Abstract This paper presents a comprehensive review of post-tensioned (PT) precast jointed systems as a resilient structural solution for resisting lateral loads. These systems offer enhanced seismic performance by combining self-centering behavior with controlled energy dissipation, thus minimizing residual displacements and structural damage. The review traces the historical evolution of PT systems applied to frames, columns, walls, and bridge components, highlighting experimental and analytical investigations over the past three decades. Special emphasis is placed on the role of initial prestressing force, energy dissipation reinforcement, and joint detailing in improving seismic resilience. The paper also explores fragility analyses that evaluate the probability of exceeding specific damage states under varying drift demands. Comparisons with conventional monolithic systems demonstrate the superior recentering and stiffness retention capabilities of PT joints. Challenges such as limited hysteretic energy dissipation, toe crushing, and compatibility with seismic code provisions are addressed through the integration of external dampers, steel jacketing, and hybrid joint designs. Additionally, recent innovations such as embedded damping cores, friction devices, and hybrid rocking-wall systems are examined for their potential to improve performance in moderate to high seismic zones. The review concludes with a critical discussion of international code provisions and identifies gaps in existing standards that hinder broader implementation. Recommendations are made to guide future research toward developing practical, codified solutions for PT systems with consistent seismic performance.
Systems of building construction. Including fireproof construction, concrete construction
Abstract This study investigates the effects of tuff powder (TP) on the macroscopic performance and microstructural characteristics of self-compacting concrete (SCC) subjected to freeze–thaw cycles (FTCs). SCCs with 0%, 15%, and 30% TP replacement were assessed for compressive strength, splitting tensile strength, and freeze–thaw durability. Additionally, the micropore structure of SCC paste was analyzed using mercury intrusion porosimetry (MIP). The results indicate that increasing the TP replacement ratio leads to a reduction in compressive and splitting tensile strengths. However, the mass loss rate decreases, and the relative dynamic elastic modulus (RDEM) increases under the same FTCs with higher TP content. Furthermore, the proportion of harmful and multi-harmful pores in SCCs diminishes as TP content increases, suggesting that TP enhances the frost resistance and durability of SCCs. A damage model was employed to predict the evolution of mass loss rate and RDEM, demonstrating a high degree of accuracy in fitting experimental data. The predictive results confirm that TP incorporation significantly extends the service life of SCC, enhancing its durability in severe freeze–thaw regions.
Systems of building construction. Including fireproof construction, concrete construction
Abstract This study aimed to reduce cement usage and promote effective utilization of industrial by-products by developing a quaternary mortar mix design using Taguchi–grey relational analysis (GRA). Municipal solid waste incineration fly ash (MSWIFA), ground granulated blast furnace slag (GGBFS), and fly ash (FA) were used as supplementary cementitious materials, and their optimal replacement ratios were proposed in the mix design. The optimal levels were analyzed in terms of the flowability, compressive strength, and cost analysis. The number of experiments and mix combinations was reduced by approximately 33% using the L9 orthogonal array. The S/N ratios obtained from the measurements, along with ANOVA, enabled the evaluation of the contribution of each parameter to individual responses. Based on the Taguchi–GRA method, the optimal mix design was determined to be 2.5% MSWIFA, 20% GGBFS, and 20% FA, which yielded the most favorable balance of flowability, compressive strength, and cost analysis. This result was verified through confirmatory experiments. The experimental validation supports the effectiveness and validity of the Taguchi–GRA-based mix design approach for optimizing quaternary mortar compositions.
Systems of building construction. Including fireproof construction, concrete construction
Valery G. Shamonin, Alexey V. Golkin, Stanislav A. Zuev
et al.
The possibility of solving the problem of optimal choice of evacuation exits along one or both sides of curved corridors, both sides of which are arcs of parabolas, is considered for subsequent minimization of mixing of human flows (and, accordingly, prevention of congestion during movement of people) during evacuation in case of fire or other emergency situations. The issues of calculating the distances between evacuation exits on both corridor borders, the local width of the corridor, the division of corridors into wide and narrow, as well as the application of the method of local variations are considered.
Systems of building construction. Including fireproof construction, concrete construction
Ahmed A. Mahmoud, Belal K. El Gani, Tarek S. Mustafa
et al.
