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Hidden in the mix: How a regionally specific aggregate affected St. Louis Missouri's built environment
Published in João Mascarenhas-Mateus, Ana Paula Pires, Manuel Marques Caiado, Ivo Veiga, History of Construction Cultures, 2021
This location along the Meramec also provided access for gravel and sand companies to collect materials and send them to St. Louis. The Meramec supplies two commodities: sand and gravel. Size differentiates one from each other. Gravel is conventionally defined as larger than 2 mm and is used as aggregate for concrete, roofing gravel, back fill, and for landscaping. Sand is defined as smaller than 2mm. Meramec sand and gravel are collected in two primary ways: by quarrying pits in flood plains adjacent to the river; and through dredging operations, where dredging machines collect and transport rock onto barges in the water way.
Making pavements using local materials and simple equipment
Published in Maxwell Lay, John Metcalf, Kieran Sharp, Paving Our Ways, 2020
Maxwell Lay, Metcalf John, Sharp Kieran
Gravel is a collective term for loose stones, typically smaller than 100 mm, and is at the other end of the spectrum to the sands and clays discussed above. If a low-cost pavement is being built in a region with available gravel, it might well be considered for use in subgrade and pavement construction. However, one common problem with gravels is that they are often found in river beds and glacial drifts where they been smoothed and rounded over many centuries. Such rounded stones are difficult to compact into a coherent and impermeable layer as they are easily pushed aside. This leads to the more common use of broken (or crushed) stones, as will described in following pages. However, a century later rounded stones found widespread use in cement concrete roads (Chapter 17).
Fundamentals of Soils
Published in John E. Schaufelberger, Giovanni C. Migliaccio, Construction Equipment Management, 2019
John E. Schaufelberger, Giovanni C. Migliaccio
Sand and gravel generally are easy to identify visually because of their size and shape. Gravel is an excellent construction material, particularly if fine particles are present to fill the void areas between the larger particles. Sand can be used for construction purposes, but needs to be confined to prevent lateral movement when loaded. Generally, organic soil also is easy to identify by its dark color, texture, and sometimes by its odor. Silt and clay are more difficult to identify. Two visual methods are described in Table 5.1. Silt and organic soils are very poor construction materials, because silts have very little strength and organic soils will decompose, creating voids in the soil matrix. Clay is an acceptable construction material, particularly when mixed with gravel.
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).
Liquefaction resistance behaviours of gravel steel slag
Published in European Journal of Environmental and Civil Engineering, 2022
Liyan Wang, Lianbang Wu, Yan Tang, Binghui Wang, Ke Sun, Aimable Ishimwe
Sand and gravel are main building materials and often used in artificial reclamation, subgrade cushions, earth-rock dams, and for other purposes. However, the continuous increment of scarcity level of sand and gravel in recent years needs urgently a new geo-backfill material with good liquefaction resistance. Steel slag is a recycled industrial solid waste. The aged eight-month steel slag usually could be used as backfill material (Deng et al., 2017, Wu et al., 2019; Liu & Zhang, 2016; Pao et al., 2016; Wu, 2011). At present, the research results of the dynamic characteristics of steel slag mixed with other materials include the following: the dynamic shear modulus and damping ratio of steel slag and sand mixtures was investigated (Li et al., 2018); the properties of mixtures of steel furnace slag, coal wash, and rubber crumbs used as sub-ballast were evaluated (Indraratna et al., 2018); and the effects of rubber crumbs on the cyclic behaviour of steel furnace slag and coal wash mixtures were researched (Qi et al., 2018).
The effect of polymer materials on the stabilization of forest road subgrade
Published in International Journal of Forest Engineering, 2021
Fatemeh Mousavi, Mohammad Avatefi Hemmat, Ehsan Abdi, Amirhossein Norouzi
The costs of gravel crushing and delivery have increased over recent years, reaching the average total amount of 18 USD per cubic meter at the time of this study. Assuming the application of two 20 cm layers of crushed gravel in road pavement (according to the Iranian national standard), the cost of stabilization per square meter of road surface is 7.2 USD, which is 15 and 16 times the cost of applying CBR Plus and RRPP, respectively Moreover, any amount of crushed aggregate applied to the road surface will sink into its natural clayey bed (if not stabilized) when wet. Also, exploiting forest mines or river beds have caused more environmental degradation in recent times, making alternative stabilization methods more attractive. This research showed that CBR Plus and RPP agents improved the engineering properties of the native fine-grained soil in District 2 (“Namkhaneh”) of the Kheirud Forest although its original quality was lower than coarse-grained materials from mines or riverbeds. Soil treatment with polymers may decrease transportation costs and have overall economic and environmental benefits by means of utilizing on-site materials. The results are based on laboratory experiments, so field investigations with polymer materials including CBR Plus and RPP are recommended for verification. In other words, field studies will help determine the mechanism of stabilization and evaluate the effect of these materials in actual conditions.