Skip to main content
SpringerLink
Log in

Utilizing the strength conversion factor in the estimation of uniaxial compressive strength from the point load index

  • Original Paper
  • Published:
Bulletin of Engineering Geology and the Environment Aims and scope Submit manuscript

Abstract

The strength conversion factor (k) is the ratio between the uniaxial compressive strength (UCS) and the point load index (PLI). It has been used to estimate the UCS from the PLI since the 1960s. Many researchers have investigated the relationship between UCS and PLI for various rock types of different geological origins, such as igneous, sedimentary, and metamorphic rocks. In this study, the k values for subclasses of igneous (pyroclastic, volcanic, and plutonic), sedimentary (chemical and clastic), and metamorphic (foliated and nonfoliated) rocks were evaluated. For this purpose, UCS and PLI data for a total of 410 rock samples extracted from literature published around the world as well as UCS and PLI data obtained in this work for 80 rock samples taken from the Eastern Black Sea Region in Turkey were evaluated together to determine the k values of different rock classes. Strength conversion factors were obtained using zero-intercept regression analysis, formulation, and a graphical approach. This study confirmed that there is no single k value that is applicable to all rock classes. According to statistical analyses, k varied between 12.98 and 18.55 for the rocks studied. These findings demonstrate that the k values derived in this work can be reliably used to estimate the strengths of rock samples with specific lithologies.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13

Similar content being viewed by others

References

  • Adebayo B, Opafunso ZO, Akande JM (2010) Drillability and strength characteristics of selected rocks in Nigeria. AU JT 14(1):56–60

    Google Scholar 

  • Alemdag S, Kaya A, Gurocak Z, Dag S (2011) Excavatability properties of rock masses having different weathering degrees: an example of Gumushane granitoid, Gumushane, NE Turkey (in Turkish). J Eng Geol 35(2):135–152

  • Azimian A, Ajalloeian R, Fatehi L (2014) An empirical correlation of uniaxial compressive strength with p-wave velocity and point load strength index on marly rocks using statistical method. Geotech Geol Eng 32:205–214

    Article  Google Scholar 

  • Basu A, Kamran M (2010) Point load test on schistose rocks and its applicability in predicting uniaxial compressive strength. Int J Rock Mech Min Sci 47:823–828

    Article  Google Scholar 

  • Bieniawski ZT (1975) Point load test in geotechnical practice. Eng Geol 9(1):1–11

    Article  Google Scholar 

  • Broch E, Franklin JA (1972) The point-load strength test. Int J Rock Mech Min Sci Geomech Abstr 9(6):669–676

    Article  Google Scholar 

  • Brook N (1985) The equivalent core diameter method of size and shape correction ın point load testing. Int J Rock Mech Min Sci Geomech Abstr 22:61–70

    Article  Google Scholar 

  • Cargill JS, Shakoor A (1990) Evaluation of empirical methods for measuring the uniaxial strength of rock. Int J Rock Mech Min Sci 27:495–503

    Article  Google Scholar 

  • Catallini LE (1986) Rock mass classification for preliminary tunnel design: Sterrita site. MSc thesis. University of Arizona, Tucson

  • Chau KT, Wong RHC (1996) Uniaxial compressive strength and point load strength of rocks. Int J Rock Mech Min Sci Geomech Abstr 33(2):183–188

    Article  Google Scholar 

  • Cobanoglu I, Celik SB (2008) Estimation of uniaxial compressive strength from point load strength, Schmidt hardness and P-wave velocity. Bull Eng Geol Environ 67:491–498

    Article  Google Scholar 

  • D’Andrea DV, Fisher RL, Fogelson DE (1964) Prediction of compression strength from other rock properties. Colo School Mines Q 59(4b):623–640

    Google Scholar 

  • Deere DU, Miller RP (1966) Engineering classifications and index properties of intact rock. Tech Rep AFWL-TR 65-116. Air Force Weapons Laboratory, Kirtland Air Force Base, Albuquerque, p 300

  • Diamantis K, Gartzos E, Migros G (2009) Study on uniaxial compressive strength, point load strength index, dynamic and physical properties of serpentinites from Central Greece: test results and empirical relations. Eng Geol 108:199–207

  • Fener M, Kahraman S, Bilgil A, Gunaydin O (2005) A comparative evaluation of indirect methods to estimate the compressive strength of rocks. Rock Mech Rock Eng 38(4):329–343

    Article  Google Scholar 

  • Forster IR (1983) The influence of core sample geometry on the axial point load test. Int J Rock Mech Min Sci 20:291–295

