Low-rise Structures Research Articles

Optimization and analysis of hysteretic energy dissipators in reinforced concrete frame structures of five, 10 and 15 stories

Frame structures are especially affected by earthquakes, due to their low lateral resistance. The use of energy dissipators may be a suitable solution for these structures; however, the effectiveness of these devices is questionable in low-rise buildings. We therefore analyze the behavior of these devices in frame buildings with varying numbers of stories (five, 10 and 15 stories). The use of hysteretic dissipators is found to considerably reduce the displacements of the bare structures, in addition to significantly improving their resistance, although the absolute accelerations are not reduced. Taller, more slender structures require less rigid dissipators with lower yield forces than shorter, more rigid structures. The effectiveness of the dissipators is also demonstrated by increasing the number of stories of the structures. The effectiveness of the dissipators increases as the rigidity of the structure decreases, as observed for the highest frame structures considered in this research, or as also occurs with the characteristics of the seismic records, such as their impulsivity. A high level of rigidity of the structures (as in low-rise structures or those with a significant number of stiffening elements, such as walls or braces) may have a significant impact on the behavior of the dissipators, due to the low displacement of the bare structures, which reduces their effectiveness. Finally, given the complexity of the different designs for dissipators in the scientific literature, this research offers a new, simple way to design dissipators based on the structural characteristics of the bare frames. To carry out this research, a nonlinear static analysis (push-over) and dynamic analysis are carried out using two different characteristic records, as part of a search for the optimal characteristics of the devices and to analyze how each of them affects the structural behavior in buildings with different numbers of stories.

Development of novel low-cost isolator UMELI (unbonded mesh elastomeric layered isolator): experimental investigations

Seismic isolation is a highly efficacious method for reducing the seismic load on structures. This technique is widely adopted to safeguard structures from earthquakes. Despite the promising results demonstrated by numerous isolation techniques, their implementation remains a significant challenge, particularly in developing countries, due to the high costs associated with manufacturing. Therefore, a novel and affordable base isolation technique has been proposed, namely unbonded mesh elastomeric layered isolator (UMELI). UMELI consists of steel mesh sandwiched between the unbonded layers of elastomers, resulting in an affordable isolator to be used for lightweight, low-rise structures. One of the crucial characteristics of this novel isolator is that it does not require a specialised manufacturing process unlike other elastomeric isolators. In the present study, experimental investigations are conducted to evaluate the dynamic characteristics such as dynamic vertical stiffness, equivalent lateral stiffness, and equivalent viscous damping ratio of UMELI. Its characteristics were studied for different layered isolators and are compared with the unreinforced elastomeric isolator. The investigations have demonstrated the effectiveness of the UMELI by increasing its vertical stiffness and reducing lateral stiffness, thereby enhancing the isolation period with the addition of a steel mesh layer.

Seismic life-cycle cost evaluation of steel-braced frames: Comparing conventional BRBF with emerging SCVDF and HBF systems

In the past two decades, various self-centering bracing systems have been developed to enhance structural seismic resilience. However, compared to conventional bracing systems, their high initial cost and lower efficiency in controlling peak floor accelerations have reduced their economic benefits and limited their application in engineering projects. Accordingly, the self-centering viscous energy-dissipative brace (SCVDB) and the hybrid bracing system (HB), the synergistic combination of the SCVDB and buckling-restrained brace (BRB), have emerged as innovative approaches with exceptional capabilities in passive control over peak floor acceleration demand. Despite their promise, a comprehensive understanding of the life-cycle economic benefits of structures equipped with these bracing systems remains limited. This study aims to comprehensively highlight the life-cycle economic benefits associated with self-centering viscous energy-dissipative braced frames (SCVDFs) and hybrid braced frames (HBFs) compared to traditional buckling-restrained braced frames (BRBFs) across various structural heights using the improved HAZUS assessment methodology. Focusing on 4-, 8-, and 12-story buildings designed with BRBFs, SCVDFs, and HBFs, each maintaining identical peak inter-story drift ratios, the research conducts dynamic analyses combined with Monte Carlo simulations. Critical parameters such as residual inter-story drift (RID) limits defined for demolition, initial construction costs of the SCVDBs, and discount rates are considered. The analyses reveal that the expected annual earthquake-induced loss (EAL) for mid- and high-rise structures is more sensitive to RID limits than those of low-rise structures. The SCVDFs and HBFs exhibit lower EAL than BRBFs, even without considering the demolition situation. The RID limit, initial construction cost of SCVDBs, and discount rates significantly influence the relative economic benefits of SCVDFs and HBFs compared to BRBFs. In most scenarios, HBFs demonstrate superior economic benefits over SCVDFs. The HBF effectively utilizes the synergistic effects of SCVDBs and BRBs, substantially lowering initial construction costs and achieving favorable economic benefits across various structural heights within the considered parameter range.

