In this article, a performance assessment of the evacuation system is established for educational buildings. Structural and geotechnical information of the building is collected and introduced into a database. A similar procedure was realized for the information related to the occupants. Using this information, a) the structural fragility and localized collapse were determined and b) the interaction of the person with the partial collapse was established. For the first aspect, nonlinear time history was used, and for the second, the agent-based modeling was applied to recreate the reaction of people that face the micro collapse. Therefore, the important results of this evaluation are: 1) To localize collapsed beans and columns that make inoperable evacuation routes, 2) to localize bottleneck areas that people concentration during evacuation, and 3) quantification of affected people, in terms of persons caught up in the building that cannot evacuate.

The steel bridge system referred to as Simple for Dead load and Continuous for Live load (SDCL) has gained popularity in non-seismic areas of the country. Accordingly, it results in many advantages including enhanced service life and lower inspection and maintenance costs as compared to conventional steel systems. To-date, no research studies have been carried out to evaluate the behavior of the SDCL steel bridge system in seismic areas. The main objective of this research was to extend the application of SDCL to seismic areas. The concept of the SDCL system was developed at the University of Nebraska-Lincoln and a complete summary of the research is provided in five AISC Engineering Journal papers. The SDCL system is providing steel bridges with new horizons and opportunities for developing economical bridge systems, especially in cases for which accelerating the construction process is a priority. The SDCL steel bridge system also provides an attractive alternative for use in seismic areas. The SDCL concept for seismic areas needed a suitable connection between the girder and pier. In this research, an integral SDCL bridge system was considered for further investigation. The structural behavior and force resistance mechanism of the proposed seismic detail considered through analytical study. The proposed connection evaluated under push-up, push-down, inverse and axial loading to find the sequence of failure modes. The global and local behavior of the system under push-down forces was mainly similar to non-seismic detail. The nonlinear time history analysis indicated that there is a high probability that bottom flange sustains tension forces under seismic events. The finite element model subjected to push-up forces to simulate the response of the system under the vertical component of seismic loads. However, the demand-capacity ratio was low for vertical excitation of seismic loads. Besides finite element results showed that continuity of bottom flange increased ductility and capacity of the system. While the bottom flange was not continuous, tie bars helped the system to increase the ultimate moment capacity. To model the longitudinal effect of earthquake loads, the model subjected under inverse forces as well as axial forces at one end. In this case scenario, dowel bars were most critical elements of the system. Several finite element analyses performed to investigate the role of each component of preliminary and revised detail. All the results demonstrated that continuity of the bottom flange, bolts area (in the preliminary detail), tie bars over the bottom flange (in the revised detail) were not able to provide more moment capacity for the system. The only component increased the moment capacity was dowel bars. In fact, increasing the volume ratio of dowel bars could be able to increase the moment capacity and prevent premature failure of the system. This project was Phase I of an envisioned effort that culminated in the development of a set of details and associated design provisions to develop a version of the SDCL steel bridge system, suitable for the seismic application. Phase II of this project is an ongoing project and currently the component specimen design and test setup are under consideration. The test specimen is going to be constructed and tested in the structures lab of Florida International University. A cyclic loading will be applied to the specimen to investigate the possible damages and load resistance mechanism. These results will be compared with the analysis results. In the next step, as phase III, a complete bridge with all the components will be constructed in the structures lab at the University of Nevada-Reno. The connection between steel girders will be an SDCL connection and the bridge will be subjected to a shake table test to study the real performance of the connection due to earthquake excitation.

A typical 1960s Type 2 Construction steel MRF hospital structure in Quebec, representative of a prevalent construction philosophy of the time, was investigated and modelled in OpenSees using an advanced strength degradation model. The structure was then subjected to a nonlinear time-history analysis (NLTHA) for Montreal (MTL) and Vancouver (VAN) ground motions and was found to be deficient under the design hazard levels. Retrofits were proposed for the two orthogonal frames at both sites using a performance-based approach. An experimental program determined that the connections had less ductility than expected and began deteriorating around 2.0% interstorey drift. The OpenSees model was updated according to the experimental connection behaviour and the predicted NLTHA performance of the structure worsened. The proposed retrofit designs for both orthogonal frames in both MTL and VAN were updated with the new connection behaviour and final retrofit designs were proposed.

