reason, crack investigation was executed to understand the relation among the degree of degradation caused by the crack occurred on reinforced concrete structures and deflections ratio and load carrying capacity. Deflections ratio and decrease percentage of load carrying capacity of the structures were statistcally analyzed when medium crack which has crack width over O.lmm generated. However, the crack itself, as the primary factor of the life-curtailment of concreted construction, is principal and should bring about the erosion of the reinforcing rod and the span of life.

염해손상을 입은 철근콘크리트 구조물의 내구성 증진을 위한 하부대단면 보강공법

박길현,박종환,양승현 朝鮮大學校 建設技術硏究所 2007 建設技術硏究 Vol.27 No.1

This paper deals with the strengthening method for the Increase durability of the reinforced concrete structures with Chloride Damage, and the purpose of this research is to develop the construction method and materials for extending the lower cross-section of the structures which is set up on the sea. Accordingly, a reinforced concrete pier, which has serious damage at the lower cross-section, is adopted as the subject structure for the study. In the cases of repairing or extending the lower cross-section for the structural reinforcement like the matter in this study, the most important component of choosing an method is the adhesion between the boundary sides of the existing and new concrete, and as the operation is taken on the sea, the material and method, which suit to the ocean surroundings and operating condition, should be chosen. The structural properties and operation condition taken into consideration, the material, which causes far less pollutant and have much better adhesion and strength, is developed, and with this material, this study indicates the best strengthening method to minimize the amount of rebound and to prevent the joints from breaking out. The lower cross-section extension work of the subject is executed with the newly-developed material and the method for strengthening, and as a result of the quality inspection, the material and method prove their superiority since the compression, ultimate and adhesion strength of the concrete was huge, and the adhesion between the glass fiber and the section extended is great. As the material and the strengthening method developed in this study bring about little possibilities of polluting the ocean, make it easy to operate on the sea, and have great adhesion not only between the existing and new concrete but also among each mortar layers, they are considered to be very suit to strengthening and extension of the reinforced concrete structure set up on the sea.

鐵筋콘크리트 構造物의 極値設計에 관한 硏究

朴吉鉉 조선대학교 동력자원연구소 1985 動力資源硏究所誌 Vol.7 No.2

The concept of maximum mean largest value introduced by E.J. Gumbel is the design of reinforced concrete structure, and is named as the worst-state design and/or extreme value design. The characteristics of the worst-state design are as follows ; 1) The structure is designed by using minimum material strength and maximum external force. 2) Minimum material strength and maximum external force are derived as the minimum mean smallest value and the maximum mean largest value, respectively, by using Lagrange multiplier under the condition that failure probability of the designed structure is never exceed a certain value in any case. 3) Material strength consists of two independent parameters such as steel rod and concrete. External force consists of two independent parameters such as traffic load and seismic load. In this paper, first, maximum mean largest value is derived by introducing new characteristics A, B, C and d in order to reduce the excessive estimation of the largest value; second, the concept is extended to the estimation of the upper bound value of failure probability; third, the concept is also extended to two parameters problem, where two kinds of material strength and/or two kinds of external force are included; fourth, an example of design of reinforced concrete girder bridge is provided; and fifth, some execution error problems such as location error of steel rod of reinforced concrete girder are discussed.

균열밀도에 따른 R·C 슬래브 교량의 내하력 평가

박길현,양승현,황선하,정경덕 朝鮮大學校 建設技術硏究所 2003 建設技術硏究 Vol.23 No.1

Through the exterior features on reinforced concrete slab, crack density and crack originate deflections ratio crack density, decrease percentage of load carrying capacity, crack originate deflections ration and decrease percentage of load carrying capacity were statistically analyzed. Crack density, crack originate deflections ratio and decrease percentage of load carrying capacity are very closely related each other with 0.724, 0.821 and 0.317 of correlation coefficient within 95% of mind level. However, the correlation between crack originate deflections ratio and decrease percentage of load carrying capacity was low. Through the regression equation curve method in which crack density selected as independent variable, crack originate deflections ratio and decrease percentage of load carrying capacity as dependent variable, regression equations were presumed. Equations exist in mind level range of F(0.05, S-curve showed the highest, conformance with 79.5%, 72.2%. The regression equation between CRD or LCCD and CD was also shown. The overall judgement of load carrying capacity of bridges can be possible through the moreover investigation of crack density, the time needed precision could be valuable data for lower maintenance cost, the degree of deterioration of bridges and safety judgement.