Point Load Strength Index of Half-Cut Core Specimens and Correlation with Uniaxial Compressive Strength

Şahin, Merve Büke; Ulusay, Reşat; Karakul, Hasan

doi:10.1007/s00603-020-02137-9

Cited by 24 publications

(14 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…UCS tests require numerous samples, and these must be accurately extracted and transported to the laboratory to be prepared with the dimensions required by standards. Alternatively, UCS can be determined by means of other laboratory tests such as the point load test (PLT) (Galvan et al 2014;Şahin et al 2020), Schmidt hardness test (SH) (Aydin 2009;Sabatakakis et al 2008), Leeb rebound hardness test (LHT) (Corkum et al 2018;Meulenkamp and Alvarez Grima 1999;Verwaal and Mulder 1993;Yilmaz 2013) and the needle penetration test (NPT) (Rabat et al 2020) which provide quicker, cheaper and sufficiently reliable results.…”

Section: Introductionmentioning

confidence: 99%

“…These correlations can provide a fast and cost-effective estimation of parameters using simple tests. Numerous authors have presented correlations between PLT and HLD, with UCS-derived parameters (Bieniawski 1975;Broch and Franklin 1972;Deere and Miller 1965;Şahin et al 2020), but little research is available on strength prediction for rocks exposed to high temperatures. Predictors in most cases are physical properties such as mineral grain characteristics (Armaghani et al 2016;Gokceoglu and Zorlu 2004;Vagnon et al 2021), density, porosity and wave velocity (Martínez-Ibáñez et al 2021a, b;Singh et al 2017;Singh et al 2001;Sonmez et al 2006;Sonmez et al 2004;Yesiloglu-Gultekin et al 2013;Zorlu et al 2008).…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Predicting the Uniaxial Compressive Strength of a Limestone Exposed to High Temperatures by Point Load and Leeb Rebound Hardness Testing

et al. 2021

View full text Add to dashboard Cite

The effect of exposure to high temperature on rock strength is a topic of interest in many engineering fields. In general, rock strength is known to decrease as temperature increases. The most common test used to evaluate the rock strength is the uniaxial compressive strength test (UCS). It can only be carried out in laboratory and presents some limitations in terms of the number, type and preparation of the samples. Such constrains are more evident in case of rocks from historical monuments affected by a fire, where the availability of samples is limited. There are alternatives for an indirect determination of UCS, such as the point load test (PLT), or non-destructive tests such as the Schmidt’s hammer, that can also be performed in situ. The aims of this research are: (i) measuring the effect of high temperatures and cooling methods on the strength and hardness of a limestone named Pedra de Borriol widely used in several historic buildings on the E of Spain, and (ii) studying the possibility of indirectly obtaining UCS by means of PLT and Leeb hardness tests (LHT), using Equotip type D. Limestone samples were heated to 105 (standard conditions), 200, 300, 400, 500, 600, 700, 800 and 900 ºC and cooled slowly (in air) and quickly (immersed in water). After that, UCS, PLT and LHT tests were performed to evaluate the changes as temperature increases. Results show decreases over 90% in UCS, of between 50 and 70% in PLT index and smaller than 60% in LHT index. Insignificant differences between cooling methods were observed, although slowly cooled samples provide slightly higher values than quickly cooled ones. The results indicate that LHT can be used to indirectly estimate UCS, providing an acceptable prediction. Research on correlating strength parameters in rocks after thermally treated is still scarce. This research novelty provides correlations to predict UCS in historic buildings if affected by a fire, from PLT and non-destructive methods such as LHT whose determination is quicker and easier.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Predicting the Uniaxial Compressive Strength of a Limestone Exposed to High Temperatures by Point Load and Leeb Rebound Hardness Testing

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Brook [15] considered that the general usefulness of the point load strength test was applying compressive strength estimation, rock mass classification, estimation of triaxial behavior, and small-scale physical model testing. S ¸ahin et al [16] studied the point load strength index of half-cut core specimens and its correlation with uniaxial compressive strength. Fan et al [17] considered that the distance between two loading points and the width of the actual fracture section played an essential and nonnegligible role for the failure of rock specimens.…”

