Background: Height is an important factor in determining a person’s appearance, so people often wear height increase elevator shoes insoles (HIESI) or high heels to make themselves look taller. However, high heels often act as a risk factor for musculoskeletal diseases. Objectives: To investigated how muscle tone and muscle stiffness in the lumbar region of young adult men varied according to the height of the HIESI, and analyzed the correlation. Design: Non-randomised trial. Methods: Muscle tone and muscle stiffness in the upper and lower lumbar regions of 20 healthy young adult men in an upright standing position were measured as the subjects wore no insoles and 2 cm, 3 cm, and 4 cm insoles. Results: Muscle tone and muscle stiffness in the lumbar region did not show a significant change according to the increased height of the HIESI. However, a positive correlation was observed when the subjects wore 4 cm HIESI, as there was a significant increase (P<.05) in muscle tone and stiffness in the left side of the upper lumbar region and in the right side of the lower lumbar region. Conclusion: Wearing HIESI for short periods of time in the static standing position did not cause a change in muscle tone and muscle stiffness in the lumbar region. However, wearing 4 cm HIESI demonstrated a correlation of increased muscle tone and stiffness in the upper and lower lumbar regions in an asymmetric manner.

PURPOSES : In this study, high-viscosity grout for increasing ground stiffness is developed using industrial byproducts. METHODS : Based on literature review, the viscosity and viscosity expression time of domestic and foreign anti-washout admixture underwater were evaluated. In addition, grout was prepared by mixing 5% to 40% of fly ash (FA) in a standard mixture. Flow, setting time, and compressive strength tests were conducted to evaluate the quality of the grout. RESULTS : Experimental results show that the viscosity required is 35,000 to 40,000 cps, whereas the viscosity expression time required exceeds 300 min. As the amount of FA used for grouting increases, the physical and mechanical performances deteriorate. The strength of a test specimen manufactured underwater is lower than that of a test specimen manufactured under air, and the decrease on day 28 is lower than that on day 3. The FA applied to the grout should be less than 20%. CONCLUSIONS : Although industrial byproducts, which exhibit high viscosity, offer excellent mechanical performance and are thus suitable as a solidifying agent for strengthening grout, their application in the field must be evaluated.

본 연구의 목적은 초고층건물의 횡강성 증가요인 효과를 분석하고 이를 바탕으로 초기 구조설계에서 활용할 수 있는 횡강성 증가율 예측값을 제시하는 것이다. 이를 위해서 먼저 Box형과 T형의 전형적인 평면을 갖는 60층의 초고층건물 기본모델을 생성하였다. 그리고 초고층건물의 횡강성 증가요인으로서 아웃리거의 추가, 재료강도의 증가, 코어 벽체 단면크기의 증가, 아웃리거 연결기둥 및 아웃리거 벽체의 단면크기 증가를 선정하였다. 다음에는 이 요인들을 기본모델에 적용하여 구조해석을 수행하고, 그 결과로부터 각 요인이 횡강성 증가에 미치는 영향과 상호관계 등을 분석하였다. 마지막으로, 이 분석결과를 바탕으로 초고층건물의 초기 구조설계를 위한 횡강성 증가요인별 강성증가율 예측값을 제안하였으며, 예제 초고층건물에 적용하여 그 타당성을 검토하였다.