Construction Field Research Articles

PERFORMANCE CHARACTERISTICS OF A MODIFIED COMPOSITE MATERIAL CONTAINING INORGANIC LIGHTWEIGHT AGGREGATES

A modified thermal and sound insulation composite material, potentially applicable in the field of modern construction, has been developed. Experimental samples based on foam glass aggregate (made from recycled waste glass), perlite (with fraction size up to 3 mm) and hydraulic binders were obtained. The acoustic and mechanical characteristics and the thermal conductivity coefficient of the prepared series of composite samples were studied. Values for Rw in the range from 38 to 46 dB and for λ from 0.04 to 0.15 W m-1 K-1 were established. The influence of the different components of the composition on the values of the studied performance indicators and the structure of the composite was analysed.

Autonomous ecologies of construction: Collaborative modular robotic material eco-systems with deep multi-agent reinforcement learning

To address the unprecedented challenges of construction pressurized by the global climate crisis, housing shortage, and growing shortage of skilled labor, this research presents a radical shift in the construction lifecycle of buildings, from linear processes that produce static continuous buildings to interrelational processes linking adaptative eco-systems of collaborative robots and reconfigurable building parts. Inspired by natural builders, the interdisciplinary field of collective robotic construction (CRC) offers the potential for scalable, adaptive, and resilient construction with simple robots. We establish a design framework for autonomous collaborative robotic construction (ACRC) through modular robotic material eco-systems (MRMES) trained with deep multi-agent reinforcement learning (DMARL). This involves the integration of three core aspects: (1) modular robotic material eco-systems (2) cyber-physical simulation and control with bidirectional feedback (3) adaptive intelligence through deep multi-agent reinforcement learning. The framework is implemented through three comparable case studies for collaborative modular robotic assembly of reconfigurable building parts.

Optimisation and Composition of the Recycled Cold Mix with a High Content of Waste Materials

This research focuses on a mineral–cement mixture containing bitumen emulsion, designed for cold recycling procedures, the formulation of which includes 80% (m/m) of waste material. Deep cold recycling technology from the MCE mixture guarantees the implementation of a sustainable development policy in the field of road construction. The utilised waste materials include 50% (m/m) reclaimed asphalt pavement (RAP) from damaged asphalt layers and 30% (m/m) recycled aggregate (RA) sourced from the substructure. In order to assess the possibility of using a significant amount of waste materials in the composition of the mineral–cement–emulsion (MCE) mixture, it is necessary to optimise the MCE mix. Optimisation was carried out with respect to the quantity and type of binding agents, such as Portland cement (CEM), bitumen emulsion (EMU), and redispersible polymer powder (RPP). The examination of the impact of the binding agents on the physico-mechanical characteristics of the MCE blend was performed using a Box–Behnken trivalent fractional design. This method has not been used before to optimise MCE mixture composition. This is a novelty in predicting MCE mixture properties. Examinations of the physical properties, mechanical properties, resistance to the effects of climatic factors, and stiffness modulus were conducted on Marshall samples prepared in laboratory settings. Mathematical models determining the variability of the attributes under analysis in correlation with the quantity of the binding agents were determined for the properties under investigation. The MCE mixture composition was optimised through the acquired mathematical models describing the physico-mechanical characteristics, resistance to climatic factors, and rigidity modulus. The optimisation was carried out through the generalised utility function UIII. The optimisation resulted in indicating the proportional percentages of the binders, enabling the assurance of the required properties of the cold recycled mix while utilising the maximum quantity of waste materials.

Snow Resource Reutilization: Design of Snow Collection and Compression Equipment Based on Functional Analysis Method

