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Before reassessing the reliability condition of an offshore jacket platform, it is essential to understand the behaviours that the offshore platform exhibits while it is at sea. This paper presents the response of the offshore jacket platform as its ultimate strength under operating and extreme loads. Malaysian waters' metocean data from a 1-year return period (operating condition) and a 100-year return period (storm condition) are used to predict the four-legs jacket platform's behaviour by evaluating its ultimate strength. Also, two values of minimum design water depth (WD) of 105.9 m and maximum design WD of 115.4 m are chosen. The SACS software, a nonlinear finite element analysis software, is used to calculate the jacket platform's ultimate strength, called pushover analysis. For instance, the pushover analysis result will determine the Reserve Strength Ratio (RSR) as an approach to examining the offshore jacket platform's ultimate strength. Responses to the offshore jacket platform are base shear design, base shear ultimate, rotation, displacement, and moment, which illustrate the behaviour of the offshore jacket platform. There are eight combinations of environmental load directions are applied, to obtain the structure's weakest part. It is found that 45° is the critical direction for maximum design WD, while 90° is the critical direction for minimum design WD. The study's findings indicate that the response of the offshore jacket platform is very important for the safe design and operation of offshore jacket platforms. [ABSTRACT FROM AUTHOR]

Ductility deficiency in reinforced concrete (RC) piers is a substantial factor contributing to earthquake damage in bridge structures. In this study, the conventional concrete in the potential plastic hinge area was substituted with polypropylene fiber-reinforced engineered cementitious composite (PP-ECC), thereby leveraging its high ductility characteristics to explore the seismic performance of RC piers strengthened by PP-ECC. A finite element model was established to discuss the reinforced height, axial compression ratio, longitudinal reinforcement ratio and stirrup ratio on the hysteresis performance by referring to a published paper with a 1/5 scale test specimen. Based on the results of the parameter analysis, an ideal set of configuration parameters was proposed. Subsequently, a full-size simplified mechanical model was established with ideal reinforcement parameters. Time-history and pushover analysis were utilized to test the seismic response. The study indicates that the two analytical methods were largely consistent. The improvement in the displacement and shear force of the strengthened pier gradually decreased with the increase in acceleration amplitude. Time-history analysis reveals a decrease in the enhancement of displacement from 82.26% to 17.98% and a reduction at the bottom reaction from 12.2% to 1.5%. Under the pushover analysis method, the retrofitting level of the top displacement decreased from 77.22% to 11.53%, whereas the improvement level of the bottom shear decreased from 9.62% to 3.69%. These results provide a theoretical basis and reference standard for the application of PP-ECC. [ABSTRACT FROM AUTHOR]

The building industry requires the development of a ductile lateral force resisting system made of mass timber to help mass timber to continue to grow in popularity as the primary structural building material. The OpenSees framework was used to develop a numerical model of a single-story timber frame with a timber buckling-restrained brace, which was validated by the results of a previously completed series of quasistatic cyclic timber buckling-restrained brace (TBRB) component and subassembly tests. The experimental validation included a model developed for the hysteretic behavior of the TBRB and the rotational capacity of beam–column joints made with mass ply lam (MPL) panels, two slotted-in steel plates, and a number of steel dowels. The single-story model TBRB braced frame was then expanded to a numerical model of an eight-story mass timber buckling-restrained braced frame. The TBRB frame was analyzed with static pushover, quasistatic cyclic loads, and earthquake simulations. During the simulation of eleven design-level earthquake ground motions, the building experienced a peak interstory drift at of 2.54% at the first-floor level and a peak floor acceleration of 1.7g at the roof. The numerical model developed in this research of a timber buckling-restrained braced frame with TBRBs is novel and could be used to design timber buckling-restrained braced frames as a ductile lateral force resisting solution for mass timber buildings in seismic regions. [ABSTRACT FROM AUTHOR]

