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1.
Heliyon ; 9(9): e19697, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37809722

ABSTRACT

The construction industry (CI) plays a vital role in infrastructure development and improves the socio-economic status with employment opportunities and contribution to gross domestic progress (GDP) of countries. However, its productivity has diminished in recent years due to increasing complexities in construction projects (CPs) and lack of adoption of novel technologies such as Building Information Modeling (BIM). Also, there is a significant need of polishing the capabilities of construction practitioners to meet the project requirements in agreement with project management knowledge areas (PMKAs). This study, therefore, focused on identification and evaluation of factors necessary for measurement of extent of application of PMKAs. Subsequently, noteworthy features of BIM helpful for enhancing the capabilities of project managers (PMs) in application of PMKAs were identified from literature. A total of thirty-three factors for measurement of extent of application of PMKAs and sixty-six features of BIM helpful in enhancing the capabilities of PMs in application of PMKAs were found. The detailed study and analysis of these ninety-nine factors with the help of previous studies suggested that extent of application of PMKAs is measured with three sub-tasks i.e., plan, manage/develop, and monitor/control. In addition, by virtue of remarkable features and services of BIM, it helps in enhancing the capabilities of PMs in applying PMKAs: project integration, scope, cost, time, quality, resource, communications, procurement, risk, safety, and stakeholder management.

2.
Int J Occup Saf Ergon ; 29(4): 1358-1367, 2023 Dec.
Article in English | MEDLINE | ID: mdl-36177998

ABSTRACT

The construction industry is one of the hazardous fields due to its exceptional environment. Therefore, this work aimed to assess the essential drivers needed for employing safety management in the Palestinian construction industry. The drivers for safety management were recognized from earlier literature, where the questionnaires were dispersed to professionals from construction projects. The exploratory factor analysis (EFA) technique was then performed to contextually adjust the identified drivers. The results showed that safety management drivers could be categorized into three constructs: management, awareness and policy. In addition, partial least squares structural equation modelling (PLS-SEM) was performed to generate the safety management driver's model. The results indicated that management drivers were vital drivers for adopting safety management. The study's findings would act as a reference for construction stakeholders to decrease danger and enhance the construction project's success via implementing safety management drivers.


Subject(s)
Construction Industry , Safety Management , Humans , Latent Class Analysis , Safety Management/methods , Employment , Surveys and Questionnaires
3.
Environ Sci Pollut Res Int ; 29(50): 75380-75401, 2022 Oct.
Article in English | MEDLINE | ID: mdl-35655017

ABSTRACT

This research aimed to investigate the effect of nanorice husk ash (NRHA) prepared using different thermal treatment methods on ultra-high-performance concrete (UHPC) behaviour. NRHA was prepared by two methods: (1) burning for 3 h at 300, 500, 700 and 900 °C and (2) burning for different durations (9, 7, 5 and 3 h) at 300, 500, 700 and 900 °C. NRHA was added to UHPC to make 25 mixtures with three dosages (1%, 3% and 5%). Density, compressive strength, tensile strength, flexure strength and ultrasonic pulse velocity tests were performed at the experimental level. Moreover, full microstructure analysis, including X-ray diffractometry, Brunauer-Emmett-Teller surface area analysis, thermogravimetric analysis, scanning electron microscopy and energy-dispersive X-ray spectroscopy, was performed. The best performances in in the first method (constant duration, different temperatures) were obtained by 1% NRHA burned at 900 °C with 12.5% compressive strength and 1% NRHA burned at 700 °C with increased ratio (10%). Moreover, the best performance in the second method (different burning durations and temperatures) was obtained by 3% NRHA with a ratio of 22.5% at 700 °C for 5 h. Burning rice husk ash improved the compressive strength. It also remarkably improved the splitting tensile strength and flexure strength by 32% and 47%, respectively, at 3% NRHA treated at 700 °C for 3 h. The microstructural analysis showed the efficient role of NRHA in the compactness of concrete sections. It improved the formation of new calcium silicate hydrate gel; decreased the cracks, voids, CaCO3 and Ca(OH)2; and increased the Ca/Si composition. The obtained experimental results were used to build an artificial neural network (ANN) to predict UHPC properties. The ANN model was used as a validation tool to determine the correlation between results. Results showed a remarkable improvement in the mechanical properties of UHPC incorporating NRHA for all mixtures. The ANN model indicated a reliable correlation between input and output variables. The R2 values for the training, validation and testing steps were all 0.99.


