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Understanding the behavior of structures during earthquakes is crucial for ensuring safety. Despite their significant impact on buildings, infill walls are often overlooked in seismic assessments, contributing to the complexity of a structure. Because of their intricate nature and modeling difficulties, infill walls are frequently excluded from seismic models. However, given the prevalence of reinforced concrete buildings with various infill wall materials in earthquake-prone areas, it is essential to incorporate infill walls for a more realistic evaluation of seismic behavior. This study scrutinizes a building that sustained damage in the Izmir earthquake in Turkey. The building was represented in four distinct models using the SAP2000 V24 finite element program: without infill walls, with porotherm clay blocks, burnt clay brick, and autoclaved aerated concrete blocks. Real parameters of the building were utilized in the modeling process. Upon comparing the results of the time history analysis, it was observed that the presence of infill walls had a positive impact on various building properties, including period, ground floor shear force, column bearing capacity, and inter-story drift ratio. Additionally, infill walls increased base shear forces on the ground floors and the overall base shear force. Notably, similar outcomes were obtained with porotherm clay blocks and burnt clay brick as infill wall types, while autoclaved aerated concrete blocks exhibited lower stiffness than other infill wall models. [ABSTRACT FROM AUTHOR]

The structural behavior prediction of the multistory reinforced concrete (RC) buildings with masonry infill walls (MIWs) during earthquakes is challenging. This paper presents a nonlinear macromodeling strategy seeking a simple, reliable, and low-cost computational analysis of the multistory RC buildings that comprise MIWs, and that use frames or shear walls (SWs) for resisting the lateral load. The strategy employed four plastic hinge (PH) models for tracking the deformations (flexural, shear, and torsion) of the frame elements and joints, a multilinear plastic link for modeling the MIW, and a nonlinear multilayer shell element for modeling the SW. A flexural PH model characterized by discretization into fibers, a recommended position, and an iterative estimating for the PH length using a distinct formula for each loading level was proposed. This strategy was validated through eleven macromodels investigating four bare frames, four MIWs frames, and a SW where the average ultimate lateral load error was 9.2%, 3.6%, and 0.4%, respectively. Finally, the structural behavior of real ten-story buildings with/without MIWs was investigated. The results showed that the MIWs increased the shear capacity and the lateral stiffness with an average of 44.3% and 118.6%, respectively. Also, both the frames buildings with MIWs and the bare SWs buildings showed approximately equal lateral load capacities. Local damages in the RC vertical elements and yielding of the MIWs were recorded simultaneously. However, the MIWs yielding (and also failure) occurred earlier for the frames buildings compared with the SWs buildings in which the stress was relaxed in their MIWs. [ABSTRACT FROM AUTHOR]

Frequent unintentional explosions in industrial facilities and deliberate demolition of commercial buildings have resulted in significant financial damages, leading to increased demands on structural engineers to enhance blast resistance design methods. Therefore, comprehending the impact of blasts on structure performance is crucial. The study examined how a standard 21-storey reinforced concrete building structure responded to blast loads from TNT explosives of varying charge weights (100, 300, and 500 kg) at different standoff distances (10, 20, and 30 m). The research focused on the effects of structural walls at the core as well as peripheral infill walls. Using a three-dimensional finite element approach with nonlinear dynamic analysis via SAP2000 software based on Indian Standard specifications (IS:4991, 1968), key response parameters such as acceleration, displacements, and velocities were analyzed over time. It was observed that acceleration and velocity reached peak values earlier than displacement. The building's blast resistance with structural walls was deemed satisfactory; furthermore, it improved with the installation of infill walls. [ABSTRACT FROM AUTHOR]

