Construction Process Research Articles

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.

A Review of the Utilization of Recycled Powder from Concrete Waste as a Cement Partial Replacement in Cement-Based Materials: Fundamental Properties and Activation Methods

Recycled powder (RP) is the primary by-product generated during the reclamation process of construction and demolition waste (CDW). There is existing literature on the use of RP as supplemental cementitious materials (SCMs) in cement-based materials, but a comprehensive evaluation on the characteristics of RP generated from concrete waste has been missing until now. This paper critically reviews the use of RP from concrete waste in cement-based materials, as concrete waste makes up a significant amount of CDW and other components have designated recycling methods. In this sense, this study conducted a critical analysis on the use of RP as an SCM, using detailed literature research. The technology used for producing RP is detailed along with its chemical, mineralogy, and microstructural characteristics. Fresh-state properties in cementitious matrices with RP are introduced with the view of mechanical grinding, thermal activation, carbonation, chemical treatment, biomineralization, mineral addition, nano activation, and carbonation. The review highlights the significant potential of utilizing RP in cement-based materials. Specifically, RP can be advantageously utilized in the production of value-added construction materials.

Recent Advances in Multifaceted Drug Delivery Using Natural Polysaccharides and Polyacrylamide-Based Nanomaterials in Nanoformulation.

Rapid growth in nanotechnology, also known as 21st-century technology, is occurring in response to the increasing diversity of diseases. The development of safe and effective drug delivery methods to enhance bioavailability is of paramount importance. Researchers have focused on creating safe, cost-effective, and environmentally friendly nanoparticle construction processes. Natural polysaccharides, a type of multifaceted polymer with a wide range of applications and advantages, are particularly well suited for nanoparticle formulations, as they can mitigate the adverse consequences of synthetic nanoparticle formulations and promote sustainability. This review summarizes various sources of natural-based polysaccharides and polyacrylamide-based nanomaterials in nanoparticle preparation. Additionally, it discusses the use of natural polysaccharides in formulations beyond nanotechnology, highlighting their importance in green synthesis and different preparation methods.

METODOLOGIA BIM NA GRADUAÇÃO DE ARQUITETURA E URBANISMO: UMA ANÁLISE DAS MATRIZES CURRICULARES DAS INSTITUIÇÕES PRESENCIAIS DE VITÓRIA DA CONQUISTA – BA

This study addresses the importance of introducing the BIM (Building Information Modeling) methodology into the Architecture and Urbanism undergraduate curriculum, considering the continuous transformations in the construction sector. Given the growing need for adaptation to new market demands, it is essential that future architects are qualified to integrate practices that promote greater agility and efficiency in project development. The research adopts a qualitative approach, using bibliographic, to demonstrate the relevance of teaching BIM from the academic stage. The study highlights how this innovative methodology not only prepares students for professional challenges but also significantly enhances their performance in the job market. The inclusion of BIM in the educational environment is identified as a competitive advantage, allowing for a deeper understanding of the design and execution phases, as well as fostering more efficient integration between the various actors involved in the construction process. Thus, this study reinforces the need for curricular reform that incorporates BIM as an essential component of the training of architects and urban planners.

The role of reflection in learner identity construction. A sociocultural and dialogical approach / El papel de la reflexión en el proceso de construcción de la identidad de aprendiz. Una aproximación sociocultural y dialógica

The purpose of this article is to present a theoretical-conceptual proposal that enables us to articulate two psychological processes that play an essential role in different educational settings yet are seldom explicitly addressed together: identity construction and reflection processes. Specifically, we will analyse the way reflection is a prime tool for reconstructing learner identity. In the first part, we conceptualize reflection processes from a sociocultural and dialogical approach. In the second part, we explain our theoretical approach to identity construction processes, define the concept of learner identity and highlight the role played by reflection in identity construction. To conclude, we will suggest several guidelines for promoting student reflection on their own learning processes and on themselves as learners with the goal of facilitating their development of an enabling learner identity that allows them to continue learning in different settings and times in their lives.

