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Mechanical Properties of a Cylindrical Pipe Inside a Statically Indeterminate Structure
New Physics: Sae Mulli 2017; 67: 1145~1150
Published online September 29, 2017;
© 2017 New Physics: Sae Mulli.

Jong-Ho PARK*

Department of Science Education, Chinju National University of Education, Jinju 52673, Korea 
Correspondence to:
Received July 13, 2017; Revised August 1, 2017; Accepted August 6, 2017.
cc This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
In order to improve the rigidity of the cylindrical pipe inside a statically indeterminate structure (triangular, square, pentagonal, and hexagonal structure), we modified the cylindrical pipe to investigate its mechanical properties. We measured the rigidity of the cylindrical pipe by using the elasticity of the stress - strain diagram according to statically indeterminate structure. We confirmed that the elastic modulus was increased 45.696 N/cm$^2$, 66.478 N/cm$^2$, 90.912 N/cm$^2$, and 111.55 N/cm$^2$ for the internal triangular, square, pentagon, and hexagonal structures, respectively. As a result of analyzing the axial force of the pipe structure by using the equilibrium equation of force and moment, in the case when the pipe structure had many contacts between the cylindrical pipe and the inner irregular structure, the member of the irregular structure mainly received the axial force, which was confirmed to be consistent with the increase in the elastic modulus.
PACS numbers: 46.25.-y, 45.80.+r, 89.20.-a, 89.20.Bb, 46.70.De
Keywords: Mechanics, Rigidity, Statically indeterminate structure, Stress, Strain

September 2017, 67 (9)