• 한국터널공학회:학술대회논문집
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• 한국터널공학회 2005년도 학술발표회 논문집
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• pp.270-281
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• 2005

An especial attention for old tunnel safety is required on increasing of The various tunnel recently. Specially, the lining investigation method of the old tunnel will be able to presume condition of concrete lining indirectly. Because it is many restriction thought of environment and ground condition investigation method of tunnel lining rear. This study carried out section & convergence measurement of part which was deformed in tunnel lining. It had been observed for the change of tunnel behavior with a continuous measurement. It has been analyzed for a cause of tunnel deformation and inspected for the effect after a repair-reinforcement to tunnel compared with the effect before those by structure analysis. By establishing automatic measurement system after repair-reinforcement to tunnel, it would be accomplished to convergence measurement continually. As a result, it was observed that deflection and deformation of tunnel was convergent. but it should be followed to a continuous maintenance because of unstable ground condition, cause of inner tunnel, environment. The railroad tunnel which was executed a reinforcement of the tunnel lining must investigate the close condition of reinforcement lining and concrete lining.

• 가정과삶의질연구
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• 제3권1호
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• pp.107-125
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• 1985

This paper investigated adult's consciousness with a view to establishing basic data about set-up any concrete plan and provision for elderly life in hoe and society. In this paper, the study of concerned reference and social survey by questionnaire are used. The data is obtained from 326 espondents who are 30 to 4 years old in Seoul and Andong. As to consciousness to the provision for elderly life and situation of set-up any concrete plan, the x2(chi-square) is applied to the analysis of regional, socio-economical, demographic difference. The conclusion of this study are as follows; 1) Although the respondents show positive attitude toward consciousness to the provision for elderly. life, their behavior does not show any sing of translating it into reality. 2) The consciousness to the provision for elderly life varies according to regional, socio-economical, demographic variance. Those who are in their 30's more-educated, and high-income want to be more independent from their children and express strong desire to set-up provision for elderly life in advance. This is also true of those living in city. As a results, as adults(30-54) recognize the importance of provision for elderly life, so the support by the society or governmental policy for the solution of better-life for old people is important. however, mental , physical, economical preparation in family life according to the family life cycle can basic solution.

• 토지주택연구
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• 제5권3호
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• pp.123-129
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• 2014

Paris hasn't experienced such excitement since the huge changes brought about by Baron Haussmann in the 19th century. Paris Rive Gauche project, started in 1991, is the largest urban project in city ever since, it represents about 1% of Paris territory. It takes place on a workshops, factories and warehouses area that prospered along the Seine river and the railways in the 19th century. Originally planned as a business quarter, Paris Rive Gauche, developed by SEMAPA for the City of Paris, fosters urban diversity through housing, offices, public facilities, shops, creating a stimulating neighbourhood where 18,000 residents, 30,000 students as well as 60,000 employees will soon croth paths. This project's main principles are urban and social diversity, deployment of public facilites, the development of new university campus inside the city, promotion of industrial patrimony and connecting the old 13th distict to the river and the opposite side. Half of the project is going to be built on a concrete slab that covers the railway tracks which is one of the major performances of this long-term project. This concrete slab represents the new level of the City, about 6 to 8 meters above the railway tracks. We distinguish three families of buildings on the cover : Classic buildings; Bridges buildings and Connection buildings, these last guarantee the linkage between old and new level of the City.

• 콘크리트학회논문집
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• 제29권4호
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• pp.407-413
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• 2017

본 연구는 콘크리트 보수재료로서의 MgO계 세라믹(Magnesia Phosphate Cement: MPC) 모르타르의 기초물성 평가를 위한 것이다. 이를 위해 응결시간, 압축강도, 부착강도를 측정하였으며 수화물의 측정을 위해 X-ray 회절분석을 실시하였다. 시편은 중질 마그네시아(dead burnt magnesia)를 바인더로 사용하였으며 활성제로 칼륨계 인산염을 사용하였고, 응결시간을 지연 시키기 위해 Borax를 지연제로 사용하였다. 또한, 이온침투저항성 평가를 위해 공극구조와 촉진염화물침투시험을 실시하였다. 그 결과 MPC 모르타르의 응결시간은 M/P 비에 따라 16~21분 사이로 빠르게 경화하였으며 지연제인 Borax는 MPC의 응결시간을 68분까지 늦추는 데 도움이 되었다. MPC 모르타르의 압축 강도는 12시간 재령에서 M/P 비에 따라 11.0~30.0 MPa 범위로 발현되었고 특히 M/P 비가 4인 MPC의 압축 강도는 12시간 이내에 30 MPa 정도의 강도를 발현하였다. MPC의 인장 부착강도와 휨 부착강도는 OPC 모르타르에 비해 각각 19 MPa와 17 MPa로 더 높게 측정되었으며 MPC 모르타르의 총 공극량은 OPC 모르타르에 비해 적게 측정되었고 촉진염화물침투시험에서도 MPC 모르타르를 통과한 총 전하가 OPC 모르타르보다 적었으며 이는 공극량과 공극분포로 설명 할 수 있다.