Masonry towers are peculiar structures with complex structural behavior despite biased conclusions deriving from their geometrical regularity and simplicity. Their geometrical features and the epistemic uncertainty that masonry material bears strongly influence their static and seismic behavior. This paper investigates a remarkable and representative case study. The bell tower of Portogruaro (Italy) is a 57 m high tall construction, built in the XII-th century, and has a notable inclination. The Italian Guideline for the safety assessment of masonry towers is a key focus in this paper, highlighting the pros and cons of different suggested approaches. Some relevant proposals are presented in this paper in order to address the seismic safety assessment of masonry bell towers. The findings show that very slender structures do not meet the guidelines recommendations due to limitations in their current stress state. In addition, in similar cases, the recommended values for the mechanical properties of masonry material led to predicting non-withstanding structural behavior, questioning the correct choice of the adapted material properties. Advanced pushover analysis has been conducted in order to investigate the results of the simplified approach in terms of failure patterns and seismic safety estimation. The simulations are implemented for four different hypothetical scenarios of the existing masonry mechanical properties. The results obtained for the case study tower reflect a different perspective in the seismic assessment of masonry towers when specific approaches are defined. The preliminary results on the safety of Portogruaro Tower show a significant variability of seismic safety based on the adopted scenario, highlighting the necessity to pay attention to the preservation state of the present case and of similar ones. [ABSTRACT FROM AUTHOR]

This work presents the findings of a series of studies conducted on of the temple Nuestra Señora de la Merced, located in The Historic Center of the city of Puebla, Mexico. The temple is a colonial building with heritage value that has undergone structural modifications and suffered damage from overloading generated by earthquakes and bombings. A noteworthy earthquake is the one of October 2, 1864, which severely damaged the second level of the tower. The earthquake of September 19, 2017, caused cracking and fissures in some elements of the structure, such as the keystone of the choir arch, where a plastic joint was formed. The arch was modeled in Sap 2000 v20 to perform a Pushover analysis; ambient vibration, temperature, and humidity were recovered, variables that cause degradation of materials. A topographic survey of the façade and a photogrammetric study of the entire structure's exterior were conducted. [ABSTRACT FROM AUTHOR]

Alton Apartment is a high-rise residential building. The city of Semarang, within a radius of 500 km, has a fault range with a strength of up to 8.3 magnitude. The purpose of this study is to calculate the performance level of the structure, find out the nonlinear static procedure conditions and whether the analysis results can be used, calculate the value of ductility R, check the boundaries between levels, check the influence of P-delta, adjust horizontal irregularities, and check the vertical irregularity conditions. This study uses the FEMA 356 method. New regulations are used in the analysis, such as peak acceleration maps and response spectra from PuSGeN in 2021, deaggregation maps of Indonesian earthquake hazards for planning and evaluation of earthquake-resistant infrastructure from the Director General of Cipta Karya in 2022, and earthquake resilience planning procedures for building and non-building structures from SNI 1726-2019. The result of the structure performance of the drift value is below 1% for the life safety (LS) performance level on the 250-year earthquake map, and the result of the drift value is below 2% for the collapse prevention (CP) performance level on the 100-year earthquake map. The results of the FEMA 356 condition one analysis show that the strength ratio (μstrength) value of less than μmax has been met for 250-year and 1000-year earthquake maps with a review of the x and y directions of the earthquake. The value of the R ductility in 250-year and 1000-year earthquakes is above seven according to the earthquake force holding system of special reinforced concrete sliding walls. [ABSTRACT FROM AUTHOR]

Application of displacement based seismic design in light‐frame timber construction This contribution deals with a displacement based seismic design procedure in timber construction. After a short explanation of the calculation methods regulated by standards, two different models are described with which the non‐linear behaviour of bracing elements in timber construction can be predicted to be included in a displacement based seismic design. In addition to the proposal in the current draft of Eurocode 8, an own approach is presented. The models are compared for different configurations of light frame timber shear walls and the differences are shown. Subsequently, displacement based seismic design is carried out on a two‐storey and a four‐storey reference building, taking into account different design configurations of the bracing system. It can be shown that a displacement based seismic design behaves very robustly in relation to changes of the input parameters and that there is a high potential to quantify hidden potentials in terms of deformation capacity in a structure. [ABSTRACT FROM AUTHOR]