Environmental tradeoff on integrated carbon capture and in-situ methanation technology

Compared to conventional CO2 removal methods, carbon capture and in-situ conversion using dual function materials avoid compression and transportation of CO2, which is regarded as a promising technology. Although it brings additional economic benefits, the environmental impacts of CO2 capture and conversion remain unclear. A life cycle assessment of an integrated CO2 capture and methanation system using dual function materials is conducted to investigate its feasibility to reduce global warming. Life cycle inventory is obtained through construction, operation, and disposal process of the integrated system. A dynamic model of CO2 capture and methanation is developed to obtain the operating parameters. Results show that the optimal global warming potential is 0.706 kg CO2,eq per kilogram captured CO2, which indicates the advantages of using dual function materials for carbon mitigation. Global warming potential is a minor factor among the overall normalized environmental impacts, only accounting for 0.5 % of the total normalized impact, while the main factor marine aquatic ecotoxicity accounts for around 73 %, and fresh water aquatic ecotoxicity accounts for around 23 %. Global warming potential is the most affected by green hydrogen input, followed by dual function material input. Results reveal that the integrated CO2 capture and conversion using dual function materials is conducive to carbon mitigation but has significant other environmental impacts, such as marine aquatic ecotoxicity, and the main contributors to the environmental impacts are wind electricity, green hydrogen, refrigerator, and dual function material.

Test-retest reliability and construct validity of Inosen’s Silat Momentum Test

Problem Statements: The kick in Pencak Silat has a magnitude called momentum, which requires a tool capable of measuring several variables based on the International System of Units (SI) in real-time. Nowadays, there are affordable and reliable sensor technologies to meet these needs. Purpose: The research aimed to design a test instrument that utilizes sensor technology to measure kick momentum in the sparring category of Pencak Silat following the applicable SI, and to test its reliability and validity. The resulting instrument is named Inosen’s Silat Momentum Test. Approach: This study followed Johnson and Nelson’s seven-test construction process. Twenty-four Pencak Silat athletes, consisting of 12 elite and 12 non-elite participants, were involved in the evaluation process. The test’s reliability was assessed by examining the correlation between the test and retest results. The construct validity test was conducted by comparing the results of the front kick tests of elite and non-elite Pencak Silat athletes. Data analysis was performed using Pearson correlation and independent t-tests using Minitab 21.4.1 software. Results: The results of the test and retest indicate a very high correlation (r = 0.923), demonstrating the consistent ability of Inosen’s Silat Momentum Test to measure kick momentum. The study found a statistically significant difference in the Inosen’s Silat Momentum Test scores (p < 0.05) between the elite fighter group (average score of 463.3 kg.m/s) and the non-elite fighter group (average score of 375 kg.m/s). The results indicate that Inosen’s Silat Momentum Test is an effective instrument for differentiating kick momentum based on fighter performance. Conclusions: Based on the findings, it is inferred that Inosen’s Silat Momentum Test is a reliable and valid instrument for measuring Pencak Silat kick momentum according to SI standards. Keywords: biomechanics, kick momentum, pencak silat, performance test, sensor technology.

Dynamics of the construction of agency and identity during the transition from primary to secondary school in students in Colombia / Dinámicas de construcción de agencialidad e identidad durante la transición de la primaria a la secundaria en estudiantes en Colombia

This study analyses the dynamics of the construction of agency and identity in one boy and one girl during the transitional period between primary and secondary school and the time when they embark on adolescence in a school in Colombia. Drawing from the principles of Grounded Theory, interviews and observations were conducted. The analysis applied a thematic and microgenetic analysis to identify issues in tension, functions, directions of change and dynamics of reflexivity and agency. The results showed a transformation of meanings and positionings in reflexivity on belonging to or being part of a social group at school, which mobilized the development of agency for both identifying and differentiating oneself. The agency<>reflexivity dynamics were articulated in identity construction processes in the midst of the challenges of school transitions and development. We discuss the findings and their implications in terms of changes and transformations to construct maps of agency development, as well as the possible discussions around the traditional Kantian educational models.

