• Title/Summary/Keyword: 희생부재

Search Result 9, Processing Time 0.022 seconds

Evaluation of Close-Range Blast Pressure Mitigation using a Sacrificial Member (희생부재를 이용한 근거리 폭파압력 저감 효과)

  • Shim, Chang-Su;Yun, Nu-Ri
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.14 no.1
    • /
    • pp.11-23
    • /
    • 2010
  • A sacrificial member with aluminum foam of excellent energy absorption capacity was proposed for the protection of significant structures. Parametric studies of explicit finite element analyses were performed to investigate the pressure mitigation of close-range air-blasts. The scaled distance of the blast had a range of Z=0.48~0.95 and an empirical blast load function was utilized. The analytical parameters of the aluminum foam were density, thickness and the existence of a cover sheet. Analytical results showed that the transmitted pressure can be controlled to have a similar level of yield values of the foam by using a foam with low density and higher thickness. As the blast load increased, the sacrificial member needed to have higher density and thickness. A cover sheet of the foam clearly showed its effect on the wider distribution of blast pressure. It is necessary to determine the design parameters of sacrificial foams considering different energy dissipation capacities according to the scaled distance.

A Study on Impact Resistance Properties with Composition Materials and Installation Conditions of Protective Panel (방호 패널의 구성 재료 및 설치 조건에 따른 내충격 특성에 관한 연구)

  • Seok, Won-Kyun;Kim, Young-Sun;Lee, Yae-Chan;Nam, Jeong-Soo;Kim, Gyu-Yong
    • Journal of the Korea Institute of Building Construction
    • /
    • v.23 no.6
    • /
    • pp.715-726
    • /
    • 2023
  • This study suggested that protective panels should be installed as sacrificial members as a safety design method for structures with potential explosions such as hydrogen charging stations to minimize direct damage to the structure and have resilience. To this end, the focus of the experiment is on quantitatively evaluating the impact of the structure when the protection panel is installed closely or spaced apart from the structure in a high-speed collision situation of the projectile. The experimental design used steel plates instead of concrete structural members mainly used in the past for excellent reproducibility, and the impact of structural members was compared and analyzed through deformation differences on the back of the steel plate. In addition, the impact of changes in the physical properties of the elastic body used as a separation material for the protective member and the difference in shock wave transmission time according to the protective member and the elastic body on the structural member was investigated.

A Study on the Seismic Performance of Energy-Dissipating Sacrificial Devices for Steel Plate Ginder Bridges (강합성 거더교에 적용된 희생부재형 에너지소산장치의 내진성능에 관한 연구)

  • Cho, Kwang-Il;Gwak, Pil-Bong;Mha, Ho-Seong;Kim, Sang-Hyo
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.11 no.3 s.55
    • /
    • pp.87-96
    • /
    • 2007
  • A new Energy-Dissipating Sacrificial Device (EDSD) is developed for steel plate girders, which can effectively dissipate the energy stored in the structures during seismic actions. To verify the performance of the EDSD, various seismic responses of a sample bridge with the EDSD are analyzed in terms of energy, member forces and deformation. The full scale model tests are conducted to certify the performance of the EDSD when it is applied on existing bridges. Using the improved hysteretic model of the sacrificial member, the seismic analysis for an example bridge is performed. The results show that the proposed EDSD under seismic excitations can significantly decrease the energy stored in the bridge structures and reduce the relative displacements of each superstructure to the ground. The EDSD is also found to function as a structural fuse under strong ground motions, sacrificing itself to absorb the excessive energy. Consequently, economical enhancement of the seismic performance of bridges can be achieved by employing the newly developed energy-dissipating sacrificial device.

