Railway ballast

Blastfurnace slag Iron smelting Nearly all used As roadstone, railway ballast, filter medium, aggregate for concrete, fertilizer and in manufacture of cement... 

These minerals are used for a variety of purposes—building, whitening, manufacture of lime, portland and natural cements, fertiliser, soft glass, refractory material (dolomite), as a flux in various metallurgical processes, source of CO2, railway ballast, macadam in lithography, cement concrete and asphalt concrete, in agriculture, as a solid diluent carrier in pesticides (dolomite). 

Utility telecommunication and railway right-of-ways may be contaminated by leaching of CDDs associated with chlorophenol-treated railway ties and utility poles. A study in British Columbia showed that CDDs and CDFs were not detected in parkland ditch sediments (control area), but were detected in farmland, utility, and railway right-of-way ditch sediments (Wan and van Oostdam 1995). Total mean CDD concentrations (mainly OCDD and HpCDD) ranged from 18.8 to 277 ng/kg (ppt) (dry weight) in ditch sediments and ballasts respectively. Concentrations of CDDs were much higher in ditch sediment... 

The efficacy of polyurethane and styrene butadiene rubber (SBR) as binders for ground rubber prepared from waste tires was compared to a formulation of a compound developed without binder. Without binder, the effect of both sulfur and accelerator content on tensile properties are studied, as well as the effect of ageing on these properties [29]. The suggested uses of the unbound product include rubber blocks, and ballast mats for railway applications. 

Train load according to European Standard EN 1991-2 Eurocode 1, Section 6, Rail traffic actions and other actions specifically for railway bridges and approaches. Section 6 of Eurocode EN1991-2 describes a 4-point load each 250 kN center-to-center 1.6 m. 0.8 m from each point load to total live load of 80 kN/m per track. Effective width is 3 m on 0.7 m depth (base ballast bed). This equals a maximum traffic load of 52kN/m. Due to spreading of the load in the... 

Lawrence, C. A., Tebay, R. N., Caddick, V. R. and Warwick, R.G. (2002), Geosynthetic Protection of Ballast and Sub-grade in Railway Foundation Structures , International Geosynthetics Society Annual Conference, Geosynthetics State of the Art and Recent Developments, NICE, 27-30 September 2002,901-904. 

Railways tracks are supported by granular material called ballast . The application of geosynthetics in railways is therefore somewhat similar to unpaved roads and can be considered basically in two categories ... 

The essence of railway dynamics is the transfer of forces at the wheel rail interface. The energy from the motion of the train is taken up as elastic deformation in the track structure consisting of the rail, sleepers, dry crust, ballast and soil. The elastic response in the ground depends both in magnitude and characteristics on a number of parameters, e.g. train mass, suspension parameters, train geometry, rail irregularities and soil material characteristics (Ching, 2004). 

The former Northwestern Institute of the China Railway Academy of Sciences (Lanzhou) established a research station at Fenghuo Shan in 1963 at about 4,800 m (15,748 ft) on the north side of the Tanggula Mountains. This research station is still in use, and a series of experiments were carried out to evaluate various methods of stabilizing slopes on a short, improvised rail bed that lacked the ballast and rails of the real thing. Over 20 years of data were obtained before the railway was designed. 

Rail and track (39%). The causes under this category are caused by or along the railway line, including the ballast, sleepers, switches, and objects placed on or close to the track. The category also includes work on the track (e.g., maintenance and shunter actions). 

Petroleum products are transported by tankers, pipelines, railway tank cars, and tank trucks. The outside submerged surfaces of tankers and the outside surfaces of underground and underwater pipelines are protected by coatings and by using cathodic protection. Cathodic protection is also applied to the inside of tankers to prevent corrosion by seawater used for washing or ballast. 

Indiaratna, B., Nimbalkar, S.S., 2013. The role of geosynthetics in improving the behaviour of ballasted rail track. In Venkatappa Rio, G. (Ed.), Geosynthetics in Railway Track. Central Board of Irrigation and Power, India, pp. 59—85. 

Limestone is a sedimentary rock composed largely of ealeium earbonate. Various forms of limestone are contaminated with magnesium earbonate (dolomitic limestone), clay (argillaceous limestone), and sand or quartz (silaceous limestone). Marble is the crystallized form of limestone. Limestone has many uses, particularly in the construction industry where it is used as a building material, as hardcore and ballast in road and railway eonstruction, and mixed with clay for the manufacture of cement. Limestone is extracted by quarrying, and the main health hazard is related to the silica content of the limestone. Exposure to airborne limestone dust itself appears to carry little risk (1). 

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