Travel influencers and their social identity: a phenomenological approach

ABSTRACT The role of travel influencers has become increasingly popular, having a significant impact on tourists and tourism businesses. Influencers negotiate and navigate challenges such as content quality and authenticity while fostering a sense of community and influencing industry standards. Little is known, however, about how travel influencers construct their social identities. Based on social identity theory, and by interviewing 19 Chinese travel influencers, this study developed the following three-stage representation of travel influencer social identity construction: ‘transformation’, ‘maintenance’, and ‘identity value presentation’. It makes significant contributions to extant tourism literature by providing unique insights into the construction process associated with the identities of travel influencers.

Design and preparation of composite bipolar plates with synergistic conductive networks of graphite and metal foam

Graphite composite bipolar plate (BP) have limited conductivity, which makes them less than ideal for extensive application in proton exchange membrane fuel cell (PEMFC). In traditional graphite composite BP, the construction process of the conductive network is entirely random. To enhance conductivity, it is typically necessary to increase the content of conductive fillers or incorporate high aspect ratio carbon nanomaterials to optimize the density of the conductive network. In this work, we manufactured a highly conductive composite bipolar plate with synergistic conductive networks of graphite and metal foam (MF). With a synergistic conductive network, the ASR of CuG80-20ppi decreased to 7.7 mΩ cm2. Additionally, thermal conductivity increased to 24.76 W/(m·K), and in-plane conductivity reached 294.1 S/cm at 80 wt% mass fractions of conductive filler, using 20 ppi copper foam as the metallic conductive network. CuG80-20ppi exhibited a flexural strength of 52.2 MPa. G80 and CuG80-20ppi have the 80 wt% conductive filler and are molded into BP with parallel flow fields. CuG80-20ppi enhances the current density of PEMFC by 0.132 W/cm2 and reduces the ohmic impedance by 5.25%. Therefore, the findings of this study offer valuable insights for the enhancement of composite BP conductivity, while simultaneously ensuring the stability and continuity of the synergistic conductive network. A novel approach is presented to enhance the electrical conductivity of graphite composite bipolar plate (BP) for proton exchange membrane fuel cells (PEMFCs). By embedding metal foam as a supplementary conductive network within the graphite matrix, a synergistic conductive architecture is achieved. This innovation significantly reduces the area specific resistance (ASR) to 7.7 mΩ cm2 and boosts thermal conductivity to 24.76 W/(m·K). The resulting CuG80-20ppi BP, with 80 wt% conductive filler, exhibits improved mechanical strength and conductivity, contributing to a 0.132 W/cm2 increase in PEMFC current density and a 5.25% reduction in ohmic impedance. This work highlights the potential of metal foam integration to enhance BP conductivity and PEMFC performance.

Analysis of the Construction Sequence of a Reaction Wall in a Structural Laboratory Supported by the VDC Methodology

The structures laboratory is a crucial facility for supporting research development related to the construction industry. This kind of laboratory has several components, and one of its key components is the reaction wall. The reaction wall supports the execution of experimental tests on structural elements under specific configurations and loads. Constructing a reaction wall presents challenges due to the highest standards to be met. This research analyzes the construction process of a reaction wall at a private university in Peru. Initially, a schedule was proposed by a contractor. However, the client, knowing the complexity of such construction, asked to review the initial schedule to ensure that it would meet the constructability requirements under the integrated product-organization-process approach given by the virtual design and construction (VDC) methodology. The result of this study pointed out the need to revise the original proposed schedule, extending the construction time to 66% due to the lack of construction processes compatible with the requirements for the reaction wall’s execution. Finally, a survey was conducted to observe the learning curve associated with implementing the VDC methodology.

