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Strength and permeability of fiber-reinforced concrete incorporating waste materials

  • Xu, Yun;Xu, Yin;Almuaythir, Sultan;Marzouki, Riadh
    • Advances in concrete construction
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    • v.13 no.2
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    • pp.133-152
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    • 2022
  • Ecological issues such as natural resource reduction and enormous waste disposals are increasingly leading in developing civilization toward sustainable construction. The two primary environmental issues are the depletion of natural resources and the disposal of trash in open landfills. Waste steel fiber (WSF) was investigated for usage as a cement-based concrete (CBC) constituent in this research. Recycling waste fibers both makes cement composites more long and cost-effective, also aids in pollution reduction. The objective of this study is to analyze the impacts of waste fiber on the fresh and mechanical features of concrete using recycled additives. A comparative research on the durability and mechanical qualities of fiber-reinforced concrete (FRC) constructed with natural aggregates was conducted for this aim. The obstacles to successful WSF recycling methods application in the building industry have been investigated, resulting that CBCs with these fibers make an economic and long lasting choice to deal with waste materials. The workability of fiber enhanced concrete was found to be comparable to that of normal concrete. Fibers have a considerable impact on the splitting tensile strength, flexural and compressive strength of recycled concrete. Fiber may enhance the water permeability. When the WSF content is 0.6 kg/m3, the water absorption is nearly half. Fibers would have no effect on its permeability.

Behavior of GGBS concrete with pond ash as a partial replacement for sand

  • Maheswaran, J.;Chellapandian, M.;Kumar, V.
    • Advances in concrete construction
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    • v.13 no.3
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    • pp.233-242
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    • 2022
  • An attempt is made to develop an eco-friendly concrete with ground granulated blast furnace slag (GGBS) and pond ash as partial replacement materials for cement and fine aggregate, respectively without compromising the strength and durability. Sixteen concrete mixes were developed by replacing cement and fine aggregate by GGBS and pond ash, respectively in stages of 10%. The maximum replacement levels of cement and fine aggregates were 50% and 30% respectively. Experimental results revealed that the optimum percentage of GGBS and pond ash replacement levels were 30% and 20% respectively. The optimized mix was used further to study the flexural behavior and durability properties. Reinforced Concrete (RC) beams were cast and tested under a four-point bending configuration. Also, the specimens prepared from the optimized mix were subjected to alternate wet and dry cycles of acid (3.5% HCl and H2SO4) and sulphate (10% MgSO4) solutions. Results show that the optimized concrete mix with GGBS and pond ash had a negligible weight loss and strength reduction.

Mechanical behavior test and analysis of HEH sandwich external wall panel

  • Wu, Xiangguo;Zhang, Xuesen;Tao, Xiaokun;Yang, Ming;Yu, Qun;Qiu, Faqiang
    • Advances in concrete construction
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    • v.13 no.2
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    • pp.153-162
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    • 2022
  • Prefabricated exterior wall panel is the main non-load-bearing component of assembly building, which affects the comprehensive performance of thermal insulation and durability of the building. It is of great significance to develop new prefabricated exterior wall panel with durable and lightweight characteristics for the development of energy-saving and assembly building. In the prefabricated sandwich insulation hanging wall panel, the selection of material for the outer layer and the arrangement of the connector of the inner and outer wall layers affect the mechanical performance and durability of the wall panels. In this paper, high performance cement-based composites (HPFRC) are used in the outer layer of the new type wall panel. FRP bars are used as the interface connector. Through experiments and analysis, the influence of the arrangement of connectors on the mechanical behaviors of thin-walled composite wall panel and the panel with window openings under two working conditions are investigated. The failure modes and the role of connectors of thin-walled composite wallboard are analyzed. The influence of the thickness of the wall layer and their combination on the strain growth of the control section, the initial crack resistance, the ultimate bearing capacity and the deformation of the wall panels are analyzed. The research work provides a technical reference for the engineering design of the light-weight thin-walled and durable composite sandwich wall panel.