DESIGN AND FABRICATION OF EMERGENCY FIRE RESCUE MACHINE

Building fires pose a serious risk to people, property and the environment. Numerous factors, such as human mistakes, electrical issues, heating systems, combustible items, might cause fire accidents. The effects of fire can be disastrous, resulting in accidents, fatalities, and significant building damage. Compared to fires in low-rise structures, high-rise building fire incidents pose numerous difficulties and a greater risk. High-rise building's vertical structures, greater resident capacity, and intricate infrastructure make fire fighters and evacuating residents more difficult to escape. It is essential to comprehend the causes, effects, and preventive strategies unique to high-rise fires in order to ensure occupant safety and reduce property damage. The disturbingly high rate of fire events, which are frequently brought on by inadequate fire prevention measures and damaged infrastructure, represent a serious threat to people's lives, their property, and the health of the economy. India can reduce the dangers connected with fire incidents in high-rise structures and guarantee the safety and well-being of its residents in the urban environment by giving priorityto the implementation of appropriate rescue systems. So in this project we are going to develop such machine which can help humans to get escape in the case of emergency situation in high rise building.

A Comprehensive Study on Net Zero Energy Buildings and Sustainable Construction Materials with Low Carbon Contents

One-third of the world's greenhouse gas emissions come from the building industry, with embodied carbon from the manufacture of building materials accounting for a sizable portion of these emissions. Prior research has mostly focused on examining the carbon emissions of low-rise structures, but it has failed to consider the significant influence that high-rise buildings have on a city's overall carbon emissions. Net-zero energy buildings (NZEBs) combine intelligent energy management strategies with conventional design knowledge to facilitate a sustainable and eco-friendly transition. The NZEB building revolution has the potential to become a long-term structural pillar for structures to come. The purpose of this study is to assess how various design factors and the embodied carbon in high-rise structures relate to one another. Additionally, the goal of this research is to keep annual consumer energy comfort in a home NZEB at its highest level without using any electricity from the electrical grid. In order to achieve long-term climate goals, our work emphasises the socio-economic advantages of adopting NZE buildings and further empowers consumer participation to minimise energy waste and carbon emissions. The findings provide a foundation for constructing high-rise structures in a more ecologically conscious manner to lower the structure's carbon emissions. The evaluation and comparison of the embedded carbon values takes into account the carbon emissions from the transportation and material manufacturing processes.

