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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]

Within structural engineering, bridges demonstrate how the practical import of scientific hypotheses becomes clear to humanity. Engineers use computer simulations and models to anticipate how the bridge will react under various stresses and what its response is likely given all sorts of environments over its life span. The construction of the Nongsa Pura Bridge in Batam, which showcases cutting-edge civil engineering accomplishments customized to local requirements, represents a critical turning point in the region's infrastructure improvement. This paper aims to analyze the deflection of a Nongsa Pura Planning Simulation using SAP2000 software. This research uses secondary data and the author's assumptions as necessary data to design a bridge. The results of this research are deflection values for the main girder, transverse girder, and longitudinal girder. In the main girder, the most considerable deflection value is 0,0778724 m. In contrast, in the transverse girder, the most considerable deflection value is 0,034118 m, and the longitudinal beam has the most considerable deflection value of 0,077809 m. [ABSTRACT FROM AUTHOR]

Abstract Elevated water tanks are considered crucial infrastructure due to their significant role in supporting essential services. A strong ground motion may result in a failure or significant damage to a reinforced concrete shaft of an elevated water tank because hysteric energy dissipation is limited to the formation of plastic hinges at the base of the shaft, while the nonlinear properties of the rest of the shaft remain underutilised. The innovative system of assembling RC shafts for elevated water tanks using a slit wall technique was developed to enhance energy dissipation along with the shaft height by introducing slit zones. The comparative nonlinear dynamic analysis between three-dimensional models of elevated water tanks with different shaft diameters and heights was conducted using SAP2000 software. The results of elevated water tanks with slit and solid reinforced concrete shafts were compared. The research findings showed that during a seismic event, the slit zones increased the ductility of the shaft, reduced stress concentration in the lower part of the shaft, and provided uniform stress distribution throughout the shaft's height. The effect of the innovative system is especially noticeable in the elevated water tanks with tall and slender shafts.

This study deals with the use of finite element analysis to study the response of an RC building that has inclined supporting leads in the foundations. Several RC buildings were studied to evaluate the seismic performance of these buildings under the influence of change in three parameters (the degree of inclination of the foundations (0°, 10°, 20° & 40°), the storey number (8, 10, 12, 16 & 20 storey), and the span length (4, 5 & 6 m)). All buildings were analyzed using the SAP2000 software using the time history analysis method under the influence of the EL-Centro N-S 1940 earthquake acceleration record. The results were shown the values of the base shear, time period and roof displacements decreased by 23%, 33% and 55% respectively, when the degree of foundation inclination of the building increased from 0° to 20°, while these values increased by 68%, 53.28% and 137.6% respectively, when the No. of stories increased by 50%. The increase of base shear due to increase the height of building, also the increase lateral displacements of the buildings. The increases in time period due to decrease the stiffness of RC building and it have more displacements at tip of buildings.

This study focuses on the design procedure and development of the unbonded fiber-reinforced elastomeric isolator (UFREI) and its application to prevalent masonry building practices in developing countries. The proposed design procedure caters to the development of rectangular UFREIs with or without modifications, considering an improved shear behavior formulation. Afterward, the proposed design procedure is used to design the isolation system for a pre-existing base-isolated masonry building located in the Tawang district in the northeastern state of Arunachal Pradesh in India. Three different configurations of the above building [i.e., fixed base, isolated using square UFREIs, and isolated using modified rectangular UFREIs (MR-UFREI)] are considered for a comparative response analysis under a set of probable ground motions during a service period of 100 years. The building is modeled in SAP2000, where it is subjected to nonlinear time-history analysis under the considered set of ground motions. The masonry walls are modeled as nonlinear layered shell elements, and concrete floors as rigid diaphragms. An improved shear formulation of UFREI is used to model the isolation system as a combination of a multilinear elastic spring and a dashpot. Major response parameters, i.e., floor accelerations, isolator displacement, interstory drift ratio, etc., are investigated, and a significant improvement is witnessed throughout with the use of the MR-UFREI isolation system. The stress–strain distribution and concentrations in the masonry structure and isolation system are also investigated. These distributions are further used to quantify the fatigue losses to the elastomer layers used in the isolation system during the design period, which is found to be minimal. [ABSTRACT FROM AUTHOR]