Most of the Italian infrastructures have been built since the mid‐twentieth century. Prestressed concrete (PC) has been widely used, especially for bridges and viaducts. These structures have proved effective over time, but their performance could be affected by degradation phenomena (i.e., corrosion of the tendons and residual prestressing) or construction defects (i.e., grouting of the ducts), which need to be accurately modeled. This paper focuses on the flexural response of two reduced‐scale, posttensioned, PC bridge girders, prestressed with two different jacking forces and tested under four‐point bending configuration. Four multidimensional numerical models were developed to simulate the experimental behaviors of the selected specimens, using two alternative computational strategies, namely, the finite element method (FEM) and applied element method (AEM). Three FEM modeling were considered, ranging from one‐dimensional lumped‐plasticity models to two‐dimensional and three‐dimensional (3D) spread‐plasticity models. Besides, 3D AEM models were developed into another software package. The accuracy and the computational costs of the two numerical strategies are discussed in this paper. Also, the main features of each numerical modeling technique are addressed, including comparisons between numerical and experimental global response data as well as the statistical characterization of the model error. Based on these different features, the authors also suggest the most suitable numerical strategy for future studies on PC girders. [ABSTRACT FROM AUTHOR]

Within the scope of the study, three-story, ten-story and fifteen-story steel structures with symmetrical and L-shaped asymmetrical story shapes and a single-story industrial building model structures were analyzed with the SAP2000 software as a reference with StaSTEEL, which is frequently used in the market. There are no studies in the literature with StaSTEEL at the time of this research. There are 7 types of buildings examined in the study. The results of the software were compared in terms of floor weights, natural vibration periods and axial, shear and moment stresses on the elements. In addition, by examining the interfaces of the programs, data entry for the user, examining the results and how and to what extent the needs are met for outputs. The rules stated in Turkish Seismic Code-2018 and Turkish Steel Structures Regulation-2016 were used for structural analysis. It has been observed that the analysis outputs of the two package programs are similar. The most differences for N, V and M in the internal forces that occur regardless of whether they are symmetrical or asymmetrical, low-rise or multi-story are 3%, 3.5% and 2.7% respectively. However, it was observed that the StaSTEEL software was easier for both data entry and examining of the analysis results. In addition, it was concluded that the prepared calculation reports were more detailed and highly visual. [ABSTRACT FROM AUTHOR]

Earthquakes are natural disasters that directly or indirectly affect human life. Performance-based design of reinforced concrete structures has become increasingly important due to the negative effects of earthquakes in recent years. In current earthquake regulations, instead of force-based methods, deformation-based design has started to be used. Reinforced concrete elements must be understood correctly in order to design reinforced concrete structures correctly. The element behaviors depend on the determination of the section behaviors. Within the scope of the study, the behavior of the column sections was obtained from the moment-curvature relations considering the non-linear behavior of the materials. Moment curvature relations of reinforced concrete columns for different axial load levels were obtained by considering the Turkish Building Earthquake Code (TBEC 2018) concrete model. The effect of changing parameters on column behavior was evaluated in terms of effective section stiffness. In this study, reinforced concrete type buildings with 3, 5, 7 and 10 floors were examined. Nonlinear static pushover analysis method, which is one of the methods based on shape change, was applied by taking into account the principles of the Turkey Building Earthquake Regulation (TBEC 2018). Nonlinear material behavior of columns and beams, section designs and calculation of plastic hinge properties were made with XTRACT program. This information obtained from XTRACT program was defined in the SAP2000 program. Building models and analyzes were made with the SAP2000 structure and analysis program. As a result of the analysis, the change in the effective section stiffness of the structural system elements with the increase in the number of floors in reinforced concrete buildings was examined. In addition, the relationship between the base shear force and top displacement resulting from the static pushover analysis of the number of floors change was investigated. Static pushover analysis showed that the ratio of the base shear forces to the weights of the buildings (Vt/W) decreased as the number of floors of the building increased. As the total height of the building, that is, the number of floors, increased, the top displacement values corresponding to the performance point increased. [ABSTRACT FROM AUTHOR]