Loss assessment is becoming a more familiar instrument in the seismic performance assessment of existing structures. Different approaches exist with varying degrees of complexity. The most notable is the component-based approach implemented within the FEMA P-58 guidelines. Despite recent research developments, practitioners must be provided with tools to conduct building-specific loss assessments simply and accurately. A simplified alternative to computationally intense component-based loss assessment is via storey-loss functions (SLFs). They reduce computational effort by describing a building typology's expected repair costs directly as a function of structural demands typically available to engineers, circumventing many steps of damage state and repair cost estimation for each individual damageable element in the structure. This study presents a pushover-based approach to estimate economic losses intended for practical application. It is implemented within a previously defined framework for simplified pushover-based seismic risk estimation via seismic hazard and vulnerability approximations. This additional simplification of direct losses utilises SLFs with structural response parameters like peak storey drift and peak floor acceleration. The steps required to apply the proposed approach are demonstrated via a case study application to infilled reinforced concrete frame structures. The method's accuracy is appraised via a comparison with other simplified loss assessment methodologies currently available. It is seen that when taking the more rigorous component-based approach as a benchmark, the proposed approach exhibits excellent accuracy and robustness compared to existing methodologies of this sort, paving the way as a candidate to adopt in future codes and guidelines. [ABSTRACT FROM AUTHOR]

Reinforced concrete bridge piers are often subject to spatially non-uniform deterioration which typically produces strength and ductility degradation. When piers are subject to deterioration, the sectional response is no longer uniform and the determination of the pushover curves from sectional response is no longer immediate. This paper proposes a simplified procedure to accomplish this task for RC bridge cantilever piers. The method is simplified only with respect to geometric nonlinearities and yields an accurate estimate of the ultimate displacement, free of numerical issues typical of fiber-based finite elements. The procedure is based on an iterative approach to enforce the element equilibrium under P-Delta effects induced by vertical loads and can consider arbitrary deterioration patterns through the specification of different moment-curvature response along the elevation. After validating the approach with experimental results, a parametric analysis of the influence of sectional strength and ductility degradation is carried out for the case study of a rectangular hollow RC pier. Results show that significant variations of the pier equivalent plastic hinge length can be expected because of the occurrence of deterioration in the lower part of the pier. Moreover, paper provides quantitative measure of the extent of the strength and ductility degradation. [ABSTRACT FROM AUTHOR]

Masonry towers are peculiar structures with complex structural behavior despite biased conclusions deriving from their geometrical regularity and simplicity. Their geometrical features and the epistemic uncertainty that masonry material bears strongly influence their static and seismic behavior. This paper investigates a remarkable and representative case study. The bell tower of Portogruaro (Italy) is a 57 m high tall construction, built in the XII-th century, and has a notable inclination. The Italian Guideline for the safety assessment of masonry towers is a key focus in this paper, highlighting the pros and cons of different suggested approaches. Some relevant proposals are presented in this paper in order to address the seismic safety assessment of masonry bell towers. The findings show that very slender structures do not meet the guidelines recommendations due to limitations in their current stress state. In addition, in similar cases, the recommended values for the mechanical properties of masonry material led to predicting non-withstanding structural behavior, questioning the correct choice of the adapted material properties. Advanced pushover analysis has been conducted in order to investigate the results of the simplified approach in terms of failure patterns and seismic safety estimation. The simulations are implemented for four different hypothetical scenarios of the existing masonry mechanical properties. The results obtained for the case study tower reflect a different perspective in the seismic assessment of masonry towers when specific approaches are defined. The preliminary results on the safety of Portogruaro Tower show a significant variability of seismic safety based on the adopted scenario, highlighting the necessity to pay attention to the preservation state of the present case and of similar ones.