Subject(s)
Construction Materials , Compressive Strength , Microscopy, Electron, Scanning , Spectrometry, X-Ray Emission , Temperature
4.
Environ Sci Pollut Res Int ; 29(44): 66085-66099, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35488991

ABSTRACT

In recent years, the demand for clean water has been growing all over the world despite the different threats posed, including increasing pollution, increasing deforestation and climate change. Industrial activity is the second largest consumer of water, so highly industrialized regions are more susceptible to water stress. In this sense, reuse strategies have been progressively discussed and used around the world; however, in Brazil there is still place for many advances, whether due to lack of incentives, cultural issues in society, or poor regulation of the subject. The objective of this work was to carry out a diagnosis of raw water uptake by industries in one Hydrographic Region of the state of Rio de Janeiro and to propose a discussion on the adoption of water reuse practices for non-potable purposes from the use of treated effluents. A survey of the theoretical framework on the subject was carried out, as well as an analysis of sustainability indicators and reports of the companies, including the current licensing processes of large undertakings consuming water resources. With this study, it was possible to obtain the average cost of implementing a water reuse unit for an industry in the state of Rio de Janeiro-Brazil, which, despite still being expensive, has a strong tendency to use due to world water shortages. Finally, it was concluded that the state of Rio de Janeiro has a threat of water scarcity that could be aggravated in the coming years, if measures and investments in supply alternatives are not adopted (water reuse), and improvement in all stages of water management water resources.


Subject(s)
Rivers , Water Resources , Brazil , Industry , Water Supply
5.
Materials (Basel) ; 15(7)2022 Apr 01.
Article in English | MEDLINE | ID: mdl-35407930

ABSTRACT

The brittleness of plain concrete represents a significant issue to the integrity of concrete structures when subjected to impact loading. Recent rapid industrialization has attracted researchers to find a solution for concrete brittleness and enhance its ductility. In light of this, the prepacked aggregate fibrous concrete (PAFC) with single and double precoated coarse aggregates using asphalt is proposed and examined. Nine different mixtures were designed using polypropylene and steel fibre of 3% dosage with single and double asphalt-coated aggregates. Specimens were prepared with natural aggregate and 100% C-graded asphalt-coated aggregate to evaluate their impact strength. The ACI Committee 544 drop-weight impact standard was followed in the testing of all specimens. Results indicated that using asphalt-coated aggregate can improve the impact energies of concrete. The impact energy at cracking and failure of the single asphalt-coated aggregate specimen was 1.55 and 2.11 times higher, while the double-coated aggregate specimens exhibited 1.73 and 2.56 times greater than the natural aggregate specimen, respectively. The contribution of fibres in enhancing the impact resistance is remarkable compared to the single- and double-coated aggregates used in PAFC.

6.
Environ Sci Pollut Res Int ; 29(23): 34984-35000, 2022 May.
Article in English | MEDLINE | ID: mdl-35044607

ABSTRACT

The purpose of this study is to demonstrate the impact of incorporating two different types of green nanomaterials (sugarcane and eggshell) on destructive and non-destructive properties of mortar. Nano sugarcane (NSC) was manufactured by calcining sugarcane at temperatures of 600 °C for 3 h. On the other hand, nano eggshell (NES) was manufactured by calcining eggshell at temperatures of 600 °C for 6 h. The sugarcane ash and eggshell ash were then milled to nano size. The final nano-sized product replaced Portland cement with different dosages of 2, 4 and 6%. Sixteen mortar mixtures were designed and prepared using only NSC or only NES or a combined hybrid of NSC and NES. Consistency, compressive strength, flexural strength and microstructure analysis (scanning electron microscopy and energy-dispersive X-ray) tests were conducted to investigate the influence of replacement materials on the performance and properties of mortars. The results showed that the use of nano sugarcane and nano eggshell enhanced the compressive strength and reduced permeability of green mortar due to the micropore structure. At the ages of 7 and 28 days, mortars containing a replacement ratio of 2% (0.5% NSC + 1.5% NES) had remarkably improved mechanical properties, and the improvement in compressive strength reached 21.3% and flexural strength to 10.08% when compared to the control sample. The efficiency of NSC and NES in increasing mortar strength was also confirmed by microstructure analysis.


Subject(s)
Nanostructures , Saccharum , Animals , Compressive Strength , Construction Materials , Egg Shell , Nanostructures/chemistry
7.
Int J Occup Saf Ergon ; 28(4): 1981-1993, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34126867

ABSTRACT

Objectives. Lean construction techniques have been considered an effective approach and strategy to reduce accidents in construction projects. This article aims to investigate the application of the lean construction principle and its impact on occupational health and safety. Methods. To achieve the aim, an analytical descriptive method was used. The data were collected through a questionnaire, with 70 respondents who were chosen using a random stratified sample method. The questionnaire evaluated the perception of contractors and consultants about the important lean construction factors and their impact on construction project safety. Results. There is an agreement that the application of lean construction techniques can be impeded by challenges like lack of lean construction knowledge, complexity, misconception about lean construction and difficulties in changing employees. Conclusions. The study identified strategies that could be used to address these challenges that will improve the safety of construction projects. These include enlightenment on benefits of the lean practice, publication of improvements realized from lean practice, training, workers' involvement and empowerment, persistence, robust planning and gradual implementation.