In high-rise buildings, shear walls are an important structures feature for sustaining lateral forces. The production of prefabricated steel frames buildings will effectively overcome iron and steel spare capacity, allowing the building sector to recover the industrial revolution. As an advanced kind of flexural rigidity steel plate shear walls (SPSWs) can withstand majority of the load in the frame structure, boost the preliminary lateral toughness and lateral bearing strength, and serve as a first protective barrier until the main frame is demolished, reducing the main frame's failure level and improving the structure's failure resistance. When structures are subjected to external loads such as earthquakes, wind, and other natural disasters, shear walls can be used to increase the structure's strength and safety. The main focus of this research is to use SAP2000 to compare and analyze two different types of shear walls in two different 7-story buildings. Two structural members, one having a honeycombed steel sheet sandwiched between two thin steel plates shear wall and the other having RCC shear wall are compared based on lateral loading parameters (base shear, displacement story-drift etc.). Using SAP2000, the effects of three main parameters were investigated by Pushover analysis and Time history analysis. From the complete analysis, shear wall with honey combed thin plates is proved to be better against seismic and wind loading as compared to RCC wall as well as honeycombed sheet sandwiched between steel plates is economical and gives more area to the story by occupying less space. [ABSTRACT FROM AUTHOR]

Superelastic shape memory alloys (SMAs) introduce supplementary energy dissipation with minimal residual deformation, which is desired in earthquake engineering–related applications (e.g., SMA bracing systems or SMA-based isolation systems). An appropriate phenomenological model of SMA flag-shaped hysteresis is essential to simulate the seismic response of structures equipped with such devices. In the structural analysis and design software SAP2000, no element is available specifically for modeling SMAs. The CSi knowledge base webpage suggests a parallel combination of elementary multilinear-elastic (MLE) and multilinear-plastic (MLP) link elements. This modeling strategy, widely used in the literature, can be affected by the cumulative damage in the MLP link elements after the first plastic excursion. As demonstrated in this technical note, the cumulative damage in MLP elements leads to incorrect modeling of the SMA flag-shaped hysteresis in nonlinear time-history analysis (NLTHA). This issue encountered in the model suggested in the CSi knowledge base webpage is resolved by an alternative modeling strategy proposed in this work, which makes use of parallel MLE and MLP link elements along with series gap and hook spring elements available in SAP2000. The proposed approach not only eliminates the cumulative damage of MLP links over repeated cycles, but also lends itself to a more general representation of the flag-shaped hysteresis of SMAs than do other formulations proposed in the literature, thus proving to be a simple and versatile modeling strategy. [ABSTRACT FROM AUTHOR]

In order to explore the mechanical performance of negative pressure tube jacket during construction, the finite element analysis software SAP2000 was used to establish the model of negative pressure tube jacket. According to the force analysis of the negative pressure tube jacket rectification, the calculation is that the negative pressure tube does not touch the bottom synchronously, gradually reducing the load on the jacket legs, and simulating the weakening process of the negative pressure cylinder supporting the jacket legs after the suction pump system produces suction, it is suggested that in the process of rectifying the deviation of negative pressure tube jacket, the pressure difference inside and outside the tube should be less than 7.5 kPa, leaving a certain safety reserve; the inclination angle of the jacket should not exceed 0.8° during the construction. Comprehensively consider the soil resistance, the bearing capacity analysis was carried out for the construction of the negative pressure tube jacket. Under the action of wind, wave, current and dead weight load, the pull -up force or down force of the jacket leg was calculated and applied to the negative pressure tube. Under the action of the three working conditions, the pulling force and pressing force of the jacket to the negative pressure tube meet the requirements of bearing capacity. [ABSTRACT FROM AUTHOR]

The present paper serves the purpose of presenting an extinct type of 18th-19th century masonry building, that of an ox-stable, situated in one of Europe's most secluded areas: The Holy Monastery of Pantokrator in Mount Athos Peninsula. Architectural drawings and surveying plots of its current state can serve as a record and reference of this UNESCO site for scholars. Adding to that, an elaborated proposal for the reuse of the building is presented together with technical drawings, which were approved by Greece's Central Archeological Council. The masonry rectangular building is founded on natural rock with masonry pillar footings of different heights. Hence, the elevation irregularity and the different elevations of the footings of the structure present an additional challenge for the structural analysis. Structural analysis with a finite element (FE) model of the restored structure was executed with SAP2000 software. Performing lateral force and response spectrum analyses, stresses and deformations at critical points of the structure were calculated. Comparing a set of simplifying structural checks with the elastic FE analysis performed, it was concluded that the proposed design is effective in improving the earthquake performance of the structure. [ABSTRACT FROM AUTHOR]