Parametric study of shear capacity of beams having GFRP reinforcement

  • Vora, Tarak P.;Shah, Bharat J.
    • Advances in concrete construction
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    • v.13 no.2
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    • pp.183-190
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    • 2022
  • A wide range of experimental bases and improved performance with different forms of Fiber Reinforced Polymer (FRP) have attracted researchers to produce eco-friendly and sustainable structures. The reinforced concrete (RC) beam's shear capacity has remained a complex phenomenon because of various parameters affecting. Design recommendations for the shear capacity of RC elements having FRP reinforcement need a more experimental database to improve design recommendations because almost all the recommendations replace different parameters with FRP's. Steel and FRP are fundamentally different materials. One is ductile and isotropic, whereas the other is brittle and orthotropic. This paper presents experimental results of the investigation on the beams with glass fiber reinforced polymer (GFRP) reinforcement as longitudinal bars and stirrups. Total twelve beams with GFRP reinforcement were prepared and tested. The cross-section of the beams was rectangular of size 230 × 300 mm, and the total length was 2000 mm with a span of 1800 mm. The beams are designed for simply-supported conditions with the two-point load as per specified load positions for different beams. Flexural reinforcement provided is for the balanced conditions as the beams were supposed to test for shear. Two main variables, such as shear span and spacing of stirrups, were incorporated. The beams were designed as per American Concrete Institute (ACI) ACI 440.1R-15. Relation of VExp./VPred. is derived with axial stiffness, span to depth ratio, and stirrups spacing, from which it is observed that current design provisions provide overestimation, particularly at lower stirrups spacing.

Reliability study of CFRP externally bonded concrete beams designed by FIB bulletin 14 considering corrosion effects

  • Dehghani, Hamzeh
    • Advances in concrete construction
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    • v.13 no.2
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    • pp.191-198
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    • 2022
  • FIB is introduced as the sole guideline for the design purpose that results in a practical relationship for the torsional capacity of concrete beams strengthened with carbon fiber-reinforced polymer (CFRP). This study applies first-order reliability method to assess the reliability evaluation of the torsional capacity of CFRP-strengthened beams on the basis of FIB guidelines. In terms of steel reinforcement losses, this study applies a corrosion model to investigate the ceaseless deterioration of the existing structure. Hence, the average of reliability indices varies between 2.68 and 2.80, indicating the reliability viewpoint of the design methodologies. The average values are somehow low compared to the target values of reliability (3.0 or 3.5) applied in the calibration stage of the FIB guideline. In this way, the partial safety factors may change in the forthcoming guideline revisions. For this aim, the reliability of strengthening ratio was applied to assess the variation in the average value of the reliability index with different partial safety factors. The performance of parametric study for the factor proved that minimum values of 1.60 and 2.32 are required for target values of reliability (3.0 and 3.5), respectively.

Lubrication phenomenon in the stagnation point flow of Walters-B nanofluid

  • Muhammad Taj;Manzoor Ahmad;Mohamed A. Khadimallah;Saima Akram;Muzamal Hussain;Madeeha Tahir;Faisal Mehmood Butt;Abdelouahed Tounsi
    • Advances in concrete construction
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    • v.15 no.5
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    • pp.303-312
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    • 2023
  • The present study investigates the effects of Cattaneo-Christov thermal effects of stagnation point in Walters-B nanofluid flow through lubrication of power-law fluid by taking the slip at the interfacial condition. For the solution, the governing partial differential equation is transformed into a series of non-linear ordinary differential equations. With the help of hybrid homotopy analysis method; that consists of both the homotopy analysis and shooting method these equations can be solved. The influence of different involved constraints on quantities of interest are sketched and discussed. The viscoelastic parameter, slip parameters on velocity component and temperature are analyzed. The velocity varies by increase in viscoelastic parameter in the presence of slip parameter. The slip on the surface has major effect and mask the effect of stagnation point for whole slip condition and throughout the surface velocity remained same. Matched the present solution with previously published data and observed good agreement. It can be seen that the slip effects dominates the effects of free stream and for the large values of viscoelastic parameter the temperature as well as the concentration profile both decreases.

Integrating a Machine Learning-based Space Classification Model with an Automated Interior Finishing System in BIM Models

  • Ha, Daemok;Yu, Youngsu;Choi, Jiwon;Kim, Sihyun;Koo, Bonsang
    • Korean Journal of Construction Engineering and Management
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    • v.24 no.4
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    • pp.60-73
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    • 2023
  • The need for adopting automation technologies to improve inefficiencies in interior finishing modeling work is increasing during the Building Information Modeling (BIM) design stage. As a result, the use of visual programming languages (VPL) for practical applications is growing. However, undefined or incorrect space designations in BIM models can hinder the development of automated finishing modeling processes, resulting in erroneous corrections and rework. To address this challenge, this study first developed a rule-based automated interior finishing detailing module for floors, walls, and ceilings. In addition, an automated space integrity checking module with 86.69% ACC using the Multi-Layer Perceptron (MLP) model was developed. These modules were integrated into a design automation module for interior finishing, which was then verified for practical utility. The results showed that the automation module reduced the time required for modeling and integrity checking by 97.6% compared to manual work, confirming its utility in assisting BIM model development for interior finishing works.

