• Title/Summary/Keyword: Settlement rate

검색결과 269건 처리시간 0.03초

연직배수재가 부분 관입된 점토지반의 피압에 따른 압밀 거동에 관한 연구 (A Study of Consolidation Behavior of Clay Ground with Partially Penetrated PVD under Artesian Pressure)

  • 윤대호;;김재홍;김윤태
    • 한국지반신소재학회논문집
    • /
    • 제15권1호
    • /
    • pp.47-57
    • /
    • 2016
  • 부산 낙동강 하구 대심도 연약지반 아래에 피압대수층이 존재한다는 것이 많은 연구자들에 의해 관측되었다. 연약지반에 작용하는 피압은 압밀 속도, 압밀 침하량, 연직배수재의 성능 등에 영향을 줄 수 있다. 따라서 본 연구에서는 피압의 작용 유 무에 따른 연직배수재가 부분 관입된 점토지반의 압밀 거동을 분석하였다. 연구를 수행하기 위해 일차원 대형 컬럼 장비를 이용한 실내실험과 유한요소 해석을 실시하였다. 실험 결과 피압이 작용하는 점토지반의 압밀 침하가 피압이 작용하지 않는 점토지반보다 더 크게 나타났으며, 과잉간극수압의 소산 속도는 더디게 나타났다. 또한 동일한 지반 조건을 이용하여 유한요소해석을 수행한 결과 실내 실험과 유사한 경향을 나타내었다.

철근 이음조정률의 개선을 위한 설계견적 수량과 현장시공 정산 수량의 비교분석 연구 (Comparison of the quantity estimations from the design phase and the settlement quantities of construction field to improve the extra rates of bar splice)

  • 김상연;최보미
    • 토지주택연구
    • /
    • 제8권4호
    • /
    • pp.257-266
    • /
    • 2017
  • LH has been using ultra high strength reinforcing bars (SD500 and SD600), since 2011. Such a change requires an adjustment of the old extra rates of bar splice to reflect use of ultra high strength reinforcing bars, as these rates had been set based on SD400 bars. It is particularly difficult to calculate precisely rebar lap-splice locations for large areas, such as those in apartment buildings. This research aims to adjust the extra rates of bar splice to reflect a reasonable rate; the rebar lap-splice length is not an exact estimation, but instead, an extra rates of bar splice is set and the rebar lap-splice length is increased by 2% (D 10) - 7% (025) depending on the bar size. The subjects of this study are LH apartments undergoing frame construction. We studied the quantity estimations from the design drawings, and analyzed the settlement quantities of construction field. The results of the study revealed that, when each of the quantities are analyzed, consider adjusting the extra rates of bar splice of some rebar to 1% - 3.5%. This was caused by an overuse of reinforcing bars in onsite construction and the use of supporting bars that have not been reflected in the documents, among other reasons. Based on the results of our study, an improvement plan for the current extra rates of bar splice seems to be necessary, cutting or raising the rate depending on the analysis of the data. Through this study, we expect to contribute to the calculation of reasonable construction costs, improvements in the quality of rebar work, and improvements in the capacity of design techniques for apartment buildings.

제대군인 취업에 관한 연구 - 민간기업 취업을 중심으로 - (A Study on Employment of Discharged Military Personnel -Establishment and Management of Private Military Company-)

  • 김기훈
    • 안보군사학연구
    • /
    • 통권9호
    • /
    • pp.283-311
    • /
    • 2011
  • The Republic of Korea, ranked as the 5th military power according to the size of its ground troops, discharges more than 200,000 manpower to the society annually; more than 13,000 of them are officers. The re-employment rate of discharged military personnels, who experience early retirement of 5 to 15 years compared to general public officers, is very low, only amounting to 53.2%. On the other hand, major developed countries exhibit great national scale of effort to take responsibility in helping the settlement of the soldiers who have dedicated their career for their countries. The re-employment rate amounts to 94%. Fully acknowledging such disparity, this paper examines various policies on discharged members support of developed countries, and aims to suggest developmental model on employment support designed for discharged members in the Republic of Korea.

  • PDF

Escherichia coli-Derived Uracil Increases the Antibacterial Activity and Growth Rate of Lactobacillus plantarum

  • Ha, Eun-Mi
    • Journal of Microbiology and Biotechnology
    • /
    • 제26권5호
    • /
    • pp.975-987
    • /
    • 2016
  • Lactobacillus plantarum (L. plantarum) is a representative probiotic. In particular, L. plantarum is the first commensal bacterium to colonize the intestine of infants. For this reason, the initial settlement of L. plantarum can play an important role in determining an infant's health as well as their eventual health status as an adult. In addition, L. plantarum combats pathogenic infections (such as Escherichia coli (E. coli), one of the early pathogenic colonizers in an unhealthy infant gut) by secreting antimicrobial substances. The aim of this research was to determine how L. plantarum combats E. coli infection and why it is a representative probiotic in the intestine. Consequently, this research observed that E. coli releases uracil. L. plantarum specifically recognizes E. coli-derived uracil, which increases the growth rate and production of antimicrobial substance of L. plantarum. In addition, through the inhibitory activity test, this study postulates that the antimicrobial substance is a protein and can be considered a bacteriocin-like substance. Therefore, this research assumes that L. plantarum exerts its antibacterial ability by recognizing E. coli and increasing its growth rate as a result, and this phenomenon could be one of the reasons for L. plantarum settling in the intestine of infants as a beneficial bacterium.

