The estimation of uniaxial compressive strength conversion factor of trona and interbeds from point load tests and numerical modeling

2017 ◽  
Vol 131 ◽  
pp. 71-79 ◽  
Author(s):  
H. Ozturk ◽  
M. Altinpinar
Author(s):  
Seyed Morteza Davarpanah ◽  
Mohammad Sharghi ◽  
Abolfazl Tarifard ◽  
Ákos Török ◽  
Balázs Vásárhelyi

AbstractThe mechanical properties of frozen rocks vary significantly from the properties of the same lithology under ambient temperature. The goal of this paper is to investigate these changes in the physical and mechanical properties of rocks due to saturation and freezing. Besides, the attention was paid on discovering new correlations between the mechanical characteristics. To fulfill these objectives, 36 uniaxial compressive strength tests, 36 Brazilian splitting tests, and 48 point load tests were carried out. The samples were tested in air dry, water saturated, and frozen (− 20 °C) conditions. The measured physical and mechanical parameters were analyzed by using regression analyses. It was found that the average uniaxial compressive strength of frozen samples (21.93 MPa) is 86.4% more than saturated ones (11.76 MPa) but 25.9% less than dry specimens (29.62 MPa). Additionally, high correlations were established between uniaxial compressive strength and IS(50) under air-dry, saturated, and frozen conditions for the investigated marl samples. Furthermore, it is of particular interest to observe a high correlation with the determination coefficient (R2 = 0.95) between the constants of previously published linear regressions of UCS- Is(50) under dry status.


2020 ◽  
Vol 17 (2) ◽  
pp. 1059-1069
Author(s):  
Mohd Firdaus Md Dan ◽  
Edy Tonnizam Mohamad ◽  
Ibrahim Komoo ◽  
Aziman Madun ◽  
Siti Norsalkini Mohd Akip Tan

Engineering properties of tropical weathered granite mass have been widely investigated and classified for engineering purposes. However, the engineering properties of tropical boulder in weathered granite profile is poorly understood and not well classified. This study aims to examine and classify the physico-mechanical properties of granite boulder in completely weathered zone. A total of 34 in-situ boulders were examined from two granite quarries located in Southern Johor, Malaysia. Microstructure-mineralogical alterations were analyzed based on petrographic analysis and scanning electron microscopy (SEM). The mechanical properties were including dry density, porosity, point load strength, uniaxial compressive strength and permeability. Three properties were identified as significant indicators to differentiate between tropical boulder and completely weathered granite when it is evaluated from the soil investigation drilling work namely; texture characteristics, discolourations and degree of weathering. Analysis revealed that the alteration of microstructures and minerals such as feldspar, biotite, and plagioclase from corestone (Grade I/II) to saprolite (Grade IV/V) zone were significantly reduced the dry density, point load strength, uniaxial compressive strength and permeability with 32%, 99.5%, 98.6% and 84.8%, respectively. It has also significantly increased the porosity up to 11.6 times or 1065% from corestone to saprolite. The significant different of physico-mechanical properties of material surrounding boulder due to weathering can be classified and useful in evaluation of geotechnical design and geological engineering applications.


2013 ◽  
Vol 824 ◽  
pp. 86-90 ◽  
Author(s):  
B. Adebayo ◽  
A.E. Aladejare

The effect of rock properties on excavation-loading operation in quarries was investigated by conducting test on the mechanical properties of selected rocks. These rock samples were tested in the laboratory for specific gravity, point load strength, uniaxial compressive strength and mineral composition using weigh balance, point load tester, 1100kN compression machine and petrological microscope respectively. The filling rates of the front end loaders bucket were determined. The result obtained show that value of uniaxial compressive strength varied from 29.22 MPa-30.87 MPa. The bucket filling rate varied from 0.180-0.250 m3/s and 0.145-0.170 m3/s for porphyritic biotite granite and coarse biotite granite respectively. There is strong relationship between bucket filling rate and strength properties with values of R2 ranging from 0.9737 to 0.9981.Therefore strength parameters of the rock have effect on excavation loading operation in quarries.


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