Physicochemical properties and autogenous healing performance of ternary blended binders composed of OPC-BFS-CSA clinker

  • H.N. Yoon;Joonho Seo;Naru Kim;H.M. Son;H.K. Lee
    • Advances in concrete construction
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    • v.15 no.1
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    • pp.11-22
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    • 2023
  • Autogenous healing of concrete can be helpful in structural maintenance by healing cracks using a healing material created by the precipitation of calcite and by the hydration of unhydrated binder around the cracks. Against this backdrop, this study investigated the physicochemical properties and autogenous healing performance of ternary blended binder composed of ordinary Portland cement (OPC), blast furnace slag (BFS), and calcium sulfoaluminate (CSA) clinker. Ternary blended binders with various contents of OPC-BFS-CSA clinker were prepared, and their physicochemical properties and autogenous healing performances were examined using various analytical techniques and visually observed using a microscope. The obtained results indicated that increase in the BFS content accompanied the increased the amount of unreacted BFS even after 28 days of curing and had a positive effect on the autogenous healing performance due to its latent hydration. However, replacing the CSA clinker did not increase the autogenous healing performance owing to an insufficient sulfate source for the formation of ettringite. The main precipitates around the cracks were calcite, C-S-H. Other hydration products such as portlandite, monosulfate, and ettringite, which were not found in the Raman and scanning electron microscope analyses.

Anti-corrosion impact of green synthesis of Silica nanoparticles for the sports structures in physical exercise activities

  • Zhixin Zhang;Zhiqiang Cai;Khidhair Jasim Mohammed;H. Elhosiny Ali
    • Advances in concrete construction
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    • v.15 no.1
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    • pp.41-46
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    • 2023
  • Sport has no age limit and can be done anywhere and in any condition with minimal equipment. The existence of sports spaces in all parts of the world is considered a citizen's right. One of the activities carried out in this field is installing sports equipment and structures in parks and encouraging citizens to use this equipment for physical health with the least cost and facilities. Installing sports structures in open spaces such as parks is a practical step for developing citizens' sports. Although using devices in parks is acceptable, it is more critical to meet scientific and technical standards. The components of these structures must have high strength and endurance against changes in environmental conditions such as humidity, temperature difference, and corrosion. Among the various causes of material degradation, corrosion has always been one of several fundamental causes of metal equipment failure. Sports structures in open spaces are not safe from corrosion. Uniform corrosion is the most common type of corrosion. This corrosion usually occurs uniformly through a chemical or electrochemical reaction across the surface exposed to the corrosive environment. Rust and corrosion of outdoor sports structures are examples of this corrosion. For this reason, in this research, with the green synthesis of silica nanoparticles and its application in outdoor sports structures, the life span of these structures can be increased for the use of physical exercises as well as their quality.

A review on the effect of marble waste on properties of green concrete

  • Rachid Djebien;Amel Bouabaz;Yassine Abbas;Yasser N. Ziada
    • Advances in concrete construction
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    • v.15 no.1
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    • pp.63-74
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    • 2023
  • All production and consumption activities produce wastes, which often cause damage to our environment and multiple risks to the human health. The valorization of these wastes in concrete technology is a future solution that will allow finding other construction materials sources, optimizing energy consumption and protecting the environment. Among these wastes, there is the marble waste. Every year, huge amount of marble waste is discarded as dust or aggregates form, in open-air storage areas causing serious problems for the environment and public health. In this context, the incorporation of marble waste as a replacement of ordinary aggregates or cement in concrete composition is actively investigated by researchers. This paper presents a comprehensive review of published studies over the last 20 years, dealing the effect of marble waste on fresh and hardened properties of concrete. Most of the studies carried out have used marble waste as dust with substitution rates between 5 and 20%. Besides the economic and ecological benefits, this review showed that marble waste can improve the physical, mechanical and durability properties of concrete. This improvement depends on the form (dust, fine aggregate or coarse aggregate), substitution method (as cement or aggregates replacement) and substitution rate of marble waste. Additionally, the review results showed that the use of 10-15% of marble waste dust as cement substitution can lead to increase the compressive strength.