Abstract This research presents an experimental, analytical, and numerical study to predict the flexural behavior of reinforced concrete hidden and wide beams embedded in slabs. The experimentally studied parameters of testing eight specimens include beam depth, beam width, and beam eccentricity from the column. The obtained test results were compared to the predictions of finite element analysis using the ANSYS program. A numerical parametric study was conducted by the ANSYS program to explore other parameters affecting the ultimate flexural strength of beams. The studied parameters encompass concrete compressive strength, steel reinforcement strength, bottom reinforcement ratio, top-to-bottom reinforcement ratio, and web reinforcement ratio. The results revealed that an increase in beam depth led to higher ultimate load and secant stiffness, along with a decrease in deflection. The increase in beam width significantly affected beam depth, resulting in increased ultimate load and secant stiffness and a slight decrease in deflection. The increase in beam eccentricity from the column resulted in a decrease in ultimate load and secant stiffness while increasing the deflection. Comparisons between experimental and numerical results were made against calculations based on the ECP 203-2017 and ACI 318-19 codes, and the comparison yielded satisfactory results.
Systems of building construction. Including fireproof construction, concrete construction
Abstract This study utilized machine learning (ML) models to investigate the effect of physical and chemical properties on the reactivity of various supplementary cementitious materials (SCMs). Six SCMs, including ground granulated blast furnace slag (GGBFS), pulverized coal fly ash (FA), and ground bottom ash (BA), underwent thorough material characterization and reactivity tests, incorporating the modified strength activity index (ASTM C311) and the R 3 (ASTM C1897) tests. A data set comprising 46 entries, derived from both experimental results and literature sources, was employed to train ML models, specifically artificial neural network (ANN), support vector machine (SVM), and random forest (RF). The results demonstrated the robustness of the ANN model, achieving superior prediction accuracy with a testing mean absolute error (MAE) of 9.6%, outperforming SVM and RF models. The study classified SCMs into reactivity classes based on correlation analysis, establishes a comprehensive database linking material properties to reactivity, and identifies key input parameters for predictive modeling. While most SCMs exhibited consistent predictions across types, GGBFS displayed significant variations, prompting a recommendation for the inclusion of additional input parameters, such as fineness, to enhance predictive accuracy. This research provided valuable insights into predicting SCM reactivity, emphasizing the potential of ML models for informed material selection and optimization in concrete applications.
Systems of building construction. Including fireproof construction, concrete construction
Abstract The present study pertains to the flexural behavior of RC beams with openings and non-metallic (GFRP) reinforcement. The main goal of preferring GFRP reinforcement over the conventional steel reinforcement was to safeguard the beams against the reinforcement corrosion. The presence of multiple regular transverse openings throughout the beam length increases the susceptibility of reinforcing bars to corrosion as the larger contact area in these beams with the outside environment increases the ingress of corrosive agents. Within the scope of the study, a total of 8 RC beams, including two reference beams without web openings, were tested under four-point bending. The test parameters were the flexural reinforcement ratio, the presence of short stirrups in the chords, and the presence of diagonal reinforcement spiraling around the openings. Since GFRP stirrups are difficult to bend, each stirrups was formed by connecting four individual FRP bars around the longitudinal bars. The opening circular geometry was adopted to avoid stress concentrations around the sharp corners of opening and to facilitate the placement and fixing of different schemes of reinforcement in the beams. The present tests depicted that the diagonal reinforcement around the openings have considerable contribution to the flexural behavior of RC beams with GFRP reinforcement and with multiple regular transverse openings. The RC beams with openings were able to approach their analytical flexural capacities in the presence of diagonal reinforcement for both moderately and heavily reinforced beam groups. The analytical deflection predictions of GFRP-RC beams with openings showed a good agreement with experimental data.
Systems of building construction. Including fireproof construction, concrete construction
The aim of the study is to create a system of indicators that will improve the management of fire departments, minimize risks to personnel and property and ensure prompt response to emergencies.
The article analyzes the existing methods and models used to optimize the activities of fire departments. The special attention is paid to mathematical modeling, which allows taking into account the type of object, building density, availability of water sources and other factors. Based on this analysis there are developed indicators taking into account economic feasibility, efficiency and safety in the management of fire forces.
The proposed system of indicators addresses the basic principles of fire safety, including assessment of the level of risk to personnel, responsiveness, effectiveness of the technologies used and the system resilience to emergency situations. Among the main indicators there are «reaction time», «level of training and qualification of personnel», «availability of material resources» and «use of innovative technologies».
The developed system is universal, its application is possible both at industrial and civil facilities.
