WITHDRAWN: Nanomaterials characteristics and current utilization status in rigid pavements: Mechanical features and Sustainability. A review

Galal

Beni-Suef Univ J Basic Appl Sci

et al. 2022

Background Rigid pavements have become an urgent demand in recent years, as these pavements need less maintenance and renovation than other types. However, traditional rigid pavement faces various challenges and difficulties over its lifetime. It has a much higher initial erection cost than asphalt pavements, a greater sensitivity to dynamic stresses, and a highly susceptible to temperature variations causing cracking. Previous works dealt with these drawbacks by using effective materials as alternatives to cement and/or aggregates in pavements mixtures. In the last few years, much interest has been carried out in nanomaterial applications to improve the mechanical performance of construction materials, which can also be used for rigid pavement constructions. This improvement is due to nanomaterials' role in concrete as nanoreinforcements and nanofillers. On the other hand, various types of fibers have been used to improve the performance of concrete constructions. This study investigates the effect of adding carbon nanotubes (CNTs) and steel fibers (SFs) to concrete mixtures. A series of experiments on concrete mixes with various weight percentages of CNTs (0%, 0.025%, 0.050%, and 0.075%) were added to the mixtures to determine the best cost and amount of CNTs to add to a concrete mix. Compressive, tensile, and flexure strength characteristics are investigated. In the second experimental stage of this work, the effect of adding steel fibers to the mixture was investigated. Results According to the results, the optimal carbon nanotube content in concrete is 0.05%. Compared to other concrete combinations with varying proportions of CNTs, this quantity offers the maximum compressive, tensile, and flexural strength. Additionally, SFs can improve the mechanical properties of the mix as well as enhance its post-cracking and fatigue behavior. Adding both CNTs with SFs increased compressive, tensile, and flexural strength by 22.7%, 29.3%, and 70.8%, respectively, more than the traditional pavement. Conclusion This work found that combining SFs with CNTs improves the mechanical properties of the concrete mortar, resulting in a stronger mortar that can withstand more loads than the traditional one.

Section: Introductionmentioning

confidence: 99%

Utilization of carbon nanotubes and steel fibers to improve the mechanical properties of concrete pavement

Galal

Beni-Suef Univ J Basic Appl Sci

et al. 2022

“…The advancement and progress of nanotechnology can upgrade the properties of building/construction materials, and thus assist sustainability [148][149][150][151]. There are obvious benefits related to the development of several nano-enabled products; however, there might also be dangers.…”

Section: Environmental and Health Concerns Of Nanomaterials Applications In Construction Industriesmentioning

confidence: 99%

Recent Advancements in the Nanomaterial Application in Concrete and Its Ecological Impact

2021

At present, nanotechnology is a significant research area in different countries, owing to its immense ability along with its economic impact. Nanotechnology is the scientific study, development, manufacturing, and processing of structures and materials on a nanoscale level. It has tremendous application in different industries such as construction. This study discusses the various progressive uses of nanomaterials in concrete, as well as their related health risks and environmental impacts. Nanomaterials such as nanosilica, nano-TiO2, carbon nanotubes (CNTs), ferric oxides, polycarboxylates, and nanocellulose have the capability to increase the durability of buildings by improving their mechanical and thermal properties. This could cause an indirect reduction in energy usage and total expenses in the concrete industry. However, due to the uncertainties and irregularities in size, shape, and chemical compositions, some nanosized materials might have harmful effects on the environment and human health. Acknowledgement of the possible beneficial impacts and inadvertent dangers of these nanosized materials to the environment will be extremely important when pursuing progress in the upcoming years. This research paper is expected to bring proper attention to the probable effects of construction waste, together with the importance of proper regulations, on the final disposal of the construction waste.

“…The utilization of rigid pavements becomes more needed nowadays as they are widely used for airfield runways, parking lots, industry roads and bridge dicks (Allujami, Jassam et al 2021). Rigid pavements are exposed to severe environmental factors and aggressive usage which could affect their functional conditions and may cause significant damages and distresses (Allujami, Jassam et al 2021, Ai, Jiang et al 2023. The deterioration of the pavement quality affects riding quality and can cause accidents which consider a risk for human health and safety (Steckenrider 2017).…”

Section: Introductionmentioning

confidence: 99%

Positioning and Detection of Rigid Pavement Cracks Using GNSS Data and Image Processing

Nasrallah,

Abdelfatah,

Attia

et al. 2023

Preprint

Modern pavement management systems depend mainly on pavement condition assessment to plan rehabilitation strategies. To assess pavement damages conventionally, manual inspection are performed by trained inspectors. This can be time-consuming and a source of risk for inspectors. Moreover, manual inspection can highly affected by the state of mind of inspectors. To overcome such problems, image based inspection using smartphone camera combined with image processing methods can be used. This combination is relatively cheaper and easier to use. This research proposes an automatic crack detection and mapping program for rigid pavement which can automate visual inspection process. The program consists of various image processing techniques that are used to identify and detect cracks from images. Detected cracks are defined in a pixel coordinate system. Cracks coordinates are converted from pixel coordinates to global coordinates in order to compute their lengths using Global Navigation Satellite Systems (GNSSs) data. The performance of the program was assessed with field study. Cracks quantification process is performed to determine crack lengths and areas. The results show that the precision, recall and accuracy values for the program’s image processing algorithm are 57.00%, 98.81% and 65.22% respectively.