Seismic Risk Assessment of Built Environment in the Himalayan Foothill City of Dehradun, Uttarakhand

Himalayan foothill city of Dehradun in Uttarakhand state is located in a tectonically active region and is prone to earthquakes. The growth of Dehradun city is analysed using high resolution remote sensing datasets in the current study, with a focus on its vulnerability to seismic risks for single and double storey structures as the city is predominantly made up of low-rise structures. Analysis shows that 10% of urban expansion has occurred in spectral acceleration zones that are vulnerable to double-storey buildings, while 38% of urban expansion has happened in spectral acceleration zones that are vulnerable to single-storey buildings. The proposed land use as per Dehradun Masterplan 2041 is examined with reference to National Earthquake Hazards Reduction Program (NEHRP) for seismic regulating provisions. It is emphasized that the intended land use is incongruous in areas with higher spectral acceleration zones since it comprises structures with higher occupancy and the amenities required during post-earthquake rehabilitation. On the other hand, the open spaces are more appropriate in these locations, which will lessen susceptibility as the influence of seismic forces can be sufficiently attenuated. The present study, thus highlights the significance of including seismic risk information in urban planning processes in order to ensure resilient cities.

Experimental research on H-section beam-square steel column joints connected by self-tapping screws

This paper proposes a novel thin-walled steel beam-column joint entirely using self-tapping screws. Compared to bolted and welded connections, its advantages of easy construction, low precision requirements, and fast construction are suitable for low-rise steel structures. Four full-scale H-section beam-square steel column joints connected by self-tapping screws were tested and the force transfer mechanism was investigated. Three of the specimens were loaded monotonically at the beam ends. The effects of the L-shaped connecting plate thickness and the arrangement of stiffening ribs on the bending performance of the joints are analyzed. Monotonic loading tests have demonstrated that the increased thickness and the arrangement of stiffening ribs enhance the common forces in the clusters of self-tapping screws, thereby increasing the bending stiffness of the joints. One of the specimens was tested with cyclic loads. The cyclic loading test revealed that the hysteretic curve of the self-tapping screws connection is relatively full, with high energy dissipation capacity and low degradation of strength and stiffness. Finally, the improved component method proposed the calculation method of bending resistance of self-tapping connection joints. The calculation accuracy is within 10 %, which can be used as a reference for the design of bending resistance.

Analysis of Problems in the State of Heat Supply to Residential Buildings Using Heat Pump Circuits

Currently, the energy-efficient use of heat exchangers such as heat pumps is difficult in most regions of the Russian Federation. Most of the modern heat supply problems of built-in heat pump systems can be solved by organizational and technical means. First of all, it is necessary to streamline and compare foreign and domestic experience in the processes of design, production and installation work in the construction industry. The regulatory documentation also needs to take into account the climatic specifics of the regions and, accordingly, the modern building materials used in Russia. All the indicated points will directly affect the composition of the project documentation and will affect such sections as PPR and PIC. The purpose of the article is to analyze the main problems that hinder the formation of efficient production of thermal energy by heat pumps. The article uses general theoretical methods of cognition (analysis, synthesis, analogy, generalization, comparison), etc. As a result of the study, the problems of using heat pump devices on the territory of the Russian Federation are identified and formulated. These include gaps in regulatory documentation, the lack of incentive government programs, the lack of service support from most device manufacturers and the lack of a real physical and mathematical model of the software of the internal circuit of a heat pump system, on the basis of which it would be possible to predict the performance of the device within the life cycle of a construction project. The main organizational and technological solutions for the effective use of heat pump devices within the life cycle of low-rise buildings and structures are formulated.

Investigation on Residual Mechanical Properties of Galvanized Iron Cold-Formed Steel Sections Exposed to Elevated Temperatures