High-latitude regions of the Earth are rich in natural snow resources; however, owing to their negative impact on daily life, they have not been effectively utilized for a long time and are instead viewed as obstacles that require substantial resources for clearance. This waste of resources contradicts the principles of sustainable development. With the rapid development of the ice and snow industry, the social and economic value of snow resources is gradually becoming apparent. Therefore, to promote sustainable social and economic development, this study explores new methods for processing snow resources to achieve their recycling and high-value transformation. This study employs the functional analysis method to analyze and solve the functions of the design system, utilizing the Analytic Hierarchy Process (AHP) and fuzzy comprehensive evaluation for the objective assessment and selection of schemes. The obtained relative optimal principles are utilized to guide the parameter setting and innovative design of the scheme in terms of functional structure. After the final scheme is output, its feasibility is verified through finite element simulation. Ultimately, to address the issue of snow resource clearing and recycling, this study designs a product scheme capable of collecting and compressing snow on road surfaces, proposing the use of snow in the form of standardized compressed snow blocks for large-scale snow sculpture construction and other fields. This method significantly reduces the cost of snow sculpture production, enhances efficiency, realizes the comprehensive utilization and high-value transformation of snow resources, and provides a reference for the sustainable development of the low-altitude ice and snow tourism industry.

Coupled reactions in the system SrO–BaO–Al2O3–SiO2

Progress in the field of aircraft construction is usually determined by the functional capabilities of those materials that are used for the creation of aircraft equipment. Compositions of celsian-slawsonite ceramics belonging to the BaO–SrO–Al2O3–SiO2 oxide system are promising for use in the aircraft industry due to their high operational properties. In this regard, a theoretical study of its subsolidus structure is of great interest. The paper presents the results of calculating the Gibbs free energy for coupled reactions in the selected multicomponent system. The temperature intervals of the coexistence of phase combinations are given and the formed elementary tetrahedra are constructed. According to the results of theoretical studies, it is established that the considered multicomponent system is divided into 28 elementary tetrahedra. The existence of a combination of Sr2Al2SiO7–2SrSiO3–BaSiO3 phases in the temperature range of 300–700 K is confirmed, a "filled triangle" being formed between them. Based on the results of thermodynamic calculations, it is established that the reaction between Ba2SiO4 and SrAl2Si2O8 phases does not occur at temperatures up to 1200 K, and it is thermodynamically possible in the range of 1200–1700 K with the formation of a combination of BaSiO3–BaAl2O4–Sr2Al2SiO7 phases, which form a "filled circuit".

Comparative analysis of Environmental Impact of Each Building Material using Life Cycle assessment(LCA)_Focusing on Types of Construction Wood and Concrete

Objectives:The construction sector is a very important sector in achieving carbon neutrality. In modern society, construction has grown rapidly, and basic materials such as cement and concrete have contributed greatly to the development of construction. These materials emit a large amount of global warming substances during the raw material extraction and production process, causing serious environmental pollution. In order to establish a carbon reduction strategy to slow down global warming, we compared the environmental impacts of each building material and showed the current situation.Methods:The LCI DB for the construction materials used in the two-story wooden house (Building area 128.67m2, total floor area 235.73m2) located in the National Institute of Forest Science was extracted. Then, the data for LCA was processed and performed through the life cycle assessment methodology for the resources consumed from raw material collection, material production, and transportation stages. Then, based on the environmental performance labeling impact assessment method, a study was conducted on the environmental impact categories of the actual construction materials used and comparisons with other construction materials.Results and Discussion:When analyzing the environmental impact of concrete [25-21-120] and construction wood used in wooden house, the environmental impact was found to be 98.79% higher on average in the pre-manufacturing stage than in the manufacturing stage, and construction wood was confirmed to have a reduction effect of 62.21 kg CO2-eq per 1 m3 compared to concrete. Through the scenario, there was a carbon reduction effect of up to 36% when the entire area was replaced with wood. In addition, the environmental impact by major construction material was quantitatively quantified.Conclusion:When building a wooden house, reducing the amount of concrete equivalent to the amount of wood is expected to have a greenhouse gas reduction effect, so it is time to activate construction wood from the production process to the post-production stage to replace concrete. In addition, follow-up research on the development of construction technology with low environmental impact during construction should be continued. This study is expected to be used as a useful indicator for R&D and policies in the construction field in the future, as it quantitatively quantified the amount of CO2 reduction per m3 when replacing concrete with construction wood and numerically compared and analyzed six major environmental impact categories by major construction materials.

