| Author | Ahmed, Hafiz Faheem |
| Call Number | AIT Thesis no.ST-18-22 |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Structural Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. ST-18-22 |
| Abstract | Podiums are bigger floor area at the lower stories of a tall building. Now a days above grade podium levels are common in multi-use tall buildings especially for hotel ball rooms, lobby spaces, public spaces, meeting rooms, retail spaces or parking area etc. Floor and roof slabs are key components in podium and act as diaphragms. Diaphragms are the major components of a seismic load resisting system in a building, responsible for stabilizing the building by tying the vertical elements together and transferring the lateral forces (transfer forces and inertial forces) from one element of seismic load resisting system to another element. Current code guidelines are based on the Equivalent Lateral Force (ELF) procedure which considers both transfer forces (acting inplane to the floor due to the dynamics of floors above the floor under consideration) and inertial forces (acting in-plane of the floor itself). Both the actions are not properly described by the ELF procedure as the higher mode effects are not considered by this method, which resultantly affect the diaphragm inertial forces as the structure enter the nonlinear range. For the evaluation of effects of nonlinear response of diaphragm on design of podium in tall buildings, a case study building was selected and was modified in such a way that there should be sufficient area of the podium diaphragm as compared to the area of tower. The diaphragm was designed according to code provisions. Three different models of the building were created; (1) Building linear and the diaphragm also linear, (2) Building nonlinear but the diaphragm linear and (3) Building nonlinear and the diaphragm also nonlinear. For the third model, the diaphragm was modeled as layered shell element (LSE). First model was analyzed using linear time history analysis (LTHA) and second and third models were analyzed using Nonlinear time history analysis (NLTHA). Global response of the three models were compared and local response of diaphragm for the three models and code based was compared. It was found that there is no significant difference between the linear diaphragm and nonlinear diaphragm on response of the building. |
| Year | 2018 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ST-18-22 |
| 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) | Punchet Thammarak;Anwar, Naveed; |
| Examination Committee(s) | Pennung Warnitchai;Thanakorn Pheeraphan; |
| Scholarship Donor(s) | AIT Fellowship; |
| Degree | Thesis (M.Eng.) - Asian Institute of Technology, 2018 |