Seismic Zone Research Articles

The Use of Externally Bonded Fibre Reinforced Polymer Composites to Enhance the Seismic Resilience of Single Shear Walls: A Nonlinear Time History Assessment

In medium- to high-rise buildings, single shear walls (SSWs) are often used to resist lateral force due to wind and earthquakes. They are designed to dissipate seismic energy mainly through plastic hinge zones at the base. However, they often display large post-earthquake deformations that can give rise to many economic and safety concerns within buildings. Hence, the primary objective of this research study is to minimize residual deformations in existing SSWs located in the Western and Eastern seismic zones of Canada, thereby enhancing their resilience and self-centering capacity. To that end, four SSWs of 20 and 15 stories, located in Vancouver and Montreal, were meticulously designed and detailed per the latest Canadian standards and codes. The study assessed the impact of three innovative strengthening schemes on the seismic response of these SSWs through 2D nonlinear time history (NLTH) analysis. All three strengthening schemes involved the application of Externally Bonded Fiber Reinforced Polymer (EB-FRP) to the shear walls. Accordingly, a total of 208 NLTH analyses were conducted to assess the effectiveness of all strengthening configurations. The findings unveiled that the most efficient technique for reducing residual drift in SSWs involved applying three layers of vertical FRP sheets to the extreme edges of the wall, full FRP wrapping the walls, and full FRP wrapping of the plastic hinge zone. Nevertheless, it is noteworthy that implementing these strengthening schemes may lead to an increase in bending moment and base shear force demands within the walls.

Earthquake-Resistant and Environmental Advantages of DIAGRID Systems in High Seismicity Zones

A comparison of the seismic response and environmental impact potential of two building systems is presented. Both buildings have 24 floors and a total height of 114 m, and are located in the Lake Zone of Mexico City. The first building, denominated traditional, uses composite (steel and reinforced concrete) moment-resisting frames and concentric diagonals. The second one, denominated innovative, is structured with steel perimetral diagonal grids and steel frames. Despite its lower weight, and smaller lateral strength and stiffness, the innovative system exhibits a superior seismic performance characterized by light damage on approximately 8% of its seismic-resistant elements for the design seismic excitation. In addition, the construction of the innovative system reduces emission of greenhouse gases by two thirds compared to its traditional counterpart. The example presented here provides an idea of the benefits that the use of innovative systems can bring to the Mexican design and building practices.

Women's experiences in the aftermath of the Kahramanmaraş earthquakes in Türkiye: A phenomenological study

This study aimed to understand women's experiences related to health problems and needs after the 2023 Kahramanmaraş earthquake, considered the “disaster of the century.” This study employed phenomenology, a qualitative research methodology, and used criterion sampling, a type of purposive sampling. The participants included women who had experienced both the major Kahramanmaraş earthquakes; whose houses were damaged in the earthquakes; who had to live in tents, cars, or other shelters; and who had been in the earthquake zone for about a month. Semi-structured interviews were used as a data collection tool to elicit women's thoughts and experiences after the earthquakes. The interviews were conducted face-to-face in a calm environment by taking the necessary precautions and recording the audio with the participants' written consent. The interviews lasted at least 25 min and at most 45 min. For evaluating the data, the researchers used descriptive and content analyses. After transcribing the voice recordings, the researchers created the code categories and themes. The study identified four themes: “burden of responsibility,” “security,” “care needs,” and “male dominance.” Using participants' statements directly in the findings increased the study's internal validity. The study's findings indicate that women continued to fulfill their social, childcare, and family care roles after the earthquakes. The findings suggest that during this period, women faced housing and security problems, their special needs were ignored, their needs were affected by male dominance, and they were subjected to physical and psychological violence.

AN INPUT-OUTPUT MODEL OF THE ECONOMIC STRUCTURE OF THE EARTHQUAKE AFFECTED REGION IN TÜRKİYE FOR EFFECTIVE AND EFFICIENT RECOVERY

Türkiye is frequently exposed to earthquakes due to its location in one of the most active earthquake zones in the world. Following the recent earthquakes in the southeastern part of the country, the need to quickly recover from the losses in the local and regional economies of the affected areas makes it extremely important to analyze economic structure to ensure a planned economic development. In view of this, this study aims to investigate the key economic sectors that should be prioritized for investment in the reconstruction process of these places for an effective and efficient economic recovery. In doing so, a static explicit Input-Output (I-O) Model based on Leontief's work is adopted. The key sectors that require investment priority for the recovery and development of local economies in the shortest possible time have been identified using a categorical classification methodology based on the unbalanced growth model proposed by Hirschman.