Poor Custodial Grandparents' Life Story and Care-giving Experiences of Their Grandchildren (저소득층 조손가족 조부모의 인생이야기와 손자녀 양육경험)

  • Oh, Kyung Seuk
    • Korean Journal of Childcare and Education
    • /
    • v.6 no.3
    • /
    • pp.65-84
    • /
    • 2010
  • This study examined poor custodial grandparents' life story and care-giving experiences of their grandchildren. 8 grandparents were selected and in-depth interview and participant observation method were used. They showed a miserable life from the birth and discriminative experience of the deprivation of educational opportunities as childhood nadir experiences. They showed the regret for their inability as youth/midlife low point and financial difficulty as old life nadir experiences. In terms of care-giving experiences of their grandchildren, they showed non-voluntary care-giving, anxiety for the generational continuation of hardship, and lack of familial assistance. Poor custodial grandparents also used family-centered value, community-based social assistance, and self-assurance through their sacrifice as their adjustment strategy. Several research themes such as the importance of basic trust in childhood, the experience of financial difficulties, the importance of community-based social assistance, and self-assurance through their sacrifice were suggested for further research.

Application of Energy-Dissipating Sacrificial Device(EDSD) for Enhancing Seismic Performance of Bridges (교량의 내진성능 향상을 위한 희생부재형 에너지소산장치(EDSD)의 적용에 관한 연구)

  • Kim, Sang-Hyo;Cho, Kwang-Yil;Kim, Hae-Young
    • Proceedings of the Earthquake Engineering Society of Korea Conference
    • /
    • 2006.03a
    • /
    • pp.445-452
    • /
    • 2006
  • A new Energy-Dissipating Sacrificial Device(EDSD) is proposed, which can effectively dissipate the energy stored in the structures during seismic actions. A mathematical 3-D bridge models and analysis techniques are developed to represent the non-linear behavior of the EDSD, various seismic responses of a sample bridge with the EDSD are analyzed in terms of energy, member forces and deformation using the developed analysis method. And the EDSD is tested and certified it's behavior and stability to apply on exiting bridges. The EDSD can be able to dissipate a large amount of energy and therefore it can prevent the pier's excessive forces under seismic excitations and EDSD and its connected members are also stable. Additionally, the method and guidelines of an optimum EDSD design are proposed in terms of installation method and decision of number of EDSD. The Proposed EDSD under seismic excitations can significantly decrease the excessive storing energy in the bridge structures and reduce the relative displacements of each superstructure to the ground. The EDSD is also found to function as a structural fuse under strong ground motions, sacrificing itself to absorb the excessive energy. Consequently, economical enhancement of the seismic performance of bridges can be achieved by employing the newly developed energy dissipation sacrificial device(EDSD).

  • PDF

Understanding of Blast Resistant Design and Performance Evaluation of a Building designed for Conventional Loads (방폭설계의 이해 및 일반하중에 대해 설계된 건축물의 방폭성능 평가)

  • Hong, Jong-Kook
    • Journal of the Korea institute for structural maintenance and inspection
    • /
    • v.22 no.4
    • /
    • pp.83-90
    • /
    • 2018
  • Considering the increased threats from worldwide terrors and the increased demands on the blast resistant design of commercial buildings, this study is aimed at understanding the basic concept of blast resistant design and evaluating the blast performance with an actual design example. Although there are many differences between earthquake and blast loads, the design concept against both loads is similar in terms of allowing the plastic behavior of a structure and sharing the ductile detailing. Through the blast performance evaluation of a target building provided in this study, it is noted that a well-designed building for the conventional loads can have a certain level of blast resistance. However, this cannot be generalized since the blast load on a structure varies depending on the type of weapon, TNT equivalence, standoff distance, etc. Architectural planning with positioning the sacrificial structure or maintaining a sufficient standoff distance from the expected detonation is the simple and effective way of improving the blast resistance of a building.

