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Industrial Minerals
Published in Earle A. Ripley, E. Robert Redmann, Adèle A. Crowder, Tara C. Ariano, Catherine A. Corrigan, Robert J. Farmer, L. Moira Jackson, Environmental Effects of Mining, 2018
A. Ripley Earle, Robert E. Redmann, Adèle A. Crowder, Tara C. Ariano, Catherine A. Corrigan, Robert J. Farmer, Earle A. Ripley, E. Robert Redmann, Adèle A. Crowder, Tara C. Ariano, Catherine A. Corrigan, Robert J. Farmer, L. Moira Jackson
Most sand and gravel is used for road construction and concrete aggregate. Crushed stone is used for the same purposes; it is also used for construction of railway beds, earth dams, and breakwaters. According to Vagt (1994c), demand has increased steadily since World War II. Environmental impacts have been growing concomitantly, and all jurisdictions, particularly provincial and municipal, are paying more attention to aggregate operations, particularly with regard to reclamation.
Aggregates
Published in M. Rashad Islam, Civil Engineering Materials, 2020
US domestic production and use of construction aggregates amount to 2.5 billion tons of crushed stone, sand, and gravel, valued at $25.1 billion per year, and the aggregates industry employs approximately 100,000 highly skilled employees (NSSGA 2019). Another survey by the USGS (2013) shows approximately 1.3 billion tons of crushed stone, worth about $12 billion, was produced by 1,550 companies operating 4,000 quarries, 91 underground mines, and 210 sales/distribution yards in the United States in 2012. Of the total crushed stone produced in 2012, about 69% was limestone and dolomite, 14% was granite, 7% was traprock, 5% was miscellaneous stone, and 4% was sandstone and quartzite. Of the portion of total crushed stone produced in 2012, 82% was used as a construction material, mostly for road construction and maintenance, and 10% was used for cement manufacturing. Approximately 927 million tons of construction sand and gravel worth $6.4 billion was produced in 2012. About 43% of construction sand and gravel was used as concrete aggregates; 26% for road base, coverings, and stabilization; 12% as construction fill; and 12% as asphalt concrete aggregates and used in other asphalt-aggregate products. Another survey shows about 27% of total crushed stone is used in PCC production and 9% is used in AC production, while about 16% is used in road bases as unbound layers, and the remaining 48% is used in other applications. About 17% of total gravel and sand is used in PCC production and 16% is used in AC production, while about 26% is used in road bases as unbound layers, and the remaining 41% is used in other applications (Somayaji 2001).
A comparative study on the performance of RCC for pavements casted in laboratory and field
Published in International Journal of Pavement Engineering, 2022
Yavuz Abut, Salih Taner Yildirim, Onur Ozturk, Nilufer Ozyurt
As indicated before, 2.2 km RCC pavement was constructed in the scope of the study. To construct the road economically, all the materials used in the study were selected from the local materials by considering their availability. CEM I 42.5 R type Portland cement was used as a cementitious material. Besides, 2 types of crushed stone (No 1 (4.75–19 mm with 2.72 g/cm3 density) and No 2 (9.5–25 mm with 2.70 g/cm3 density)) and 2 types of crushed sand (S1 (0–4.75 mm with 2.63 g/cm3 density) and S2 (0–4.75 mm with 2.65 g/cm3 density)) were used as aggregates. Properties of the cement and aggregates used in this study were presented extensively in a previous study (Abut and Yildirim 2017). Additionally, mixture design, sample preparation, curing and mechanical testing procedures followed in preliminary design was also presented in the previous studies (Abut and Yildirim 2017, Abut and Yildirim 2019). However, followed procedure was again summarised below to provide integrity.
State of the art review on design and performance of microsurfacing
Published in Road Materials and Pavement Design, 2020
Nishant Bhargava, Anjan Kumar Siddagangaiah, Teiborlang L. Ryntathiang
Aggregates are the mineral materials accounting for major volume of the microsurfacing mix (Gransberg, 2010). Crushed stone like granite, limestone, sandstone or high-quality aggregates are used (Broughton & Lee, 2012; ISSA A143, 2010) with crushing operations to be conducted on single source for microsurfacing application (Broughton & Lee, 2012). The quality tests for aggregates along with aggregate gradation adopted by various agencies are shown in Tables 2 and 3, respectively.
Inverted base pavements: construction and performance
Published in International Journal of Pavement Engineering, 2019
Efthymios Papadopoulos, Juan Carlos Santamarina
Earlier pavements in South Africa were built with granular bases made of natural or stabilised gravel and various forms of Macadam (Jooste and Sampson 2005). As their use extended to high-volume roads, crushed stone became the standard base material for high-traffic roads.