Numerical calculations are a standard part of modern structural design. Engineers remain particularly interested in real problems where analytical and numerical solutions can be compared with experimental results. Such cases are typical examples of benchmarks because they are used to verify the assumptions introduced. This study shows in detail how shear stresses affect the deflection of a relatively short and high cantilever when the span-to-height ratio of the cross-section is less than five. Such models are frequently used in the design of cantilevers that support heavily loaded beams, for example in the cement industry (e.g., often as structural elements for a heat exchanger system) or for the assessment of short cantilever limit states that appear during excavation in rock sediments. The models are also suitable for designing the various details and joints in the industry of prefabricated elements. This work analyzes in depth the analytical solutions for the displacement field of the linear elastic plane stress theory with two displacement boundary conditions. Also, the solutions were compared with the beam, two-, and three-dimensional numerical models using SAP2000. The results highlight the fundamental principles and solutions behind plane stress and beam theories, with an insight into the advantages and limitations of such 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]

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

Copyright of Journal of Indonesian Civil & Environmental Engineering / Jurnal Teknik Sipil & Lingkungan is the property of IPB University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In Pakistan, surface water supply for irrigation is decreasing, while water demand is increasing for agriculture production. Also, due to the fast rate of population growth, land holding capacity is decreasing. So, there is a need to develop appropriate technologies and design approaches for small-scale farmers to improve modern irrigation practices. In this study, a hydraulic and structural layout of CPIS was designed for small-scale farmers with some modifications. The hydraulic parameters and structural design of the CPIS were designed using IrriExpress and SAP2000 software, respectively. An economic analysis of the modified CPIS was carried out. The results revealed that in one complete revolution of the whole system, its span slope varied from 2.98 to 0.1%, and the wheel slope varied from 2.35 to −2.4%. The timing setting was 60% for one revolution, and the irrigation depth was 10 mm. When the time setting was reduced from 100% to 10%, the irrigation hours per cycle and irrigation depth both increased. Variendeel type-II trusses were designed for structural purposes using SAP2000 software. This design led to a 17% reduction in weight by lowering it from 1.916 to 1.5905 tons and a 44% reduction in joint count, decreasing it from 32 to 18. Our economic analysis revealed that the structural part of the system is more expensive than the hydraulic, electric and power parts for small-scale design. So, it was suggested that CPIS is suitable for land holdings from 100 to 250 acres, because when the area increases to more than 250 acres, there is no significant change in the cost. A towable system is more economical for small-scale farmers due to its lower cost per acre. This study will be helpful for the optimization of CPISs to improve water use efficiency and crop yield. [ABSTRACT FROM AUTHOR]

The seismic response of safety-related equipment mounted on the head of an advanced reactor, including pumps, control rod drive mechanisms, and reactor monitoring devices, will affect the design and layout of many advanced reactors. High earthquake-induced accelerations in such equipment may challenge their seismic qualification and trigger the need for additional support framing on the reactor head. Base isolation is a design solution that can drastically reduce seismic demands on equipment. This article describes a set of earthquake-simulator experiments conducted on a scale-model of a base-isolated reactor vessel including four representations of head-mounted equipment, with frequencies spanning from 4.5 to 27 Hz. Dynamic responses of the head-mounted equipment, including displacements, accelerations, and strains, were measured in the experiments for three support conditions: conventional, and seismically isolated using single concave Friction Pendulum (SFP) bearings and triple Friction Pendulum (TFP) bearings. Seismic isolation was effective at reducing equipment responses (accelerations, displacements, and strains) with respect to those in the conventionally supported vessel across a range of seismic inputs. Companion numerical studies highlight the accuracy to be expected in the calculation of different response quantities for lightly damped equipment. The importance of characterizing damping in head-mounted, safety-related equipment through physical experiments to support design and risk assessment is made clear through the numerical simulations. [ABSTRACT FROM AUTHOR]

The transitional zone between a bridge and its adjoining roadway, known as the bridge approach, frequently experiences differential settlement. This study employs the threedimensional finite element software SAP2000 V22 to rigorously examine the performance of bridge approach slabs under vehicular loads, with a particular focus on the interaction between the slabs and embankment settlement. Bridge approach slabs and soil are modelled using shell and solid elements, respectively, with the soil characterized by the Drucker-Prager material model. A comprehensive investigation is undertaken to evaluate the effects of various soil and slab parameters on the system's performance, including slab thickness, slab length, approach slab restriction, fill material thickness, and soil's elastic modulus. Furthermore, a sensitivity analysis considering different boundary conditions is also conducted. The outcomes of the analysis include predicted slab deformations and bending moments under design traffic loads. Notably, a correlation is found between increased settlement and approach slab length at the slab's unrestricted boundary, particularly for soils of lower stiffness. The results also suggest that enhancing the compacted fill material thickness and the soil's elastic modulus can reduce slab deflection. The boundary condition and thickness of the slab are identified as key determinants of settlement values. These findings offer valuable insights for engineering professionals aiming to optimize bridge approach slab design, thereby boosting structural integrity and durability. [ABSTRACT FROM AUTHOR]

