Modern Construction Research Articles

Correlation between destructive and non-destructive evaluation to study of plastic waste aggregate mortar: a case study of mechanical proprieties

Non-destructive evaluation using ultrasonic pulse velocity (UPV) testing has extensive applications in the cement materials industry. Ultrasonic pulse velocity (UPV) test is accepted as alternative to destructive testing to determine the compressive strength, dynamic modulus of elasticity, and Poisson’s ratio, which are needed for structural design. In modern construction technology, the use of Plastic waste (PW) as a partial replacement to natural aggregates in a mortar mix is growing in popularity primarily because it reduces the initial capital cost of raw materials and the associated conservation in environment. In this regard, this study explains the correlations between mechanical proprieties, and UPV tests for mortar contains 25%, 50%, and 75% of waste aggregate of plastic. Mortar based on Plastic Waste (MPW) specimens were tested by direct, semi-direct, and indirect UPV. UPV measurements can be effectively used to determine the dynamic modulus of elasticity and Poisson’s ratio of Mortar based on Plastic Waste MPW. The dynamic elastic modulus and the Poisson’s ratio decreases for the same mortar composite when at increasing PW content. Thus, the incorporation of PW particles into the cement matrix confirms the capacity of composites to reduce the sound intensity and damp vibrations inside the composites. The results of this study will be significant for non-destructive evaluations of MPW, while additional recommendations for future studies are presented at the end of the paper.

Research on seismic performance of reinforced concrete structures reinforced with CFRP plates

In the modern construction industry, natural disasters such as earthquakes pose an increasingly prominent threat to reinforced concrete structures, which often lead to serious damage to the structures. Therefore, how to enhance the seismic performance of reinforced concrete structures has become an urgent problem to be solved in the field of construction. This study delves into the seismic performance of CFRP plates in strengthening reinforced concrete structures. Firstly, the material characteristics of CFRP panels were analyzed, including the mechanical and adhesive performance indicators of carbon fiber panels, and corresponding specimens were made. Subsequently, through specimen loading experiments, the performance of reinforced specimens and unreinforced specimens under load was compared. The experimental results show that prestressed CFRP plates can significantly increase the cracking load and enhance the seismic resistance of reinforced concrete structures. In addition, simulation tests were conducted using a finite element model. Through simulation testing, the load deflection curve of the specimen was obtained, revealing the influence of CFRP plates on beam stiffness. Especially in the critical stages of concrete cracking and yielding of tensile steel bars, carbon fiber board has a particularly significant effect on improving the stiffness of beams.

Coupled indoor air quality and dynamic thermal modelling to assess the potential impacts of standalone HEPA filter units in classrooms

The quality of the classroom environment, including ventilation, air quality and thermal conditions, has an important impact on children’s health and academic achievement. The use of portable HEPA filter air cleaners is widely suggested as a strategy to mitigate exposure to particulate matter and airborne viruses. However, there is a need to quantify the relative benefits of such devices including the impacts on energy use. We present a simple coupled dynamic thermal and air quality model and apply it to naturally ventilated classrooms, representative of modern and Victorian era construction. We consider the addition of HEPA filters with, and without, reduced opening of windows, and explore concentrations of carbon dioxide (CO2), particulate matter PM2.5, airborne viral RNA, classroom temperature and energy use. Results indicate the addition of HEPA filters was predicted to reduce PM2.5 by 40–60 % and viral RNA by 30–50 % depending on the classroom design and window opening behaviour. The energy cost of running HEPA filters is likely to be only 1 %–2 % of the classroom heating costs. In scenarios when HEPA filters were on and window opening was reduced (to account for the additional clean air delivery rate of the filters), the heating cost was predicted to be reduced by as much as − 13 %, and these maximum reductions grew to − 46 % in wintertime simulations. In these scenarios the HEPA filters result in a notable reduction in PM2.5 and viral RNA, but the CO2 concentration is significantly higher. The model provides a mechanism for exploring the relative impact of ventilation and air cleaning strategies on both exposures and energy costs, enabling an understanding of where trade-offs lie.

