Structural design method of the steel brush type loading platen adopted in multi-axial compression experiments

Myung Sagong; Jun S. Lee; Sung-soo Kim

doi:None

All Issue

2007 Vol.9, Issue 4 Preview Page Next Page

Structural design method of the steel brush type loading platen adopted in multi-axial compression experiments 다축압축 실험에 적용되는 철제 빗살구조 재하판의 구조 설계 기법

31 December 2007. pp. 351-359

PDF XML

Abstract

Multi-axial compression tests have been frequently conducted to evaluate the in situ properties of rock masses and the mechanical behaviors of rock strata through the model tests. Without the proper boundary condition for the model tests, the mechanical behavior of rock mass would deviate, as can be expected, from the in situ conditions. The boundary condition will affect the internal stress distribution of the specimens and cause some distortion on the measurement. In this study, a design process regarding the steel brush, which has been employed for multi-axial compression test to reduce the frictional restraint along the specimen/loading platen interface, is introduced. The individual brushes are regarded as a simple column and beam to calculate the cross-sectional size and length of the brushes in consideration of the buckling capacity and the allowable deflection.

Keywords

Multi-axial compression test

Steel brush loading platen

Boundary conditions

Steel brush design

Buckling

Deflection

지반재료중의 하나인 암반의 물성평가 및 원지반상에서의 역학적 암반거동 평가를 위하여 다축(이축 혹은 진삼축) 압축실험이 수행되고 있다. 이러한 다축압축 실험의 경우에는 적용되는 경계조건에 따라 실험체내의 내부 응력이 예상과 다르게 작용하게 되며 결국 실험결과의 왜곡을 발생시킬 수 있으므로 적절한 경계조건의 설정은 필수적이다. 본 연구에서는 기존에 하중재하판과 실험체의 경계면상에서 발생할 수 있는 마찰저항을 감소시키기 위하여 사용된 철제 빗살구조의 재하판에 대한 구조 설계 방법을 제안하고자 한다. 각 빗살의 길이 및 단면의 계산을 위하여 각 빗살은 고정단에 지지된 단순보와 고정단에 지지된 기둥의 형태로 가정되었으며 좌굴과 실험체의 변형에 따른 빗살의 처짐을 고려하는 방법이 적용되었다.

키워드

다축압축실험

철제 빗살재하판

경계조건

철제 빗살 설계

좌굴

처짐

References

1.Bobet, A. (2001), “Influence of the loading apparatus on the stresses within biaxial specimens”, American Society for Testing and Materials, Vol. 24. No. 3, pp. 256-272.

2.Brown E.T., Gonano, L.P. (1974), “Improved compressiontest technique for soft rock”, Journal of the Geotechnical Engineering Division, Vol. 100, No. GT2, pp. 196-199.

3.Gerstle, K. H., Linse, D. L., Bertacchi, P., Kotosovos, M. D., Ko, H., Newman, J. B., Rossi, P., Schikert, G., Taylor, M. A., Traina, L. A., Zimmerman, R. M., Bellotti, R. (1976), “Strength of concrete under multiaxial stress state”, Douglass McHenry International Symposium of Concrete and Concrete Structures, pp. 103-131.

4.Hilsdorf, H. K. (1965), “Die Bestimmung der ziveiachsigen Festigkeit von Benton” (The experimental determination of the biaxial strength of concrete), Proceedings, Deutscher Ausschuss fur Stahlbeton, Berlin, Germany, Vol, 173.

5.Jaeger, J. C., Cook, N. G. (1979), “Fundamentals of rock mechanics”, Third Edition, Chapman and Hall.

6.Lee, S. K., Song, Y. C., Han, S. H. (2004), “Biaxial behavior of plain concrete of nuclear Containment building”, Nuclear Engineering and Design, Vol. 227, pp. 143-153.

7.Vonk, R. A. (1992), “Softening of concrete loaded in com-pression”, Ph.D. Thesis, Eindhoven University of Technology.

Information

Publisher :Korean Tunneling and Underground Space Association
Publisher(Ko) :한국터널지하공간학회
Journal Title :Journal of Korean Tunnelling and Underground Space Association
Journal Title(Ko) :한국터널지하공간학회 논문집
Volume : 9
No :4
Pages :351-359

Journal of Korean Tunnelling and Underground Space Association ISSN:2233-8292(Print) 2287-4747(Online) 한국터널지하공간학회 논문집

All Issue