• Title/Summary/Keyword: UHP technology

Search Result 9, Processing Time 0.024 seconds

Conceptual design of ultra-high performance fiber reinforced concrete nuclear waste container

  • Othman, H.;Sabrah, T.;Marzouk, H.
    • Nuclear Engineering and Technology
    • /
    • v.51 no.2
    • /
    • pp.588-599
    • /
    • 2019
  • This research presents a structural design of high-level waste (HLW) container using ultra-high performance fiber reinforced concrete (UHP-FRC) material. The proposed design aims to overcome the drawbacks of the existing concrete containers which are heavy, difficult to fabricate, and expensive. In this study, the dry storage container (DSC) that commonly used at Canadian Nuclear facilities is selected to present the proposed design. The design has been performed such that the new UHP-FRC alternative has a structural stiffness equivalent to the existing steel-concrete-steel container under various loading scenarios. Size optimization technique is used with the aim of maximizing stiffness, and minimizing the cost while satisfying both the design stresses and construction requirements. Then, the integrity of the new design has been evaluated against accidental drop-impact events based on realistic drop scenarios. The optimization results showed: the stiffness of the UHP-FRC container (300 mm wall thick) is being in the range of 1.35-1.75 times the stiffness of existing DSC (550 mm wall thick). The use of UHP-FRC leads to decrease the container weight by more than 60%. The UHP-FRC container showed a significant enhancement in performance in comparison to the existing DSC design under considered accidental drop impact scenarios.

Efficacy of supplementary cementitious material and hybrid fiber to develop the ultra high performance hybrid fiber reinforced concrete

  • Sharma, Raju;Bansal, Prem Pal
    • Advances in concrete construction
    • /
    • v.8 no.1
    • /
    • pp.21-31
    • /
    • 2019
  • The rich recipe of ultra high performance concrete (UHPC) offers the higher mechanical, durability and dense microstructure property. The variable like cement/sand ratio, amount of supplementary cementitious material, water/binder ratio, amount of fiber etc. alters the UHPC hardened properties to any extent. Therefore, to understand the effects of these variables on the performance of UHPC, inevitably a stage-wise development is required. In the present experimental study, the effect of sand/cement ratio, the addition of finer material (fly ash and quartz powder) and, hybrid fiber on the fresh, compressive and microstructural property of UHPC is evaluated. The experiment is conducted in three phases; the first phase evaluates the flow value and strength attainment of ingredients, the second phase evaluates the efficiency of finer materials (fly ash and quartz powder) to develop the UHPC and the third phase evaluate the effect of hybrid fiber on the flow value and strength of ultra high performance hybrid fiber reinforced concrete (UHP-HFRC). It has been seen that the addition of fly ash improves the flow value and compressive strength of UHPC as compared to quartz powder. Further, the usage of hybrid fiber in fly ash contained matrix decreases the flow value and improves the strength of the UHP-HFRC matrix. The dense interface between matrix and fiber and, a higher amount of calcium silicate hydrate (CSH) in fly ash contained UHP-HFRC is revealed by SEM and XRD respectively. The dense interface (bond between the fiber and the UHPC matrix) and the higher CSH formation are the reason for the improvement in the compressive strength of fly ash based UHP-HFRC. The differential thermal analysis (DTA/TGA) shows the similar type of mass loss pattern, however, the amount of mass loss differs in fly ash and quartz powder contained UHP-HFRC.

An Analysis of ICT education status and Policy Proposals for the enhancement of female ability in developing countries - focused on UHP in Indonesia (개발도상국의 여성능력향상을 위한 ICT교육현황분석 및 정책 제언 - 인도네시아 UHP 대학을 중심으로)

  • Park, Hwa-Jin
    • Journal of Digital Contents Society
    • /
    • v.19 no.2
    • /
    • pp.285-292
    • /
    • 2018
  • Though the latest ICT technology is expected to serve as a bridgehead for future industrial development as the core of the 4th Industrial Revolution, the gap in ICT technology is still directly connected to the disparity in wealth and it is widening. Training to foster female ICT capabilities in developing countries is an opportunity to foster quality workforce for national development and a means to close the technology gap. The study aims to investigate the status of infrastructure and ICT education at UHP University in Indonesia, as a preparation for educating students in developing countries with ICT skills. Based on this survey, we develop appropriate ICT education contents for female students and provide necessary policies for ongoing education. We will seek ways to improve efficiency in education by comparing and analyzing the results of the previous research, Life University survey.

Seismic retrofitting and fragility for damaged RC beam-column joints using UHP-HFRC

  • Trishna, Choudhury;Prem P., Bansal
    • Earthquakes and Structures
    • /
    • v.23 no.5
    • /
    • pp.463-472
    • /
    • 2022
  • Reinforced concrete (RC) beam column joints (BCJ) have mostly exhibited poor seismic performance during several past earthquakes, typically due to the poor-quality concrete or lack of reinforcement detailing typical of pre-code design practice. The present study is motivated towards numerical simulation and seismic fragility assessment of one such RC-BCJ. The BCJ is loaded to failure and strengthened using Ultra High Performance-Hybrid Fiber Reinforced Concrete (UHP-HFRC) jacketing. The strengthening is performed for four different BCJ specimens, each representing an intermediate damage state before collapse. viz., slight, moderate, severe, and collapse. From the numerical simulation of all the BCJ specimens, an attempt is made to correlate different modelling and design parameters of the BC joint with respect to the damage states. In addition, seismic fragility analysis of the original as well as the retrofitted damaged BCJ specimens show the relative enhancement achieved in each case.