Following recent earthquakes, precast buildings exhibited a strong seismic vulnerability related to the presence of closure external panels. The aim of this work is to simulate the seismic response of existing single-storey precast buildings in the case of explicit modelling of external panels. The considered case studies are precast buildings representative of the Italian building stock in the 1970s and 1990s, characterised by two different cladding systems, namely, masonry infills and reinforced concrete precast panels, respectively. The explicit modelling of infills and panels, typically introduced solely as participating masses, provided insights into their actual contribution on the global structural behavior. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering 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.)

The complexity in nonlinear behavior of torsional-irregular buildings in combination with uncertainty due to the natural randomness of earthquake records has been always a main challenge for buildings' seismic design. To find a solution to this challenge, three reinforced concrete (RC) building archetypes were designed and next developed into their nonlinear models. Nonlinear static (pushover) analyses were performed to calculate the capacity of the archetype models in all principal and non-principal directions while incremental dynamic analyses (IDAs) were conducted by applying 30 accelerograms from both near-field and far-field earthquakes. The IDA capacity curves, collapse fragility curves and log-normal cumulative distribution functions (CDFs) were established by including both the aleatory randomness and epistemic uncertainty. Despite previous studies wherein fragility curves were given by evaluating structures' collapse along structural reference axes or simply on x , y -axes, in this paper, possible building collapse on a critical non-principal direction (where maximum seismic response was observed) was simulated and its probability was accounted for developing IDA curves and log-normal CDFs. Accordingly, this issue was mirrored in computing available/acceptable collapse margin ratios (CMRs). In addition to the well-known outline used for calculating CMRs in the literature (that is based on estimation of collapse capacity in terms of earthquake intensity measure (IM)), the framework proposed here includes a new method for calculating the CMRs in terms of displacement-based drift, ductility, and damage. The superiority of the proposed method over the former is consistent with the buildings' design procedure that is governed by storey drift control rather than base-shear strength. Refined statistics of CMRs given by taking into account displacement-based responses illustrate the available CMRs exceed the acceptable CMRs, meaning that a satisfactory safety margin against collapse will be anticipated in the targeted building class if a suitable yielding mechanism with sufficient ductility is provided for seismic force-resisting system by applying seismic design provisions of the current codes. [ABSTRACT FROM AUTHOR]

Compliance with the "strong column - weak beam" criterion in the structural design of buildings ensures better behaviour of structures in seismic events. Design standards recommend an over-resistance factor of between 1.2 and 1.4. The consideration of the Dynamic Soil-Structure Interaction DSI in the analysis modifies the collapse mechanism, so researchers recommend factors higher than 2. In the present research a nonlinear static analysis (pushover) is developed, using ETABS V19 software, of a 12-story reinforced concrete building with mixed typology, in which stiffness ratio values of 1.4, 2, 3 and 4 are used, and the influence of this parameter on the structural response of the building is determined. The IDSE is considered in the analysis using Sargsian's formulations. It is concluded that the increase of the stiffness ratio influences the collapse mechanism of the structures. [ABSTRACT FROM AUTHOR]

The steel shear wall has been introduced as a system with high stiffness and strength and a considerable capability in absorbing seismic energy. Due to its special advantages compared to other lateral load-resistant systems, this system is being used in tall buildings more and more frequently. Ductility and energy absorption are important parameters to be considered when choosing a robust lateral load-resistant system. By increasing the ductility and energy absorption of the structures, their seismic performance and safety are improved. Ideally, a structural system should provide both ductility and energy absorption in an economic way. This study presents the numerical simulation of the seismic behavior of a recently developed four-layer steel shear wall composed of corrugated and flat sheets. The simulations were performed using finite element software ABAQUS. Nonlinear static analysis was used to derive seismic parameters. The results showed that the corrugated sheets surrounded by flat sheets provide greater seismic parameters such as ductility and over-strength compared to double corrugated walls. According to the results, the calculated R-factor, displacement amplification factor, and the overstrength factor of the proposed wall were 4.58, 8.21, and 1.26, respectively. Furthermore, to use the seismic parameters of the shear wall, some relationships have been presented for incremental strength and stiffness coefficients without the need for finite element modeling. Compared to the finite element results, the presented relations had good accuracy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Railway Science & Engineering is the property of Journal of Railway Science & Engineering 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.)