INFLUENCE OF FILLER SIZE ON THE STRUCTURE AND PROPERTIES OF THE POLYMER MATRIX

Purpose. The aim of the study is to investigate the influence of aluminum oxide (Al2O3) particle size on the mechanical properties of a polymer composite with added chopped glass fiber, as well as to explore the interaction between aluminum oxide particles and chopped glass fiber. Research methods. Specimens were tested for tensile strength according to DSTU EN ISO 527-5:2018. Testing was conducted using an MTS Criterion Model 43 universal testing machine with a maximum load of 50 kN. Metallographic analysis was performed using a KEYENCE VHX microscope at magnifications of 50× and 500×. The microstructure of the polymer matrix was determined on unetched samples. Scanning electron microscopy was carried out using a JEOL JSM-5510LV microscope. Results. The influence of introducing different sizes of aluminum oxide fraction on the polymer matrix was studied. It was found that with an increase in the fraction size, the strength of the polymer composition decreases. Additionally, the interaction between chopped glass fiber and various fractions of aluminum oxide on the mechanical characteristics and morphology of the connection with the polymer composition was investigated. Scientific novelty. The interaction of chopped fiber with aluminum oxide fractions may affect the mechanical properties of the composite, such as strength, stiffness, and elasticity. Investigation of the morphology of the connection between chopped fiber and aluminum oxide fractions can help understand how they interact within the composite structure. This includes analyzing the adhesion between components, the structure of junctions, and possible defects that may arise during the manufacturing process. Studying this interaction opens up opportunities for the development of new composite materials with improved properties and diverse applications in industry, construction, aviation, automotive, and other fields. Practical value. The practical significance lies in refining manufacturing technologies and implementing new materials in industry. The ability to control the mechanical properties of composites by changing the size of aluminum oxide fractions can contribute to the creation of more efficient materials for the production of automobiles, aircraft, building constructions, and more. Additionally, understanding the interaction between chopped glass fiber and aluminum oxide fractions may open up new possibilities for developing composites with unique mechanical characteristics that meet the requirements of modern technologies and industrial production.

Development of a concept of combined project-production activities planning using digital twins

The object of the study is the project-production activity of project-oriented enterprises in the fields of mechanical engineering, aircraft construction, shipbuilding, instrumentation, and metallurgy. The problem addressed was the informational integration and synchronization of project management processes, implemented by a specific project-oriented enterprise, with the management of its production processes using digital twins. The solution to this problem is aimed at improving the efficiency of project-production management by utilizing digital twins of projects and production in the planning process. The influence of trends on the development of digital technologies was analysed. The need to consider both project and operational activities of enterprises in mechanical engineering, aircraft construction, shipbuilding, instrumentation, and metallurgy as a single project-production activity was identified. It was shown that this approach can be successful when processes and changes in project-production activity can be modelled, forming a rational plan for product release and project execution. The use of digital twins for objects and processes in project-production activities was proposed. The aim and objectives of the study were formulated, focusing on the creation of a concept for planning project-production activities using digital twins for objects and processes in both project and operational activities. The concept defines the structure of the digital environment for project-oriented production, a model of the interpenetration of project and production planning processes, an aggregated critical path method, and simulation modelling for planning project-production activities using digital twins. It was shown that to model project-production activities, models and methods for managing the interaction between the operational and project processes of the company must be applied. It was proposed to use the scientific and practical tools of information interaction theory to manage this interaction. The results of applying the concept in project-oriented companies were demonstrated. The use of tools created based on the proposed concept allowed a reduction in project execution time by 10–15 % and a decrease in production costs by 5–10 % due to effective planning of project-production processes The object of the study is the project-production activity of project-oriented enterprises in the fields of mechanical engineering, aircraft construction, shipbuilding, instrumentation, and metallurgy. The problem addressed was the informational integration and synchronization of project management processes, implemented by a specific project-oriented enterprise, with the management of its production processes using digital twins. The solution to this problem is aimed at improving the efficiency of project-production management by utilizing digital twins of projects and production in the planning process. The influence of trends on the development of digital technologies was analysed. The need to consider both project and operational activities of enterprises in mechanical engineering, aircraft construction, shipbuilding, instrumentation, and metallurgy as a single project-production activity was identified. It was shown that this approach can be successful when processes and changes in project-production activity can be modelled, forming a rational plan for product release and project execution. The use of digital twins for objects and processes in project-production activities was proposed. The aim and objectives of the study were formulated, focusing on the creation of a concept for planning project-production activities using digital twins for objects and processes in both project and operational activities. The concept defines the structure of the digital environment for project-oriented production, a model of the interpenetration of project and production planning processes, an aggregated critical path method, and simulation modelling for planning project-production activities using digital twins. It was shown that to model project-production activities, models and methods for managing the interaction between the operational and project processes of the company must be applied. It was proposed to use the scientific and practical tools of information interaction theory to manage this interaction. The results of applying the concept in project-oriented companies were demonstrated. The use of tools created based on the proposed concept allowed a reduction in project execution time by 10–15 % and a decrease in production costs by 5–10 % due to effective planning of project-production processes