A Preliminary Study of 3D Printing Home Designs for Improving Efficiency and Sustainability of Indigenous Housing in Canada

Canada has been experiencing a significant housing crisis in recent years, especially in remote and Indigenous communities, yet most of the existing construction approaches have not been rapid, sustainable, and affordable enough to meet community needs. To address this challenge, this study explores the feasibility of 3D printed (3DP) housing and develops a design that is informed by Indigenous housing requirements and is realized through a physical design prototype tailored for the implementation of 3DP homes. Site visits and community engagement were integral parts of the research to help deliver invaluable insights that guided the design process, ensuring cultural sensitivity and inclusivity. The prototyped 3DP design offers efficient and sustainable solutions customized to the unique cultural and climatic needs of Indigenous communities in Canada. The final 3DP design seamlessly integrates traditional Indigenous architectural elements, such as a circular shape inspired by pit houses, with modern construction techniques, yielding a flexible, sustainable, and culturally pertinent home design. Future research work will be focused on how the proposed 3DP design can be adapted to enable mass customization to accommodate the diverse needs and preferences of Indigenous communities across Canada.

Unveiling the Constructed Identity of Santris: A Stylistic Exploration

This article aims at finding how santris living at modern pesantren construct their identities. The study is conducted at MBI AU a pesantren in Mojokerto, East Java with 156 respondents, 79 males and 77 females. The data are taken from their chats in WhatsApp groups for private contexts and from book communication and their public performance for public context. Interview is also conducted to support the data. The study reveals that at the macro level, santris, both males and females are not different from teenagers in general. At the meso level, santris are differentiated into the speakers of the east Javanese dialect (EJ), Non-east Javanese dialect (NEJ), and Non-Javanese (NJ). In this level, male santris of EJ tend to show a stronger Javanese identity compared to the females who show more accommodating natures. The NEJ and NJ santris are showing a higher tendency of doing relation of adequation toward the East Javanese dialect suggesting the drives for social allegiances and instrumental attachment toward the East Javanese dialect. Unlike the NJ santris who tend to show their home language as their self-constructed identity, the NEJ santris are using more bahasa gaul to distinguish themselves from the EJ santris.

Artificial Neural Network Prediction of Compliance Coefficients for Composite Shear Keys of Built-Up Timber Beams.

This article explores the possibility of predicting the compliance coefficients for composite shear keys of built-up timber beams using artificial neural networks. The compliance coefficients determine the stresses and deflections of built-up timber beams. The article analyzes current theoretical methods for designing wooden built-up timber beams with shear keys and possible ways of applying them in modern construction. One of the design methods, based on the use of the compliance coefficients, is also discussed in detail. The novelty of this research is that the authors of the article collected, analysed, and combined data on the experimental values of the compliance coefficient for composite shear keys of built-up timber beams obtained by different researchers and published in other studies. For the first time, the authors of this article generated a table of input and output data for predicting compliance coefficients based on the analysis of the literature and collected data by the authors. As a result of this research, the article's authors proposed an artificial neural network (ANN) architecture and determined the mean absolute percentage error for the compliance coefficients kw and ki, which are equal to 0.054% and 0.052%, respectively. The proposed architecture can be used for practical application in designing built-up timber beams using various composite shear keys.

Tensile test and hardness test on FCAW-GS welding results of AB/EH36Z35 material in 3G downhill position

Welding is a crucial aspect of the modern construction industry as it allows for efficient and reliable joining of metals. The purpose of this research is to evaluate the FCAW-GS welding process on AB/EH36Z35 material in the 3G downhill position. Additionally, the study aims to analyze the tensile and hardness test results of the welding. The research utilized the FCAW-GS welding method, with tensile testing conducted by the AWS D1.1/D1.1 M:2015 standard. Hardness testing was performed using the Vickers hardness test method with a test load of 10 Kgf, following the ASTM E92:2017 standard. The results of the tensile tests demonstrate that both specimens achieved high tensile strength. Furthermore, the hardness testing indicated no significant changes in material hardness in the HAZ and Line 3 areas. Consequently, this study's findings adhere to the quality standards outlined by AWS D1.1/D1.1M:2015 and ASTM E92:2017, making them a valuable reference for industrial welding processes