재하속도를 이용한 중간토의 지지력 평가 (Relationships of Loading Rates and Bearing Capacities on Intermediate Soils)

  • 박중배
    • 한국지반공학회지:지반
    • /
    • 제12권4호
    • /
    • pp.101-114
    • /
    • 1996
  • 본 연구는 중간토의 지지력 및 변형특성을 조사하기 위해 원심재하장치(centrifuge)를 이용한 지지력 실험을 시행한 결과이다. 점성토에 비해 투수계수가 비교적 큰 중간토지 반을 대상으로 재하 과정에서 발생하는 배수현상이 지반의 지지력에 미치는 영향을 조사하였다. 그 결과, 재하 속도와 지반의 투수계수와의 관계, 즉 본 연구에서 정의한 상대재하속도와 하중강도의 관계로부터 기존 설계상의 문제점을 지적하였고, 또한 재하속도의 차이에 의해 동일 침하량비에서의 하중강도의 대소관계가 역전하는 현상은 비 배수상태의 재하속도 의존성 뿐만 아니라 재하초기부터 발생하는 부분배수현상에 의한 것임을 재하중에 관측한 과잉간극수압의 거동과 변형거동을 중심으로 증명하였다. 나아가 중간토지반에 있어서 기초폭과 초기 지반응력 상태가 지지력에 미치는 영향을 조사하기 위하여 기초폭과 과압밀비를 변화시켜 중간토지반의 지지력 특성을 조사 하였다.

  • PDF

WTO 반덤핑협정 상 비시장경제 규율에 대한 고찰: 미국의 단일률 적용 관행을 중심으로 (Applicability of the Single Rate Presumption for Non-Market Economies within the Framework of the WTO Anti-Dumping Agreement)

  • 김경화
    • 무역학회지
    • /
    • 제46권4호
    • /
    • pp.113-130
    • /
    • 2021
  • This study aims to analyze the WTO-inconsistent aspects of the single rate presumption of the United States in establishing and imposing anti-dumping duties for non-market economy exporters. By examining the drafting history in the GATT/WTO negotiations and the practice of the single rate presumption for non-market economies by the United States from a comparative perspective, it critically addresses the inherent lack of pertinent disciplines under the framework of the WTO Anti-Dumping Agreement in establishing dumping margins for exporters of non-market economies. The WTO Dispute Settlement Body leaves open the possibility of allowing the investigating authority to consider multiple exporters and the exporting country as a single entity. However, the study argues that it is difficult in practice for the investigating authority to make a single-entity decision in a WTO-consistent manner. The study also finds an incompatibility in the notion between establishing dumping margins for 'individual' exporters and 'non-market economies.' A proper discipline for non-market economies under the multilateral anti-dumping norm needs to be reconsidered in the era of persistent trade conflicts between the United States and China.

CRS시험에 의한 2차압밀계수의 결정방법 제안 (A New Proposed Technique for a Secondary Consolidation Coefficient Based on the Constant Rate of Strain Test)

  • 김형주;이민선;이용주;김대우
    • 한국지반공학회논문집
    • /
    • 제20권8호
    • /
    • pp.113-121
    • /
    • 2004
  • 본 연구는 사전압밀재하공법에 의해 연약지반을 개량시 재하-제하-재재하와 같은 다양한 응력변화에 의한 2차압밀량을 추정하고자, 일정변형률 압밀시험기(CRS)를 응용한 일정재하시험장치(CLR)와 표준압밀시험기를 이용한 단계 재하시험(IL)에 의해 군산점토의 압밀특성을 비교 고찰하였다. 또한 CRS시험 후 임의 팽창시점에서 재재하시 유효과압밀비에 따른 2차압밀특성과 간극비-유효응력-시간관계 등을 파악하였다. 군산점토는 유효 과압밀비가 클수록 팽창량은 크고 2차압밀 침하량은 작게 발생하고 있으며, 일시에 하중 제거 후, 재하하는 경우에서 2차압밀계수 $C'_{\alpha}$ 는 완속제거시 보다 작게 평가되고, 유효 과압밀비가 1.4이상인 경우는 유사한 값을 제시하고 있다. 재재하시 발생되는 전체침하량을 기준으로 한 2차압밀계수 $C"_{\alpha}$는 경과시간에 따라 비선형적으로 증가하나 최종값은 급속제거시와 비교하여 유사한 값을 제시하고 있다. 간극비 변형속도는 재하시간이 증가할수록 유효 과압밀비에 관계없이 2개의 시험 모두 일정한 선형관계이고, 유효 과압밀비가 증가할수록 작게 나타나고 있다.고 있다.

