| Author | Thanathip Wongsorod |
| Call Number | AIT Thesis no.ST-20-22 |
| Subject(s) | Precast concrete beams--Testing
|
| 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-20-22 |
| Abstract | Nowadays, precast concrete has been used widely due to shortage of labor in site construction, controllable quality of a concrete member, so precast concrete has been improved widely. However, the lack of using precast concrete is connection between precast members, so in this thesis presents beams-column sub-assemblages using u-shell and grouted tube rebar splices. For the u-shells which are attached at the end of the beams, it is a technique that has been developed for many previous students to make sure that can carry self-weight of those beams. One specimen was tested under cyclic loading following ACI3741_05 (Reapproved 2019). For test results can be summarized that this specimen was not satisfied strong column-weak beam concept due to all longitudinal bars in column were yield and first yield was founded at 1.75% drift at bottom part of the column while there was no yield at beams’ rebars. Shear failure did not occur due to all strain gauges in shear rebars were not yield. Unfortunately, the test can go to only 2.75% because there was a failure occurred on foundation, so the test had to stop, after testing cracks were observed and founded that bottom column was the weakness one due to concrete spalled out and has the highest strain in longitudinal bars. For all hysteretic loops were the same that loads at the pulled directions were higher than pushed direction due to unsymmetrical structure (rebars covering). In the beginning of the drifts, all slopes were good that represent good stiffness in the elastic range. However, the slopes had degradation in the higher story drift levels. At the higher levels of story drifts area enclosed the curves were higher due to more damage happened which causes low stiffness at the beginning of the loops. For load at the last loop of 2.75% story drift has dropped rapidly due to failure at the foundation. For secant stiffnesses of this specimen were 3.335 KN/mm in the right direction (Pushed direction) and 4.61 KN/mm in the left direction (Pulled direction) when it is compared to ACI 3741_05(Reapproved 2019), the sitffnesses were satisfied. For other behaviors are presented in this thesis at chapter 4 such as Envelop cure which represents maximum load of each story drift, Energy dissipation. For rotation, there was some error in two displacement transducers located on both bottom left beam and bottom right beam which were LVDT5 and LVDT7 because of concrete spalling at bottom column which cause the unpleasant patterns of the rotation curves””. |
| Year | 2020 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. ST-20-22 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| 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,; |
| Examination Committee(s) | Pennung Warnitchai;Thanakorn Pheeraphan,; |
| Scholarship Donor(s) | Royal Thai Government Fellowship; |
| Degree | Thesis (M. Eng.) - Asian Institute of Technology, 2020 |