ЖҰҚА ИЗОТРОПТЫ ПЛАСТИНАЛАРДЫҢ ИІЛУІН ТАЛДАУ

In the field of modern construction, thin isotropic plates are widely used. The development of calculation methods and mathematical models for thin isotropic plates of rectangular shape is an important issue. The article examines the bending of a rectangular thin isotropic plate. The method of separation of variables is employed to derive the plate calculation theory. New formulas for the function of deflection and internal forces of the plate are determined. A simplified version of the classical theory is presented, defining the solution to the plate bending problem using simple polynomials. The values of the deflection function and internal forces of a rectangular thin isotropic plate are presented in the form of tables and diagrams. The obtained calculation results are compared with Navier's method and the finite element method. The results obtained completely coincide with the results obtained by other methods and thereby confirm the correctness of the proposed version of the theory.

Practical experience of installing an artificial base for industrial floors

The installation of artificial foundations for industrial buildings and constructions (industrial floors) is becoming more and more relevant in modern construction, as the number of satisfactory sites for development is decreasing, territories with complex geological and hydrogeological conditions are increasingly being used. A high-quality installation of an artificial base should ensure the durability, strength and stability of the structure. When preparing the site and arranging the artificial base, it is necessary to take into account such important factors as the type of soil, the level of groundwater, the expected load on the floor and the type of floor covering. Compliance with the requirements of regulatory and technical documentation, the use of quality materials and professional execution of work are critical for the successful construction of industrial floors. As part of the study, an overview and detailed description of the process of installing an artificial base for industrial floors was carried out on the example of a real construction, a warehouse complex with an area of 35,000 m² in the south-western outskirts of the city of Kyiv. The article highlights that the foundation installation process includes two main stages: site preparation and creation of artificial foundation layers. The preparation of the site includes cleaning and planning of the territory, removing and removing the fertile layer of soil, conducting engineering and geological studies and implementing measures for the engineering protection of the territory. The arrangement of the artificial base includes the compaction of the existing soil layers, the creation of new artificial base layers and their mechanical compaction in combination with the reinforcement of the layers with geosynthetics materials (geogrids). This study emphasizes the importance of a comprehensive approach to site preparation and artificial base installation, which allows for reliable and long-term operation of industrial floors, minimizing the risks of deformation and damage.

Peculiarities of using small-diameter bored piles for effective solving of geotechnical problems

Abstract. The peculiarities of the use of small-diameter drill piles in modern construction considered, with an emphasis on their advantages and areas of application in specific conditions. Two main types of piles distinguished: cast-in-place, which characterized by continuous reinforcement and filling with concrete or cement mortar, and composite, where the load transfers to reinforcing elements. Main advantages of small-diameter bored piles noted, including the possibility of performing work in confined spaces, reducing the level of noise and vibrations, a variety of drilling technologies, the possibility of application in geological conditions of varying complexity, etc. Particular attention paid to the areas of application of small-diameter bored piles, including the installation of new foundations, underpinning of existing structures, soil improvement and land-slide protection. The main groups of factors that can influence the choice of small-diameter bored piles as the main design decision for various fields of application considered, including: - physical factors (restricted access, remoteness of the area, distance of piles to existing structures); - subsoil factors (difficult geological conditions, soil liquefaction tendency); - environmental factors (sensitivity to vibration/noise, hazardous or contaminated soils); - necessity of adaptation to existing structures; - load/settlement requirements; - economic factors. Limitations for the use of small-diameter drill piles from the point of view of their efficiency described. An example of the effective practical use of small-diameter bored piles in the confined conditions of dense urban development in close proximity of metro tunnels with increased requirements regarding the level of vibrations and noise considered. The task of minimizing subsidence of the designed residential and office complex and the impact on surrounding buildings and structures solved. The compliance of the adopted design decisions confirmed by means of field tests, as well as using the results of settlements monitoring. Attention focused on the need for further improvement of design approaches and technological solutions to optimize the efficiency of small-diameter bored piles for solving geotechnical problems.