A typical 1960s Type 2 Construction steel MRF hospital structure in Quebec, representative of a prevalent construction philosophy of the time, was investigated and modelled in OpenSees using an advanced strength degradation model. The structure was then subjected to a nonlinear time-history analysis (NLTHA) for Montreal (MTL) and Vancouver (VAN) ground motions and was found to be deficient under the design hazard levels. Retrofits were proposed for the two orthogonal frames at both sites using a performance-based approach. An experimental program determined that the connections had less ductility than expected and began deteriorating around 2.0% interstorey drift. The OpenSees model was updated according to the experimental connection behaviour and the predicted NLTHA performance of the structure worsened. The proposed retrofit designs for both orthogonal frames in both MTL and VAN were updated with the new connection behaviour and final retrofit designs were proposed.

An analytical study is performed to evaluate the influence of shear wall area to floor area ratio on the behavior of existing mid-rise reinforced concrete buildings under earthquake loading. The seismic performance of five existing school buildings with shear wall ratios between 0.00% and 2.50% in both longitudinal and transverse directions and their strengthened counterparts are evaluated. Based on the structural properties of the existing buildings, additional buildings with varying shear wall ratios are designed. Consequently, twenty four buildings with different floor plans, number of stories, cross-sectional properties of the members and material strengths are acquired. Nonlinear time-history analyses are performed for all buildings by utilizing the software program, SAP2000 v14.2.0. under seven different ground motion records. The results indicated that roof drifts and plastic deformations reduce with increasing shear wall ratios, but the rate of decrease is lower for higher shear wall ratios. Buildings with 1.00% shear wall ratio have significantly lower roof drifts and plastic deformations when compared to buildings with 0.00% or 0.50% shear wall ratio. Roof drifts and plastic deformations are minimized when the shear wall ratio is increased to 1.50%. After this limit, addition of shear walls has only a slight effect on the seismic performance of the analyzed buildings.

An analytical study was performed to evaluate the effect of shear wall ratio on the dynamic behavior of mid-rise reinforced concrete structures. The primary aim of this study is to examine the influence of shear wall area to floor area ratio on the dynamic performance of a building. Besides, the effect of shear wall configuration and area of existing columns on the seismic performance of the buildings were also investigated. For this purpose, twenty four mid-rise building models that have five and eight stories and shear wall ratios ranging between 0.51 and 2.17 percent in both directions were generated. These building models were examined by carrying out nonlinear time-history analyses using PERFORM 3D. The analytical model used in this study was verified by comparing the analytical results with the experimental results of a full-scale seven-story reinforced concrete shear wall building that was tested for U.S.-Japan Cooperative Research Program in 1981. In the analyses, seven different ground motion time histories were used and obtained data was averaged and utilized in the evaluation of the seismic performance. Main parameters affecting the overall performance were taken as roof and interstory drifts, their distribution throughout the structure and the base shear characteristics. The analytical results indicated that at least 1.0 percent shear wall ratio should be provided in the design of mid-rise buildings, in order to control observed drift. In addition / when the shear wall ratio increased beyond 1.5 percent, it was observed that the improvement of the seismic performance is not as significant.

Nonlinear time history analysis is increasingly being used in the design of tall steel structures, but member sizes still must be determined by a designer before an analysis can be performed. Often the distribution of story strength is still based on an assumed first mode response as determined from the Equivalent Lateral Force (ELF) procedure. For tall buckling restrained braced frames (BRBFs), two questions remain unanswered: what brace distribution will minimize total brace area, while satisfying story drift and ductility limits, and is the ELF procedure an effective approximation of that distribution? In order to investigate these issues, an optimization algorithm was incorporated into the OpenSees dynamic analysis platform. The resulting program uses a genetic algorithm to determine optimum designs that satisfy prescribed drift/ductility limits during nonlinear time history analyses. The computer program was used to investigate the optimized distribution of brace strength in BRBFs with different heights. The results of the study provide insight into efficient design of tall buildings in high seismic areas and evaluate the effectiveness of the ELF procedure.

