Strength classification of some nigerian limestones using the point load testing technique

  • A. E. Edet
  • S. C. Teme


The point load testing machine has been used to establish certain strength relationships obtained from the results of tests carried out on irregular lump specimens of some Nigerian limestones. The parameters used in the derivations of the relationships include the point load strength index (Is), shape factor (L/D), specimen thickness and the reduction ratio.

The methods of rock classification by Deere and Miller and that proposed by Turk and Dearman have been slightly modified for the purpose of rock classification in the field.

Based on the intact strength and Rock Mass Rating, the rock mass quality of some limestones from Southern Nigeria have been estimated.


Nigeria Uniaxial Compressive Strength Point Load Reduction Ratio Strength Index 

Classification de quelques calcaires du nigéria à partir de l'essai de résistance au fendage sous charge ponctuelle


L'essai de résistance au fendage sous charge ponctuelle a été utilisé pour tester la résistance d'échantillons irréguliers de calcaires nigérians. Les paramètres utilisés incluent l'indice de résistance au fendage sous charge ponctuelle Is, le coefficient de forme (L/D) l'épaisseur de l'échantillon et le coefficient de réduction.

Pour la classification des roches sur le terrain, les méthodes proposées par Deere et Miller et celles proposées par Turk et Dearman ont été légèrement modifiées.


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Copyright information

© International Association of Engineering Geology 1990

Authors and Affiliations

  • A. E. Edet
    • 1
  • S. C. Teme
    • 2
  1. 1.Department of GeologyUniversity of CalabarCalabarNigeria
  2. 2.Institute of Flood, Erosion, Reclamation and TransportationRivers State University of Science and TechnologyPort HarcourtNigeria

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