A Review Study on Belt Wall in Non-Regular Buildings in Various India Earthquake Zones

To reinforce a building's central walls and external columns and boost its stability against overturning, outriggers are robust horizontal frameworks like beams and frames. While cantilevers have been an attribute of buildings for more than fifty years, their performance has been enhanced by innovative design concepts. The structural system known as the foundation system is made up of horizontal cantilever portions that are fastened to the structure's external columns and interior core. The system's lateral stiffness and central moment arm are both enhanced by this link. By joining the core and the building supports, the stabilizer lowers the back moments inside the core and transfers moments from the core to the exterior supports. Steel, concrete, and composite materials are just a few of the elements that can be used to make stabilization systems. Usually the core is positioned on one side of the building and the stabilizers expand on the opposite side, or the stabilizers expand on one side of the central core. To stop lateral movement, the perimeter of the building is attached together and expanded by column-connecting walls. Wall-mounted stabilizers are more efficient than wall-free ones. The center wall cannot freely rotate on the external columns due to the stabilizing arm. The location of outriggers and tie rods, the quantity of outriggers, the form of the structure, the type of core (steel or concrete), and the height from floor to ceiling are just a few of the elements that might impact how well outriggers and straps function in the structure. Several studies were selected for this review study with the purpose of analyzing the impact of belt walls on irregular structures. Obtain a thorough analysis of the types of irregular buildings and how earthquakes affect these constructions. Earthquake zones are used in India to categorize the degree of seismic loading. Keywords: Belt Wall, earthquake zone, Irregularities of Building, Storey displacement, bending moment etc.

Analysis of multi-storey buildings with and without floating columns by using construction sequence analysis in different seismic zones in India

Analysis of multi-storey buildings with and without floating columns by using construction sequence analysis in different seismic zones in India

Experimental investigation on the origin of carbonaceous materials in the fault zone of the Wenchuan earthquake

Carbonaceous materials in seismic fault zones may considerably influence seismic fault slip; however, the formation mechanism of carbonaceous materials remains unclear. In this study, we proposed a novel hypothesis for the formation of carbonaceous materials in fault gouge. Thus, we conducted a CO2 hydrogenation experiment in a high-temperature reactor at a co-seismic temperature, with fault gouge formed during the Wenchuan earthquake as the catalyst. Our experimental results demonstrate that carbonaceous materials in fault zones are formed on the fault gouge during the chemical reaction process, suggesting that the carbonaceous materials are possibly generated from the catalytic hydrogenation of CO2, followed by thermal cracking of its products. The results of this study provide a theoretical basis for understanding fault behavior and earthquake physics.

A Review Study on Comparison of G+10 Structure with Several Materials Masonry, Concrete and Glass Fiber Reinforced Gypsum Panel (GFRG)

Glass fiber reinforced gypsum plasterboard (GFRG) is an environmentally friendly product. They are made of modified plaster and reinforced with fiberglass strips. Its main use is in the construction of walls, but it can also be used in combination with reinforced concrete on floors and roofs. The panels have voids that can be filled with concrete or reinforced with steel bars to increase strength and ductility. These panels can be used as an alternative building material to replace bricks and concrete blocks. IIT Madras has conducted several research studies and developed a structural design manual for designing buildings constructed by GFRG. Phosphor gypsum is a by-product of the fertilizer industry. In addition to its use as a fertilizer, building material, and soil stabilizer, approximately 85% of phosphor gypsum is disposed of near phosphate plants, which require large disposal sites. Phosphorus from gypsum can be effectively removed by creating glass fiber reinforced gypsum plasterboard (GFRG), also known as fast wall. They may or may not be used as support structures. In this research work we design three different models of G+10 in 5th zone of earthquake as on IS code. The lateral load such as earthquake is to be classified as live horizontal forces acting on the structure depending on the structure’s geographic location, height, shape and structural material. In this study, a multi-story Glass fiber reinforced panel and Brick-infill and concrete block infill wall building has been shown and performed by using software ETABS constructed on a plan ground having G+10 stories. Keywords: GFRG Panels, Concrete Blocks, Clay Bricks, Lateral Loading, Light weight Construction and Masonry etc.