In reality, dynamic response of a structure supported on a compliant soil may vary significantly from the response of same structure when supported on a rigid base. A parametric study is conducted for the analysis of the variation in the global and the local deformation demands caused by the inertial soil-structure interaction effects. For the purposes of the study, nonlinear dynamic analyses are performed on 7 steel moment-resisting frame models, which are prepared by the virtue of fixed-base and flexible-base (interacting) conditions. Foundation is modeled with the Truncated Cone Model (Wolf, 1994) with the frequency independent coefficients. Free-field earthquake acceleration records are selected to conform to NEHRP equivalent Site Classes C and D. The study is limited to the structures founded on surface rigid mat foundations subjected to vertically propagating horizontally polarized coherent shear waves. Statistical analysis based on multiple linear regression procedure is performed to represent the variation in the response. Within the scope of the study, the wave parameter and the aspect ratio are observed to be directly proportional to the variation in the response, as a general trend. Maximum beneficial contribution of the SSI is found to be 6% in both global and local deformation demands. In addition, the contribution of inertial interaction effects is found to be in a decreasing trend for the increasing levels of ductility demands. Finally, upper limits of wave parameter for H/R=0.5, 1, 2 and 3 are calculated where the variation in the demands are capped at 1.0.

Prior to this study, to our best knowledge, no cast-in-place, older-type RC building has ever been subjected to near-field strong ground motions from three major earthquakes. This happened in an indirect way in Turkey over a time span of eleven years. Three identical buildings belonging to Ministry of Public Works and Resettlement (MPWR) that had been built to the same design templates, experienced March 13th 1992 Erzincan earthquake in Erzincan, November 12th 1999 D&uuml / zce earthquake in Bolu and May 1st 2003 Bing&ouml / l earthquake in Bing&ouml / l, respectively. The ground motion sensor stations were fortuitously nearby in an adjacent single-story building in Bolu and Bing&ouml / l. The station in Erzincan was in a single-story building about 2 km away from the case study building but we assume that the record applies to the building there. These three data represent characteristics of near-field ground motions and the distance of the sensor stations to the nearest fault trace was less than 10 km. The buildings sustained varying degrees of damage during the earthquakes and their damage survey was employed through site investigations. Given that the damage information, input motions, design drawings and material properties of the buildings are all known, this provided an opportunity to predict the structural damage to these buildings by proper modeling using the tools of current computational performance assessment procedures. In this circumstance, three dimensional (3D) analytical models of the MPWR buildings have been performed. Bi-directional excitations have been applied to the models by nonlinear time history analyses (NTHA). The results illustrate that NTHA are capable of indicating the occurrence of shear failure in captive columns / however, they overestimate the global damage level for all buildings. The overestimation is more significant in Erzincan case where the building sustained a pulse-type motion without significant distress.

Although performance based assessment procedures are mainly developed for reinforced concrete and steel buildings, URM buildings occupy significant portion of building stock in earthquake prone areas of the world as well as in Turkey. Variability of material properties, non-engineered nature of the construction and difficulties in structural analysis of perforated walls make analysis of URM buildings challenging. Despite sophisticated finite element models satisfy the modeling requirements, extensive experimental data for definition of material behavior and high computational resources are needed. Recently, nonlinear equivalent frame models which are developed assigning lumped plastic hinges to isotropic and homogenous equivalent frame elements are used for nonlinear modeling of URM buildings. The work presented in this thesis is about performance assessment of unreinforced brick masonry buildings in Turkey through nonlinear equivalent frame modeling technique. Reliability of the proposed model is tested with a reversed cyclic experiment conducted on a full scale, two-story URM building at the University of Pavia and a dynamic shake table test on a half scale, two story URM building at the Ismes Laboratory at Bergamo. Good agreement between numerical and experimental results is found. Finally, pushover and nonlinear time history analyses of three unreinforced brick masonry buildings which are damaged in 1995 earthquake of Dinar is conducted using the proposed three dimensional nonlinear equivalent model. After displacement demands of the buildings are determined utilizing Turkish Earthquake Code 2007, performance based assessment of the buildings are done.