Subject(s)
Construction Industry , Occupational Health , Humans , Surveys and Questionnaires , Accidents, Occupational/prevention & control
8.
Int J Occup Saf Ergon ; 28(4): 2631-2644, 2022 Dec.
Article in English | MEDLINE | ID: mdl-34965852

ABSTRACT

Objectives. This research intends to investigate the responsibilities of the parties engaged in the implementation phase of the infrastructure projects in occupational health and safety, i.e., the consultant and contractor. Methods. A questionnaire was developed through the selection and modification of the responsibilities from the literature review. Results. The statistical analysis results show that the consultants and contractors both ranked the item 'The owner requires the contractor to implement the occupational safety standards within the bid' first in the owner responsibilities, having 0.67 relative importance index (RII). In the responsibilities of the consultant, the first ranked item was 'The consultant has a role in adopting occupational safety plans and contingency plans', having 0.66 RII. In the responsibilities of the contractor, the first ranked item was 'The contractor shall provide the insurance cover for all project crews', having 0.71 RII. In the responsibilities of the workers, the first ranked item was 'Workers know the handling of tools and equipment within the project', having 0.59 RII. Conclusion. Overall, there was general agreement between consultants and contractors to classify and arrange items because both face the same conditions and have the same working environment.


Subject(s)
Occupational Health , Humans , Workplace
9.
Materials (Basel) ; 14(23)2021 Nov 25.
Article in English | MEDLINE | ID: mdl-34885326

ABSTRACT

In reinforced concrete structures, the fiber-reinforced polymer (FRP) as reinforcing rebars have been widely used. The use of GFRP (glass fiber-reinforced polymer) bars to solve the steel reinforcement corrosion problem in various concrete structures is now well documented in many research studies. Hollow concrete-core columns (HCCs) are used to make a lightweight structure and reduce its cost. However, the use of FRP bars in HCCs has not yet gained an adequate level of confidence due to the lack of laboratory tests and standard design guidelines. Therefore, the present paper numerically and empirically explores the axial compressive behavior of GFRP-reinforced hollow concrete-core columns (HCCs). A total of 60 HCCs were simulated in the current version of Finite Element Analysis (FEA) ABAQUS. The reference finite element model (FEM) was built for a wide range of test variables of HCCs based on 17 specimens experimentally tested by the same group of researchers. All columns of 250 mm outer diameter, 0, 40, 45, 65, 90, 120 mm circular inner-hole diameter, and a height of 1000 mm were built and simulated. The effects of other parameters cover unconfined concrete strength from 21.2 to 44 MPa, the internal confinement (center to center spiral spacing = 50, 100, and 150 mm), and the amount of longitudinal GFRP bars (ρv = 1.78-4.02%). The complex column response was defined by the concrete damaged plastic model (CDPM) and the behavior of the GFRP reinforcement was modeled as a linear-elastic behavior up to failure. The proposed FEM showed an excellent agreement with the tested load-strain responses. Based on the database obtained from the ABAQUS and the laboratory test, different empirical formulas and artificial neural network (ANN) models were further proposed for predicting the softening and hardening behavior of GFRP-RC HCCs.

10.
Article in English | MEDLINE | ID: mdl-33805581

ABSTRACT

Infrastructure projects are the foundation for essential public services and have an influential position in societal development. Although the role of infrastructure projects is substantial, they can involve complexities and safety issues that lead to an unsafe environment, and which impacts the project key stakeholders. Therefore, this study aimed to evaluate the barriers to implementing occupational safety in infrastructure projects in the Gaza Strip, which cause serious threats and reduce project performance. To evaluate the barriers, 39 items were highlighted and modified as per the construction context and environment, and which later were distributed in the form of a questionnaire, to get feedback from consultants and contractors. The analysis shows that in the safety policy barriers group, consultants and contractors both ranked the item "a contractor committed to an occupational safety program is not rewarded" first. In the management barriers group, consultants and contractors both ranked the item "safety engineer does not have significant powers, such as stopping work when needed" in the first place. In the behavior and culture barriers group, consultants and contractors both ranked the item "workers who are not committed to occupational safety are not excluded" in the first place. Overall, both consultants and contractors shared the same viewpoint in classifying the barriers in the working environment. The outcome of this study is beneficial for Palestinian construction industry policymakers, so they can monitor the highlighted barriers in on-going infrastructure projects and can modify the safety guidelines accordingly.


Subject(s)
Construction Industry , Occupational Health , Humans , Middle East , Safety Management , Workplace
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