Base Isolation and Energy Dissipating System in Earthquake Resistant Building Design

The utilization of base isolation is a crucial strategy for enhancing seismic resilience in structures. The method involves installing isolators and energy-absorbing devices beneath a building's superstructure to mitigate the destructive effects of earthquakes. When base isolation is implemented in a building, it not only makes the structure stronger and more stable, but also helps to safeguard lives and properties. This technique is particularly valuable for seismic retrofitting of historical buildings. In the present study, software called simulation of seismic isolation systems in structural analysis is employed, considering isolator characteristics, whether they exhibit nonlinear or equivalent linear behavior. Adhering to the IS 1893:2016 Code, the analysis utilized the SAP 2000 software package. A study was carried out to compare the effectiveness of base isolation systems versus fixed-base buildings in dealing with seismic activity. The study focused on analyzing various seismic indicators such as joint displacement, shear force, bending moment, building torsion, and the period of natural frequency. Results showed that models utilizing base isolation systems had significantly higher base shear values than those with a fixed-base building configuration. However, there was a significant 35% reduction in story shear values for the rubber isolation system and a 40% decrease for the friction pendulum model. Additionally, there was a 25% reduction in story drift for the rubber base model and a 30% decrease for the friction pendulum model. The friction pendulum model demonstrated the most effective control of these parameters across various seismic zone conditions. Key words: The topic of discussion pertains to Seismic Isolation with Rubber Bearing System and the Friction Pendulum Technique. Additionally, it includes SAP2000 Analysis, Story Drift Measurement, and Shear Force Evaluation in relation to these techniques.

Earthquake economic loss assessment of existing concrete shear wall residential buildings in Eastern Canada

AbstractPast major earthquakes have demonstrated that a significant proportion of existing residential buildings are vulnerable to seismic hazards, resulting in economic and social losses. The assessment of earthquake‐induced losses is crucial for devising strategies aimed at enhancing seismic resilience through mitigation plans and emergency response measures. This study intends to provide an analytical methodology for evaluating economic losses for existing residential concrete shear wall buildings in Eastern Canada seismic zones based on Canadian‐compatible seismic capacity parameters. A sampled data set related to residential buildings in Montreal was analyzed and statistical distributions were developed that represent the proportion of buildings in different seismic design code levels and number of stories. Vulnerability analyses were performed, which involved estimating buildings' response under seismic hazard inputs according to the 2020 National Building Code of Canada and conducting loss assessment for structural components, nonstructural displacement‐sensitive components, nonstructural acceleration‐sensitive components, and contents. The results of vulnerability analyses in terms of loss ratio curves showed that the seismic performance varies between mid‐rise and high‐rise concrete shear wall buildings with different seismic design code levels, and nonstructural displacement‐sensitive components exerted the most significant influence on overall economic losses among building components. In addition, a comparison was conducted between Canadian‐compatible economic loss ratio curves and those developed based on the standard seismic capacity parameters in the Hazus technical manual and differences in predicted loss ratios were discussed. The developed loss ratio curves can be integrated into regional scale loss assessment tools for rapid estimation of earthquake‐induced economic losses for concrete shear wall buildings as a function of seismic intensity.

Analysis of Road Traffic Accidents in Dense Cities: Geotech Transport and ArcGIS

Road Traffic Accidents (RTAs) provide a substantial risk to both public safety and infrastructure within severe earthquake zones. This research aims to provide a thorough analysis of the many elements that contribute to RTAs in the area. Although research on RTAs has been conducted in numerous settings, there is a lack of localized research specifically focused on developing countries. Therefore, this study is necessary to address this gap in literature. Our study focuses on examining the distinct issues and elements that are particular to this specific location. The objective is to provide customized solutions that effectively reduce the occurrence of accidents. The objective of this study is to examine the status of RTAs, ascertain the main factors contributing to RTAs, and provide viable approaches to improve road safety. A comprehensive study of data was undertaken, which included the examination of key highways, accident-prone areas, and causes contributing to accidents. Insights were derived by the use of statistical analysis, hotspot mapping, and the categorization of incidents. The results revealed a distressing roadway are afflicted by a significant frequency of accidents, even those occurring on prominent thoroughfares. Excessive speed has been revealed as the primary contributing factor, closely followed by negligence and recklessness. The common factor seen in these events was the insufficient enforcement of traffic regulations. The research highlights several practical consequences. Firstly, it is advised to implement urgent actions such as the upgrading of the traffic database, the adoption of contemporary traffic management software, and the enforcement of rigorous traffic laws. The establishment of a comprehensive centralized database system is crucial in order to enhance the documenting and management of accidents. Furthermore, the use of cost-benefit analysis provides justification for the adoption of traffic calming measures in locations with a high incidence of accidents. Furthermore, the implementation of continuous road safety awareness efforts and the establishment of clear legislative guidelines pertaining to fatal accidents are imperative measures in promoting enhanced road safety.

