Catálogo de publicaciones - revistas

<jats:p xml:lang="en">Coarse-grained soil (CGS), as a filler with the characteristics of high bearing capacity but difficult compaction for embankment construction, requires an appropriate thickness of a single compaction layer according to the influence depth of vertical dynamic stress. This paper used a numerical analysis using PFC2D following a scale model test with different particle gradations of compacted CGS fillers by adopting a modified PFWD. The results show that the influence depth is about 50 cm under the maximum impact stress of 0.066 MPa if defined the depth as the maximum stress attenuation to 20%. The compacted CGS filler with dense particle gradation and high strength has a rapid attenuation on vertical dynamic stress. Meanwhile, with the increase of stone content (P5, particle size ≥5 mm), the vertical dynamic stress of compacted CGS is attenuated exponentially. The maximum particle size also affects the attenuation of vertical dynamic stress, which needs further research. The findings support the development of non-destructive devices to inspect the compactness of subgrade construction rapidly.</jats:p>

<jats:p xml:lang="en">The innovations of the fourth industrial revolution (industry 4.0) encouraged the application of 3D printing technology to complement and subsequently replace the conventional construction method. This study assessed the awareness, application, drivers and barriers to the adoption of 3D printing technology for construction with a view to enhancing faster and sustainable construction process. Primary data were obtained with the use of structured questionnaires which were self-administered to medium and small-sized construction firms/contractors in Lagos State. Data collected were analyzed using descriptive and inferential statistics. The study established that the awareness and application levels of the technology are still very low. The findings showed that there exist statistically significant differences (0.039 ≤ p ≤ 0.017) in 6 drivers for the adoption of 3D printing technology, which is influenced by the client’s demand and desire. The study further established that inadequate power supply limits the adoption of 3D printing in the Nigerian construction industry. Implications are indicated by the findings on drivers and barriers of the technology which could help the construction industry in developing countries towards capability improvement for better adoption of 3D printing innovation and enhanced sustainable construction process.</jats:p>

<jats:p xml:lang="en">The innovative solutions offered by integrating 3D printing technology in construction over the conventional practices have established its globally rising adoption in the construction industry. This study assessed the awareness, application, drivers, and barriers to adopting enhanced 3D printing technology for construction to enhance faster and more sustainable construction processes. The study adopted a quantitative descriptive analysis which was based on primary data. The primary data were obtained using structured questionnaires self-administered to construction firms/contractors in Lagos State, Nigeria. Data collected were analyzed using descriptive and inferential statistics. The study established that the awareness and application levels of the technology are still deficient, as the vast majority (80.8%) of the firms who had an awareness of the technology in the study area acquired it through personal research and professional dialogue, rather than through the practical application of the technology. This finding showed that 3DP technology is a new construction option in the study area. The findings showed statistically significant differences among the drivers (0.039≤ p ≤0.017) for the adoption of 3D printing technology, which is influenced by the client’s demand and desire. The study further established that inadequate power source is a significant limiting factor to adopting 3D printing in the study area. Implications are indicated by the findings on the technology drivers and barriers that could help the construction industry in developing countries towards capability improvement for better adoption of 3D printing innovation and enhanced sustainable construction process.</jats:p>

<jats:p xml:lang="en">In recent years, significant advancements in developing large-scale 3D printers and construction materials have been made to meet industrial-scale 3D printing construction demand. Constructing the buildings and structural components using 3D concrete printing is significant. The main benefits of additive manufacturing (AM) are freedom of design, construction waste reduction, mass customization, and the ability to manufacture complex structures. The major issues include optimizing the printing material with suitable properties for 3D concrete printing. However, this technology for green building construction seems to improve conventional methods by reducing human resource requirements, high investment costs, and formworks. The research community's interest in 3D printing for architecture and construction has grown significantly over the last few years. As a result, there is a need to combine existing and ongoing research in this area to understand better current problems and their potential solutions based on future research work. This paper reviews the latest trend of research and state-of-the-art technologies in 3D printing in building and construction by analyzing the publications from 2002 to 2022. Based on the above-mentioned analysis of publications, printing methods, concrete printing systems, and the influence of constituent materials and chemical admixtures on concrete material properties are briefly discussed. The challenges and recommendations of 3DCP, including reinforcement, development of new materials, multi-nozzle combinations, life cycle assessment of 3DCP, and development of hybrid systems, are then examined. This paper concluded with a discussion of the limitations of existing systems and potential future initiatives to enhance their capability and print quality.</jats:p>