Through Monitoring Solution Child Abuse and Children's Rights at Child Care Center (어린이집에서의 아동학대와 아동권리 모니터링을 통한 해결방안)

  • Seo, Jin Seok
    • Convergence Security Journal
    • /
    • v.13 no.2
    • /
    • pp.55-66
    • /
    • 2013
  • Child abuse is urgent and important issue that dominates child's life and influences lifetime. Especially, the children who use the daycare facilities are vulnerable to ill-treatment because of young age, resulting in being serious in after-affect of its abuse. In case of being serious, a child may lead to death. Also, the main agent is absent that will speak for the abused child's injustice and ask for help. Thus, the child abuse has many cases of coming to a close always as children's miserable sacrifice. Hence, the child care center employees will need to recognize a fact that the child abuse is not a private problem within home any more, but a serious crime, and to be confronted by early finding and reporting abuse as a responsible person for report. When the child care center employees fully perform a role as a responsible person for report of child abuse and when the cooperation between child protection service and day care center is properly made after report, the daycare facilities will be able to play a role of child safety network, which protects children of being put in the exclusion.

Factors Affecting the Conflict between Grandparents Raising Grandchildren and Adult Children: Focusing on Grandparents' Characteristics (손자녀 양육 조부모와 자녀와의 갈등에 영향을 미치는 요인: 조부모의 특성을 중심으로)

  • Kim, Mee-hye;Seong, Ki-ok;Paeng, Kyoung-hee;Choi, Hee-jin;Choi, So-young
    • 한국노년학
    • /
    • v.31 no.4
    • /
    • pp.905-923
    • /
    • 2011
  • The purpose of this study is to examine factors affecting the conflict between grandparents raising grandchildren and adult children. The data were based on the panel survey to explore korean retirement and income study conducted by National Pension Service in 2009. For this study, 287 parenting grandparents rearing grandchild are selected from the survey. Included variables are a demographic factor, a economic factor, a caregiving-related factor, a health factor, and a family relationship factor. The data were analyzed using descriptive statistics, t-test, co-relation and logistic regression, with SPSS WIN 18.0 program. The results are as follows: First, when grandparents are male, older, highly educated, having no religion, and unemployed, a conflict with their adult children grows. Second, when grandparents do not have earned income or financial income, but have private income transfers, a conflict with their adult children is high. Third, when grandchildren are younger, there are no caregiving rewards, economic activities suspension or reduction because of caregiving, a conflict with their adult children is strong. Also, when grandparents' physical health is good, but their mental health is poor, a conflict with their adult children increases. Fourth, when grandparents' satisfactions with family relationship and spouse relationship are low, but their satisfaction with adult children relationship is high, a conflict with their adult children rises. This study suggests that unlike in the past, grandparents raising grandchildren can no longer make sacrifice themselves for their adult children, but they expect proper exchange between parents and children. Therefore, there needs to be understanding of grandparents raising grandchildren and further studies of a conflict between grandparents raising grandchildren their adult children.

A Study on the Religiosity of Filial Piety Ethics in Daesoonjinrihoe (대순진리회의 효 윤리에 나타난 종교성 연구)