The present paper analyses some possibilities to improve the provisions concerning the seismic design of diagonal braced frames according to the in charge European and Romanian seismic design code (EN 1998‐1:2004 [1], respectively P100‐1/2013 [2]). Three design variants were used for the dimensioning under seismic actions of two ten story concentrically braced frames, taking into consideration different contributions of the tensioned and compressed braces in carrying horizontal seismic forces. The considered braced frames had two spans of 6.0m and ten storey of 3.5m. One of the frames had ascendant diagonal braces (from the lateral columns to the central column) and the other had descendant diagonal bracings (from the lateral columns to the central column). Static nonlinear analyses were performed with all the designed variants of the frames. The loading and deformation states at different steps during the analyses were compared. The distribution of plastic hinges in the structure was analysed. A more favourable behaviour of the frame during static nonlinear analysis was ensured by providing reduced cross‐sections along all frame girders ends (resembling the dog‐bone detail). [ABSTRACT FROM AUTHOR]

The methods of nonlinear analysis allow a better structural design and more accurate answers in the verification of a structure, through which it is based on the linear analysis of the educational institution Héctor Rene Lanegra Romero; this has a current systemic structural configuration 780, which has been designed under the parameters of the E.030 standard. To know, verify and analyze the structural performance in which the educational institution is located, nonlinear static analysis was used; which consists of a Pushover analysis. The Pushover analysis allows us to calculate the seismic actions in structures where the elastic behavior of each element is observed, it also allows us to see the operational seismic performance in which the educational institution is located, through which capacity curves are obtained, generation of plastic ball joints and the verification of the point of performance of the building; which allows identifying if the said structure is active for a seismic signal. [ABSTRACT FROM AUTHOR]

Any public infrastructure has a set service life limit. In the Indonesian case, the public building has a 50-year design life. This paper presents a performance assessment of a multiple-story building in Aceh-Indonesia. A multi-story Faculty of Engineering Universitas Syiah Kuala building was used in this study. This multi-story building structure has been used for more than 24 years since it was built in 1998. This structure is 29.4 m long, 13 m wide, and 14.4 m tall in geometric terms. This study reveals how this three-story building behaves, including displacement, base shear, and structure performance level per ASCE 41-17 criteria. The processes in this study are broken down into various stages, including pushover analysis and comparing the building's current natural frequency. ETABS software was used to model building structures. According to the study, the building's performance is still more or less similar to the initial plan. Pushover in the X-direction (Push X) is believed to be immediate occupancy (IO), and pushover in the Y-direction (Push Y) is believed to be life safety (LS). The pushover analysis results for Push X suggested that the structure is safe and retains rigidity. Push Y indicated minor damage within the life safety category after a service life of 24 years. This pushover analysis indicated that the structure has reduced its rigidity, making it less able to resist further displacement. Based on the base shear, which experiences a displacement that is significantly greater than the estimate at the original planning stage, it is known that stiffness decreases. [ABSTRACT FROM AUTHOR]

El análisis no lineal estático, denominado Pushover, consiste en la aplicación de fuerzas laterales incrementales a una estructura para visualizar su probable desempeño ante acciones sísmicas, esto es importante en países como Ecuador donde se tiene una alta sismicidad. En este artículo, se describen las nuevas funciones de CEINCI LAB para el análisis Pushover de pórticos de acero. El Sistema Computacional CEINCI LAB es una colección de funciones para el análisis sísmico-estructural. Desde el año 2019, se han desarrollado funciones para facilitar el ingreso de datos y la presentación de resultados en los análisis no lineales de estructuras empleando OpenSees. Nuestra motivación es presentar nuevas funciones que permitan obtener animaciones del análisis y apreciar el nivel de daño en los elementos estructurales mediante un código de colores, facilitando la interpretación de los resultados. Además, mediante estas funciones se genera un archivo editable con la información del modelo estructural, tipo de análisis, resultados y otros parámetros de interés que pueden ser modificados bajo demanda. Se ilustra el procedimiento de modelado, con énfasis en las funciones computacionales desarrolladas y su funcionalidad

