| Author | Tsai, Ying-chau |
| Call Number | AIT Thesis no. 694 |
| Subject(s) | Wind-pressure
Structural dynamics
|
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering of the Asian Institute of Technology,
Bangkok, Thailand. |
| Publisher | Asian Institute of Technology |
| Abstract | The response of a tall multi-flue stack to wind loads was investigated in this study. Each flue consists of a number of equal lengths supported on bearings. The outer shell mass was idealized into the same number of elements as the flue lengths. The sys tern\' was therefore represented by a number of masses with associated spring and damping
elements. The equation of motion was derived by means of Lagrange equation incorporating the rotational effects of all masses. The stiffness of the outer shell was computed on the assumption that it behaves as a
slender cantilever beam. The damping coefficients in the system was assumed to be proportional to masses and stiffness\'s Two types of wind loads, gust and vortex actions> were considered. The gust load was computed from a simulated hurricane velocity. The critical wind velocity for. vortex action was calculated from the · fundamental frequency ·Of the system. Expressing the displacements of each mass in term of modal displacements, the governing equations of the letters become uncoupled, and
their solutions for gust load was obtained by means of a numerical integration. For vortex load the steady state solution is the most relevant for practical purposes. The stack chosen for illustrating the analysis is 242 m high and made of reinforced concrete. The outer shell with a 26m diameter encloses and supports three elliptical reinforced concrete flues. It is
found that a dynamic analysis for the response of the structure subjected to wind loads is very important and the vortex action is most critical in the analysis.
The response of this type of structures depends very much upon damping and wind load coefficients. More investigations on these coefficients both by means of a model and a prototype are recommended. |
| Year | 1974 |
| Type | Thesis |
| School | Student Research Before 1980 |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Thesis (Year <=1979) |
| Chairperson(s) | Karasudhi, Pisidhi |
| Scholarship Donor(s) | Government of Republic of China |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 1974 |