Textural Characteristics and Bacterial Reduction in Glutinous Rice and Brown Rice Pretreated with Ultra-High Pressure (초고압 전처리한 찹쌀과 현미의 텍스처 특성과 세균 저감 효과)

  • Cheon, HeeSoon;Lim, Taehwan;Cho, Won-Il;Hwang, Keum Taek
    • Korean Journal of Food Science and Technology
    • /
    • v.48 no.1
    • /
    • pp.92-95
    • /
    • 2016
  • Ultra-high pressure (UHP) was applied to glutinous rice (Dongjin) and brown rice (Shindongjin) to determine its effects on the textural characteristics of cooked rice and bacterial reduction in uncooked rice. Hardness and stickiness of the cooked glutinous and brown rice pretreated with 500 MPa for 5 min were significantly attenuated compared to that of the control rice (p<0.05). After the UHP treatment, particles of the glutinous and brown rice were observed to be finer when cross sections of the rice were analyzed using field emission scanning electron microscope. The total bacterial count in the brown rice treated with 600 MPa for 5 min was reduced from $10^7CFU/g$ to $10^4CFU/g$, while the number of thermoduric bacteria in the brown rice was not significantly different after the UHP treatment. These results suggest that UHP may be an effective method for improving texture of dried rice and to reduce bacterial count in raw rice.

Analysis for Internal Flow of Tube on the Self Inflating Tire Using the FSI Method (FSI 기법을 이용한 Self Inflating Tire의 펌핑 튜브 내부 유동 해석)

  • Kim, Myeongjun;Seong, Inchul;Hwang, Inkyeong;Park, Taewon
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.24 no.6
    • /
    • pp.660-667
    • /
    • 2016
  • Maintaining proper tire air pressure is an essential element in ensuring vehicle safety. UHP Tires that boast of many safety features are increasing in the market. In particular, the development of "Self-Inflating Tire" technology is accelerating around the globe. Self-inflating tire refers to a technique for maintaining appropriate tire pressure. An internal regulator senses when tire inflation pressure has dropped below the set air pressure. The tire boosts air through the valve when rolling and compressed air enters into the tire. This procedure keeps the tire air pressure at an appropriate level and increases tire safety. Flow analysis of the internal tube is required to examine self-inflating tires. In this study, a method of tube flow analysis using the FSI Method is proposed. The valve system is also implemented to optimize the regulator and sensor.

DPR System for Projection Displays - Today and Tomorrow

  • Li, Kenneth
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.667-669
    • /
    • 2008
  • With the advancements or LEDs and lasers in projection display applications, arc lamps still provide the most cost effective solution to high brightness display systems. When will arc lamps become obsolete, will be of great importance today and tomorrow? Given the fact that traditional elliptical and parabolic reflectors had been around for decades; Wavien's new dual paraboloid reflector (DPR) technology with its unique imaging property enhances various aspects of the arc lamp performance will shed some light to this question. In this talk, various applications that are feasible today and anticipated needs of tomorrow will be presented.

  • PDF

Critical Aspects in Adoption of Ultra High Pressure Technology for Food Processing - An Overviews (식품가공분야에서 초고압 기술의 이용에 대한 고찰)

  • Jayaprakasha, H. M.;Yoon, Y.C.;Brueckner, H.
    • Food Science of Animal Resources
    • /
    • v.20 no.1
    • /
    • pp.44-55
    • /
    • 2000
  • 신선한 품질의 식품에 대한 수요가 증가함에 따라 열처리의 대체수단으로 이용하기 위한 고압기술의 전망이 밝다. 압력을 이용하여 가공된 과일 쥬스와 잼이 이미 일본시장에 출시되고 있다. 전세계적으로 다른 식품의 안전을 위해서도 이 기술에 대한 개발노력이 진행중이다. 압력과 열, 시간의 복합효과에 대한 이해는 식품의 안정성에 대한 이 기술의 이용 가능성을 더해준다. 효소의 비활성화와 미생물의 사멸을 위한 압력과 시간의 의존도에 대한 상세한 연구는 식품저장에 초고압기술을 활용하는데 있어 매우 중요하다. 에너지 비용을 절감하기 위한 설계의 개선과 여러 식품성분의 변화에 대한 이해는 이 기술의 응용에 큰 도움이 될 것이다. 안전성과 저장성이 높은 신선한 식품을 생산할 수 있는 초고압 기술은 곧 광범위하게 이용될 전망이다.

  • PDF

A Study on the Friction of Tire Tread Rubber using High-Speed Friction Test Machine (고속 마찰 특성 평가시험기 개발을 통한 타이어 트레드 고무의 마찰에 관한 연구)

  • Lee, Jin Koo;Lee, Dong Ju
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.30 no.6
    • /
    • pp.622-628
    • /
    • 2013
  • Due to the development of compounding technology, there is a considerable increase in the number of high performance rubbers in the world. Accordingly, there are rapid growing requests about high performance tires such as UHP tire and Run-flat tire. However, it is extremely difficult to investigate the friction coefficient of tire tread rubbers. An alternative solution must be developed with the reliability of high-speed linear friction test machines. The use of friction test machines can be expected to improve rubber friction researches. In this paper, we propose a new kind of high-speed linear friction test machine. We have designed and manufactured various mechanisms for friction tests. The final goals are to design and manufacture friction test machines that can investigate friction coefficients efficiently and rapidly. The performance of the proposed high-speed linear friction test machine is evaluated experimentally; however additional study should be necessary for safer and more reliable experimentation.