The direct modeling of masonry infill walls on many buildings, based on damage recorded by various past earthquakes, has become increasingly necessary in order to identify the seismic behavior of these elements, which constitute an important part of reinforced concrete buildings. In this paper, several 3D models were analyzed by the nonlinear static (pushover) method, when ignoring, and when considering, masonry infill walls. The finite element software SAP analyzed the proposed models. These models represent low and mid-rise reinforced concrete buildings infilled with double-leaf hollow bricks. The properties of materials used in Algeria, either in the frame elements or the infill elements, were used. The results obtained were compared according to two parameters, the natural time period of the building and the pushover curve, by varying the values of the dead load and the concrete compressive strength. The results were discussed according to the suggested parameters. The results showed that indirect modeling of such walls, either by taking assumptions embedded in the seismic behavior factor or by means of the macro-modal, can lead to a poor appreciation of the seismic behavior of such buildings. Consequently, direct modeling of walls by the infill of the real void showed acceptable results to some extent. This contributes greatly towards understanding the seismic behavior of this type of building. [ABSTRACT FROM AUTHOR]

Buildings’ responses to lateral forces have been the topic of a great deal of research work in recent years. Performing a comprehensive nonlinear analysis is required for Performance-Based Design. During earthquakes, nonlinear static analysis (pushover analysis) is frequently employed in performance-based design, where gravity loads are held constant and lateral forces are increased monotonically until the target displacement is reached. The capacity curve, derived from a pushover analysis, depicts the overall performance of the structure by illustrating the relationship between the base shear and the roof displacement. There has been a lot of research on structures with shear walls, but none of it has focused on finding the best possible spot. As part of these analyses, shear walls are placed at different locations of the structure. We analyzed 13 different models to determine the best location, and found out that model 6 performing well, when comparing with other models. As a result, PO-Fig. 7 is found out to be subjected to 76.89% greater shear resistance capacity than the no-shear-wall model. [ABSTRACT FROM AUTHOR]

In recent years, several earthquakes have drawn the attention of researchers to the effectiveness of antiseismic devices (AD) and structural designs. These elements certainly influence building safety, but they also impact the environment. Hence, the overall ecological footprint of a building is varied by the size of the structural elements and the inventory of construction materials used. Since both parameters (safety and environmental footprint) are currently key factors in the building sector, this paper aims to compare the ecological impact produced for each of the three most common antiseismic devices: chevron braces, shear walls and energy dissipators. For such a purpose, a 15-storey building was modelled whose structure was sized by setting a similar base shear capacity (i.e. approx. 2500 kN), regardless of the incorporated antiseismic device. Besides this, with the aim of determining the influence of reinforcement ratios, three different ratios (from 3 to 8%) were chosen for each case. Thus, four different structures (including a bare frame as a control case) were assessed in terms of the mechanical response (i.e. modal parameters, pushover curves and time history analysis) and environmental impact (i.e. life cycle impact assessment method). The results showed that the use of energy dissipators provides the most satisfactory mechanical performance and leads to minimise both ecosystem quality and resource scarcity. Although the use of shear walls certainly shows the lowest impact on the human health category, dynamic calculations demonstrate that this solution greatly increases the rigidity, which hinders the effectiveness of such antiseismic devices. The results provide comprehensive guidance for building designers, showing the main advantages of each AD, in terms of safety, damage control and environmental impact. [ABSTRACT FROM AUTHOR]