Cold-formed steel (CFS) sections are used to construct medium and low-rise structures designed to carry small-scale loads. CFS sections are manufactured without the application of heat. Therefore, it is crucial to comprehend the properties of CFS sections which are exposed to fire or elevated temperatures. To simulate the real- time fire exposure, an ISO Standard fire curve was used to heat the CFS sections. The objective of the study is to assess the residual mechanical strength of exposed sections after the elevated temperature test. The study aims to compile data for forecasting the degeneration of elements and to ascertain whether the structural components can be reused or replaced. The CFS sections were subjected to different temperatures, and after heating, two cooling methods were used to bring down to room temperature. The characteristics of the retrieved specimens, taken from exposed CFS sections were assessed using a tensile coupon test. The residual properties such as ultimate strength, yield strength, and elastic modulus were examined and reported. The influence of heating and cooling is more pronounced from the test results. A reduction in the yield and ultimate strength was noticed, and it was found to decrease as the heating intensity increases for air and water cooling respectively. In the case of yield and ultimate strength, the strength reduction is critical beyond 60 minutes. The elastic modulus was also found to be reducing with a similar trend. Based on the test results, reduction factors are proposed for ultimate strength, yield strength and elastic modulus. Reduction factors obtained for yield strength under 60 minutes of heating for air and water cooling is 0.575 and 0.557 respectively. In 120 minutes, the values are 0.400 and 0.329. Reduction factors obtained for ultimate strength under 60 minutes of heating for air and water cooling is 0.586 and 0.566 respectively. For 120 minutes, the values are 0.331 and 0.313.

Lateral behavior of low-rise aluminum alloy frames infilled with composite wallboards

In this paper, cyclic tests were conducted on three specimens to investigate the lateral performance of low-rise aluminum alloy frames infilled with composite wallboards. The test variables were set based on the opening on the composite wallboard and the rise-span ratio. The test phenomena indicated that the failure modes of the three specimens were the fracture of the core material of the composite wallboard and the shearing off of the blind-rivets between the composite wallboards and the aluminum alloy frame. Through the analysis of the data obtained from the strain gauges and the displacement transducers, the high rise-span ratio would lead to a noticeable pinching phenomenon in the hysteresis curves. It is also found that the opening on the wallboard resulted in a significant asymmetric shape in skeleton curves. Furthermore, the increase in the rise-span ratio had more significant impacts on the initial stiffness of the structure, leading to a reduction of 44%. Utilizing the relevant formula, the equivalent viscous damping coefficients for the specimens were calculated, which scaled to 0.2–0.3, 0.15–0.25, and 0.1–0.225, respectively. The lateral load-resisting capacities for the three specimens were evaluated using the characteristic values of load and displacement. And the desirable ductility of the three specimens was concluded for their ductility coefficients exceeding 3. This research aims to provide technical reference for low-rise structures with aluminum alloy frames infilled with composite wallboards.

Study on the Smoke Control Performance of Air Curtains in Emergency Stairwells of Multi-Unit Residential Buildings

Recently, in high-rise buildings, pressurization systems have been installed in emergency stairwells to prevent the ingress of smoke. However, in older buildings, these stairwells often lack pressurization systems, while in buildings with fewer stories, such systems are not typically installed. This study conducts simulations and a hot smoke test to evaluate the performance of air curtains in blocking smoke and toxic gases in outdoor emergency stairwells where additional pressurization equipment cannot be installed. The simulation results showed that air curtains installed perpendicular to the floor were useful at preventing smoke ingress, and higher wind speeds increased their effectiveness. It is believed that air curtains can partially reduce smoke ingress in stairwells of older buildings or low-rise structures without pressurization systems, thereby ensuring fire safety.

Seismic performance evaluation of a novel resilient steel frame with self-centering rocking columns and replaceable energy-dissipating connections for low-rise structures

To promote the seismic resilience of structures, minimizing both seismic damage and repair time is an effective way. Toward this goal, this paper proposes a novel resilient steel frame (RSF). The kernel structural components are the self-centering (SC) rocking columns and the replaceable energy-dissipating (ED) connections. The SC rocking columns equipped with shape memory alloy slip friction dampers (SMASFDs) reduce residual deformation and plastic damage of column bases, whereas the ED connections using shaped fuse steel plates mainly dissipate the input seismic energy. To demonstrate the seismic response characteristics, the numerical model of a three-story RSF is developed in OpenSees. The model is firstly validated by experimental results and then its seismic performance evaluations are carried out using three suites of earthquake ground motions associated with three seismic hazard levels. An equivalent conventional steel frame (CSF) with ED connections and rigid column bases is introduced as the counterpart. Incremental dynamic analysis (IDA) is conducted to obtain samples of the demand. Based on the IDA data, the joint fragility curves are generated using the joint probability density functions, taking into account the coupling relationship between the maximum and residual drift. The analysis results show that the RSF exhibits comparable maximum interstory drift and lower residual interstory drift, compared with the CSF. The introduction of the SC rocking column effectively protects the column from yielding and mitigates the residual deformation of the replaceable ED connections, therefore improving the reparability and seismic resilience of the structural system.

