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Calculating determination on the critical heights of embankment in the degrading permafrost regions
Published in Jean-François Thimus, Ground Freezing 2000 - Frost Action in Soils, 2020
Dongqing Li, Ziwang Wu, Jianhong Fang, Yichi Li
The computer analysis are summarized in figure 2 to figure 4. Some of them, figure 2a, figure 3a and figure 4a show, respectively for the asphalt, concrete and gravel road surface, that the relations between the heights of embankment and the changes of the level of natural permafrost table under the middle sections of road in the twentieth year and in the thity year after construction on the same section in Hua Shixia Valley. On the other hand, figure 2b, figure 3b and figure 4b show the relations between the heights of embankment and the artificial permafrost table (changed permafrost table under the road surface) under the middle sections of the road. In figures, ● and ■ substitute respectively for the lines in twenty years and in thirty years after construction. The figures show, that, under the middle sections of the road, i.e. the changes of the permafrost table under the road and the critical design heights of embankment have a relationship with the age of the road after construction. In the same, Figures show that the influence of asphalt road surface following construction on the permafrost table is much greater than the influences of concrete and gravel road surfaces on that, and the heat-stable critical heights of embankment on the area of Chang Shitou Mountain along the road are 4.30, 1.40, 1.00 m and 4.50, 1.60, 1.00 m for a twenty year and thirty year analysis period after construction for asphalt, concrete and gravel road, respectively. The critical height of concrete road surfaces is equal to that of the gravel road surface in thirty years. The detailed results are summarized into the table 1.
Construction considerations
Published in Burt G. Look, Earthworks, 2023
Aggregate intended for a pavement structure is not appropriate for an unsurfaced gravel road. “Surface” gravel performs differently, and in this case, additional fines are required for increased binding. “Loose” gravel will “float” to the surface with time as the fines are lost due to trafficking and being blown away in dry and windy conditions. Therefore, unsurfaced roads require regular maintenance. An unpaved road that is not regularly maintained would benefit from the application of an effective dust palliative which provides flocculation or aggregation of the particles.
Gravel road classification based on loose gravel using transfer learning
Published in International Journal of Pavement Engineering, 2022
Nausheen Saeed, Roger G. Nyberg, Moudud Alam
Gravel roads connect areas of sparse populations and provide pathways for agricultural and forest goods. Gravel roads are also considered where the traffic volume is low, where gravel roads are more economical in comparison to paved roads. In Sweden, 21% of the public roads are gravel roads owned by the state, covering over 20 200 km. Besides, 74 000 km of gravel roads and forest roads of 210 000 km exist owned by the private sector (Kans et al.2020, Saeed et al.2020). The Swedish Road Administration (Trafikverket) rates the gravel road condition according to the severity of irregularities (corrugation and potholes), dust, and loose and gravel cross-section (Alzubaidi 2001). This assessment is done during the summertime when roads are free of snow (Hossein Alzubaidi 2014). Similar road distresses can be considered in other countries when assessing the quality of gravel roads. Gravel roads are made up of layers of soil and aggregates. In Figure 1, the structure of a gravel road is shown. The durability of gravel roads is low and requires regular maintenance. Some approaches are used to improve the safety of gravel roads using environment-friendly, cost-effective, and sustainable solutions. These solutions include a well-compacted road surface, a surface seal that creates a hard water resistance surface, and well-planned maintenance activities (Albatayneh et al.2019).
Validating the practicality of utilising an image classifier developed using TensorFlow framework in collecting corrugation data from gravel roads
Published in International Journal of Pavement Engineering, 2022
Osama Abu Daoud, Omar Albatayneh, Lars Forslof, Khaled Ksaibati
Gravel roads are comparatively inexpensive due to the simple construction procedures followed to construct these roads. However, gravel roads require more effort for maintenance and rehabilitation than paved roads. Recently, the technology revolution gave the researcher in all fields a chance to make a quantum leap in their fields, one feature of this technology revolution is developing machine learning models with capabilities to recognise and classify images (Zhang et al. 2019, Gu et al. 2018, Al-Suleiman (Obaidat) and Abu Daoud 2021). Based on its capabilities, Digital Image Processing has been adapted by many researchers in different fields as cutting edge tools for data collection, extraction and categorisation. In pavement management, new data collection methods have been introduced using the computer vision concept in the last decades. In the last few years, a lot of work has been deployed to develop automated pavement condition procedures by utilising deep learnings to build pavement detectors. As a result, several techniques were adapted to build the detectors such as: intensity-thresholding, edge detection, wavelet transforms, texture-analysis and machine learning (Zhang et al. 2019).
Developing performance models for treated gravel roads to evaluate the cost-effectiveness of using dust chemical treatments
Published in International Journal of Pavement Engineering, 2019
Mohammed Ali Okok, Promothes Saha, Khaled Ksaibati
The state of Wyoming owns a large inventory of gravel roads spread all around the state. Gravel roads are cheaper to build and maintain but one of their major detriments is dust generation. The Clean Air Act amendments passed by congress in 1990 required reduction of air pollution caused by transporting vehicles. The Congestion Mitigation and Air Quality Improvement (CMAQ) programme was initiated under this Act to support surface transportation projects and other related efforts that contribute to air quality improvements. For a number of years, Wyoming counties have benefited from CMAQ funds to apply dust suppressants to gravel roads and help reduce dust generation.