Assessment of RC Frame Structure under Different Seismic Condition

Abstract: Structures in seismic zones are especially prone to collapse during significant ground motion occurrences. This susceptibility is sometimes linked to flaws in seismic design principles, notably in the selection of suitable structural systems. Equivalent static analysis, which is often employed in seismic design, may not accurately account for the structure's strength and stiffness. As a result, ground floor columns may become highly reinforced, thereby lowering ductility, and causing poor performance. This thesis offers a parametric study of an RC frame structure developed for various seismic zones. The finite element software is used to model the structure to investigate performance levels. Pushover analysis was performed to determine the structure's seismic capacity and behavior under various seismic conditions. Parametric research employing RC Frames with demand variation was done to investigate the structure's behavior in different seismicity zones across the country

Optimization of Staging Height of RCC Overhead Water Tank in High Seismic Zones Using P-Delta Analysis

Abstract: This study investigates the P-delta effect, which is a secondary effect or a geometric non-linear effect in the analysis of a circular overhead water tank with a capacity of 100 KL using STAAD software in high seismic zones, i.e., Zone IV & Zone V with a focus on optimization of staging height and to quantify the effect of P-Delta. Initially, a linear static analysis was performed without considering the P-Delta effect to determine the shear forces, bending moments and lateral displacements due to all possible loads including seismic and wind loads acting on RCC overhead water tanks. Subsequently, the P-Delta effect has been considered to assess the structural behaviour of the RCC overhead water tank with varying staging heights. To optimize the staging height, the maximum lateral displacement has been considered as the governing criteria. Based on the analysis, the optimum staging heights can be observed at 30 m. and 33 m. in Seismic Zone V and Zone IV respectively

Investigation of the Impact of Different Earthquake Zones on Irregular Plan Buildings Managed by Belt Wall

Investigation of the Impact of Different Earthquake Zones on Irregular Plan Buildings Managed by Belt Wall

Influence of Farallon Slab Loading on Intraplate Stress and Seismicity in Eastern North America in the Presence of Pre‐Existing Weak Zones

AbstractDespite the stability of the continental interior, eastern North America has hosted many significant historical earthquakes. Seismicity concentrates within tectonically inherited structures, which can act as weak zones where stress accumulates. Within these zones, systematic stress rotations may be explained by long‐wavelength sources. We test the hypothesis that mantle‐flow driven by the Farallon slab contributes to intraplate seismicity via the reactivation of pre‐existing faults. We model the stress field using seismically constrained global high‐resolution finite‐element flow models with CitcomS. To isolate the slab's effect, we vary its buoyancy between a case of neutrality and a case with full negative thermal buoyancy derived from tomography. Low‐viscosity lithospheric weak zones located at failed rifts, loaded by a mass anomaly at depth, transmit elevated stresses to the overlying crust. The sinking of the Farallon slab drives localized mantle flow beneath the central‐eastern US, generating a large stress amplification of 100–150 MPa peaking over the New Madrid Seismic Zone (NMSZ). This stress amplification exerts a continent‐wide clockwise rotation on the stress field, which in the presence of weak zones reproduces some observed deviations of the seismically inferred SHmax from the regional borehole SHmax, bringing optimally oriented faults, closer to failure, some of which are associated with major historical earthquakes, including the Reelfoot Fault in the NMSZ and the Timiskaming Fault in Western Quebec. However, stronger lithospheric viscosity gradients, shallower weak zones, or weaker faults are still needed to fully reproduce the observed stress field in some areas.

Design and Analysis of General Hospital Building Using STAAD Pro

Abstract: Structural design is the primary aspect of the civil engineering. The foremost basic in structural engineering is the design of simple basic components and members of a building viz., Beams, Columns and Footings. The principal objective of this project is to analyze and design a general hospital using Staad pro. The design involves manual load calculations, analysis and design of the whole structure using STAAD Pro. The design methods used in STAAD-Pro analysis are Limit State Design conforming to Indian Standard Code of Practice. Structure considered for analysis and design is 21m high hospital building located in the seismic zone III. In this project, we study the effect of various load combinations on the structure by analysing the bending moment diagrams in post processing mode. The project involves detailed drawings of column layout, column detailing and beam detailing

Comparative Analysis of Framed-Tube & Braced-Tube System in Tall Buildings Using ETABS