Systems of building construction. Including fireproof construction, concrete construction
Abstract Recently, strong earthquakes are continuously occurring all over the world regarding, repair and strengthening of non-seismically designed structures. Presently, fiber-reinforced polymer (FRP) surface-bonding method is used as a quick and easy way to retrofit and strengthen damaged columns and walls. However, the inherent problems of the FRP surface-bonding method of bond degradation are adhesive interfaces and FRP sheet aging during service-life still. In order to overcome these problems, it is necessary to develop new materials and techniques that can induce monolithic behavior between the structural member and retrofit material by eliminating the bonding interface. One solution is to use repair and strengthening using stiff-type polyurea (STPU) developed as a seismic retrofitting material which can be applied by spraying method. In order to investigate the retrofitting effect of STPU, pseudo-dynamic push–pull test and dynamic shaking table tests are performed. The novelty of the study is that the RC columns strengthened with a newly developed STPU are tested for pseudo-dynamic (i.e., also represents the static behavior) and dynamic behavior. From the test results, overall strengthening effect of the STPU for both static and dynamic loading conditions can be understood, which can be used for retrofitting of concrete structures all over the world. The study results are discussed in detail in the paper.
Systems of building construction. Including fireproof construction, concrete construction
Vadim V. Zykov, Andrey N. Gladkikh , Nikolay Yu. Pivovarov
et al.
The article deals with the issues of tactical support of the operating official actions in a fire with the use of robotic systems. There are defined routine tasks, functions and conditions for justifying the choice of a robotic complex usage tactics in fire extinguishing. The necessity of developing and improving existing tactical approaches to the robotic complexes using by fire and rescue units is substantiated. The list of scenarios for the robotic complexes use can be formed on the basis of analysis and by developing documents for preliminary planning of fire and rescue unit actions of those objects of protection, fire protection of which is carried out by units equipped with appropriate robotic complexes.
Systems of building construction. Including fireproof construction, concrete construction
Viktor D. Volkov, Oksana V. Chirko, Evgeny V. Valyaev
The article discusses a modular robotic self-propelled installation on a caterpillar track (hereinafter referred to as a self-propelled installation). It is delivered on a special fire truck for fire extinguishing. With different equipment it is capable to cut out windows in the wall of a burning tank with oil products and to feed foam inside. There is presented the composition of modules as well as a detailed description and technical capabilities of a self-propelled installation for extinguishing a tank with oil products.
Systems of building construction. Including fireproof construction, concrete construction
Abstract In pavement engineering, cement grouting material is widely used to pour into large void asphalt concrete to prepare semi-flexible composite mixtures. It plays an essential role in the performance of the semi-flexible composite mixture. To meet specific engineering requirements, various additives are mixed into the grouting material to improve the physical and mechanical properties. As a result, the uncertainty of the grouting material is also more significant as the complexity of material composition increases during the material design. It will bring some unknown risks for the engineering application. Hence, it is necessary to quantize the uncertainty during the material design of the grouting material and evaluate the reliability of the material formula. In this study, a novel framework of material design was developed by combing the Multioutput support vector machine (MSVM), Bayesian inference, and laboratory experiments. The MSVM was used to approximate and characterize the complex and nonlinear relationship between the grouting material formula and its properties based on laboratory experiments. The Bayesian inference was adopted to deal with the uncertainty of material design using the Markov Chain Monte Carlo. An optimized formula of the cement grouting material is obtained based on the developed framework. Experimental results show that the optimized formula improves engineering properties and performance stability, especially early strength. The developed framework provides a helpful, valuable, and promising tool for evaluating the reliability of the material design of the grouting material considering the uncertainty.
Systems of building construction. Including fireproof construction, concrete construction
Andrey L. Chibisov, Dmitry V. Fedotkin, Elena A. Soina
et al.
The methodology was developed and there were obtained experimental data on the dependence of aerosol concentration on specific surface and combustion time of alkali metals. Adequacy of mathematical model of process of aerosol formation during combustion of alkali metals is proposed and evaluated. The kinetic dependencies of the change in the concentration of aerosol in the gas phase on the combustion time are also determined. It enables to calculate the amount and concentration of aerosol of alkali metals formed during their combustion.
Systems of building construction. Including fireproof construction, concrete construction
Abstract Rubberized concrete is an environmentally friendly building material that mixes rubber particles from old automobile tires into normal concrete in place of fine aggregate. The addition of rubber particles can improve the abrasion resistance of normal concrete observably. It has a good application prospect in hydraulic engineering, especially in the concrete building parts with high abrasion resistance. However, there are few experimental studies on the abrasion resistance of rubberized concrete, and the influence law and mechanism of rubber particles on the abrasion resistance of concrete are not understood. In this paper, the abrasion resistance of rubberized concrete is studied using the underwater-steel-ball method. The results show that rubber particles increase the slump of concrete mixtures. The abrasion resistance of rubberized concrete increases significantly with increasing rubber particle content, whereas the compressive strength decreases linearly. For the same rubber particle size and content, the abrasion resistance of rubberized concrete positively correlates with compressive strength and larger rubber particles significantly improve the abrasion resistance. Rubber particle content is the factor that most strongly affects abrasion resistance of rubberized concrete, followed by the compressive strength. Rubber particle pretreatment methods of NaOH + KH570 can significantly improve the abrasion resistance of rubberized concrete.
