Torsion-coupling effect

Specimens Of each material three prismatic specimens of rectangular cross-section were cut from plates of 9 mm nominal thickness. In order to avoid difficulties arising from torsional coupling effects connected with off-axis flexure, only on-axis specimens were prepared, i.e. the geometrical axes of each specimen coincided with the principal axes of the respective material (Fig.l). The nominal cross-section of the six specimens was 9 X 18.3 mm, the length varied between 200 mm and 265 mm. 

Torsional flexing and related torsion-vibration-coupling effects... 

Helfand and coworkers analyzed BD simulations of polyethylene in terms of cooperative transition pairs [39]. They found that, after a conformational transition occurred in polyethylene, a second transition occurred nearby along the chain within a very short time (3 ps at 425 K) in 29% of cases. The second transition always occurred about the second-neighbor torsion, relative to the initial transition. This second-neighbor coupling effect had been predicted previously by Helfand [85]. Almost all of the cooperative transitions were the motions shown in Fig. 7b, c. 71% of all the transitions occurred without a closely following transition. We will refer to these as "isolated transitions. ... 

Kan, C.L. Chopra, A.K. 1977. Effect of torsional coupling on earthquake forces in buildings. Journal of Structural Division ASCE 103(4) 805-819. 

Torsionally Coupled (TC) Effect An effect that describes the coupling of translation and torsion of a building due to the inconsistency of the center of rigidity and the center of mass. 

Yoshida O (2003) Torsionally coupled response control of earthquake excited asymmetric buildings development and application of effective control systems using smart dampers. PhD thesis, Washington University, Sever Institute of Technology, Depardnent of Civil Engineering (supervised Dyke SJ)... 

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