The effect of panel zone (PZ) flexibility and yielding on the stiffness and strength of steel moment resisting frames (SMRF) has been the topic of numerous papers over the past thirty years. When properly detailed, the PZ is an excellent source of energy dissipation, even under large inelastic deformations. Due to these large inelastic deformations, the PZ region may also be a weak link in steel moment frame behavior. Because of the importance of PZ deformation in the behavior of steel frames, accurate modeling of this region is critical. Two of the most commonly used mathematical models for representing PZ behavior are investigated. They are referred to herein as the Krawinkler model and the Scissors model. From the literature review conducted at the beginning of this study, it was determined that there were no PZ models available that accounted for the elastic drift associated with PZ flexure which could be used in computer representations using commercial software that is currently available. This thesis details the analytical work used to establish the estimated elastic drift associated with PZ flexure and a method to include this estimated drift and the contribution of continuity plates in the Krawinkler and Scissors models. This study is initially focused on elastic deformations of individual structural subassemblages. First, formulas are derived to account for each major elastic component of drift in an individual subassemblage. The results from these derivations were implemented into a computer program named PANELS to allow for rapid calculation of the estimated drifts. Then, the properties (elastic and inelastic) for the Krawinkler and Scissors models are derived in their entirety. The Krawinkler model's results are compared to the results from PANELS, neglecting the PZ flexural component in PANELS and any inelastic contributions in the Krawinkler model. Since the Krawinkler model does not include PZ flexure, this established that the derived formulas accounted for all the remaining sources of elastic strain energy, assuming that the Krawinkler model is accurate. The results from PANELS are compared to those from finite element models developed using ABAQUS. Using the ABAQUS results, a method for determining the elastic drift associated with PZ flexure in PANELS is presented. A detailed inelastic study of the Krawinkler and Scissors models is then conducted both on the subassemblage level and on full structural frames to determine any differences associated with them. First, the two models are compared to each other on a subassemblage level to ensure that they both give the same results. Then, both PZ models are included in multiple full structural frames using various design configurations and loading conditions to ascertain their differences. Initially it was believed that there would be a large disparity between the two models. This study shows that there is actually little difference between the two models, although the kinematics of the Scissors model is still questionable. Elastic and inelastic comparisons between the PANELS formulas (elastic) and the ABAQUS models (elastic and inelastic) and data collected from tests performed at Lehigh University by Dr. James Ricles are then presented. This was done to show that the ABAQUS models and the PANELS formulas (including the PZ flexural component) give an accurate estimation of the drift of a subassemblage. The results from these comparisons show that the modeling techniques used are accurate and not including PZ flexural component of drift will cause the overall drift estimate to be unconservative. Finally, a method of including the elastic component of drift attributed to PZ flexure and continuity plates in both models is presented. The Ricles' Lehigh test data is again used in an inelastic comparison between the original Krawinkler and Scissors models and their updated counterparts. These comparisons show that including this component enables both the Krawinkler and Scissors models to more accurately estimate the total drift of an individual subassemblage. / Master of Science

A continuous load path in a structure is always the best way to transmit the load from the upper story to the foundation. However, there is a tradition of using irregular shapes of structures nowadays to enhance the aesthetic, make a terrace, or for getting sunlight. This irregular shape disrupts the continuous load path of the structure and there is the formation of a high-stress zone in the structure which may lead to failure in case of extreme events. During the event of an earthquake, a structure that has an irregularity in its mass, stiffness, and strength suffers more damage as compared to its regular counterpart. So, we need to pay more attention while designing the irregular structure so that it can withstand the force acting on it and ensure the safety of people. So, in this thesis, the seismic response of structures with vertical irregularity is studied. For this purpose, the fundamental time periods of the structures with vertical irregularity are studied and compared with their regular structure. The obtained result is compared with the approximate fundamental period, Ta, given by ASCE/SEI 7-16. Also, the location of critical columns which has the highest load ratio is studied and designed.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19299号 / 工博第4096号 / 新制||工||1631(附属図書館) / 32301 / 京都大学大学院工学研究科建築学専攻 / (主査)教授 中島 正愛, 教授 川瀬 博, 教授 竹脇 出 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20697号 / 工博第4394号 / 新制||工||1683(附属図書館) / 京都大学大学院工学研究科建築学専攻 / (主査)教授 池田 芳樹, 教授 西山 峰広, 准教授 聲高 裕治 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

Maximum interstory drift and the distribution of this drift along the height of the structure are the main causes of structural and nonstructural damage in frame type buildings subjected to earthquake ground motions. Estimation of maximum interstory drift ratio is a good measure of the local response of buildings. Recent earthquakes have revealed the susceptibility of the existing building stock to near-fault ground motions characterized by a large, long-duration velocity pulse. In order to find rational solutions for the destructive effects of near fault ground motions, it is necessary to determine drift demands of buildings. Practical, applicable and accurate methods that define the system behavior by means of some key parameters are needed to assess the building performances quickly instead of detailed modeling and calculations. In this study, simple equations are proposed in order for the determination of the elastic interstory drift demand produced by near fault ground motions on regular and irregular steel frame structures. The proposed equations enable the prediction of maximum elastic ground story drift ratio of shear frames and the maximum elastic ground story drift ratio and maximum elastic interstory drift ratio of steel moment resisting frames. In addition, the effects of beam to column stiffness ratio, soft story factor, stiffness distribution coefficient, beam-to-column capacity ratio, seismic force reduction factor, ratio of pulse period to fundamental period, regular story height and number of stories on elastic and inelastic interstory drift demands are investigated in detail. An equation for the ratio of maximum inelastic interstory drift ratio to maximum elastic interstory drift ratio developed for a representative case is also presented.