This paper presents explicit evaluation of the safety and reliability of structures to obtain the actual performance of the structure numerically which will finally help designers to not only protect life, but also to minimize damage of the structures to an acceptable level. To do so, nonlinear finite element analysis of the frame is conducted, and results from lumped plasticity and continuum-based modelling approaches were compared with documented experimental results. The capability of each numerical model to capture the load deformation relationship and failure pattern is studied. Moreover, a parametric study is performed for selection of suitable material model which could depict the actual response of the frame for both considered numerical modelling tools. From this study, the analysis result of the lumped plasticity based model in SAP2000 was seen to be more realistic to the experiment result when the user-defined hinge model with confined nonlinear concrete property, non-linear rebar property with consideration of crack section as per the codal provision was performed. The frame remodeled with continuum mechanics based approach in LS-DYNA modelling tool could capture the experimental results with higher accuracy. In addition, among several material models available, Continuous surface cap model is recommended to be used for quasi-static analysis of structures since it can capture the performance of structure with significant accuracy. [ABSTRACT FROM AUTHOR]

In the hilly region due to scarcity of the plain area, buildings like set back-step back are more often used and also as a big surge in the telecommunication industries, rooftop tower adaptation is very common story nowadays. In the present study an analogy has been drawn to find out the influence of the rooftop telecommunication tower on the setback-step back building resting on ground at 20° and 30° slopes. A dynamic analysis has been performed and compared on the 4 legged angled section telecommunication tower which is located on the roof top of set back-step back building by varying positions of tower with the existing host structure built up on ground slope of 20° and 30° in both directions (X and Y). [ABSTRACT FROM AUTHOR]

In this paper a general methodology for calculating the centres of rigidity in multi-storey asymmetric buildings is proposed, which is applicable to orthogonal as well as to non-orthogonal diaphragm systems with complex topology and possible coupling of diaphragms along with consideration of very general load conditions, including gravity and modal loads. The methodology is presented in two alternative forms: (a) In the standard form, matrix relations have been developed which can be directly included to any new or existing programming codes for analysis of building structures, (b) In the alternative form the methodology can use the results of any standard programs for static analysis of building structures, in addition with a small post-processing effort that can be achieved by only few hand calculations, thus becoming significantly simpler than the methodologies that currently exist. A numerical example presents the individual steps of a comparative application of the standard and alternative forms of the methodology, while two additional numerical examples demonstrate the simplicity and efficiency of its alternative form. [ABSTRACT FROM AUTHOR]

This research proposes the inelastic buckling and modal analysis to design optimal shape and size through UL700 steel arch-grid unit module which is for localized reinforcement of soft ground. The optimal arch-grid design is achieved among its most efficient design possibilities such as different plate type, extended grid, multi-story grid, combined grid. The steel arch-grid unit module is composed of a vertical member and a board member combined with the top and bottom sides of the said vertical member, including the horizontal member equipped with multiple arm parts combined with the center part into one body in the shape of a cross. The construction method for reinforcement of soft ground is proposed in detail in this research. Numerical experiments are provided to survey optimal shape and size of arch-grid structures with differential models applied to buckling analysis, modal and static load, in consideration of both linear and nonlinear behaviors, by using SAP2000 version 15.0.1 software. With sufficient features of steel arch-grid for supporting structural foundations, this research suggests the possibility of requiring more studies and of providing more applications in the field of constructional structures. [ABSTRACT FROM AUTHOR]