Analysis of the amount of latent carbon in the reconstruction of residential buildings with a multi-objective optimization approach

Purpose Due to the increase in energy demand and the effects of global warming, energy-efficient buildings have gained significant importance in the modern construction industry. To create a suitable framework with the aim of reducing energy consumption in the building sector, the external walls of a residential building were considered with two criteria of global warming potential and energy consumption. Design/methodology/approach In the first stage, to achieve a nearly zero-energy building, energy analysis was performed for 37 different states of thermal insulation. Then, the insulation materials’ life cycle assessment was performed. These results were used to find a set of optimal modes in the Pareto front by using non-dominated sorting genetic algorithm II multi-objective genetic algorithm. Thus, based on the data obtained from this method, it was possible to compare and choose different thermal insulation materials based on the distance from the Pareto front, reducing the environmental effects. Findings The results showed that replacing the windows was possible to save 3.24% in energy consumption. Also, selecting the proper insulation reduced energy consumption value by 63.13%. Finally, this building can save 69.31% of energy consumption compared to the base building by following the zero-energy building standard. As a result, the Pareto curve was introduced as a guide for the optimal design of the building’s wall insulation. Originality/value The proposed method provides designers with a framework for latent carbon analysis to access quickly and select optimal scenarios. It can also be used without restrictions for other decisions with different goals and criteria.

A generative design-based optimization model for multi-objective construction site layout planning

PurposeGiven the growing interest in modern construction techniques and the emergence of innovative technologies, construction site layout planning research has progressively been investigating approaches to adopt innovative concepts and incorporate renewed approaches to improve widespread efficiency. This research develops a decision-making tool that optimizes construction site layout plans. The developed model targets two main objectives: minimizing material transportation costs and maximizing safety by optimally placing facilities on construction sites.Design/methodology/approachA novel approach is devised based on the integration of Building Information Modeling and Generative Design (BIM-GD). This engine is used to optimize the multi-objective site layout problems to identify layout alternatives in the early project stages. Parametric modeling uses Dynamo to construct the model and explore constraints initially. Finally, the GD environment is utilized to create different design alternatives, and then the decision-making procedure selects the most appropriate design alternative. Additionally, a case study is applied to validate the effectiveness of the developed model.FindingsThe results indicate the effectiveness of the proposed GD tool and its potential for more complex applications. The GD engine examined optimal layout plans, balancing different objectives and adhering to appointed geometric constraints. A case study was conducted to assess the model's effectiveness and showcase its suitability. Construction Site Layout Planning (CSLP) is an essential step in design that can influence considerable aspects, such as material transportation expenses and different safety standards on the site. Employing visual programming for parametric modeling within Dynamo-Revit creates an expedient and user-friendly platform for planning engineers who may require more programming expertise to create and program algorithmic models visually. Utilizing GD in CSLP has proven to be a powerful tool with consequential prospects for improving applications and executing more models.Practical implicationsThe findings from this framework are intended to help construction practitioners select the most appropriate site layout during early project stages while incorporating different safety criteria inside construction sites to alleviate actual safety risks.Originality/valueA new approach is proposed that utilizes an integrated BIM-GD engine to optimize multi-objective site layout problems. This approach targets two main objectives: minimizing material transportation costs and maximizing safety by optimally placing facilities in construction sites.

COMPARATIVE ANALYSIS OF CALCULATION METHODS OF CLT STRUCTURES

One of the important tasks of modern construction is the search for new constructive solutions and the introduction of new construction technologies. Cross-Laminated Timber (CLT) technology is a new material for Ukraine that has proven itself in Europe and America as effective and environmentally friendly with many advantages. Since CLT panels are not widely distributed, studied and do not contain references in the normative literature in Ukraine, the study of these structures is extremely relevant. This paper presents a comparative analysis of the CLT calculation methods of panels: using the RFEM 6 and LIRA-FEM software and analytical calculation. The research concerns three types of panels: three-layer, five-layer, and seven-layer under the action of a load of 1.5 and 5.0 kN/m2. The main parameter under consideration is the vertical deflection of the panels. The results of all calculations are collected in one table, where you can analyze the discrepancy between different methods of calculating the CLT structures.