• 한국지진공학회논문집
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• 제8권4호
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• pp.43-50
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• 2004

일반적으로 콘크리트댐은 비파괴 검사를 실시한 물성값을 이용하여 정적 및 동적 안전성 평가를 실시한다. 그러나 이런 값을 이용하여 수치해석을 할 경우 경험적인 물성값을 적용하기 때문에 안전성 평가에 대한 결과는 현실적 요소를 반영하기 어렵다. 또한 댐은 품질관리가 중요한 요소 중 하나이지만, 과거 건설된 몇몇 댐에 대해서 축조시기, 타설시기가 달라 재료적 특성에 따른 안전성 문제가 대두되어 관심이 되었다. 따라서, 본 연구에서는 오랜기간 동안 건설중단 된 후 완공된 콘크리트댐의 내부상태를 조사하고(BIPS), 시추코아에 대한 물리특성 실험을 실시하여 물성값 차이로 인해 발생되는 동적특성 결과를 비교분석하였다.

• Structural Engineering and Mechanics
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• 제4권3호
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• pp.257-276
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• 1996

In North America, a large number of concrete old slab-on-steel girder bridges, classified noncomposite, were built without any mechanic connections. The stablizing effect due to slab/girder interface contact and friction on the steel girders was totally neglected in practice. Experimental results indicate that this effect can lead to a significant underestimation of the load-carrying capacity of these bridges. In this paper, the two major components-concrete slab and steel girders, are treat as two deformable bodies in contact. A finite element procedure with considering the effect of friction and contact for the analysis of concrete slab-on-steel girder bridges is presented. The interface friction phenomenon and finite element formulation are described using an updated configuration under large deformations to account for the influence of any possible kinematic motions on the interface boundary conditions. The constitutive model for frictional contact are considered as slip work-dependent to account for the irreversible nature of friction forces and degradation of interface shear resistance. The proposed procedure is further validated by experimental bridge models.

• 복식문화연구
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• 제8권5호
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• pp.754-770
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• 2000

The definite objects of this study are as follows ; 1. The study presents concrete objects of the shape of adult women's neck and shoulder after comparing and analyzing the features of five age groups ; the former young age, the latter young age, the former middle age, the latter middle age, the latter middle age and the old age. 2. The study presents concrete objects of adult women's neck and shoulder by the body types ; bend-forward type, straight type and lean-back type in order to be examined the body types. The results of this study are as follows ; 1. The shape of neck and shoulder needs the several concrete objects of each types because of the variable factors in size and body types. But the concrete objects of the types referred in five age groups contain all the important factors and enable to design the body suitable clothes. 2. This study shows that generally bend-forward type contains rising shoulder and lean-back type contains drooping shoulder, and straight type contains average value of neck and shoulder. The results of this study developed the body-suitable clothes of bend-forward type, straight type and lean-back type.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 추계 학술논문 발표대회
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• pp.179-182
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• 2009

Concrete containing styrene-butadiene latex is widely used, nowadays, as a protective system for bridge. Latex modification mortar have taken advantage of latex modification concrete advantage that is used in existing, Also, when repair, protection and sticking performance of concrete overlay waterproof agent were known as that are good. Replace and experimented from fine aggregate to recycled aggregate to secure economic performance than existing latex modification concrete. Recycled fine aggregate has low quality because it contains large amount of old mortar. So, its usage is limited to a lower value-add, such as the roadbed material etc. This study is purposed to improve the performance of mortar made of recycled fine aggregate. For this, recycled aggregate mortar was produced with latex, and fluidity, strength were examined. Test result indicate that mortar using recycled fine aggregate is higher compressive and flexural strength than mortar using river sand.

• Advances in concrete construction
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• 제10권3호
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• pp.221-236
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• 2020

To reduce the CO₂ emissions associated with the manufacture of portland cement (PC), an efficient alternative like an alkali-activated binder (AAB) is the requirement of the industry. To promote the use of AAB in construction activities, a practically implementable mix proportion is required. Owing to the several raw ingredients of AAB concrete and their associated uncertainties, partial replacement of PC by AAB may be adopted instead of complete replacement as per industrial requirements. Hence, the present study aims to determine an optimal proportion for partial replacement of PC with AAB and recommend a technique for it based on site conditions. Three modes of partial replacement are followed: combining all the dry ingredients for AAB and PC followed by the addition of the requisite liquids (PAM); combining the PC and the AAB concrete in two horizontal layers (PAH); and two vertical layers (PAV). 28-day old specimens are exposed to 10% v/v solutions of HCl, H₂SO₄, and HNO₃ to evaluate changes in mechanical, physical, and microstructural characteristics through compressive strength, corrosion depth, and microscopy. Based on deterioration in strength and integrity, PAH or PAV can be adopted in absence of acid attack, whereas PAM is recommended in presence of acid attack.

• Earthquakes and Structures
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• 제17권4호
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• pp.337-354
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• 2019

This paper presents the results of experimental and numerical studies conducted to investigate the behavior of exterior reinforced concrete beam column joints (BCJ) strengthened by using carbon fiber reinforced polymer (CFRP) sheets. Twelve reinforced concrete beam-column joints (BCJ) were tested in an experimental program by simulating the joints in seismically deficient old buildings. One group of BCJs was designed to fail in flexure at the BCJ interface, and the second group was designed to ensure joint shear failure. One specimen in each set was -retrofitted with CFRP sheet wrapped diagonally around the joint. The specimens were subjected to both monotonic and cyclic loading up to failure. 3D finite element simulation of the BCJs tested in the experimental program was carried out using the software ABAQUS, adopting the damage plasticity model (CDP) for concrete. The experimental results showed that retrofitting of the shear deficient, BCJs by CFRP sheets enhanced the strength and ductility and the failure mode changed from shear failure in the joints to the desired flexural failure in the beam segment. The FE simulation of BCJs showed a good agreement with the experimental results, which indicated that the CDP model could be used to model the problems of the monotonic and cyclic loading of beam-column reinforced concrete joints.