An Easy-to-Use Arrayed Brain–Heart Chip

Multi-organ chips are effective at emulating human tissue and organ functions and at replicating the interactions among tissues and organs. An arrayed brain–heart chip was introduced whose configuration comprises open culture chambers and closed biomimetic vascular channels distributed in a horizontal pattern, separated from each other by an endothelial barrier based on fibrin matrix. A 300 μm-high and 13.2 mm-long endothelial barrier surrounded each organoid culture chamber, thereby satisfying the material transport requirements. Numerical simulations were used to analyze the construction process of fibrin barriers in order to optimize the structural design and experimental manipulation, which exhibited a high degree of correlation with experiment results. In each interconnective unit, a cerebral organoid, a cardiac organoid, and endothelial cells were co-cultured stably for a minimum of one week. The permeability of the endothelial barrier and recirculating perfusion enabled cross talk between cerebral organoids and cardiac organoids, as well as between organoids and endothelial cells. This was corroborated by the presence of cardiac troponin I (cTnI) in the cerebral organoid culture chamber and the observation of cerebral organoid and endothelial cells invading the fibrin matrix after one week of co-culture. The arrayed chip was simple to manipulate, clearly visible under a microscope, and compatible with automated pipetting devices, and therefore had significant potential for application.

A construction contract administration (CCA) framework for graduate architects’ professional development

PurposeConstruction contract administration should be carried out by a person (normally engineer or architect depending on the type of contract) with expert technical knowledge of the construction process, strong leadership quality, highly developed interpersonal skills and an understanding of contractual, legislative and statutory underpinnings. However, due to a shortage of architects, graduate architects have been assigned to perform a partial role. Architectural firms are disappointed with the quality of the graduates and still note that they have to mentor them to be competent for their jobs. This paper aims to develop a construction contract administration (CCA) framework for graduate architects that aids the smooth running of a construction contract.Design/methodology/approachSeven housing projects in Malaysia have been selected as case studies. Documentation review and semi-structured interviews relevant to selected case studies were conducted to collect data to develop the CCA framework. The draft framework will then be validated through a focus group study.FindingsA total of 5 themes and 11 sub-themes with core tasks were developed in the CCA framework. The themes involved are claims and legal matters management, communication and relationship management, project management, design management and quality assessment and management. Sub-themes are authority matters, building certification, meetings, coordination checklist, letter writing, contract documentation, building material, design brief, building sustainability and workmanship quality standards, contractors’ submission and building details.Originality/valueThe contribution of this study can be utilized for developing further models in the future that would improve the work performance of graduate architects. The framework assists the university by moving forward to the professional practice stage. In addition, it indirectly enhances the potential of graduate architects to perform efficiently and intensifies the bonding between project stakeholders.

Internally-consistent and fully-unbiased multimodal MRI brain template construction from UK Biobank: Oxford-MM

Abstract Anatomical MRI templates of the brain are essential to group-level analyses and image processing pipelines, as they provide a reference space for spatial normalisation. While it has become common for studies to acquire multimodal MRI data, many templates are still limited to one type of modality, usually either scalar or tensor-based. Aligning each modality in isolation does not take full advantage of the available complementary information, such as strong contrast between tissue types in structural images, or axonal organisation in the white matter in diffusion tensor images. Most existing strategies for multimodal template construction either do not use all modalities of interest to inform the template construction process, or do not use them in a unified framework. Here, we present multimodal, cross-sectional templates constructed from UK Biobank data: the OMM-1 template, and age-dependent templates for each year of life between 45 to 81. All templates are fully unbiased to represent the average shape of the populations they were constructed from, and internally consistent through jointly informing the template construction process with T1, T2-FLAIR and DTI data. The OMM-1 template was constructed with a multi-resolution, iterative approach using 240 individuals in the 50-55 year age range. The age-dependent templates were estimated using a Gaussian Process, which describes the change in average brain shape with age in 37,330 individuals. All templates show excellent contrast and alignment within and between modalities. The global brain shape and size is not preconditioned on existing templates, although maximal possible compatibility with MNI-152 space was maintained through rigid alignment. We showed benefits in registration accuracy across two datasets (UK Biobank and HCP), when using the OMM-1 as the template compared with FSL’s MNI-152 template, and found that the use of age-dependent templates further improved accuracy to a small but detectable extent. All templates are publicly available and can be used as a new reference space for uni- or multimodal spatial alignment.