The Hani Rice Terraces are a famous World Heritage Site. The mushroom houses in the terraced fields have a unique architectural style and national cultural characteristics. This study focused on four traditional villages with the most obvious characteristics of mushroom houses: Azheke Village, Dayutang Village, Yakou Village, and Dayazi Village. A total of 34 mushroom houses were mapped. The forms of the mushroom houses were classified first, and then, the basic prototype of the building structure of the Hani mushroom houses was extracted for structural modeling. Finally, the structure of the prototype of the mushroom houses under different load conditions was analyzed. The results show that the Hani mushroom house design has a simple structure and good stability, can adapt to the local natural environment, and is the product of the Hani people's adaptation to the local natural environment. [ABSTRACT FROM AUTHOR]

A numerical analysis of part of the underground quarry of dimension stone with designed maximum dimensions of the rooms was carried out with the SAP2000 software based on the finite element method. The main objective of the analysis was to examine the preliminary stability and the influence of excavation on the redistribution of stresses in the surrounding rock masses, thus confirming the applicability of the tributary area method. The analytical solution with the tributary area method showed satisfactory agreement with the numerical calculations, and the results of the analytical calculations were on the safe side. The obtained results confirmed the predicted behaviour of the rock mass, which confirms the use of SAP2000 as a general-purpose software for civil engineering in the field of mining. The highest concentrations of stresses and strains are found in the edge areas of the pillars, so their correct design is crucial. The safety factor of the point with the highest stresses was determined and a value of 2.21 was obtained, thus fulfilling the stability condition. As for the influence on the surrounding area, stress changes of less than 10% were determined based on the solutions for the vertical stresses at a distance of 20 m from the underground excavation.

Copyright of Rudarsko-Geolosko-Naftni Zbornik is the property of Faculty of Mining, Geology & Petroleum Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The economic perception of earthquake resistance construction for medium- to high-rise RCC buildings is examined in this paper. The conventional way of creating high-rise buildings is not financially viable without a shear wall to withstand seismic energy. Framed structures with irregular floor plans that vary in size, shape, and geometry are also expensive. Many studies have been conducted recently on the Coupling Ratio (CR). The current analysis investigates the behavior of the coupled shear wall and the CR for an affordable earthquake resistance construction including the shear wall within a range of 30 % to 45 %. The study shows that shear walls could be reduced at 40–50 % and at 60–70 % of the base height for regular and irregular buildings, respectively. The current study also comes to the conclusion that coupled shear wall earthquake-resistant construction is more practical than the conventional approach because couple beams can be repaired with ease. [ABSTRACT FROM AUTHOR]

Many global structures, not initially designed to endure seismic forces, necessitate seismic strengthening. Existing research has explored diverse strengthening methodologies and assessed the seismic performance of these solutions. In the present study, a comparative analysis of a structure's seismic behavior before and after strengthening the building's columns was conducted using nonlinear time-history analysis. Two reinforcing techniques, Textile Reinforced Mortar (TRM) and Carbon Fiber Reinforced Polymer (CFRP) jacketing, were applied to a reinforced concrete building. Both techniques aimed to achieve full composite action (full bond) between the jacketing material and the existing concrete columns. The SAP2000 software was employed, strictly adhering to the Federal Emergency Management Agency (FEMA) 356 specifications for beams and column hinges. The analysis treated beam and column elements as nonlinear frame components, defining plastic hinges at their respective ends to simulate their behavior. Specifically, the beams were modeled to only possess moment (M3) fiber hinges, while columns were designed to accommodate axial load and biaxial moment (PMM) fiber hinges. The numerical findings indicated an average increase of 8% and 5% in base shear for buildings strengthened with CFRP and TRM jackets, respectively, when compared to non-strengthened buildings. Maximum story displacement increased by 9% and 4% correspondingly when the building was enhanced with CFRP and TRM jackets, compared to the original structure. It is noteworthy that both methods required a similar number of columns to be strengthened, yet the total cost of CFRP was found to be approximately 35% higher than that of TRM. [ABSTRACT FROM AUTHOR]

The design of multiple degrees-of-freedom frames is critical in civil engineering, as these structures are commonly used in various applications such as buildings, bridges, and industrial structures. In this study, a six-degrees-of-freedom beam-column element stiffness matrix was formulated by superposition of beam and truss elements stiffness matrices and was adapted to statically analyze indeterminate frame structures. The development of a numerical model for the frame structures was achieved using the finite element method in the current study. Also, the investigation of the effects of various parameters such as frame geometries, material properties, and loading conditions was conducted on the internal forces developed in the frame structures. Three different parametric study cases that presented the frame structures with varying geometries and loading conditions were analyzed utilizing this matrix approach for the sake of emphasis and to evaluate the flexibility and adequacy of this formula to analyze the indeterminate frames using the MATLAB software. The analysis method comprised the derivation of the system displacements employing the relationships between the stiffness matrix and fixed end forces as the force vector and taking the attained displacements, which would be transformed to the local coordinates to obtain the member forces. The computed results from the element stiffness matrix approach were further statistically compared with the results achieved from the finite element software (SAP2000) applying the analysis of variance (ANOVA). The statistical results showed a P-value > 0.05, which indicated a good correlation between the compared results and adequate performance for the derived beam-column element matrix formula method. [ABSTRACT FROM AUTHOR]