Experimental investigation on tailoring compressive properties and energy absorption of 3D printed gradient star re-entrant hybrid auxetic structure

Purpose Fused filament fabrication (FFF) is a widely used 3D printing technique for the fabrication of mechanical metamaterials with intricate geometries. Gradient strategy is applied to geometric parameters of gradient star re-entrant hybrid auxetic (GSRA) structure. Deformation behaviour is studied under compressive loading. The purpose of this study is to investigate the influence of gradient geometric parameters on mechanical properties, namely, specific strength (SS), specific modulus (SM) and specific energy absorption (SEA). Design/methodology/approach Response surface methodology (RSM) is implemented for the design of experiments of gradient geometric parameters to minimize the number of experimental tests. Acrylonitrile butadiene styrene material is used for the fabrication of GSRA structures by FFF technique. The best set of gradient parameters has been optimized maximizing all three responses using RSM and artificial neural network optimization technique. Findings During compressive testing, row-wise deformation is observed with two-stage plateau regions, which results in increase in SEA of the structure. Furthermore, based on analysis of variance and 3D response plots, it is found that height gradient is the most influencing gradient geometric parameter on SS and SM, whereas the wall thickness gradient has maximum influence on SEA. Meanwhile, the interaction effect of wall thickness gradient and height gradient has maximum influence on SS, SM and SEA. Research limitations/implications This study of applying gradient strategy to geometric parameters is limited to GSRA structure under compressive loading. In addition, findings are valid within the selected range of gradient geometric parameters. These findings are useful for the selection of gradient geometric parameters to maximize SS, SM and SEA of GSRA structure simultaneously. These outcomes pave the way for designing light-weight gradient hybrid auxetic structures in the field of construction, aerospace, automobile and biomedical engineering. Originality/value Limited experimental study is available on investigating the influence of gradient geometric parameters on mechanical properties, namely, SS, SM and SEA, and deformation behaviours of hybrid auxetic structures. This study directly addresses the above research gaps.

Impact of Carbon Tax on Renewable Energy Development and Environmental–Economic Synergies

Global warming caused by greenhouse gas emissions has become a worldwide environmental problem, posing a great threat to human survival. As the world’s largest emitter of carbon dioxide, China has pledged to reach peak carbon emissions by no later than 2030 and carbon neutrality by 2060. It is found that a carbon tax is a powerful incentive to reduce carbon emissions and promote an energy revolution, but it may have negative socio-economic impacts. Therefore, based on China’s 2020 input–output table, this paper systematically investigates the impacts of a carbon tax on China’s economy, carbon emissions, and energy by applying a computable general equilibrium model to determine the ideal equilibrium between socio-economic and environmental objectives. Based on energy use characteristics, we subdivided the energy sector into five major sectors: coal, oil, natural gas, thermal power generation, and clean power. The results show that when the carbon emission reduction target is less than 15%, that is, when the equilibrium carbon tax price is less than 54 yuan/ton, the implementation of a carbon tax policy can significantly reduce carbon emission and fossil fuel energy consumption, while only slightly reducing economic growth rate, and can achieve the double dividend of environment and economy. Moreover, because the reduction of coal consumption has the greatest impact on reducing carbon emissions, the ad valorem tax rate on coal after the carbon tax is imposed is the highest because coal has the highest carbon emission coefficient among fossil fuels. In addition, as an emerging clean energy source, hydrogen energy is the ideal energy storage medium for achieving clean power generation in power systems. If hydrogen energy can be vigorously developed, it is expected to greatly accelerate the deep decarbonization of power, industry, transportation, construction, and other fields.