재개발지역의 원주민 세입자 재정착률 제고방안 (An Analysis of the improving of resettlement for original tenant in redevelopment district)

  • 남영우;성상준
    • 한국디지털건축인테리어학회논문집
    • /
    • 제9권2호
    • /
    • pp.57-65
    • /
    • 2009
  • Housing Re-Development business is to improve the environment of old residential area and secure insufficient infrastructure facilities for the public, and to provide housing of fine quality for the individuals and it is taken as an opportunity for the individuals to be able to increase their property. However, it is true that the benefits from the redevelopment has not offered to the original dwellers who has lived there for a long time. This research studies the related systems of the Rental House Redevelopment Supply Service and is to present the schema to raise resettlement rate through the investment on the rate of tenants who chose the rental house and their specific characters. This study is to present the reform measures about the following 3 problems, on the basis of prior theoretical studies which deals with the common factors having low rate to move in the rental house of the tenants. (1) Physical side, the problem of supply structure, which is not appropriate Housing Supply Structure, (2) Psychological side, the problem of socially excluded rental house residents (3) Economical side, low re-settlement rate of tenants caused from the unreasonableness of the estimated rental value. This study presents that the compulsory rental housing supply rate should be changed to the gross area not from the number of households, and the supply of rental houses should correspond to the household size of tenants through prior demand survey. Secondly, it proposes the housing complex layout for intermixing to solve the social problems to allow a housing for sale and rental houses mixing in a building. And it proposes that the rental value should be calculated considering the neighboring value and in the long run, it should be calculated considering the tenants' income instead construction cost estimate. Also, it should be arranged to provide an opportunity to create income through resident welfare center improvement and provide self-sufficiency functions leading residents to participate in the residential area's repairing and maintenances.

  • PDF

Separation Performance of a Low-pressure Hydrocyclone for Suspended Solids in a Recirculating Aquaculture System

  • Lee, Jin-Hwan
    • Fisheries and Aquatic Sciences
    • /
    • 제13권2호
    • /
    • pp.150-156
    • /
    • 2010
  • The separation performance of a low-pressure hydrocyclone (LPH) was evaluated for suspended-solids removal in a recirculating aquaculture system (RAS). The dimensions of the LPH were 335 mm cylinder diameter, 575 mm cylinder height, 60 mm overflow diameter, 50 mm underflow diameter, and $68^{\circ}$ cone angle. The inflow rate varied (400, 600, 800, and 1,000 mL $s^{-1}$) with 25%, 25%, 20%, and 10% of bypass ($R_f$), respectively. The maximum total separation efficiency (Et) and reduced separation efficiency (E't) for suspended solids from the effluent of the second settlement tank (before biofiltration) were 58.9% and 45.2%, respectively, at an inflow rate of 600 mL $s^{-1}$ and 25% of $R_f$. The maximum Et and E't for suspended solids from the water supply channel (after biofiltration) were 24.4% and 16%, respectively, at an inflow rate of 1,000 mL $s^{-1}$ and 10% of $R_f$. The maximum grade efficiency (Ei) was 51.6% for a 300 ${\mu}m$ particle size at an inflow rate of 600 mL $s^{-1}$ with 23% of $R_f$. The maximum reduced grade efficiency (E'i) was 37.6% for a 300 ${\mu}m$ particle size at an inflow rate of 1,000 mL $s^{-1}$ with 11% of $R_f$. The results indicate that the separation performance of the LPH for suspended solids removal was size selective and that maximum removal occurred at particle sizes ranging from 300 to 500 ${\mu}m$.

배수재가 설치된 연약지반의 2차압축을 고려한 축대칭 비선형 압밀해석 (Axisymmetric Nonlinear Consolidation Analysis for Drainage-installed Deposit Considering Secondary Compression)

  • 김윤태
    • 한국지반공학회논문집
    • /
    • 제21권3호
    • /
    • pp.133-140
    • /
    • 2005
  • 연약지반에서 압밀속도를 가속화시키고 설계 전단강도를 얻기 위하여 선행압밀공법과 병행된 연직배수공법이 널리 사용되어 왔다. 본 연구에서는 배수계가 설치된 연약지반에서 압밀과정 동안에 간극비의 감소로 인한 압축성과 투수계수의 변화를 고려할 뿐만 아니라 1차압밀 동안에 유발되는 2차압밀(혹은 크리프)을 고려할 수 있는 축대칭 비선형 압밀이론이 개발되었다. 측대칭 비선형 압밀해석을 위한 수치해석 프로그램, AXICON은 가정 B를 바탕으로 유한차분법을 적용하여 개발되었다. 가정 A를 바탕으로 한 Hansbo의 해석적인 해와 AXICON 해석결과를 비교$\cdot$분석하였다. 또한 Ska-Edeby 시험성토 현장지반에서 관측된 침하량과 간극수압의 계측자료와 비교하였다. 해석결과에 의하면 가정 A는 현장침하량을 일반적으로 과소 평가하며, 가정 B가 논리적으로 타당하다. 또한 제안된 해석 프로그램을 사용하면 실제 현장의 거동을 잘 예측할 수 있다.