Relationships between wood properties and fire performance of glulam columns made from six wood species commonly used in China

Glued laminated timber stands as an increasingly favored engineered wood product in low-rise modern timber structures due to its commendable structural performance and carbon sequestration potential. Chinese standards presently fail to differentiate the effects of distinct wood species on the fire resistance of glulam. This study examined the charring rate and residual bearing capacity of glulam columns made from six commonly used wood species in China: poplar, Chinese fir, Douglas fir, hemlock, larch, and spruce. These materials exhibited densities ranging between 390 and 645 kg·m−³. ISO standard fire tests were conducted employing one- and two-adjacent-side fire exposures. Notably, the findings unveiled that high-density glulam columns demonstrated lower charring rates and slower rates of heat penetration. The two-adjacent-side fire configuration induced a corner effect, consequently amplifying the effective charring depth. The results showed a linear relationship between the ratio of diagonal to horizontal charring rate of the columns exposed to the two-adjacent-side fire and wood density. To enhance practical application, a formula was developed, employing the residual section method, to calculate the column's residual bearing capacity post two-adjacent-side fire exposure. This formula incorporates an adjustment depth to accommodate the corner effect, effectively mitigating the reduced wood strength within the pyrolysis zone.

An Investigative Study for the Seismic Performance of Composite-Reinforced Masonry Wall with Prestressing Technology

Prestressing technology is an effective way to improve the seismic performance of masonry structures such as concrete masonry wall. Therefore, bonded prestressing technology applied to integrated concrete masonry wall (ICMW) was proposed in this study, and a cyclic loading test on specimens with different section types was conducted. It was found that the prestressing technology rendered thinner and denser cracks on the load-bearing component of the specimens, while the failure mode remained unchanged. The prestressing technology increased the initial stiffness of the specimens and accelerated their stiffness degradation. Although the prestressing technology advanced the yield displacement of the specimens, it had a positive influence on the displacement ductility of the specimens. Additionally, the energy dissipation of the specimens increased with the deepening of the damage state, while the influence of the prestressing on the energy dissipation of the specimens decreased with an increased in the drift ratio. Furthermore, the equivalent viscous damping of the specimens with a rectangular and T-shaped section finally converged at 8% and 14%, respectively. Overall, the aforementioned findings indicate that the prestressing technology proposed in this study is a useful method for improving the damage propagation and seismic performance of ICMW, which could be used to construct low-rise masonry structures in the future.

Анализ обстановки с пожарами и их последствиями на территории Российской Федерации