Beam Local Stress Prediction Model for Incremental Launching Construction Based on SSA-SVR Algorithm

In the multi-point incremental launching construction process, without setting temporary piers at the mid-span, it is difficult to ensure the synchronization of the launching equipment at the same pier, which can easily cause the beam to deviate from the design axis, leading to changes in the stress of the beam. Calculating the local maximum stress of the beam when lateral deviation occurs is beneficial for establishing a reasonable and reliable threshold for controlling beam deviations. To address this issue, this paper utilizes a finite element model of the bridge under typical adverse conditions, simulating the lateral deviation and asynchronous jacking of the beam to explore stress variation patterns. The results show that the beam stress increases as the lateral deviation and jacking differences increase, severely affecting the structural safety. To overcome the inefficiency of the finite element modeling method when dealing with multiple working conditions and to establish a reasonable deviation control threshold, this study proposes a beam local stress prediction model under the combined influence of lateral deviation and jacking height differences based on the SSA-SVR algorithm. The model calculates the local maximum stress of the beam for 2500 sets of parameters. An engineering case analysis shows that the prediction model has high calculation accuracy, reliable results, fast computational speed, and high efficiency. Based on the stress prediction results, it is recommended to set the jacking height difference control threshold at 20 mm. When the jacking height difference is less than 20 mm, the local maximum stress value under the combined influence of both parameters should be less than the standard limit. The corresponding lateral deviation control threshold can be dynamically adjusted according to the actual travel difference recorded by the jacking equipment, with the control precision improved to 1 mm.

Methods to Stimulate the Proactivity of Enterprises in Fulfilling Safety Responsibilities: A Fundamental Issue in Construction Safety Management

Management factors are among the most significant causes of construction safety incidents, and there is an issue of insufficient supervision at present. The degree of diligence exhibited by relevant entities is crucial, and the payoff can influence the decision-making behaviors of involved parties. Based on this, the aim of this paper is to investigate how to enhance the initiative of enterprises in fulfilling their safety responsibilities during the construction process. By developing a tripartite evolutionary game model that involves supervision companies, general contractors, and labor subcontractors and conducting numerical simulation analysis, we reveal that simultaneous proactive investment in safety by all three parties is challenging, with labor subcontractors being relatively more prone to opt for active safety investment. Supervision companies and general contractors often struggle to fulfill their safety duties at the same time. Factors such as the rewards and penalties stipulated in a contract, rent-seeking amounts, and accident-related losses have a significant impact on the evolution of the system. Based on the findings, we propose recommendations for construction management, which include the management of labor subcontracting in construction, the control of rent-seeking behaviors, and the establishment of a cooperative safety culture during the construction process.

Biofuser: a multi-source data fusion platform for fusing the data of fermentation process devices.

In the past decade, the progress of traditional bioprocess optimization technique has lagged far behind the rapid development of synthetic biology, which has hindered the industrialization process of synthetic biology achievements. Recently, more and more advanced equipment and sensors have been applied for bioprocess online inspection to improve the understanding and optimization efficiency of the process. This has resulted in large amounts of process data from various sources with different communication protocols and data formats, requiring the development of techniques for integration and fusion of these heterogeneous data. Here we describe a multi-source fusion platform (Biofuser) that is designed to collect and process multi-source heterogeneous data. Biofuser integrates various data to a unique format that facilitates data visualization, further analysis, model construction, and automatic process control. Moreover, Biofuser also provides additional APIs that support machine learning or deep learning using the integrated data. We illustrate the application of Biofuser with a case study on riboflavin fermentation process development, demonstrating its ability in device faulty identification, critical process factor identification, and bioprocess prediction. Biofuser has the potential to significantly enhance the development of fermentation optimization techniques and is expected to become an important infrastructure for artificial intelligent integration into bioprocess optimization, thereby promoting the development of intelligent biomanufacturing.