Numerical simulation of steel-concrete composite beams and slabs at elevated temperatures

Steel-concrete composite beams with shear studs providing composite action between the concrete slabs and steel beams are widely used in modern steel-framed building construction. Three-dimensional finite element modelling has been a viable option for investigating the fire behaviour of composite beams. Although many finite element models are available in the open literature, most of them are simplified models verified by limited test data. Meanwhile, early test data often did not have all the required information for finite element simulation, and some assumptions need to be made. But more detailed test data are now available in the open literature for steel-concrete composite beams, which can be used to develop a generalised finite element model. In addition, National Institute of Standards and Technology has proposed new stress-strain models for steels at elevated temperatures, which can be compared with the more widely adopted Eurocode 4 steel material models in simulating composite beams. Accordingly, this paper selected 22 specimens, including two reinforced concrete slabs, 12 composite beams with reinforced concrete slabs, two composite slabs with profiled steel sheeting, two steel-concrete composite push test specimens with profiled steel sheeting, and four composite beams with profiled steel sheeting, from nine references to verify the developed finite element model. The proposed finite element model can capture different failure modes of composite beams, such as steel yielding/local buckling, concrete cracking/crushing, debonding of profiled steel sheeting, and stud fracture, which is crucial to comprehend the composite beam behaviour at elevated temperatures.

Enhancing precision and efficiency in English bond brick masonry: novel unified templates approach

PurposeThis study aims to enhance the precision and efficiency of English Bond brick masonry by developing three unified templates: Tc, T1, and T2. These templates are designed to address the complexities in the placement of bricks, particularly queen closers and brickbats, in English Bond patterns.Design/methodology/approachThe research introduces a unique numbering system integrated within each template to facilitate accurate brick placement. Template Tc is designed explicitly for corner masonry, while T1 and T2 are developed for linear masonry along the X and Y directions, respectively. The approach standardizes the bricklaying process, ensuring proper alignment and bricks overlap.FindingsApplying these templates significantly improves the efficiency and pace of English bond brick masonry. They simplify the construction process, reduce errors, and enhance the overall quality of masonry work. The study demonstrates that using these templates results in consistent and high-quality brickwork, surpassing traditional speed, efficiency, and accuracy methods.Originality/valueThis study contributes a novel, systematic approach to bricklaying in English Bond masonry. The introduction of unified templates aids in skill acquisition for professionals and learners, ensuring flawless execution of masonry projects. This innovative approach holds great value in modern construction practices, promoting standardization and excellence in masonry work.

Determination of longitudinal stability of strip in rolling cage – non-drive dividing device system

In modern industrial and civil construction, various rolled metal products are used in greater volumes. The largest share of them is occupied by rebar profiles produced at small-grade mills. The ever-growing demand for rebar rolling requires an increase in production volumes. The most promising technology in this regard is rolling – separation, which, with relatively low material costs, allows operating rolling mills to significantly increase the production volume of rebar profiles while reducing energy consumption. However, despite the obvious advantages of rolling – separation technology using non-drive dividing devices, it is very difficult to correctly determine the rational modes of conducting the process taking into account the peculiarities of production and equipment layout, which is due to insufficient theoretical knowledge. One of the main problems is determination of the permissible distance in the rolling cage – non-drive dividing device system. The conducted studies allowed us to propose a dependence for determining the maximum permissible distance in the rolling cage – non-drive dividing device system for reasons of longitudinal stability of the strip, taking into account the size and shape of cross-section of the split articulated profile, the nature of pinching, and the backstretch stress. It was experimentally established that when determining the permissible distance between rolling cage and non-drive dividing device, it is advisable to take the length reduction coefficient equal to 0.7.

Importance of Modern Construction Technique for optimization of cost and time

Importance of Modern Construction Technique for optimization of cost and time

Kinematics and spatial structure analysis of TBM gunite robot based on D–H parameter method

In modern tunnel construction, TBM (Tunnel Boring Machine) plays a very important role. In response to the needs of tunnel wall reinforcement and TBM automated construction for tunnel construction, a shotcrete mechanism mounted on the TBM is designed. In order to evaluate the kinematic performance of the mechanism, this paper studies the forward and inverse kinematics and spatial architecture of the TBM shotcrete robot. Firstly, based on the D–H parameter method, the number of joints and links is determined and structural analysis is performed to obtain the robot's forward kinematics equation, achieving the mapping between joint space and pose space. Then, by determining the joint variables, the mapping of the end tool in Cartesian space is achieved. Finally, based on the Monte Carlo random sampling method, the workspace of the robot is constructed, and its reachability and flexibility within the robot workspace are evaluated. The performance of the device is verified by building a prototype, which meets the requirements well. Through the research in this paper, it can provide theoretical basis and guidance for the design and control of the shotcrete robot.

