• 콘크리트학회논문집
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• 제12권4호
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• pp.59-67
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• 2000

With increased height of structure, the effect of column shortening need special consideration in the design and construction of high-rise buildings. The shortening of each column affects nonstructural members such as partitions, cladding, and M/E systems, which are not designed to carry gravity forces. The slabs and beams will tilt due to the cumulative differential shortening of adeacent vertical members. The main purpose of estimating the total shortening of vertical structural member is to compensate the differential shortening between adeacent members. This paper presents effect of parameters for phenomenon of column shortening in vertical members. The paper presents effect of parameters for phenomenon of column shortening in vertical members. The conclusions obtained from this study are follow as ; Strength of concrete and steel ratio effected on column shortening caused by elastic and inelastic shortening. Also, it is known that Ultimate-shrinkage-Value, Specific-Creep-Value, and volume to surface ratio effected on inelastic shortening only. Particularly, Ultimate-Shrinkage-Value and Specific-Creep-Value effected considerable on the amount of total column shortening.

• 동아시아식생활학회지
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• 제21권6호
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• pp.905-910
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• 2011

Cookies were prepared using different fat: butter, margarine, and shortening. Density, specific gravity of the dough, moisture content, spreadability, color, texture, and sensory evaluation for each cookies were conducted. Density, specific gravity and moisture content of each cookies showed the highest value with butter dough, and the lowest value with shortening dough. Spreadability of the cookie with margarine was the highest, and the cookie with butter and shortening resulted lower than that. The chromaticity 'L' and 'b' with butter cookie appeared the highest value, and margarine cookie and shortening cookie were followed that result. But chromaticity 'a' of butter cookie showed the lowest result while margarine cookie, and shortening cookie showed the highest value. Overall sensory evaluation showed high preference for butter cookie, beside margarine cookie and shortening cookie showed lower preference. Butter cookie was preferred in hardness, brittleness, color and chewiness, over margarine or shortening cookie. Flavor and sweetness with margarine cookie was preferred rather than butter cookie and shortening cookie. Softness and fatty taste of shortening cookie showed the highest result, beside margarine cookie and butter cookie showed lower result.

• The Korean Journal of Physiology
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• 제28권1호
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• pp.61-70
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• 1994

A new method is used to record the actual shortening produced during the auxotonic activity of the sartorius (SAR), gastrocnemius (CAS) and rectus abdominis (RAB) muscles of a lizard Uromastix. The auxotonic twitch and tetanus records thus obtained were used for the first time to calculate the coefficient of linear shortening (COLS). This coefficient represent the relative Index between change in length $(\Delta\;L=L_0-L_1)$ and tension $({\Delta}P\;P_0-P_1)$ due to shortening at the steepest rising phase of the twitch and tetanus, recorded at resting length. In addition to this, maximum shortening $(S_{max})$ and auxotonic tensions were also determined at resting lengths of these muscles. The COLS was found to express the speed of shortening and auxotonic tensions are suggested to be of value to express the internal architecture of SAR, GAS & RAB muscles. The results are discussed in terms of contractile and elastic elements of the muscles alongwith the importance of shortening at resting lengths in skeletal muscles.

• 국제초고층학회논문집
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• 제6권1호
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• pp.91-99
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• 2017

Special consideration should be given to differential column shortening during the design and construction of a tall building to mitigate the adverse effects caused by such shortening. The effects of the outrigger - which is conventionally used to increase the lateral stiffness of a tall building - on the differential shortening are investigated in this study. Three analysis models, a constant-section, constant-stress, and general model, are prepared, and the differential shortenings of these models with and without the outrigger are compared. The effects of connection time, sectional area, and location of the outrigger on the differential shortening are studied. The sectional area of the outrigger shows a non-linear relation in reducing the maximum differential shortening. The optimum locations of the single and dual outriggers are investigated by an exhaustive search method, and it is confirmed that a global optimum location exists. This study shows that the outrigger can be utilized to reduce the differential shortening between the interior core wall and the perimeter columns as well as to reduce the lateral displacements due to wind or earthquake loads.