Addressing diversity in flux: identity work, identity negotiation and intersectionality insights

PurposeDiversity management literature is at a crossroads with limitations in producing novel insights due to its heavy reliance on the etic approach and surface-level diversity. This paper reviews identity work, identity negotiation and intersectionality to propose an interdisciplinary lens that offers new insights and suggestions for future research that will advance the diversity management literature.Design/methodology/approachOur paper advances methods in the diversity management literature by reviewing interdisciplinary research using a dual approach: a bibliometric analysis of the vast literature examining 323 papers published between 1987 and 2023, supplemented by a summary review of the identified thematic clusters.FindingsThis study identified seven thematic clusters around identity construction, transformation and navigation processes. The study highlights significant research gaps in (1) context-specificity, (2) deep-level forms of diversity, (3) lack of focus on meso-level stakeholders, and most importantly (4) lack of focus on the interplay of micro-level and meso-level interactions.Originality/valueThis paper contributes in three ways. Firstly, it pioneers a dual approach to comprehending the research landscape on identity work, identity negotiation and intersectionality, employing bibliometric analysis and summary review. Secondly, with its interdisciplinary reach, it advocates for a more inclusive diversity management approach, exploring micro-meso-level interaction through new lenses. Lastly, it offers theoretical and practical contributions by proposing an integrated multiple lens to better address the challenges and tensions of an increasing diversity of the workforce.

An improved generalized flexibility matrix-based damage identification technique for derrick steel structures

An improved generalized flexibility matrix-based method using matrix partitioning technique for structure damage identification is proposed. As an effective damage identification method, the generalized flexibility matrix requires fewer vibration frequencies and corresponding modal shapes compared with the traditional flexibility matrix method. By introducing a new partitioning technique of the matrices involved in the constructive process of the governing equation, the improved method simplifies the process of calculation with a dramatic reduction in computational cost while maintaining accuracy of identification results. In the case of incomplete measured modal data, an improved matrix partitioning technique based on the model expansion method is applied and the damaged indicators can be identified using partial measured modal data. A K-type derrick steel structure in service is considered as a numerical example for inspection the validity and feasibility of the proposed method. Numerical results show better accuracy and efficiency of this method for various damage scenarios, and can be used for damage diagnosis or health monitoring of other large structures.

Experimental study on the factors affecting cement bond strength at the second interface of oil-gas well

The second interface of cementing refers to the interface formed by the formation and the cement sheath after cementing. The bonding strength of the second cementing interface is mainly generated through the interaction between the cement sheath and the formation. This study employs sandstone and limestone as experimental materials to investigate the influencing factors on the bonding strength of the second cementing interface by altering the water-cement ratio of the cement slurry system, adding ultrafine materials, and incorporating latex materials. In a progressive experimental approach, various types of cement slurries are selected, including pure cement slurry systems under different water-cement ratios (L1, L2), cement slurry systems with added nano-silica on the basis of pure cement systems (L3), and cement slurry systems with latex added (L4). The influence factors of the bonding strength of the second cementing interface of cement sheaths are explored through self-developed bonding strength evaluation molds and micro-characterization of the bonding interface. The results indicate that increasing the water-cement ratio or adding nano-silica can promote the generation of calcium silicate hydrate (C-S-H), resulting in higher early bonding strength but lower later strength under sandstone interfaces; the reaction of latex particles themselves to form a three-dimensional network structure can enhance the bonding strength. This research provides significant insights into the bonding laws of the second cementing interface and is of great importance to the cementing construction process.