Technological Aspects of using 3D Printing Software in Construction

The relevance of introducing additive technologies of 3D printing in construction is to decrease the technological cycle of construction, and minimize expenditure and material costs, while reducing the duration of the development planning process and execution, eliminating inaccuracies and defects, as well as optimizing and automate the process. The technological aspect of 3D printing lies in the optimal selection of parameters based on the created 3D model using effective software. The purpose of the study is to determine the quality indicators of bricks obtained by 3D printing from special concrete. The approach to investigating this matter is rooted in ascertaining the compressive strength of concrete through non-invasive testing techniques, gauging the density of concrete using measurement methods, and validating the efficacy of integrating 3D printing technologies in construction by the method of comparative analysis. The effectiveness of introducing additive technologies of 3D printing was proven drawing upon quality indicators of concrete obtained on a 3D printer which meets all the requirements necessary for its implementation in the construction field. The selected characteristics of concrete compressive strength are fundamental to the basics of selecting a brand of concrete to be utilized in construction. The selected software demonstrated the capacity to generate flawless 3D designs. The result of the study shows a significant reduction in the number of workers involved in the construction process by 38–45%, depending on the chosen method of using 3D printing; a decrease of construction time by 33–42% when printing individual elements, blocks used in production, and by 61–72% when using a printer directly on the construction site; reduction of raw materials costs by 14–28%; as well as reduction of construction downtime by 25%. The results obtained indicate the need to develop and enhance progressive additive technologies for 3D printing in construction.

Life cycle cost analysis in investment projects – examination of case studies and risk mitigation with Monte Carlo simulation

This work focuses on life cycle cost (LCC) analysis in the German natural gas infrastructure and recommends strategies to mitigate the uncertainties and risks involved using Monte Carlo simulation (MCS). It deals with the impact of input data and predicting the future development of input data on the results of the LCC analysis and discusses MCS for risk mitigation. Seven case studies for investments in Germany’s natural gas infrastructure are analyzed. In addition to the executed case studies, a case study from a scientific journal is included. The case studies were conducted between 2005 and 2015. Evaluation with real historical input data shows that the results of an LCC analysis depend on the reliability of input data and predictions on their development. The retrospective view shows that the best options are not always identified. Therefore, the results need to be validated using risk-mitigation methods, such as MCS. The executed case studies reflect the opinions of experts. This work shows how risk is mitigated through MCS while focusing on LCC analysis in the German natural gas infrastructure; however, the proposed risk mitigation with MCS can be adopted for other investment projects comprising capital expenditure (CAPEX) and operational expenditure (OPEX), for example, in construction, machines and other fields.

Practical skills in creating and conditions of a modern endoscopy department

Accumulated many years of experience in creating workrooms and functional endoscopy departments. Due to the fact that in our practice there are a lot of different regulatory documents in the field of construction: SNiP, codes of practice, practical design guidelines, as well as medical standards: SanPiN, sanitary rules, guidelines, various recommendations and orders of the Ministry of Health of the Russian Federation, there is a huge resonance on the requirements of these documents for the creation of working conditions for flexible endoscopy of a certain profile in a medical organization. There are no standards for the development of models of a specific profile of endoscopy departments due to its widespread use in various medical practices. The development of a project for a new medical organization does not in any way concern sanitary standards, while newly built modern medical organizations are checked precisely according to sanitary standards and do not in any way concern building codes. Such an imbalance leads us to the harmonization of multi-profile documents, averaging of area requirements, engineering solutions, conditions for linking the operating requirements from the manufacturer of high-tech equipment. The creation of working groups and the development of individual planning solutions allows us to take into account all the nuances for proper operation, work out the equipment according to technical and dimensional characteristics and clearly formulate the requirements for the preparation of endoscopy workrooms.