Abstract: Since the rigid frame became popular in the first half of the 20th century, tall buildings with structural systems have evolved. The development of underlying frameworks for tall structures lays on reasonable realism, economy of material utilization, effortlessness and polish, and worry for constructability. We are now able to build buildings that are ever higher thanks to cutting-edge building materials, sophisticated computational software, and sturdy structural systems. The rationale behind the creation of structural systems for tall buildings is to achieve architectural expression, ensure safety and serviceability, and make rational and effective use of materials. The use of composite structures, which combine the advantages of various materials, has been the trend in structural systems for tall buildings. In both static and dynamic conditions, these high-rise structures ought to be able to withstand a variety of lateral loads, such as wind load and earthquake load. This study examines the responses of the Framed Tube, Braced Tube, structural systems to various parameters such as Story displacement, Story drift, Story shear, and time period. The analysis focuses on 60-story structures situated in Seismic Zone III with medium soil conditions. The static analysis of the structures is conducted using the linear static method, which involves wind load calculations using the force coefficient method. On the other hand, the dynamic analysis is performed using the response spectrum method, with wind load calculations carried out using the gust factor calculation method.

Probabilistic life‐cycle environmental impact of conventional and emerging steel frames in seismic zones

Probabilistic life‐cycle environmental impact of conventional and emerging steel frames in seismic zones

A future scenario earthquake and ground motion hazards for Kathmandu, Nepal

Since Nepal is an earthquake-prone country due to the collision of the Indian and Eurasian plates, it is crucial for its capital of Kathmandu to evaluate ground motion hazards from a future large earthquake. For this purpose, we constructed a realistic scenario earthquake with realistic rupture parameters in a likely location. To obtain the location, a new distribution of the rupture zones of large historical earthquakes along the Main Himalayan Thrust (MHT) was obtained by integrating the distribution from a previous study and the results of trench surveys. Global Navigation Satellite System observations indicated that the plate boundary is strongly coupled from the southern boundary of the MHT to a depth of approximately 10 km and there is almost no lateral change in the coupling. This implies that all regions along the MHT have similar rates of strain increase. Therefore, it is most probable that the rupture zone of the oldest previous event will rupture as a scenario earthquake. In the new distribution, the 1255 earthquake is the oldest. However, large earthquakes occurred in 1934 and 2015 within its rupture zone. Thus, we adopted the area obtained by removing the 1934 and 2015 rupture zones from the western part of the 1255 rupture zone. The relationship between the rupture area size and seismic moment of the 2015 earthquake lies between the scaling formulas for crustal earthquakes and plate-boundary earthquakes, but is closer to the former. Therefore, using this and the scheme for characterized source models, we determined realistic rupture parameters. We then simulated broadband ground motions in Kathmandu using these rupture parameters, our 3-D velocity structure models, and a hybrid method combining the finite-difference method and the stochastic Green’s function method. We obtained the peak ground accelerations (PGAs) of simulated ground motions, and calculated the seismic intensities in the Modified Mercalli intensity scale from the PGAs as indexes of hazards for Kathmandu. Intensities IX coincide with the center of the Kathmandu Valley, and intensities VIII and VII are found in the area surrounded by the sedimentary boundary and the southernmost part of the valley.Graphical abstract

Coseismic deformation and interseismic strain accumulation of the 2024 MS 7.1 Wushi earthquake in Xinjiang, China

On January 23, 2024, a magnitude 7.1 earthquake occurred in Wushi County, Aksu Prefecture, Xinjiang, China. The epicenter was located at the Maidan Fault, which is known for its left-lateral strike-slip and thrust characteristics within the Tianshan seismic zone. In this study, we used Interferometric Synthetic Aperture Radar (InSAR) and Global Navigation Satellite System (GNSS) observations to investigate the characteristics and mechanisms of both the coseismic and interseismic deformation. The main findings are as follows: 1) The InSAR coseismic deformation displays clear thrust characteristics, with a maximum relative displacement of ∼ 0.8 m along the line of sight, thereby indicating a thrust-type earthquake. 2) The majority of the slip during the earthquake occurred within a 60 km × 40 km area, with depths ranging from 4 to 26 km. The maximum slip of the fault was about 2.3 m, corresponding to a moment magnitude of 7.0. 3) The seismogenic faults primarily exhibit thrust-type movement characteristics during the interseismic period and possess a clearly defined locking state. The earthquake rupture depth aligns with the depth of locking during interseismic periods. 4) The seismogenic structure experienced compressive deformation in a north–south direction prior to the earthquake, with the epicenter located on the surroundings of the high-strain area, as indicated by the GNSS strain rate.