Water towers are widely used in our society as one of water distribution facilities within water network systems. In the event of a severe earthquake, however, a single plastic hinge that occurs in a water tower could cause its total collapse before nonlinear resources of the rest of the tower remains fully utilised. This research presents an innovative technique for the assembly of a water tower using the slits in its reinforced concrete shaft for the purpose of mitigating the seismic response. Slit shafts were designed to have four slits at 90° intervals along the full height of the shafts. The shaft parts were connected to each other at the bottom, top and every five meters with coupling beams. The slit width was used as a variable in this study which varied between 50 mm and 2000 mm. The nonlinear seismic performance of the proposed slit towers was analysed by means of a finite element approach with respect to soil types defined in Eurocode 8 and seismic behaviour were compared to the solid water tower. A detailed observation of the compression and tension stress distributions with respect to the slit width was performed. The obtained analytical results revealed that slit width in the reinforced concrete tower affect the failure mode and stiffness of a water tower significantly. With an appropriate design, the conversion of a solid water tower into a slit tower can significantly increase its ductility under seismic action without significantly compromising its bearing capacity. The results showed that contours of tension and compression stress intensity in shafts, which could lead to a failure of water towers, highly depended on the slit width. In the solid water tower, the stress concentration dominated at the base of the shaft, however in the narrow slit water towers the stresses were equally distributed along the height of the shafts. Also, the stresses were mostly concentrated at the top of the shafts in the wide slit water towers. Conclusively, the results provided useful information regarding the compression stress distribution along the slit shafts in the water towers which can be used in obtaining an optimum slit shaft design for different soil types. [ABSTRACT FROM AUTHOR]

This study investigates an idealized ground supported reinforced concrete rectangular water tank under earthquake excitation. A linear three-dimensional finite element analysis and SAP2000 software have been used to predict tank response. The variable analysis parameters considered are the aspect ratio (tank height to length ratio) and tank water level, while the tank wall thickness is taken as a constant. The convective and impulsive masses are also represented by spring-mass model in the time history analysis for El-Centro earthquake ground motion record. Five tank models with a capacity of 216, 288, 360, 432 and 504 m3 were developed and analyzed for hydrodynamic and hydrostatic effects. In general the results show that, there is a smooth increase in the moment and displacement of both hydrostatic and hydrodynamic analysis with a decrease in aspect ratio. The top displacement and moment for the hydrodynamic effects are greater than the hydrostatic results and it is observed that the maximum hydrodynamic moment is 91.3% higher than the corresponding maximum hydrostatic moment. Likewise the displacement obtained from hydrodynamic analysis is 63.58% more than the corresponding hydrostatic value. [ABSTRACT FROM AUTHOR]

To obtain deformation rules of steel reinforced concrete structure under stress, this study explored the crack formation in construction period. A novel structure system - steel reinforced concrete structure with shear wall and truss at the bottom was analyzed using on-the-spot test in combination with theoretical simulation analysis with SAP2000 software. It was found that, factors influencing crack formation of steel reinforced concrete structure in construction period included construction load, creep of concrete, shrinkage of concrete, displacement of bond of section steel and concrete as well as leveling. In the construction period, the simulated results and the measured results were highly fitted under the influence of time-variant characteristics such as compressive strength, elasticity modulus, creep and shrinkage. Through processing and analyzing the measured data, we obtained the development rules of crack formation of steel reinforced concrete structure with different strength grades as well as deformation rules of time-varying structure system in construction period, figured out the reason for the difference between the simulated results and the measured results, analyzed the deformation of structural components under stress in construction period and proposed some suggestions. This work is beneficial to ensure safe and high-efficient operation of construction. [ABSTRACT FROM AUTHOR]

One of the main purposes of designing buckling-restrained braces is that the entire lateral load is wasted by braces and the entire gravitational load is moved to the foundation by beams, and the columns can be moved to the foundation. In other words, braces are designed for lateral load. It should be noted in the implementation of the structure that the implementation of various parts of the structure must be such that the buckling-restrained braces would not bear the gravitational load. Also, this type of brace was investigated under impact loading, and the design goals of designing method (direct motion) are controlled under impact loading. The results of dynamic analysis are shown as relocation charts of floors and switching between floors, and the results are compared. [ABSTRACT FROM AUTHOR]

According to the ASME-359 code, a scaled-down structure of Reinforced Concrete Containment Vessel (RCCV) of Advanced Boiling Water Reactor (ABWR) building is constructed for the seismic test on the shaking table. Several acceleration time history satisfing design response spectrum with different magnitudes are used in the test. Besides, the numerical finite element model of RCCV is built by SAP2000 for calculating the dynamic responses numerically. [ABSTRACT FROM AUTHOR]