High temperature co-processing of stainless-steel slag and red mud: Towards a selective Cr immobilization and harmless treatment

Stainless-steel slag and red mud are bulk metallurgical wastes, which are difficult to reuse due to the complex composition and high environmental risk. To realize their harmless and resource utilization, a collaborative treatment of the stainless-steel slag (AOD slag) and red mud at high temperature was proposed in this study. The influence of the stainless-steel slag to red mud ratio on spinel phase precipitation and crystallization, Cr enrichment and immobilization in the mixed slags were systematically investigated. The results demonstrated that when the stainless-steel slag to red mud ratio was 6:4, the enrichment degree of Cr in spinel phase was 94.12 wt%, and the precipitation amount of spinel reached the highest, 20.98 wt%. In this case, only small amounts of other mineral phases existed, the crystal particle size of spinel phase was larger, and the self-wrapped spinel phases were formed in the stage of cooling. The outer Cr-poor spinel could avoid the abrasion and erosion of the inner Cr-rich spinel in the subsequent physical separation process, thus reducing the risk of Cr6+ dissolution. In the toxic leaching test, the total Cr concentration leached from the mixed slag (stainless-steel slag to red mud ratio was 6:4) was far lower than the national leaching concentration limit of Cr-related ions. The Cr and Fe-rich spinel phases separated from the mixed slag of stainless-steel slag and red mud can be used as the raw material for the production of stainless steel, while the residual Cr-poor slag rich in Ca, Si and Al can be applied in the field of construction.

Driving the zero-carbon construction strategy: key barriers and enablers

PurposeIn the fast-changing field of zero-carbon construction there is a gap in understanding how zero-carbon construction strategies are experienced in practice. This paper aims to identify the key barriers and enablers to driving a zero-carbon construction strategy by industry, policymakers and educators.Design/methodology/approachThe research was conducted in two stages. The first stage used a literature review to determine thematic areas from which to develop discussion points for the second stage of the research, which gathered insights into key barriers and enablers to driving a zero-carbon construction strategy from analysing recorded discussion with industry, policymakers and educators. This study adopts a qualitative research methodological design underpinned by dialectical approach of enquiries involving 31 participants. The philosophical standpoint aligns with a constructivist participatory worldview based on multiple stakeholder perspectives. Data involving virtual and face-to-face engagement held simultaneously in Australia and India were transcribed, coded and synthesised to identify the barriers and enablers to driving zero-carbon construction strategy.FindingsThe paper identified key barriers and enablers driving zero-carbon construction strategy. Barriers included limited awareness of industry dynamics; fixed mental models of professional practice; complexities in identifying appropriate skillsets; difficulties associated with reviewing education and training models and integrating sustainable strategies at early stages of projects. Enablers included: fostering education reform and supporting frameworks and procurement strategies for developers and clients; implementing efficient building designs, construction and operationalisation of zero-carbon buildings and; utilising an industry-led integrated approach. A framework was developed to provide an illustrative view of the linkage between the research projects’ focus areas and emergent themes.Originality/valueThe paper provides zero-carbon action priorities for four significant stakeholder groups in the build environment, developers, building occupiers, educators and government. As the priorities are derived in the research from examination of current literature and analysis of stakeholder viewpoints, this paper presents a unique, realistic and timely identification of barriers and key enablers driving zero-carbon construction strategies. Methodology applied in terms of data collection involved a public discourse and a unique technology-driven collaborative approach where participants simultaneously contributed across countries and time zones in a synchronous manner across key topics related to driving the zero-carbon construction strategy.

Revealing the embrittlement phenomena after post-weld heat treatment of high-strength weld metal using high-resolution microscopy

High strength combined with sufficient toughness is a fundamental prerequisite for steel in the field of lightweight construction. Joining high-strength steels by means of welding requires the use of highly advanced filler metals and a stress-relief post-weld heat treatment (PWHT) for optimum performance of the joint. However, such a heat treatment can lead to embrittlement in the weld metal. In this context, the present work deals with the influence of different PWHT holding temperatures on the microstructure and mechanical properties of a high-strength multipass all-weld metal to reveal the embrittlement phenomena. The all-weld metal was fabricated via gas metal arc welding using a metal cored wire with a minimum yield strength of 690 MPa. Charpy V-notch impact testing and tensile testing were carried out to characterize the strength and toughness of the all-weld metal in the as-welded condition and after a 2 h stress-relief PWHT at 520 °C, 580 °C, and 620 °C. The microstructure was characterized utilizing high-resolution techniques such as atom probe tomography and high-energy X-ray diffraction. The strength and toughness of the all-weld metal both decrease after PWHT with different holding temperatures. The cause for the observed embrittlement was found to be the formation of Mn-rich cementite precipitates. These carbides increase in size and phase fraction with increasing holding temperature and lead to a brittle transcrystalline cleavage fracture. Consequently, it was concluded that a gas metal arc welded joint with the investigated filler metal should not be exposed to stress-relief PWHT at temperatures higher than 580 °C.