    Article  Google Scholar 

  • Ghosh DK, Srivastava M (1991) Point load strength: an index for classification of rock material. Bull Int Assoc Eng Geol 44:27–33

    Article  Google Scholar 

  • Grasso P, Xu S, Mahtab A (1992) Problems and promises of index testing of rocks. In: Proc 33rd US Symp Rock Mechanics, Sante Fe, NM, USA, 3–5 June 1992, pp 879–888

  • Greminger M (1982) Experimental studies of the influence of rock anisotropy on size and shape effects in point-load testing. Int J Rock Mech Min Sci 19:24–246

    Article  Google Scholar 

  • Grene BH (2001) Predicting the unconfined compressive strength of mudrocks for design of structural foundations. PhD thesis. Kent State University, Kent

  • Gul Y, Ceylanoglu A (2013) Evaluation of plate loading tests on some rock formations for assessing the ground bearing capacity. Bull Eng Geol Environ 72:131–136

    Article  Google Scholar 

  • Gunsallus KL, Kulhawy FH (1984) A comparative evaluation of rock strength measures. Int J Rock Mech Min Sci 21:233–248

    Article  Google Scholar 

  • Gurocak Z, Alemdag S, Zaman MM (2008) Rock slope stability and excavatability assessment of rocks at the Kapikaya Dam site, Turkey. Eng Geol 96:17–27

  • Hassani FP, Scoble MJJ, Whittaker BN (1980) Application of point-load index test to strength determination of rock and proposals for new size-correction chart. In: Summers DA (ed) Proc 21st US Symp Rock Mechanics, Rolla, MO, USA, 28–30 May 1980, pp 543–553

  • Hawkins AB (1998) Aspect of rock strength. Bull Eng Geol Environ 57:17–30

    Article  Google Scholar 

  • ISRM (1985) Suggested method for determining point load strength. Int J Rock Mech Min Sci Geomech Abstr 22(2):53–60

    Google Scholar 

  • Kahraman S (2001) Evaluation of simple methods for assessing the uniaxial compressive strength of rock. Int J Rock Mech Min Sci 38:991–994

    Google Scholar 

  • Kahraman S (2014) The determination of uniaxial compressive strength from point load strength for pyroclastic rocks. Eng Geol 170:33–42

    Article  Google Scholar 

  • Kahraman S, Gunaydin Fener M (2005) The effect of porosity on the relation between uniaxial compressive strength and point load index. Int J Rock Mech Min Sci 42:584–589

    Article  Google Scholar 

  • Kahraman S, Gunaydin O (2009) The effect of rock classes on the relation between uniaxial compressive strength and point load index. Bull Eng Geol Environ 68:345–353

    Article  Google Scholar 

  • Karakus M, Tutmez B (2006) Fuzzy and multiple regression modelling for evaluation of intact rock strength based on point load, Schmidt hammer and sonic velocity. Rock Mech Rock Eng 39(1):45–57

  • Karaman K, Kesimal A, Ersoy E (2014) A comparative assessment of indirect methods for estimating the uniaxial compressive and tensile strength of rocks. Arab J Geosci. doi:10.1007/s12517-014-1384-0

    Google Scholar 

  • Kılıç A, Teymen A (2008) Determination of mechanical properties of rocks using simple methods. Bull Eng Geol Env 67:237–244

    Article  Google Scholar 

  • Kohno M, Maeda H (2012) Relationship between point load strength index and uniaxial compressive strength of hydrothermally altered soft rocks. Int J Rock Mech Min Sci 50:147–157

    Article  Google Scholar 

  • Mishra DA, Basu A (2012) Use of the block punch test to predict the compressive and tensile strengths of rocks. Int J Rock Mech Min Sci 51:119–127

    Article  Google Scholar 

  • Mishra DA, Basu A (2013) Estimation of uniaxial compressive strength of rock materials by index tests using regression analysis and fuzzy inference system. Eng Geol 160:54–68

    Article  Google Scholar 

  • O’Rourke JE (1989) Rock index properties for geoengineering in underground development. Min Eng 106–110

  • Palchik V, Hatzor YH (2004) The influence of porosity on tensile and compressive strength of porous chalks. Rock Mech Rock Eng 37(4):331–341

    Article  Google Scholar 

  • Pells PJN (1975) The use of point load test in predicting the compressive strength of rock material. Aust Geomech G 5(N1):54–56

    Google Scholar 

  • Quane SL, Russell JK (2005) Ranking welding intensity in pyroclastic deposits. Bull Volcano 67:129–143

    Article  Google Scholar 

  • Read JRL, Thornten PN, Regan WM (1980) A rational approach to the point load test. In: Proc 3rd Australian–New Zealand Geomechanics Conf, Wellington, New Zealand, 12–16 May 1980, 2:35–39