Highlights: [•] Seismic failure mechanisms expressed by a single failure mode interaction surface. [•] Vertical load variation and zero-moment position affecting the lateral strength of URM piers. [•] Equivalent frame model with N–V failure mode interaction plastic hinges. [•] Application of the IN2 method for application to URM structures. [•] Comparison between the IN2 method and IDA for URM. [Copyright &y& Elsevier]

The idea that may occur soft storey irregularity is quite common among civil engineers, if the ground height is more than the other floors in the building. The formation of a soft storey is found due to many different reasons such as structural changes between floors in buildings or between floors the use of different flooring system. However, one of the most common causes of the formation of a soft storey in reinforced concrete structures, It is usually avoidance weave of the wall with the aim of creating large areas as much as possible and provide incomegenerating commercial areas on the ground level shops, restaurants, car dealerships, banks and so on. Even if buildings in this case are designed in accordance with the Turkish Earthquake Code (TEC-2007), they have suffered from severe damage, and even destroyed in earthquakes due to soft storey irregularity. It is illustrated with an example given that they cannot determine the soft storey irregularity of a building. Suggestions are given for soft storey criteria proposed of TEC-2007 on the subject. [ABSTRACT FROM AUTHOR]

With the development of the enhanced materials and techniques for analysis of bridge, long span cable-supported bridges are introduced. Cable-supported bridges comprise both suspension and cable-stayed high strength bridge systems. Both these forms of cable-supported bridge are flexible structures in behavior. These flexible systems are susceptible to the dynamic effects of wind and earthquake loads. With the increasing span of the bridge, the flexibility of the bridge is escalating. In this paper, an attempt is made to enhance the rigidity of long span bridge . For enhancing the rigidity of the bridge in lateral and vertical directions, a different configuration of the cable-stays of long span cable-stayed bridge is considered. To understand the response of the long span cable-stayed bridge, the modal time history analysis is carried out in SAP2000 software. The parameter considered to analyze the cable-stayed bridge is dissimilar to cable-stays configuration. The behavioral response of the bridge is presented in the form of a time period in lateral and vertical direction for structural members of the bridge. [ABSTRACT FROM AUTHOR]

In this article the effect of stresses is studied in a dam with a height of 45 m and foundation soil system from self weight of the new concrete and a 150 C temperature increase of the newly added concrete caused by a dam heightening. The analysis was performed in the hypotheses of empty reservoir. The meshing for the analysis of the effort conditions for the system dam-soil foundation was made with plane isoparametrics elements of class C, named "PLANE" from the library of elements of the SAP2000 program, and was performed automatically with manual corrections at the upstream toe and downstream toe of the dam. The analysis was performed in the hypothesis of the plane deformation condition and linear elastic behavior of materials. [ABSTRACT FROM AUTHOR]

Pounding occurs when the adjacent buildings start vibration out of phase during the seismic activity which causes collision amongst the adjacent buildings. There are many mitigation techniques to avoid or minimize the effects of pounding including the provision of minimum separation gap between the adjacent buildings. Although all codes have provided the minimum separation gap requirements for the buildings, still a lot of study is required on this topic. This research aims at finding the minimum gap requirement for midrise buildings in Pakistan. Adjacent Buildings with different geometry and height are modelled in Sap2000 software with varying gap elements. Pushover and In-elastic time history analysis of these buildings are carried out using ground motion of Kashmir earthquake. Buildings are assumed to be resting on stiff soil. Material and sectional properties are also remained same for all cases. In order to reduce the pounding effects of two buildings, they were attached with each other and top displacements of buildings were compared with separate buildings with inadequate gap. Column shear, maximum peak displacements and square root of sum of squares of maximum peak displacements were studied and the results were plotted graphically. It was found out that pounding can occur up to separation gap of six inch. Maximum pounding occurs at the top floor level of smaller building. The requirement for minimum gap in UBC 97 is found out to be conservative. [ABSTRACT FROM PUBLISHER]