<jats:p xml:lang="en">In recent years, significant advancements in the development of large-scale 3D printers and construction materials have been made to meet the demand for industrial scale 3D printing construction. It is significant to construct the buildings and structural components by using 3D concrete printing. Additive manufacturing (AM) main benefits are freedom of design, construction waste reduction, mass customization, and ability to manufacture the complex structures. The major issues including the optimization of printing material which possess the suitable properties for 3D concrete printing. However, this technology towards the green building construction seems to improve the conventional methods by reducing the requirement of human resource, high investment cost, and formworks. The research community's interest in 3D printing for architecture and construction has grown significantly over the last few years. This paper review the latest trend of research and state of the art technologies in 3D printing in building and construction by analyzing the publications from 2002 to 2022. Based on aforementioned analysis of publications, printing methods, concrete printing systems and influence of constituent’s materials and chemical admixtures on concrete material properties are briefly discussed. Finally, this paper discussed the challenges and limitations of current systems, as well as potential future work to improve their capability and print quality.</jats:p>

<jats:p xml:lang="tr" />

<jats:p xml:lang="en">This article presents recent findings on the effect of thermal variances on pavements. It covers temperature measurement in asphalt pavement; the history of asphalt pavement temperature prediction models, determination of asphalt layer depth temperature; main factors contributing to temperature variations in the asphaltic pavement; energy balance in flexible pavements; asphalt pavement design incorporating the temperature factor; the effect of temperature on the structural performance of asphalt pavement; and environmental factors. The study concluded that temperature substantially affects the asphalt pavement layer's mechanical and physical material characteristics. This study has taken a close look at how pavement temperatures are measured and the models used to predict future temperatures. The research shows that temperature significantly affects the mechanical and physical properties of asphalt pavement layers.</jats:p>

<jats:p xml:lang="tr" />

<jats:p xml:lang="en">Fiber-reinforced polymer composites are well-studied and established products, and today they are being used in different industrial and non-industrial areas. However, the increased interest in recyclability and the concerns about climate change caused materials scientists to look for a non-petroleum-based alternative to synthetic fibers and polymers. Since the beginning of this century, natural fibers and biopolymers have attracted increasing interest each year for composite applications. Thanks to this interest, studies on natural fibers and biopolymers have increased significantly. Despite the high number of studies on natural fibers and natural fiber-reinforced polymers (NFRP), there are gaps in the literature. This work reviews studies on natural fibers, biopolymers, and biocomposites with their advantages, disadvantages, and limitations. Studies that focus on the ways to reduce or eliminate these disadvantages and limitations have also been looked at. Also, current challenges and future perspectives for natural fibers, biopolymers, and NFRPs have been discussed.</jats:p>

<jats:p xml:lang="en">The production of electrically conductive concrete was introduced years ago among construction materials, generally for anti-icing. The present study investigates the electrical, mechanical, dynamic, and microstructural properties of recycled ferrochrome filled cementitious mortars, containing single-walled carbon nanotubes (SWCNTs) and steel fiber. 7, 14, and 28-day non-destructive and 28-day compressive and bending tests of cementitious conductive mortars obtained from five different mixtures were performed. Two-point uniaxial method was used to determine the electrical conductivity properties of the samples. The damping ratio of the samples was obtained by performing dynamic resonance tests. Ultrasound pulse velocity (UPV) and Leeb hardness tests were performed as other non-destructive testing methods. Microstructure analysis at the interfaces of conductive concrete samples were characterized by scanning electron microscopy (SEM), EDS (Energy-Dispersive X-ray Spectroscopy), and X-ray diffraction (XRD). According to the experimental results, all data agreed and confirmed each other. When SWCNT is used in combination with steel fiber, the conductive mortar samples exhibited reasonable conductivity, while their mechanical properties turned out to below.</jats:p>