Section: Introductionmentioning

confidence: 99%

“…In recent years, there are many reports on the relationship between them, which are aimed at different types of rocks. ISRM [7], Forster [20], Ghosh and Srivastava [21], Chau and Wong [22], Smith [23], Tsiambaos and Sabatakakis [24], Palchik and Hatzor [25], Singh et al [26], Kohno and Maeda [27], Li and Wong [28], S ¸ahin et al [16], Kaya and Karaman [29], Liu et al [30], Rabat et al [31], Xue et al [32], and Xie et al [33] considered that the two were linear with zero intercept. Andrea et al [9], Ulusay et al [12], Kahrama [34], Diamantis et al [35], Yilmaz [36], Kaya and Karaman [29], Heidari et al [37], and Kong and Shang [38] et al believed that the two are linear relations of non-zero intercept.…”

Section: Introductionmentioning

confidence: 99%

Experimental Study on Mudstone’s Strength Characteristics in Deep‐Buried Coal‐Measure Formation: A Case Study of Permian Longtan Formation

et al. 2021

Shock and Vibration

View full text Add to dashboard Cite

To investigate the strength characteristics of mudstone in deep-buried coal-measure formation, four types of experiments have been conducted: (i) the X-ray diffraction (XRD) test; (ii) the scanning electron microscope (SEM) scanning test; (iii) the point load strength index test; and (iv) the uniaxial compressive strength test. It was concluded that the mudstone of the deep-buried coal measures in the Longtan Formation is dominated by chlorite, quartz, and albite using the XRD test, of which chlorite is primary, accounting for 74.3%. It was found that the three minerals in the mudstone are unevenly distributed using the SEM scanning test, albite is irregularly distributed in chlorite, and quartz is present in the albite and chlorite. Sixty-five specimens were tested for the point load strength index. After processing the data using the method suggested by the International Society for Rock Mechanics and Rock Engineering(ISRM), it was found that the maximum value of Is(50) was 6.10 MPa, the minimum is 0.14 MPa, and 53% of the specimens’ Is(50) values are below 2.0 MPa. The RMT-150C rock mechanics testing machine was used to conduct uniaxial compression tests on six specimens. The maximum uniaxial compressive strength (UCS) value is 59.26 MPa, the minimum value is 31.77 MPa, and the average is 45.64 MPa. Linear fitting and logarithmic fitting are carried out for the correlation between UCS and Is(50). The goodness of fit R2 of the linear fitting is 0.863, and that of the logarithmic fitting is 0.919, indicating a strong correlation between them. When it is challenging to make standard specimens, Is (50) can be used to estimate UCS.

show abstract

“…Jamshidi et al [35] suggested a new parameter (PMP) based on physical and mechanical properties of rocks to estemate the brittleness of sandstones and calculated the PMP of sandstones based on the ratio of PLI to porosity. Şahin et al [36] studied on prediction models for the UCS from the PLI on half-cut core samples.…”

Section: Introductionmentioning

confidence: 99%

Investigation of the availability of a new point load test device in characterization of rocks

Akbay

Altındağ

2021

International Advanced Researches and Engineering Journal

View full text Add to dashboard Cite

Difficulties in determining rock properties have led to the developed and increased use of index test methods predicting them. Index test methods are mostly simple, cheap, and easy to apply but there are some restrictions due to these specifications. The most used method to determine the strength values of rocks indirectly is the point load index. The main aim of this study is primarily investigating the usability of modified test device instead of classical test device. For this, laboratory tests were carried out on rocks with different strength values (3 igneous, 1 metamorphic, 3 sedimentary). The point load index tests were carried on 15 different classical test devices and on a modified test device which the limitations of the classical test device were eliminated. Analysis of the obtained results was carried out by the simple regression method. It was determined the modified test device can be used reliably instead of the classical test devices. Besides, while determining the strength tests the stress distributions on the samples were examined with the finite element method.

show abstract

Point Load Strength Index of Half-Cut Core Specimens and Correlation with Uniaxial Compressive Strength

Cited by 24 publications

References 17 publications

Predicting the Uniaxial Compressive Strength of a Limestone Exposed to High Temperatures by Point Load and Leeb Rebound Hardness Testing

Predicting the Uniaxial Compressive Strength of a Limestone Exposed to High Temperatures by Point Load and Leeb Rebound Hardness Testing

Experimental Study on Mudstone’s Strength Characteristics in Deep‐Buried Coal‐Measure Formation: A Case Study of Permian Longtan Formation

Investigation of the availability of a new point load test device in characterization of rocks

Contact Info

Product

Resources

About