This paper examines a newly developed seismic force-resisting System. To achieve improved seismic performance, the Strongback System combines aspects of a traditional concentric braced frame with a mast to form a hybrid System. The mast acts like a Strongback to help resist the tendency of concentric braced frames to concentrate damage in one or a few stories during severe seismic excitations. The purpose of the Strongback System is to promote uniform story drifts over the height of a structure. For this purpose, in this paper, the design principles for achieving the desired goal, along with a new relationship for controlling the amount of story drift uniform index for this System is presented and the nonlinear dynamic behavior of structures 3, 6 and 12 stories with three seismic force-resisting System with different configuration at the intersection of the braces to the beam under seven acceleration of far and seven acceleration of near field for achieving the correctness of the design principles and comparing the effects of the near and far field earthquakes has been studied. The Strongback bracing System is specifically designed to prevent the uniform story drift and alleviate the soft-story mechanism [2]. The design procedure is such to keep strong-back aspects elastic and stress ratio less than 0. 5. Although the seismic codes specify limits for story stiffness and resistance ratio, this limitation does not guarantee to avoid damage concentration. It should be noted that the concept of uniformity is a relative concept and all stories can never have equal and uniform drift in a structure under earthquake. However, a structure can be designed such that the drifts are distributed uniformly in all stories approximately. For uniform story drift and prevention of soft-story in this System, it is not just enough to keep the stress ratio less than 0. 5 so as to completely design this System, and the necessary examinations were carried out to reach a relation between conventional braces and aspects of Strongback. In addition, studies by Lai and Mahin [2] show that the simple design strategy used does not result in adequate member sizes near the top of the Strongback Systems and limited yielding of the Strongback spine occurs at these levels. According to the ratio of the braces length and Dimensions of their sections, when the stress ratio in Strongback should be less than 0. 5, this result was obtained some limitation must be considered about conventional braces stiffness ratio and the aspects of Strongback. Therefore, by considering the issue of elastic state of the components of Strongback in earthquakes, conventional braces were designed for code earthquakes force and stiffness ratio of Strongback braces to conventional braces is in each story equal to or more than 2. 5 and section of Strongback zipper member was considered equal to section of Strongback brace member in the story. During these tests, which were performed using the trial and error method, various earthquakes were used to perform the nonlinear time history analysis and various values were considered for the stiffness ratio of Strongback braces to conventional braces and were evaluated, which revealed that the stiffness ratio of 2. 5 would cause a more uniform distribution of drift along the height of the structure and was the basis for the design of the braces of this System. Results show that the proposed design principles, which are proportional to the stiffness ratio of bracing, are presented by providing an index of uniformity distribution error in structures 3, 6 and 12 stories, which occurred less than 6, 4. 8 and 8. 6 respectively. Also by creating a difference of 0. 5% between the maximum and minimum of the story drift ratio in most of the structures studied, it has been able to hold the Strongback truss in elastic to nonlinear analysis, reduce the concentration of deformations and prevent the creation of a soft story structure.

One of the most popular lateral load resisting Systems is the concentric bracing. However, despite the unique advantages of the System, it has irregular and unstable hysteresis cycles because of differences in compressive and tensile strength. Hence, many studies are devoted to improve these braces to achieve an ideal symmetric elastoplastic behavior which has resulted in construction of Buckling-Restrained Braces (BRB). BRBs, although have a much better seismic performance than ordinary bracing, have a main disadvantage (similar to conventional bracing) of producing large nonlinear displacements due to their low stiffness, and consequently they have potential to form soft story. Recently, Strongback Bracing System (SBS), which is a combination of a zip System and an elastic truss System, has been introduced. SBS actually includes two types of features: a rigid elastic truss to tie story drifts over the height of the structure, and a conventional bracing System to dissipate energy. Therefore, this System can prevent or delay probability of soft story by controlling the distribution of floor displacements and the nonlinear demand of the structure. However, the studies conducted on this System are limited, and to the best of the author’, s knowledge performance of this System with BRB configuration under seismic sequences is not yet investigated. In this paper, seismic performance of the SBS System is investigated and compared with the BRB one. First, behavior of these Systems are studied under main shock. Next, seismic sequences are applied on the structures to better understand the behavior of SBS frames compared to BRB. For this purpose, three 4-8-and 12-story frames were designed with two SBS and BRB Systems. BRB elements were used as inelastic braces of SBS System. Nonlinear static analysis was conducted to evaluate the seismic parameters of the structures such as response modification factor and overstrength factor. Also, nonlinear time-history analysis was performed to find maximum and residual response of the structures. In the next step, a fragility analysis was conducted using IDA to estimate performance of the structures under mainshock and seismic sequence for different performance levels. 3 performance levels were selected for SBS and 4 performance levels for BRB which show the elastic to global collapse of the structures. The results of static analysis showed that the SBS System has a uniform distribution of displacement in the height of the structure, which prevents the formation of soft story. In all analyses, SBS showed a superior performance, especially in 4 story structure. Also, SBS frames showed higher response modification and overstrength factors. Results of dynamic analysis showed that the 4-story SBS structure was much less vulnerable to seismic sequences compared to the BRB one. However, the performance of SBS System decreases with increase in the height of the structures, such that 12-story frame experienced large deformations and collapsed under lower seismic demands than BRB frame. This was due to buckling of some elements in rigid truss which led to concentration of demands in these elements. Therefore, more stringent provisions are needed for design of taller structures with SBS System.

This study explores the motivational components within teacher rating Systems and their impact on professional growth motivation. Employing a Systematic review approach, it investigates texts pertaining to teacher rating Systems, motivation, and professional development literature. By examining various texts and research findings on teacher motivation, factors influencing teacher ratings based on general, specialized, and professional competencies, as well as experience, are identified. Drawing parallels with Herzberg's motivational theory, this study provides recommendations to bolster teacher motivation and job satisfaction through improvements in the rating System.

Steel bracing frames are efficient Systems for resisting seismic loads. However, multi-story steel bracing frames tend to concentrate seismic demands in one or more stories in response to severe ground vibrations. Therefore, in recent years, mechanisms have been presented to distribute inelastic demands over the height of the structure. Strongback braced frame is one of the efforts made in this field. This System, using an elastic truss at the height of the structure, redistributes demands to other floors. In most studies conducted on conventional steel braces, they have been used as energy dissipation elements, while due to the buckling of the braces, adequate energy dissipation is not seen in these structures. In this study, the possibility of improving the behavior of a buckling-restrained braced frame with a crescent-shaped brace was evaluated. Initially, to provide more flexibility in design, a three-part brace or trapezoid brace was introduced, and finally, the possibility of improving the behavior of a Strongback braced frame by adding a crescent-shaped or trapezoid brace was evaluated with Nonlinear static analysis. The results showed that the use of a crescent-shaped or trapezoid brace, while improving the energy dissipation of the structure by up to 440.9% and increasing the shear capacity of the structure by up to 57%, did not significantly increase the stiffness of the structure (maximum 14%) and the forces generated in the elastic truss elements formed a uniform distribution over the height of the structure.