Purpose. The article analyzes the situation with fires and their consequences on the territory of the Russian Federation in the period from 2018 to 2022. The features of fires recording and their consequences at the facilities with mass presence of people are considered. The following indicators were analyzed and compared: the number of fires recorded over a selected period of time, the number of people evacuated from buildings before the maximum values of hazardous fire factors were reached, as well as people rescued by fire and rescue units, the number of people injured and died in fires, direct material damage caused by fires, the number of fires with group fatalities (5 people and more). The relationship between these indicators and the number of storeys of the building has been revealed. The research is aimed at improving organizational and (or) technical measures intended to decrease the indicators that make up the unified state system of statistical recording of fires and their consequences. Methods. The authors used methods of system analysis, probability theory and statistics. Findings. The results of the analysis of data on fires and their consequences on the territory of Russia in the period from 2018 to 2022 are summarized. The number of fires, recorded starting from 2019, decreases every year by 35–40 thousand, with the exception of 2018 and 2019 (since changes to the Procedure for recording fires and their consequences came into force on January 1, 2019). The number of people died in fires during the period under review changes in a sinusoidal manner, i.e. from 2018 to 2019 there is an increase in fire deaths by 7.6 %, from 2019 to 2020 there is a decrease by 2.9 %, from 2020 to 2021 there is an increase by 1.9 % and from 2021 to 2022 there is a decrease by 8.6 %. The number of people injured in fires is decreasing every year: if in 2018 this figure was 9 642, then in 2022 - 8 140. The number of fires with group fatalities (5 people or more), as well as the number of people died in these fires, in the period from 2018 to 2022 changes in the same order as the number of people died in fires, that is, in a sinusoidal manner. Research application field. The results of the study can be used by specialists of the State Fire Service, who carry out official statistical recording and state statistical reporting on fires and their consequences, as well as by persons engaged in scientific or work activities in the field of fire and their consequences statistics. Conclusions. It is concluded that there is currently no promising trend for reducing the number of fires with group fatalities. At the same time, every year there is a decrease in the number of people saved in fires, this may be due to the fact that when a fire occurs, people manage to evacuate from buildings and structures before the maximum values of the HFF are reached. Due to the fact that the majority of fires occur in low-rise buildings and structures up to 5 storeys high, when developing, for example, a technology to reduce the fatalities in fires, as a result of peoples’ prompt rescue from the fire zone, it is worth paying special attention to the design features of rescue equipment for this high-rise (storey) category of buildings and structures. Development of special technical devices that operate using external power supply (for example, a car lift, a ladder-truck, etc.), or special technical devices that operate on the principle of smooth reducing drop energy when falling from a height, will reduce the amount of time required to conduct a rescue operation.

Impact of wind loads on columns or the building's geometric center in high-rise and low-rise buildings

Wind loading significantly impacts a building's structural integrity and induces substantial displacements, particularly at higher levels. Investigating these effects presents a challenging area of research. This study delves into the impact of wind loads on columns within the frame versus loads applied to the building's geometric center. It explores how these variations influence bending moment, shear force, and axial force at the column base in the structural frame. Additionally, it examines horizontal displacements across different floors in two buildings: one with seven floors and another with twenty-five. In the context of designing high or low-rise structures, allocating wind loads to the building's geometric center ensures a more secure structure compared to applying these loads solely to the columns of the frame. These conclusions derive from extensive research conducted. In the seven-story building, Case 2 exhibits a 406% increase compared to Case 1 in Q2-2. Moreover, Q3-3 shows a 107% rise, M2-2 a 203% increase, and M3-3 a 389% elevation. Notably, the largest displacement, measuring 561%, occurs at the 6th floor. In the twenty-five-story building, Case 4 surpasses Case 3 and Q3-3 by 366% and demonstrates a striking 1585% increase compared to M2-2.

Structural damage observed in reinforced concrete buildings in Adiyaman during the 2023 Turkiye Kahramanmaras Earthquakes

Türkiye, located in a highly seismic region, has witnessed a history of devastating earthquakes, with unprecedented consequences noted in February 2023 when two powerful earthquakes near Pazarcik (Mw 7.7) and Elbistan (Mw 7.6) struck Southern Türkiye, resulting in extensive casualties, structural damage, and the compromised integrity of over 500,000 buildings. This study, centered on the Adiyaman region, scrutinizes the immediate structural damage to various reinforced concrete buildings, including both low-rise and tall structures. Many of the damages were attributed to structural deficiencies, including inadequate seismic reinforcement detailing, non-compliance with earthquake-resistant construction techniques, substandard concrete quality, and poor workmanship. The quality of building materials is considered a critical factor in structural resilience during earthquakes. Substandard materials or compromised quality can substantially impair a building's ability to withstand seismic forces. These key findings address a critical gap in understanding the vulnerabilities of reinforced concrete buildings in the aftermath of the 2023 Türkiye Kahramanmaraş Earthquakes. With professional rescue experience from the field, the authors bring unique insights.

