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Relationships Between Abrasion Index and Shape Properties of Progressively Abraded Dolerite Railway Ballasts


Sub-angular-shaped aggregates are used as rail foundation ballasts and must remain sub-angular during their service life time to maintain particle–particle interlocking, in order to ensure the stability of the rail line and prevent accidents by derailment. Here, the screening of dolerite quarry aggregates for use as railway foundation ballasts was investigated by employing simple digital image and chart methods. The average particle size (d 50), flakiness index (FI), Los Angeles abrasion index (LAAI), sphericity (SPH) and roundness (RND) were determined for two batches of dolerite ballasts from the Rooikraal quarry in Johannesburg and Ngagane quarry in Newcastle. Thirty samples from each of the two batches of ballast were analysed. The ballasts were progressively abraded using a Los Angeles abrasion device and were analysed after each cycle of abrasion. A decrease in d 50 and an increase in FI with increased number of abrasion cycles were observed for both batches of dolerite ballast. The difference in the chart and digital image values of RND and SPH were marginal before abrasion; however, these differences increased with each abrasion cycle. The LAAI, d 50, mean RND and mean SPH correlated significantly and were found to have high regression coefficients. Thus, statistical models are proposed for the non-destructive routine screening of in-place ballasts in order to track marginal changes in aggregate shapes, facilitate ballast replacement programmes and avoid rail line instability.

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  • American Society for Testing and Materials (ASTM) (1995) Los Angeles abrasions test C. ASTM Publication, Philadelphia, pp 131–189

  • Australian Rail Track Corporation (ARTC) (2007) Infrastructure Standards: ARTC Extranet. Home page at: Retrieved 20 April 2011

  • Brink ABA (1984) Engineering geology of southern Africa, vol 4. Building Publications, Silverton, Pretoria

  • Das BM, Ramana GV (2011) Principles of soil dynamics, 2nd edn. Cengage Learning, Stanford

    Google Scholar 

  • Dobkins JE, Folk RL (1970) Shape development on Tahiti-nui. J Sedim Res 40:1167–1203

    Google Scholar 

  • Fernlund JMR (2005) 3-D image analysis size and shape method applied to the evaluation of the Los Angeles test. Eng Geol 77:57–67

    Article  Google Scholar 

  • Handy RL, Spangler MG (2007) Soil and foundation principles and practice, 5th edn. McGraw-Hill, New York

    Google Scholar 

  • Hayakawa Y, Oguchi T (2005) Evaluation of gravel sphericity and roundness based on surface-area measurement with a laser scanner. Comput Geosci 31:735–741

    Article  Google Scholar 

  • Indraratna B, Khabbaz H, Salim W, Christie D (2006) Geotechnical properties of ballast and the role of geosynthetics in rail track stabilisation. Ground Improv 10:91–101

    Article  Google Scholar 

  • Kleyn E, Bergh A, Botha P (2009) Practical implications of the relation between the clay mineral content and the Plasticity Index of dolerite road construction material. J South Afr Inst Civil Eng 51:2–5

    Google Scholar 

  • Krumbein WC (1941) The effects of abrasion on the size, shape and roundness of rock fragments. J Geol 49:482–520

    Article  Google Scholar 

  • Kuenen PH (1956) Experimental abrasion of pebbles: 2. Rolling by current. J Geol 64:336–368

    Article  Google Scholar 

  • Kwan AKH, Mora CF, Chan HC (1999) Particle shape analysis of coarse aggregate using digital image processing. Cem Concr Res 29:1403–1410

    Article  Google Scholar 

  • Lanaro F, Tolppanen P (2002) 3D characterization of coarse aggregates. Eng Geol 65:17–30

    Article  Google Scholar 

  • Lurie J (2004) South African geology for mining, metallurgical hydrological and civil engineering. Lupon Publishing, Johannesburg

    Google Scholar 

  • Masad EA, Al-Rousan T, Button JW, Little DN, Tutumluer E (2007) Test methods for characterizing aggregate shape, texture, and angularity. National Cooperative Highway Research Program (NCHRP) report 555

  • Okonta FN, Magagula SG (2011) Railway foundation properties of some South African quarry stones. Electr J Geot Eng 16A:180–197

    Google Scholar 

  • Powers MC (1953) A new roundness scale for sedimentary particles. J Sedim Res 23:117–119

    Article  Google Scholar 

  • Raymond GP (1985) Railroad ballast specification and evaluation. In: Handbook of transportation engineering, 3rd edn. McGraw-Hill, London

    Google Scholar 

  • Rittenhouse G (1943) A visual method of estimating two-dimensional sphericity. J Sedim Res 13:79–81

    Google Scholar 

  • Sherif MA, Ishibashi I, Gaddah AH (1972) Damping ratio for dry sands. J Geotech Eng Div ASCE 103(GT7):743–756

    Google Scholar 

  • Sloane DJ (1991) Some physical properties of dolerite. Report of the Division of Mines and Mineral Resources—report no. 1991/22, Pretoria

  • South African National Standards (SANS) (2008) Test for rock materials. SANS P: 12A, Pretoria

  • Spoornet (1998) Specification for the supply of stone. Test Bulletin of South African Freight Rail Johannesburg: S406, Pretoria

  • Swan B (1974) Measures of particle roundness; a note. J Sedim Res 44:572–577

    Google Scholar 

  • Wadell H (1933) Sphericity and roundness of rock particles. J Geol 41:310–331

    Article  Google Scholar 

Download references


The first draft of this document was edited with an online editor. The subsequent drafts of this document were edited by my colleague, Mr. Walter Wallace, the senior academic administrator at the Department of Civil Engineering Science, University of Johannesburg. The author is very grateful.

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Correspondence to F. N. Okonta.

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Okonta, F.N. Relationships Between Abrasion Index and Shape Properties of Progressively Abraded Dolerite Railway Ballasts. Rock Mech Rock Eng 47, 1335–1344 (2014).

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  • Railway ballasts
  • Sphericity
  • Roundness
  • Los Angeles abrasion Index
  • Flakiness index