Buckling-restrained braces (BRBs) have proven to be a valuable earthquake resisting system. They demonstrated substantial ability in providing structures with ductility and energy dissipation. However, they are prone to exhibit large residual deformations after earthquake loading because of their low post-yield stiffnesses. In this study, the seismic response of RC frames equipped with BRBs has been investigated. The focus of this research work is on evaluating the effect of the BRB yielding-core length on both the maximum and the residual lateral deformations of the braced RC frames. This is achieved by performing inelastic static pushover and dynamic time-history analyses on three- and nine-story X-braced RC frames having yielding-core length ratios of 25%, 50%, and 75% of the total brace length. The effects of the yielding-core length on both the maximum and the residual lateral deformations of the braced RC frames have been evaluated. Also, the safety of the short-yielding-core BRBs against fracture failures has been checked. An empirical equation has been derived for estimating the critical length of the BRB yielding cores. The results indicated that the high strain hardening capability of reduced length yielding-cores improves the post-yield stiffness and consequently reduces the maximum and residual drifts of the braced RC frames.

Pasar Raya Padang Market blok IV was built in 2016 as an resisting earthquake building based on SNI-1726-2012. The building has a building dilatation with a distance of 1 cm. The purpose of this study was to evaluate the dilatation distance of the Raya Padang Blok IV market building based on the seismic forces required in SNI-1726-2019.The evaluation method used in this research is numerical analysis method by using non-linier pushover over analysis. The numerical model used 3D model with the input material and the earthquake loading according to the proposed design and the response spctrum from SNI-1726-2019. This research evaluate overall structural performance of the buildings based on ATC-40. The results of the pushover analysis of the Raya Padang Blok IV Market building are the maximum displacement of the building of 9.936 mm, the allowable displacement is 320 mm, and the shear force to occur is 1409.094 KN, while the design shear force is 1508.3265. The results of this analysis conclude that the existing dilatation distance in the existing building meet the minimum requirement need based on this study. Building performance level reachs Immidiate Occupancy Level which means the building can be functioned immideately as the eartquake ends.

Indonesia, which has tectonic conditions in the form of a large meeting point of the world's plates and several small plates, makes the region in Indonesia the center of earthquake occurrences and earthquake-resistant buildings are an absolute necessity. Eccentrically Braced Frames (EBFs) are a model of earthquake-resistant steel building structures that can limit inelastic behavior only to link elements, where the use of these links, especially replaceable links, can facilitate post-earthquake building repairs without having to reconstruct the main building. This study will analyze the stability, behavior, performance levels, and energy dissipation capabilities of six EBF models by combining vertical link and horizontal link configurations for different building height classifications, namely low, medium, and high buildings. Analysis uses the Response Spectrum Analysis and Pushover Analysis methods with the help of structural analysis software. From this analysis, 3-storey H-EBF has the highest stability, 10-storey V-EBF has the fastest time to reach the first yielding condition and consumes the most energy, 3-storey V-EBF has the highest ductility, and 3-storey H-EBF has the highest stiffness. highest. However, the performance level of all EBFs is in the form of Immediate Occupation and similar collapse mechanisms.

The evaluation of seismic risk in structures requires information on both site hazard and structural vulnerability. Hazard can be quantified via probabilistic seismic hazard analysis, while seismic vulnerability can be quantified using structural analysis; the former is typically specified via predefined national hazard models, whereas the latter is more structure-specific and can be computationally expensive depending on the numerical modelling and analysis procedure complexity. As a compromise, various simplified seismic response evaluation methods have emerged and been implemented in assessment codes and guidelines (e.g., N2 method in Eurocode 8, SPO2IDA in FEMA P695). Furthermore, the seismic assessment and rehabilitation of existing structures have seen the introduction of risk classification guidelines. These are tools to primarily assist practitioners and decision-makers in understanding and managing seismic risk and the possible implications of different retrofitting schemes. Risk classification guidelines typically use loading-based quantities such as the seismic capacity-to-demand ratio. However, several drawbacks are associated with adopting loading-based quantities, namely the lack of uniformity of the actual seismic risk, expressed as a mean annual frequency of limit state exceedance. To address these drawbacks, this paper outlines a relatively simple pushover-based methodology for the direct evaluation of seismic risk (PB-Risk) for non-ductile infilled frame structures. The article describes a step-by-step framework for the simplified characterisation of hazard, vulnerability and subsequently seismic risk. It is quick and easy to implement within a practical and code-based setting and can be adopted within risk classification guidelines. The application of the proposed PB-Risk methodology is demonstrated via several case study applications, and its robustness in characterising seismic risk with respect to other simplified non-linear static formulations for infilled frame buildings is shown. [ABSTRACT FROM AUTHOR]

