DOI QR코드

DOI QR Code

Stress-transfer in concrete encased and filled tube square columns employed in top-down construction

  • Kim, Sun-Hee (Department of Architectural Engineering, University of Seoul) ;
  • Yom, Kyong-Soo (Harmony Engineering) ;
  • Choi, Sung-Mo (Department of Architectural Engineering, University of Seoul)
  • Received : 2016.06.09
  • Accepted : 2016.09.11
  • Published : 2016.09.20

Abstract

Top-down construction is a construction technique in which pit excavation and structure construction are conducted simultaneously. Reducing construction time and minimizing noise and vibration which affect neighboring structures, the technique is widely employed in constructing downtown structures. While H-steel columns have been commonly used as core columns, concrete filled steel tube (CFT) columns are at the center of attention because the latter have less axial directionality and greater cross-sectional efficiency than the former. When compared with circular CFT columns, square CFT columns are more easily connected to the floor structure and the area of percussion rotary drilling (PRD) is smaller. For this reason, square CFT columns are used as core columns of concrete encased and filled square (CET) columns in underground floors. However, studies on the structural behavior and concrete stress transfer of CET columns have not been conducted. Since concrete is cast according to construction sequence, checking the stress of concrete inside the core columns and the stress of covering concrete is essential. This paper presents the results of structural tests and analyses conducted to evaluate the usability and safety of CET columns in top-down construction where CFT columns are used as core columns. Parameters in the tests are loading condition, concrete strength and covering depth. The compressive load capacity and failure behavior of specimens are evaluated. In addition, 2 cases of field application of CET columns in underground floors are analyzed.

Keywords

References

  1. AISC (2005, 2010), Steel Construction Manual; American Institute of Steel Construction Ins.
  2. Fenollosa, E., Gil, E., Cabrera, I. and Vercher, J. (2015), "Elastic-plastic formulation for concrete encased sections interaction diagram tracing", Steel Compos. Struct., Int. J., 19(4), 861-876. https://doi.org/10.12989/scs.2015.19.4.861
  3. KBC (2005, 2009), Korean Building Code; Architectural Institute of Korea.
  4. Kim, B.H., Sim, H.J., Choi, B.J. and Lee, E.T. (2011), "Flexural behavior of concrete filled seismic resistant steel tubular columns subjected to axial and cyclic lateral load", J. Korean Soc. Steel Construct., 23(3), 317-326. [In Korean]
  5. Kim, S.H., Yom, K.S. and Choi, S.M. (2013), "Evaluation of the fire resistance performance of interior anchor type CFT columns through loaded heating test", Int. J. High-Rice Build., 2(1), 39-48.
  6. Kim, S.H., Yom, K.S. and Choi, S.M. (2014), "Improving fire performance with steel-fibers for internally anchored square composite columns", J. Construct. Steel Res., 103, 264-274. https://doi.org/10.1016/j.jcsr.2014.09.003
  7. Kim, S.H., Yom, K.S. and Choi, S.M. (2015), "A study on the structural performance of new shape built-up square column under concentric axial load", Steel Compos. Struct., Int. J., 18(6), 370-377.
  8. Ky, V.S., Tangaramvong, S. and Thepchatri, T. (2015), "Inelastic analysis for the post-collapse behavior of concrete encased steel composite columns under axial compression", Steel Compos. Struct., Int. J., 19(5), 1237-1258. https://doi.org/10.12989/scs.2015.19.5.1237
  9. Lee, C.H., Kang, K.Y., Kim, S.Y. and Koo, C.H. (2013), "Review of structural design provisions of rectangular concrete filled tubular columns", J. Korean Soc. Steel Construct., 25(4), 389-398. [In Korean] https://doi.org/10.7781/kjoss.2013.25.4.389
  10. Li, N., Lu, Y.Y., Li, S. and Liang, H.J. (2015), "Statistical-based evaluation of design codes for circular concrete-filled steel tube columns", Steel Compos. Struct., Int. J., 18(2), 519-546. https://doi.org/10.12989/scs.2015.18.2.519
  11. Park, G.D. (2011), "Strength evaluations and behavior properties considering confined effects for steel composite circular columns", Doctorate Thesis; Inha University, Korea.
  12. Seon, W.H. (2010), "Experimental study of strength and deformation behavior for CET column", M.S. Dissertation, Inha University, Korea.
  13. Tsuda, K. and Matsui, C. (1987), "Structural performance and limiting width thickness ratio of concrete filled steel square tubular columns", Earthquake Engineering, New Zealand, August, pp. 25-36.
  14. Xu, T., Xiang, T., Zhao, R. and Zhan, Y. (2010), "Nonlinear finite element analysis of circular concretefilled steel tube structures", Struct. Eng. Mech., Int. J., 35(3), 315-333. https://doi.org/10.12989/sem.2010.35.3.315
  15. Zaharia, R. and Dubina, D. (2014), "Fire design of concrete encased columns: Validation of an advanced calculation model", Steel Compos. Struct., Int. J., 17(6), 835-850. https://doi.org/10.12989/scs.2014.17.6.835

Cited by

  1. Experimental study on seismic behavior of joints connecting precast H-steel reinforced concrete beams and concrete-filled steel tube columns vol.45, pp.None, 2022, https://doi.org/10.1016/j.jobe.2021.103444