  • Cha, Seon-keun
    • Journal of the Daesoon Academy of Sciences
    • /
    • v.27
    • /
    • pp.171-200
    • /
    • 2016
  • This paper will analyze the filial piety based ethics of Daesoonjinrihoe (大巡眞理會) and the traditional filial piety of Confucianism (儒敎), Buddhism (佛敎) and Taoism (道敎) through comparing and contrasting their unique systems. The traditional Korean ethics regarding filial piety are in great need of reformation as the relationship between the parents and children should not be vertical or unilateral but parallel and reciprocal. However, there have not been sufficient in-depth studies on this specific ideology and alternative approaches. Regarding this prospect, one representative Korean indigenous new religion, Daesoonjinrihoe has emerged and directly engages in the collision between traditionalism and modernity. The modernity of Daesoonjinrihoe, enables the observation of how the filial piety based ethics have developed within a system of doctrine and thereby provides an exemplary model of traditional filial piety reimagined in accordance with modern sensibilities. A brief summary of comparative findings is as follows: First, Daesoonjinrihoe and Confucianism have taken serving parents with respect as an ethic within filial piety, but Confucianism engenders this ideal through the unilateral and unconditional sacrifice of younger people based on patriarchal feudalism whereas Daesoonjinrihoe has rejected such unilateral sacrifice and instead promotes mutual beneficience between parents and children. This difference occurs, in part, due to the filial piety of Confucianism rising in the midst of the feudal order whereas the ideology of Daesoonjinrihoe contains ideals such as "the reciprocation of favor for mutual beneficence (報恩相生)" and "respect for humanity (人尊)," both of which serve as key principles of the new religious world as envisioned by Daesoonjinrihoe. Second, filial piety in Buddhism and Taoism tends to be passive and inactive and is often expressed by praying for happiness and longevity for one's parents while they are alive and later praying for the heavenly rebirth of one's parents after they die. The filial piety of Daesoonjinrihoe also partially contains such ideas, however; they are extended much further and arrive upon novel and profound expressions. The spectrum of the filial piety in Daesoonjinrihoe expands to the extent children perform actions to resolve their parent's sins and pave a new road for their parents. This filial piety requires a cultivation practice from both parents and children. This system of dual cultivation was established because the world-view of Daesoonjinrihoe enables both parents and children to enjoy happiness and wealth both of which are achieved through the completion of religious objectives following cultivation practice. Third, Confucianism and Daesoonjinrihoe hold memorial services for ancestors with sincerity as an expression of filial piety. Filial piety in the Confucian context excludes ideas from Shamanism and thereby memorial services are held for impersonal entities, however; in the Daesoonjinrihoe context, memorial services are held for personal-entities. Accordingly, holding a memorial service for ancestors with sincerity has a greater sense of realism in Daesoonjinrihoe than it does in Confucianism. Fourth, while Confucianism and Daesoonjinrihoe both aim to requite the grace received from ancestors, the contents of grace and reciprocation of favors (報恩) are viewed differently. In Confucianism, since the ancestors existed previously and bestowed the gift of life to their children and indirectly, all of their descendents. Therefore, memorial services for ancestors are held to convey gratitude and filial piety. However, in Daesoonjinrihoe, ancestors not only bestowed the gift of earthly life to their descendents, in the spirit realm, ancestral spirits also spend sixty years accumulating the merit necessary to imbue each of their descendents with spiritual insight. Consequently, filial piety is expressed through memorial services as well as spiritual cultivation. Fifth, in Confucianism, achieving the fame and prestige indicative of success in the mundane world can be an act of filial piety as it would bring pride to one's ancestors, but in Daesoonjinrihoe, succeeding in religious objectives through spiritual cultivation is considered to be a higher form of filial piety. Sixth, Confucianism, Buddhism and Taoism all observe filial piety as system of familial ethics based in morality. This is likewise true of Daesoonjinrihoe, however; Daesoonjinrihoe confers greater importance on filial piety as an essential form of ethics for religious redemption. This is due to the Daesoon interpretation that the absence of filial piety was the direct cause which led to the sickened state of the world and its collapse. Forgetting the grace of parents who have given the gift of life or the grace of ancestral spirits who have accumulated merit on behalf of their descendents are acts of ingratitude which are unacceptable during the period of Reordering of the Universe. Judging from these findings, Daesoonjinrihoe embraces parts of traditional filial piety as it exists in Confucianism, Buddhism and Taoism, but it does so on the ground of its own unique culture. Through re-interpretation and re-creation, ideas regarding filial piety are being further developed. Namely, filial piety in Daesoonjinrihoe is regulations founded upon the reciprocation of favors for mutual beneficence and respect for humanity. Therefore, it is understood as a concept wherein one's own cultivation practice is performed in order to reach religious objectives, the perfection of personal character, and spiritual insight. This requires that even recipents of filial piety (i.e., parents) perform certain cultivation practices to enjoy happiness and wealth. Additionally, filial piety in Daesoonjinrihoe manifests a reinforced religious character and also serves as a system ethics which is soteriologically essential for salvation during the period known as the Reordering of the Universe.