The present paper investigates the effect of the harmfulness of a potential earthquake on structural and seismic risks. It takes into account the magnitude, epicentral distance, and pseudo depth at the hypocenter as well as the soil classification in order to generate synthetic seismic motions to be considered as signal inputs for a structural seismic analysis. The most typical typology of dwellings and buildings that are widely existing in Algeria, i.e., a reinforced concrete frame structure, is considered for the case study. The results show that the theoretical models developed in this study are able to predict the performance point (spectral displacement) according to the cumulative absolute velocity. They also show that(CAV-Sd) (Sd being the spectral displacement of the performance point defined by a pushover analysis) is slightly influenced by the value of the ultimate displacements of the structures and the soil parameters (shear velocity Vs).

Seismic bearings have been used to mitigate the harmful effect of the earthquakes. Torsion mode, one of the most important irregularities, generally increases the shear forces to the vertical members such as columns and shear walls in turn this may results in brittle failure of the reinforced concrete (RC) members. Accordingly, it is vital to eliminate the torsion failure mode or switch to the higher modes with lower mass contribution. This study has evaluated the seismic performance of a high-rise building with torsion mode through push-over analysis including nonlinear time history analyses. The damage conditions of RC structural members are defined considering the Eurocode definitions and general performance assessments of the building have been evaluated accordingly. Lead rubber bearings have been used for base isolation system. By using enough number of rubber bearings, the dominant torsion mode (first free vibration mode) has been shifted to higher modes. Various earthquake records have been used in non-linear dynamic analysis to evaluate the positive effects of the bearings. The results revealed that proper arrangement of rubber bearings in structural plan of ground floor can effectively improve dynamic behavior of a high rise building with torsional instability to achieve better seismic performance. [ABSTRACT FROM AUTHOR]

Following the Zagreb earthquake in March of 2020, a destructive 6.2 magnitude earthquake struck Croatia again in December of 2020. The Sisak-Moslavina county suffered the most severe consequences; many historical and cultural buildings were badly damaged. In the education sector, 109 buildings were damaged. One such building is the case study of this research. The heritage-protected building of the First Primary School in Petrinja is an unreinforced masonry structure, constructed using traditional materials and building techniques. The historical background of the building and the results of the post-earthquake assessment are presented. A numerical calculation of three strengthening methods was performed in 3Muri software: FRCM, FRP, and shotcrete. Non-linear pushover analysis was performed for each model. Finally, the strengthening methods are compared based on the achieved earthquake capacity, cost, and environmental impact. [ABSTRACT FROM AUTHOR]

Data from past earthquakes is an important tool to reveal the impact of future earthquakes on engineering structures, especially in earthquake-prone regions. These data are important indicators for revealing the seismic loading effects that structures will be exposed to in future earthquakes. Five different earthquakes from six countries with high seismic risk were selected and were within the scope of this study. The measured peak ground acceleration (PGA) for each earthquake was compared with the suggested PGA for the respective region. Structural analyzes were performed for a reinforced-concrete (RC) building model with four different variables, including the number of storeys, local soil types, building importance class and concrete class. Target displacements specified in the Eurocode-8 were obtained for both the suggested and measured PGA values for each earthquake. The main goal of this study is to reveal whether the proposed and measured PGA values are adequately represented in different countries. We tried to reveal whether the seismic risk was taken into account at a sufficient level. In addition, target displacements have been obtained separately in order to demonstrate whether the measured and suggested PGA values for these countries are adequately represented in structural analysis and evaluations. It was concluded that both seismic risk and target displacements were adequately represented for some earthquakes, while not adequately represented for others. Comments were made about the existing building stock of the countries considering the obtained results. [ABSTRACT FROM AUTHOR]