A reinforced concrete structure design is carried out based on structural analysis results. From this, the engineer defines the most appropriate design technique for each type of building. Due to the importance of structural analysis, this paper proposed to carry out the analysis, dimensioning, and detailing of a floor of massive slabs, through three distinct methodologies, consisting of an elastic analysis, based on the Theory of Grids for deformable supports, a plastic analysis based on the Theory of Rupture Lines, and a numerical analysis by the Finite Element Method (FEM), carried out using the SAP2000 software. The accomplishment of this research had as its main objective to evaluate the steel consumption demanded by each analysis methodology used, and to establish a comparative study about the soliciting efforts determined by the three methods of structural analysis. Thus, when analyzing the results, there were large discrepancies between the bending moments presented in each analysis methodology. Also, regarding steel consumption, there were considerable savings for the plastic model compared to the elastic model, and taking the numerical model as a parameter, an 11.52% higher steel consumption was observed for the elastic calculation.

This paper presents a combined method based on optimized neural networks and optimization algorithms to solve structural optimization problems. The main idea is to utilize an optimized artificial neural network (OANN) as a surrogate model to reduce the number of computations for structural analysis. First, the OANN is trained appropriately. Subsequently, the main optimization problem is solved using the OANN and a population-based algorithm. The algorithms considered in this step are the arithmetic optimization algorithm (AOA) and genetic algorithm (GA). Finally, the abovementioned problem is solved using the optimal point obtained from the previous step and the pattern search (PS) algorithm. To evaluate the performance of the proposed method, two numerical examples are considered. In the first example, the performance of two algorithms, OANN + AOA + PS and OANN + GA + PS, is investigated. Using the GA reduces the elapsed time by approximately 50% compared with using the AOA. Results show that both the OANN + GA + PS and OANN + AOA + PS algorithms perform well in solving structural optimization problems and achieve the same optimal design. However, the OANN + GA + PS algorithm requires significantly fewer function evaluations to achieve the same accuracy as the OANN + AOA + PS algorithm. [ABSTRACT FROM AUTHOR]

In the Second World Conference on Disaster Risk Reduction (WCDRR) the concept of resilience has been presented as an Effective Strategy to improve post-earthquake conditions. One of the principles of resilience is “quick response”, which requires having relevant information to determine the level of vulnerability of the city. For this purpose, many studies have been done in recent years to investigate the seismic behavior of a variety of infrastructures in a city. The fragility curve is one of the most popular tools among researchers to investigate the probabilistic seismic behavior of structures. It expresses the degree of structural vulnerability by indicating the exceedance probability of damage versus the given level of ground shaking. In this study, 24 fragility curves are developed for four typical intermediate Reinforced Concrete Moment Resistant Frame structures in Qods town (located in Qom, Iran) with two number of stories (4 and 8) and two number of bays (1 and 2). They are derived through nonlinear incremental dynamic analysis in one and two horizontal directions under two sets of near-field and far-field ground motion records. The results indicate that the seismic response of structures is the same for uni-directional and bi-directional analyses. Also, it seems that the response of the structures with periods greater than 1 sec is in correlation with the mass-to-stiffness ratio. Change in the width and number of bays of the structure does not affect the probability of failure, as far as the width to the number of bays ratio remains constant. Furthermore, the probability of failure is higher when the structure is subjected to near-field earthquake ground motion records.

This paper presents a study on the modelling approaches for column loss scenarios using software that is widely available to structural engineers worldwide, with the goal of providing practical guidance to designers faced with the need or the opportunity to perform progressive collapse analyses. The presented study leverages recent experimental results on column removal in a composite frame obtained at the University of Trento. Comparisons between experimental data, results of high‐definition finite element analyses, and the simulation results obtained using commercially available software are performed and conclusions are drawn based on the modelling approach used. Furthermore, a parametric study on various column loss scenarios in a prototype building is conducted and the results are compared with highdefinition model results in literature. It is concluded that the proposed modelling approach can be successfully used in practical cases, with results that are quite satisfactory both at the local and at the global level. [ABSTRACT FROM AUTHOR]