Digital Archives for Academic Heritage: Tools and Processing Environments for the Museum Metaverse and Scientific Dissemination

Abstract. In recent years the digital visualisation techniques, including 3D digital models of indoor spaces, saw an exponential increase in their applications, both in the fields of Architecture, Engineering and Construction (AEC) and of Cultural Heritage (CH). This growth is mainly due to the increasing affordability of tools for the acquisition and elaboration of three-dimensional digital survey/data management and to their increasing ‘user friendliness’.The research proposes a further step on research started some years ago by our group about the exploration of indoor mapping for the creation of the 3D virtual museum of our Institution, starting with the realisation of a virtual model of the university’s spaces (departments and halls). At first, the virtual museum will host the Curioni Digital Collection, which consist of circa 140 wooden models of building details, bridges, tunnels, and vaults designed by prof. G. Curioni during the second half of the XIX century as teaching aids for the Construction and Structural Design classes. A comparison between two main tools to support management and diffusion of geometrical, alphanumerical, and topological data will be given (Matterport and Unity). The parallel approach considering two tools is to provide a digital twin of a real collection placed in a real space, and, on the other hand, to use a real historical university space, virtualized, to host a virtual collection.

A Specialized Pipeline for Efficient and Reliable 3D Semantic Model Reconstruction of Buildings from Indoor Point Clouds.

Recent advances in laser scanning systems have enabled the acquisition of 3D point cloud representations of scenes, revolutionizing the fields of Architecture, Engineering, and Construction (AEC). This paper presents a novel pipeline for the automatic generation of 3D semantic models of multi-level buildings from indoor point clouds. The architectural components are extracted hierarchically. After segmenting the point clouds into potential building floors, a wall detection process is performed on each floor segment. Then, room, ground, and ceiling extraction are conducted using the walls 2D constellation obtained from the projection of the walls onto the ground plan. The identification of the openings in the walls is performed using a deep learning-based classifier that separates doors and windows from non-consistent holes. Based on the geometric and semantic information from previously detected elements, the final model is generated in IFC format. The effectiveness and reliability of the proposed pipeline are demonstrated through extensive experiments and visual inspections. The results reveal high precision and recall values in the extraction of architectural elements, ensuring the fidelity of the generated models. In addition, the pipeline's efficiency and accuracy offer valuable contributions to future advancements in point cloud processing.

Data envelopment analysis for performance measurement in the construction field: a systematic review

Data envelopment analysis for performance measurement in the construction field: a systematic review

Imaging research on damage localization of concrete structure based on Lamb wave and Bayesian fusion algorithm

Concrete structures are critical materials in the field of industrial construction and are susceptible to invisible damage under the influence of a variety of factors. The method of increasing the number of sensors is usually used to obtain high-precision damage detection, but it increases the experimental cost and signal processing time, so it is especially important to perform high-precision and low-cost non-destructive testing for it. The article uses Bayes to combine the elliptical trajectory method with a probabilistic damage imaging algorithm, and utilizes the algorithm to achieve higher accuracy damage localization imaging results with a smaller number of sensors. The wavelet transform is used to calculate the time of flight to obtain the localization results of the elliptical trajectory method, the signal damage factor is calculated based on the amplitude information to obtain the localization results of the probabilistic damage imaging, the probability distribution of the damage location is obtained using Bayesian, and the damage localization results are obtained by solving the problem through the Markov chain Monte Carlo method. A dense sensor array based and probabilistic imaging algorithm is also used to localize the damage to the material and the results are compared with the results of the Bayesian fusion algorithm. The results show that the Bayesian fusion algorithm can obtain higher accuracy of damage localization with a significant reduction in the number of sensors, and at the same time greatly reduces the number of signals, simplifies the experimental process, and has high practical value.