Performance-based seismic design of Ultra-High-Performance Concrete (UHPC) bridge columns with design example – Powered by explainable machine learning model

Ultra-high-performance concrete (UHPC) has rapidly become a material of choice in modern construction owing to its favorable properties, such as superior strength, toughness, and durability. Yet, accurate quantification of damage states using appropriate engineering demand parameters (EDPs) remains a significant challenge in the performance-based seismic design (PBSD) of UHPC columns. This gap is especially evident in the scarcity of research focused on the PBSD of UHPC columns. Therefore, this study aims to develop an explainable machine learning (ML) powered predictive model for the drift ratio limit states of UHPC bridge columns across four damage states. To achieve this, a fiber-based numerical model was developed and then validated against large-scale experimental results of UHPC columns tested under reverse cyclic loading. The Latin hypercube sampling method is employed to generate a comprehensive database of UHPC bridge columns (10,000 UHPC columns), considering uncertainties across a spectrum of design factors, including column geometry, material characteristics, reinforcement ratio, and axial load ratio. The drift ratios at the initiation of four damage states are determined using the numerical model. Subsequently, the power of the ML algorithm is leveraged to introduce drift ratio limit states for UHPC columns that capture the onset of four different damage states. The efficacy of the developed model is assessed using a range of statistical metrics, including the composite fitness score, DX% metrics, coefficient of determination, root mean squared error (RMSE), normalized RMSE, and mean absolute error, which demonstrated high predictive accuracy of the drift ratio limit states on both the training and unseen or test datasets. Furthermore, a model-agnostic Shapley Additive exPlanation (SHAP) is used to explain the output of the model and examine the influence of various design factors on drift ratio across the damage states. Notably, the axial load ratio and aspect ratio are found to be major factors in determining the drift ratios across the damage states. The developed model is deployed into a software tool in order to enable its practical application. Additionally, the implementation of the developed model in the context of PBSD is illustrated through a design example. Furthermore, the study proposed capacity uncertainty parameters to aid the fragility assessment of UHPC columns. Finally, the proposed model, along with capacity uncertainty parameters, is used for the fragility assessment of UHPC columns reinforced with varying steel bar grades. The results demonstrate the less vulnerability of UHPC columns reinforced with higher bar grade, yet the effect of bar grade lessens at severe damage levels.

BASIC PRINCIPLES OF CONSTRUCTION AND REPAIR OF CIVIL BUILDINGS USING BIM-TECHNOLOGIES

Problem statement. The peculiarities of the construction of civilian buildings consist in ensuring a reduction in energy consumption, costs for their maintenance and a harmonious combination with the urban environment; the cost reduction of buildings that are rented out; reducing the duration of civil buildings construction. In the process of building civil buildings, a large number of uncoordinated operations may occur, which lead to a decrease in the quality of the finished housing and material losses. Thanks to the use of BIM-technologies, it is possible to maximally take into account such inconsistent moments and make the construction process more efficient. Purpose of the article is to analyse the practical experience of BIM-technologies using for the construction and repair of civil buildings, including the use of concrete with polymer addmitures as a material for the repair of civil buildings from the point of view of increasing their service life. Conclusion. Today, the sphere of construction production is changing quite dynamically. More recently, there were no materials that would allow to achieve qualitatively different results. These are primarily polymer additives for concrete, which are currently available in large quantities. However, the use of polymer additives requires a full knowledge of their properties. This is necessary for the reason that such components, in case of non-compliance with the rules of their use, can nullify the efforts of all project participants. If you have a sufficient level of knowledge about the components used by this or that production, there are situations when weather conditions can radically change the result of construction work, but not always in a more favorable direction. It is important to take into account not only information about the interaction of many factors, but also the need to build a civil building that meets the thermal and technical characteristics of modern construction. Not only the profit from the planned project depends on this, but also the living conditions and comfort of many generations of the population of our country.