For example, the PLT to UCS conversion factor can vary from as low as 8 to as high as 30, while the ITS to UCS conversion factor values vary between 2.7 and 50 [43,44]. This implies that the conversion factor is a rock characteristic parameter and not a universal value; therefore, its applicability must be assessed on a case by case basis.
WhatsApp: +86 18221755073reported by Smith (1997) in which the correlation factor varied between a value of 8 for rocks with UCS of less than 1000 psi (6.9 MPa) to a value of 24 for rock samples with UCS of more than 6000 psi (41.5 MPa). Similar studies (Akram, and Abu Bakar, 2007) showed high differences in correlation factors for the same rock
WhatsApp: +86 18221755073Uniaxial compression strength (UCS) is a fundamental parameter to carry out geotechnical engineering design and construction. It is simple and efficient to predict UCS using point load strength (PLS) at …
WhatsApp: +86 18221755073The distance between the platen was recorded as D, while the failure load as P. Diameter correction for Is 50 was Results and Discussions The laboratory test results of 50 samples of all three Fig. 3 (a) Cutting of core samples (b) prepared samples for UCS (c) prepared samples for PLT and SRHT. tests (UCS, PLT, and SRHT) were taken for the ...
WhatsApp: +86 18221755073The uniaxial compressive strength (UCS) of rock has been recognized as one of the major technical factors of rock-related engineering constructions [1,2,3], and it has also been regarded as the basic parameter of geotechnical engineering designs and constructions [].Moreover, UCS has been used in various aspects of the rock-mass …
WhatsApp: +86 18221755073The main bed rock units of studied area comprises: Sandstone, siltstone claystone, Limestone, dolostone, dolomitic limestone and marl. While the main topographic features are: hill, plateau ...
WhatsApp: +86 18221755073The PLT uses specimens formed by regular and irregular rock fragments or cylindrical specimens [6, 7] (generally from probes) that are not subjected to strict require-ments to be admissible. This test may take place in situ or in the laboratory. This work presents the most appro-priate values correlating PLT and UCS in limestone from
WhatsApp: +86 18221755073Unconfined compressive strength (UCS) is a major mechanical parameter of the rock which has an essential role in developing geomechanical models. It can be estimated directly by lab testing of retrieved core samples or from well log data. These methods are very expensive and require huge efforts and time. Therefore, there is a …
WhatsApp: +86 18221755073Uniaxial compressive strength (UCS) is one of the most important properties of rock that are widely used in geotechnical field. Since, the direct method to obtain UCS is expensive; Point Load Test (PLT) is the most commonly used method to estimate UCS. There are several general conversion factor suggested such as by the ISRM. However, it is found that …
WhatsApp: +86 18221755073The index-to-strength conversion factor was computed as the ratio of UCS over PLT index from the design line. To establish the relationship between PLT index …
WhatsApp: +86 18221755073A conversion factor of carbonate rocks in the linear regression without intercept for UCS–PLI, UCS–BTS, UCS–SHR, and UCS-E was observed as 14.32, 7.26, 1.71, and 3.52, respectively.
WhatsApp: +86 18221755073The UCS can be estimated using the following formula: Where C is a constant that depends on the UCS and I S50 ratio. To correctly derive the value of C both PL and UCS tests must be conducted on the tested material but, if no such data are available, generalized values of C for core samples can be used as shown in Table 1.