  • Romana MR (1999) Correlation between uniaxial compressive and point-load strengths for different rock classes. In: Proc 9th ISRM Congr, Paris, France, 25–28 August 1999, 2:673–676

  • Rusnak J, Mark C (2000) Using the point load test to determine the uniaxial compressive strength of coal measure rock. In: Peng SS, Mark C (eds) Proc 19th Int Conf on Ground Control in Mining, Morgantown, WV, USA, 8–10 Aug 2000, pp 362–371

  • Sabatakakis N, Koukis G, Tsiambaos G, Papanakli S (2008) Index properties and strength variation controlled by microstructure for sedimentary rocks. Eng Geol 97:80–90

    Article  Google Scholar 

  • Santi PM (2006) Field methods for characterizing weak rock for engineering. Environ Eng Geosci XII 1:1–11

    Article  Google Scholar 

  • Singh VK, Singh DP (1993) Correlation between point load index and compressive strength for quartzite rocks. Geotech Geol Eng 11(4):269–272

    Article  Google Scholar 

  • Singh TN, Kainthola A, Venkatesh A (2012) Correlation between point load index and uniaxial compressive strength for different rock types. Rock Mech Rock Eng 45(2):259–264

    Article  Google Scholar 

  • Smith HJ (1997) The point load test for weak rock in dredging applications. Int J Rock Mech Min Sci 34(3–4), Paper 295

  • SPSS (2006) Statistical Package for the Social Sciences, SPSS v.15.0 for Windows. SPSS Inc., Chicago

  • Sulukcu S, Ulusay R (2001) Evaluation of the block punch index test with particular reference to the size effect, failure mechanism and its effectiveness in predicting rock strength. Int J Rock Mech Min Sci 38:1091–1111

    Article  Google Scholar 

  • Thuro K, Plinninger RJ (2001) Scale effects in rock strength properties. Part 2: Point load test and point load strength index. In: Proc ISRM Reg Symp Eurock 2001, Espoo, Finland, 4–7 June 2001, pp 175–180

  • Topal T (2000) Problems faced in the applications of the point load index test (in Turkish). J Geol Eng 24(1):73–86

  • Tsiambaos G, Sabatakakis N (2004) Considerations on strength of intact sedimentary rocks. Eng Geol 72:261–273

    Article  Google Scholar 

  • Tugrul A, Zarif IH (1999) Correlation of mineralogical and textural characteristics with engineering properties of selected granitic rocks from Turkey. Eng Geol 51:303–317

    Article  Google Scholar 

  • Turk N (1989) A new procedure for determination of point load strength of rocks. Bull Eng Geol 10:25–31

    Google Scholar 

  • Turk N, Dearman WR (1986) A new procedure for determination of point load strength in site investigation. Eng Geol Spec Pub 6:405–411

    Google Scholar 

  • Ulusay R, Hudson JA (eds) (2007) The complete ISRM Suggested Methods for rock characterization, testing and monitoring. Suggested Methods prepared by the Commission on Testing Methods, International Society for Rock Mechanics. ISRM Turkish National Group, Ankara, p 628

  • Vallejo LE, Welsh RA, Robinson MK (1989) Correlation between unconfined compressive and point load strength for Appalachian rocks. In: Proc 30th US Symp Rock Mech, Morgantown, WV, USA, 19–21 June 1989, pp 461–468

  • Zarif IH, Tugrul A (2003) Aggregate properties of Devonian limestones for use in concrete in Istanbul, Turkey. Bull Eng Geol Env 62:379–388

    Article  Google Scholar 

Download references

Acknowledgments

The authors would like to express their sincerest gratitude to the editor and reviewers for their invaluable comments, and Miss. Brittany Lock from the EF Education First Language School in the UK for improving the language used in the manuscript.

Author information

Authors and Affiliations

  1. Department of Geological Engineering, Faculty of Engineering, Recep Tayyip Erdogan University, 53100, Rize, Turkey

    Ayberk Kaya

  2. Department of Mining Engineering, Faculty of Engineering, Karadeniz Technical University, 61080, Trabzon, Turkey

    Kadir Karaman

Authors
  1. Ayberk Kaya
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Kadir Karaman
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to Ayberk Kaya.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kaya, A., Karaman, K. Utilizing the strength conversion factor in the estimation of uniaxial compressive strength from the point load index. Bull Eng Geol Environ 75, 341–357 (2016). https://doi.org/10.1007/s10064-015-0721-1

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10064-015-0721-1

Keywords

Search

Navigation