Systems of building construction. Including fireproof construction, concrete construction
Abstract Experimental investigation on seismic performance of RC shear walls reinforced with CFRP bars in boundary elements to enhance the resilience was presented which is expected for stable resistance capacity and small residual deformation. Six RC shear walls reinforced with CFRP bars as longitudinal tensile materials in boundary elements were tested under reversed cyclic lateral loading while subjected to constant axial compression with different axial load ratios of 0.17, 0.26 and 0.33, respectively. Two forms of stirrups were used for each axial load ratio, which were rectangular and circular stirrups in boundary elements. A reference specimen, ordinary RC shear walls, was also introduced to certify the excellence of CFRP bars. The test results indicated that the walls utilizing CFRP bars had small residual deformations and residual crack widths. Lower crack propagation height and larger concrete crushing region, bearing capacity and equivalent viscous damping coefficient (EVDC) could be observed with the increase of axial load ratios. The effects of stirrup forms on experimental results had a relation to the axial load ratio. When the axial load ratio was small, the shear walls with circular stirrups had better energy dissipation than that with rectangular stirrups at a given drift level, while the cumulative energy dissipation (CED) were similar. With the increase of axial load ratio, the walls exhibited similar energy dissipation at the same drift level, however, the shear walls with rectangular stirrups had larger CED.
Systems of building construction. Including fireproof construction, concrete construction
Abstract This paper investigated the working behavior characteristics of six reinforcement concrete (RC) beams subjected to bending based on the numerical shape function (NSF) method and structural stressing state theory. Firstly, the structural stressing state mode is expressed based on the generalized strain energy density (GSED) derived from the measured strain data. Then, one of the Carbon Fiber Reinforced Plastic (CFRP)-strengthened RC beams is taken as an example and the leap characteristics of RC beam’s stressing state are detected by applying the Mann–Kendall (M–K) criterion, updating the existing definition of the structural failure load. Accordingly, the stressing state modes and strain fields of the CFRP-strengthened RC beam are proposed to reveal their leap characteristics. Furthermore, through comparing the working performance of six RC beams, the effects of different strengths and different reinforcement ratios on CFRP strengthening performance are investigated. Finally, the NSF method is applied to reasonably interpolate the limited strain data for further revealing the stressing state characteristics of the RC beams. The research results explore a new analysis method to conduct an accurate estimation of the structural failure load and provide a reference for the future design of CFRP-strengthened RC beams.
Systems of building construction. Including fireproof construction, concrete construction
Abstract Basalt fiber reinforced polymer (BFRP) rebars reinforced coral aggregate concrete is a new type of concrete used in ocean engineering. In order to investigate the bond performance between BFRP rebars and coral concrete, 30 pull-out tests were carried out in 10 groups with different diameters of BFRP rebars, bonding lengths and strength of the coral concrete. The results show that good bonding between BFRP rebars and coral concrete were achieved. The main failure modes can be categorized as BFRP rebars pull out destruction, splitting failure of coral concrete and BFRP rebars fracture. The bond slip ($$\tau{\text{-}}s$$ τ-s ) curves of the BFRP rebars and coral concrete were obtained during the tests. It was found to be similar to the common concrete using fiber reinforced polymer (FRP) bars. The bond-slip relation can be roughly divided into micro-slip phase, slip phase, decline phase, and the residual stress stage. The bond between BFRP rebars and coral concrete increases with the increase of the bond length and diameter of BFRP rebars, but the average bond stress will decrease. Moreover, increasing the strength of coral concrete is effective to improve the bond performance of BFRP rebars. In this paper, the continuous bond slip model (Gao et al. in J Zhengzhou Univ 23:1–5, 2002) was used to represent the $$\tau{\text{-}}s$$ τ-s constitutive relationship of BFRP rebars and coral concrete. The analysis show that the proposed model has a high degree of accuracy in representing $$\tau{\text{-}}s$$ τ-s curve of BFRP rebars and coral concrete.
Systems of building construction. Including fireproof construction, concrete construction