WhatsApp: +86 18221755073To use the PLT on blocky fragments to estimate rock strength, it is necessary to find the relation between the point load strength (PLS) of blocky fragments and uniaxial compressive strength (UCS) of surrounding rocks. ... The limestone core samples simultaneously drilled from side wall have an average conversion factor from PLS to …
WhatsApp: +86 18221755073In order to improve the UCS prediction accuracy, 30 sets of regular cylindrical specimen tests between PLS and UCS are conducted on limestone mines. The correlation relationship between PLS and UCS is …
WhatsApp: +86 18221755073Limestone UCS values) with H/D > 1 and typically D <100 mm, correlations need to be established. ... (0.4 to 8 MPa) the conversion factor varies between 0.75 and 0.83. The Standard does not indicate any correction for the diameter per se. ASTM C170 (1989) addresses rectangular cuboid specimens, h by l by w. A conversion factor
WhatsApp: +86 18221755073For limestone, the conversion factor from I s(50) to UCS is considered to be 15–38 (Chau and Wong 1996). The mean value of UCS for the limestone in the present …
WhatsApp: +86 18221755073Shale surface coal mines 1,100 PLT, 55 UCS 12.6 Smith, 1997 Dredge material various harbors NG 8 UCS<1000 psi Dredge material various harbors NG 15 UCS<3500 psi sandstone/limestone unk NG 24 UCS>6000 psi Broch and Franklin, 1972 Various UK (?) NG 23.7 11 rock types Carter and Sneddon, 1977 Coal measure UK 1,000 PLT, 68 UCS …
WhatsApp: +86 18221755073where F is the size correction factor, F = (D e /50) 0.45; I s is the uncorrelated point load strength, MPa; and D e is the "equivalent core diameter" in mm, which is related to the test type. For example, D 2 e = D 2 for diametral tests and D 2 e = 4A/π for axial, block, and lump tests, where A = WD = minimum cross-sectional area of …
WhatsApp: +86 18221755073Histogram showing hte difference between UCS predicted by the PLT using equation 5, and the 95% confidence interval of the measured UCS. The zero bar includes all cases that fell withing the 95% CI. Table 4 shows …
WhatsApp: +86 18221755073Based on this study, in order to convert PLA to UCS values for rocks such as quartz or sandstone and soft rocks such as shale a conversion factor of 21 to 24 and 14 to 16 …
WhatsApp: +86 18221755073and Point Load Index (PLI), and UCS and Schmidt Rebound number (Rn).From these relations, UCS is predictable from PLT and SRHT with a reasonable precision. KEY WORDS-Rock Mechanics, UCS, PLT, Schmidt Rebound Hammer, Sakesar Limestone, UCST for determining UCS is very expensive and regression models I. INTRODUCTION
WhatsApp: +86 18221755073According to (Galvan et al., 2014), the obtained conversion factor for PLT index to UCS range from 12 to 26. However, for conversion factor between point load and uniaxial compressive strength varies from 13 to 29 ... Correlation of rock PLT index with UCS for Limestone and Granitic rock. By extracting data from twenty-two (22) past …
WhatsApp: +86 18221755073Tests easy to perform, as PLT and SHR are also commonly used for indirect determination of UCS. The correlation obtained between UCS and PLT is strong (r = 0.85) (Fig. 21a), similar to the result ...
WhatsApp: +86 18221755073As rock UCS is typically adopted for foundation design purpose, the conversion factor between PLT index and UCS was derived for the typical bedrock formation encountered in Kuala Lumpur, namely Granitic rock and Limestone. This study also depicts the estimation of mobilized rock unit shaft friction with respect to the corresponding UCS value ...
WhatsApp: +86 18221755073Exact copies of PLT and UCS tests can be realistically reproduced, which can help users better understand the construction and working principle of the testing machine. ... The estimation of uniaxial compressive strength conversion factor of trona and interbeds from point load tests and numerical modeling. J Afr Earth Sci, 131 (2017), pp. …
WhatsApp: +86 18221755073The 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 …
WhatsApp: +86 18221755073The implementation has been conducted over 700 field and laboratory tests of which 255 are PLT test, 45 are UCS test, and the rest are other parameters like: porosity and specific weight, Slake ...
WhatsApp: +86 18221755073Kaya and Karaman (2016) obtained conversion factors of PLI to UCS to the tune of 12. 98, 17.68, and 15.32 for pyroclastic, volcanic, and plutonic igneous rocks, 18.55 and 13.51 for chemical...
WhatsApp: +86 18221755073estimate UCS of various rocks through developing simple correlations among the results of uniaxial compressive strength (UCS) and indirect tests on the
WhatsApp: +86 18221755073The point load strength index (Is) was evaluated from Eqs. (6-7) and correlated to UCS by a coefficient factor (Eq. (8)). Rusnak and Mark (1999) had proposed 21.9 as conversion factor for typical ...
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