• 한국지진공학회논문집
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• 제1권3호
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• pp.59-68
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• 1997

대도시에서 초고층 건물의 필요성은 구조 기술자에게 새로운 문제를 안겨주었다. 기둥축소의 효과는 설계 및 시공에 있어 특별한 주의를 요구한다. 기둥의 축소는 칸막이, 마감, 그리고 설비체계와 같이 수직하중을 지탱하도록 고려되어 있지 않은 비구조적인 요소에 영향을 미친다. 또한 각 기둥의 축소량 차이는 주위의 슬래브 및 보와 같은 부재들을 경사지게 한다. 축소량을 예측하는 목적은 부등 축소량의 차이를 미리 보정하는데 있다. 본 연구는 부동 축소량에 의한 주구조부재의 영향에 대한 내용을 다루었다. 자중으로 인해 초지 수직변위를 갖는 52층 철근콘크리트 구조물에 지진하중을 적용하여 구조물에 미치는 영향을 평가하였다. 각 수직구조요소에 대한 축소량은 전산화된 기둥축소 해석 프로그램을 이용하여 예측되었으며 지진하중으로 인한 축소량이 보정된 구조물과 보정되지 않은 구조물 사이의 응력을 조사하였다.

• 한국식품영양과학회지
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• 제29권2호
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• pp.231-234
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• 2000

시판 탕수육을 대두유와 shortening으로 연속적으로 사용하여 튀긴 후 탕수육의 이화학적 및 관능적 변화와 튀김유의 이화학적 변화를 측정하여 이를 통한 한계 사용 횟수를 예측하고자 하였다. 튀김유의 TBA값은 대두유가 shortening보다 사용횟수에 따른 증가가 뚜렷하였으나, 탕수육의 경우에는 반대로 shortening을 사용한 탕수육이 대두유로 튀긴 탕수육보다 증가율이 높게 나타났다. 튀김횟수 증가에 따른 튀김유의 산가와 과산화물가는 증가하였으며 shortening에서 과산화물가의 변화가 크게 나타났다. 대두유로 튀긴 탕수육의 TBA값과 가장 상관 관계가 높은 풍미를 선정하여 한계사용횟수를 구한 결과 약 9회로 나타났고, shortening으로 튀긴 탕수육의 TEA 값과 가장 상관관계가 높은 인자인 조직감을 선정하여 한계 사용횟수를 측정한 결과 약8회로 나타났다. 대우유와 shortening의 한계사용횟수를 예측하기 위해 식품공전에 규정된 산가를 회귀방정식에 대입한 결과 두 기름 모두 약 8회로 나타나 위의 결과와 비슷한 한계사용횟수를 나타났다.

• Advances in concrete construction
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• 제5권2호
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• pp.155-171
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• 2017

The phenomenon of concrete column shortening has been widely acknowledged since it first became apparent in the 1960s. Axial column shortening is due to the combined effect of elastic and inelastic deformations, shrinkage and creep. This study aims to investigate the effects of ambient temperature, relative humidity, cement hardening speed and aggregate type on concrete column shortening. The investigation was conducted using a column shortening prediction model which is underpinned by the Eurocode 2. Critical analysis and evaluation of the results showed that the concrete aggregate types used in the concrete have significant impact on column shortening. Generally, aggregates with higher moduli of elasticity hold the best results in terms of shortening. Cement type used is another significant factor, as using slow hardening cement gives better results compared to rapid hardening cement. This study also showed that environmental factors, namely, ambient temperature and relative humidity have less impact on column shortening.

• 한국건축시공학회지
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• 제5권4호
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• pp.145-152
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• 2005

Long-term axial shortening of the vertical elements of tail buildings results in differential movements between two elements and may lead to the additional moments of connection beam and slab elements, and other secondary effects, such as cracks of partitions or curtain walls. Accurate prediction of time-dependent column shortening is essential for tall buildings from both strength and serviceability aspects. The compensation method is different from reinforced concrete and SRC(Steel Reinforced Concrete) members. The SRC columns are usually compensated according to total differential shortening between two vertical elements. In this study, column shortenings of 37-story W building under construction are predicted and compensated. The SRC column shortenings are compared with the actual column shortening by field measurement and the column shortenings are reanalysed and recompensated.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2006년도 정기 학술대회 논문집
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• pp.175-181
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• 2006

The prediction of time-dependent column shortening is essential for tall buildings considering both strength and serviceability aspects. The Column shortening of tall buildings with transfer floor should be calculated considering the long-term deflection of transfer girder. In this study, both the column shortening and the deflection of transfer girder of 45-story tall concrete building are predicted. The column shortening considering deflection of transfer girder are compared with the actual column shortening by field measurement.

• 국제초고층학회논문집
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• 제6권1호
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• pp.73-82
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• 2017

Vertical shortening in tall buildings would be of little concern if all vertical elements shortened evenly. However, vertical elements such as walls and columns may shorten different amounts due to different service axial stress levels. With height, the differential shortening may become significant and impact the strength design and serviceability of the building. Sometimes column transfers or other vertical structural irregularities may cause differential shortening. If differential shortening is not addressed properly, it can impact the serviceability of the building. This paper takes the perspective of a structural engineer in planning the design, predicting the shortening and its effects, and communicating the information to the contractor.