Effects of plan irregularities on seismic response of tall buildings | |
| Author | Thu Rein Htun |
| Call Number | AIT Thesis no.ST-23-09 |
| Subject(s) | Earthquake hazard analysis Tall buildings--Earthquake effects Structural analysis (Engineering) |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Structural Engineering |
| Publisher | Asian Institute of Technology |
| Abstract | Tall buildings with irregularities have uncommon responses from seismic events compared to normal ones. For structural irregularities, there are normally two types such as horizontal irregularities and vertical irregularities. Mostly, tall buildings with both horizontal and vertical irregularities are analyzed and studied in order to know the seismic behavior. This will not capture the effects of the specific irregularities type. Therefore, studying the effects of the specific irregularities of tall buildings under seismic response is important. In this study, a preliminary analysis of 200 tall buildings is first conducted to determine the most common plan irregularities in Thailand. Two real tall buildings (a 49-story building and a 39-story building) with the most common plan irregularities (Torsional Irregularity and Reentrant Corner Irregularity) are selected with the help of AIT Solutions. These two buildings are then modified to carry out the comparison between regular and irregular models. Furthermore, those buildings conducted Linear Time History Analysis, Response Spectrum Analysis, and Modal Response Spectrum Analysis. Carrying out various kinds of analysis procedures can show the accuracy of the analysis. For all the analysis, ETABS-V20 is used. Furthermore, the response spectra were already created according to ASCE-7-16 and provided from the selected buildings’ information. Thus, a pair of ground motions (X and Y) is chosen to match the response spectra to carry out the seismic analysis by using SeismoMatch. From the analysis, bi-directional or 3-directional mode shapes have occurred in irregular buildings. Irregular buildings have irregular centers of rigidity compared to regular buildings. Both the linear time history analysis and response spectrum results are close to each other which means that the analysis is accurate. In a Torsional Irregular Building, in a group of the same elements, elements that are the furthest from the center of rigidity have higher demand than elements that are the closest to the center of rigidity. In a Reentrant corner irregular building, an element that is at or closest to the reentrant corner has the highest demand. Sometimes, the critical demands in both irregular buildings can be higher than in regular buildings. |
| Year | 2023 |
| Type | Thesis |
| School | School of Engineering and Technology |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Pennung Warnitchai, |
| Examination Committee(s) | Anwar, Naveed;Krishna, Chaitanya |
| Scholarship Donor(s) | AIT Alumni’88 Scholarship |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2023 |