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Correlations of Uniaxial Compressive Strength and Modulus of Elasticity with Point Load Strength Index, Pulse Velocity and Dry Density of Limestone and Sandstone Rocks in Sulaimani Governorate, Kurdistan Region, Iraq.

Hyam Saleh Daoud1, Kamal Ahmad Rashed2 &Younis M. Alshkane3

1Irrigation Department, Faculty of Engineering, University of Sulaimani, Kurdistan Region, Iraq
Civil Department, Faculty of Engineering, University of Sulaimani, Kurdistan Region, Iraq
Civil  Department, Faculty of Engineering, University of Sulaimani, Kurdistan Region, Iraq

Original: 15 October 2016,  Revised: 1 April 2017,  Accepted: 16 May 2016,  Published online: 20 September 2017


The Uniaxial Compressive Strength (UCS) of rocks is important parameter in design of geotechnical engineering. If the rocks are affected by weathering agents, there will be difficult to obtain intact samples and to determine UCS in laboratory.Hence, the use of another engineering index of rocks as an alternative for determining UCShave been studied and investigated by researchers. The Pulse Velocity and Point Load tests are used as a quick, easy and non-expensive means of obtaining rock strength indexes. This paper presents an experimental study for correlating between Uiaxial Compressive Strength (UCS) and Point Load Index (PLI), Pulse Velocity (Vp), Dry Density andModulus of Elasticity (E) of limestones and sandstone rock samples. 80 specimens of limestones were obtained from Pila Spi and Lower Fars Formations and 46 specimens of sandstone were obtained from Tanjero  ormation. Based on the results, for the first time in this region, a new good correlation is introduced to estimate the UCS and Efrom Pulse Velocity, Point Load Index and Dry Density.

KeywordsUniaxial compressive, Strength; Point load, Index; pulse velocity; limestone; sandstone; strength correlation.


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