Development of fragility functions of low-rise steel moment frame by artificial neural networks and identifying effective parameters using SHAP theory

Estimating analytical fragility functions requires high computational costs due to numerous incremental non-linear dynamic analyses. This study employs a soft computing approach to reduce this process and increase estimation accuracy. Utilized a fragility database of low-rise steel moment structures designed for different versions of Iranian seismic design code, and six feedforward Artificial Neural Networks (ANN) with various architectures were trained to estimate the fragility function’s parameters to determine the most desired architectures. The neural networks used the design parameters (frames story, code edition of design, ductility, soil type, near- and far-field earthquake, and seismic zone factor and importance factor) as inputs. For each of the fragility function’s parameters (Median PGA and βs of damages: slight, moderate, extensive, and complete) as outputs, an ANN was trained. The best architect of ANN was selected based on the accuracy of the models from different statistical indicators and the most balanced of the inputs’ importance on the outputs using SHapley Additive explanations (SHAP) analysis. To demonstrate the accuracy of the selected architect, the coefficient of determination was estimated for all database values, and the fragility functions of four randomly chosen frames were compared. The high R2 value in most cases and the closeness of the predicted fragility curved with the actual one indicates the reliability of the ANN method for predicting the fragility function.

A hybrid clustering-based type-2 adaptive neuro-fuzzy forecasting model for smart control systems

The practical applicability of smart control systems suffers from the existence of uncertainty in the physical parameters, sensor measurements and external excitations. Effective methods and its ease of implementation are required in the real-time active control strategies. To this end, in this research, we introduce an overlapping clusters and Multilayer Extreme Learning Machine (ML-ELM)-aided interval type-2 Takagi-Sugeno fuzzy inference system for vibration mitigation of smart structures. The combined Fuzzy C-Means (FCM) and imperialist competitive algorithm (ICA) with respect to degree of fuzzy overlap between clusters was utilized for characterizing the upper and lower membership functions forming the antecedent part. Furthermore, indeterminacy was modeled as footprint of uncertainty (FOU) and automatically formed based on statistical characteristics of soft clusters. The consequent parameters were adjusted by hybridization of ML-ELM and overlapping clusters, then the adaptivity was guaranteed. The predictive accuracy and generalization capability of the proposed method were demonstrated over the estimation of active control effort. Finally, to prove the practicability of the implemented framework, it was applied to four high-rise, mid-rise and low-rise benchmark building structures equipped with active mass damper (AMD), active tendon and active bracing system (ABS). The obtained results demonstrated the higher predictive accuracy and generalization ability of the presented data-driven control scheme compared to the other standard technical machine learning strategies. This practical guideline is easy to implement and automates control engineering tasks in real-time applications, solving one of the most challenging aspects of smart control systems.

Seismic retrofit of low-rise structures using rotational viscoelastic dampers

In this research, the efficiency of a rotational viscoelastic seismic energy dissipation device is evaluated in a theoretical framework. Unlike conventional dampers which block the bays, the main advantage of this damper lies within its vertical installation scheme that provides open space in the bay and architectural flexibility. The proposed damper consists of a steel column with viscoelastic hinges at both ends that dissipate the seismic energy. Conventional viscoelastic dampers usually act under translational deformation, whereas it acts under rotational deformations in the considered scheme. The theoretical foundation is laid for the proposed damper and is verified by comparing the results with the analytical model of the damper. The developed device is proven to be versatile in terms of stiffness and energy dissipation which can be easily adjusted. The application and efficiency of this damper is validated by retrofitting a soft-first-story structure to fulfill the enhanced performance objective. The performance of the structure under a suite of earthquakes is compared before and after the seismic retrofit in terms of maximum interstory drift ratio and residual displacement.