The capillary transport mechanism has an important role on natural building stones that could be affected by moisture due to atmospheric conditions. Travertine with its natural porous structure is ...more sensitive to water which has a significant impact on durability. One of the important indicators of stone–water interaction is color variations, while natural stones with high capillary water absorption potential are in contact with water due to atmospheric conditions. As far as water absorption is concerned, water absorption by weight (WAW), water absorption by volume (
n
, apparent porosity), and capillary water absorption (CWA) parameters are in close relation with each other. To develop the relationships between capillary water absorption and the other water absorption parameters, regression and artificial neural network (ANN) analyses were performed. Within the scope of this study, the ANN models with three different input structures were established using various input variables in order to determine the relationship between CWA and the other parameters. The results of the different ANN structures of these models have been calculated and evaluated. For this purpose, travertine samples quarried from Denizli region in Turkey were studied. In order to evaluate the model results of regression and ANN methods, statistical performance evaluation parameters, i.e., the coefficient of correlation (CORR), efficiency (
E
), and root mean square error (RMSE), were calculated. In both regression and ANN models, reasonable coefficients of correlation were calculated. The capillary water absorption test is time consuming. The necessary periodical measurements make the process even more impractical. It is known that capillary water absorption is directly correlated with similar water absorption parameters such as water absorption by weight and apparent porosity. In this study, the estimation of capillary water absorption by means of other water absorption parameters is proposed. Moreover, there is no proposed classification in literature for natural stones based on their capillary water absorption. In the final stage of this study, by using the relationships between porosity and capillary water absorption, a capillary water absorption classification was proposed for travertine. Proposed classification consists of five categories and capillary water absorption coefficient which is ranging between very high (>68 g/m
2
s
0.5
) and very low (<1 g/m
2
s
0.5
). It is thought that this study could provide significant advantages in engineering practice and also make contribution to the related literature.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The Leeb hardness test, which is developed for metallic materials, is a practical and precise test method and therefore its use on rock materials has started to increase in recent years. Since there ...is not yet a proposed standard method for determining the Leeb hardness on rocks, it was aimed to determine the variation of Leeb hardness on dry and saturated samples, to determine the optimum number of measurements and to reveal the correlation between the optimum number of measurements and rock properties on 26 rock sample groups. A total of 202 samples were tested both in dry and saturated conditions. Leeb measurements were taken as 20 single impacts on a surface of each sample after that basic physical and uniaxial compressive strength (UCS) values of all samples were determined. According to the results of the study, it was determined that the arithmetic mean of taken ten single impacts measurements on a sample was recommended in general use. In saturated conditions, the hardness values were found lower than the dry conditions in various rates under the control of open porosity values. Correlation equations for the prediction of some physical properties and UCS values of rocks have been proposed. The updated test conditions will allow to more effective use of the test method in rapid quality assessment and material characterization of rocks.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Prediction of physical and mechanical properties of rock materials using rebound-based hardness test methods is widely preferred in many fields of engineering and in the characterization of rock ...materials, because they are non-destructive, practical, and economical. In this study, 40 types of rocks with magmatic, metamorphic, and sedimentary origins, represented by travertine, limestone, marble, dolomite, granite, syenite, dunite, andesite, schist, gabbro, tuff, and ignimbrite were selected. First, dry unit weight (
γ
d
), open porosity (
n
o
), water absorption by weight (
W
AW
), wide wheel abrasion (
W
A
), and uniaxial compressive strength values were determined. After that, Shore C-2 scleroscope (HS
C
), L-type Schmidt hammer (HS
L
), and Leeb (HL
D
) rebound-based hardness tests were carried out on all samples, and then, hardness values by three methods were compared with the obtained parameters. The Leeb hardness test, which is more recent and innovative than the Shore and Schmidt hardness tests, was initially developed for metallic materials. However, the method has become increasingly popular in the determination of hardness of rock materials in laboratory as well as in field. In this study, the Leeb hardness test was found to be more useful due to its quick and precise measurement capabilities compared to Shore and Schmidt hardness tests. The results of the study reveal that the prediction of physical and mechanical properties of rocks can more precisely be determined by the HL
D
method than the HS
L
and HS
C
methods using the proposed equations.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Flexural strength is an important mechanical parameter for natural stones used as surface claddings. This study was carried out to investigate the decrease in flexural strength under the influence of ...weathering by freeze-thaw cycles. Five types of building stones which are granite, marble, micritic limestone, sparitic limestone and travertine were exposed to 14, 28, 56, 84, 120 and 200 freeze-thaw cycles, flexural strength tests were conducted as three and four points flexural strength tests. Results indicated that even if no visible disintegration on samples was monitored, noticeable reductions on ultrasonic P-wave velocity, the Leeb hardness, and flexural strength results were observed after freeze-thaw cycles. Correlation between test results for fresh and weathered samples were presented. In addition, anisotropic properties of sample groups were calculated from ultrasonic P-wave velocity values measured in 3 directions and their increases due to freeze-thaw cycles were determined. The long-term durability of stone groups against freeze-thaw cycles was revealed by half-lives calculated from decay function parameters. A decrease in flexural strength of up to 30 % has been revealed under the influence of weathering.
•300 slab samples were subjected to 200 freeze-thaw cycles and flexural strength reduction due to weathering was revealed.•Anisotropic properties were monitored by ultrasonic wave measurements in three perpendicular directions.•Leeb surface hardness were also used to monitor weathering.•Flexural strength losses were revealed, and decay patterns were proposed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Uniaxial compressive strength (UCS), which is one of the most important engineering properties of natural building blocks, exhibits a decrease at various rates under the effect of freeze–thaw (FT) ...cycles. In this study, practical estimation of UCS loss of 21 groups of carbonate building stones exposed to 4, 7, 10, 14, 20, 28, 35, 56, 70 and 84 FT cycles is aimed by proposed estimation models. In all models, the Leeb hardness (HL
D
), which is practically determined by a dynamic surface hardness test method, was used as major input parameter. Other basic stone properties and number of FT cycles were also used as additional input parameters in developed models. The test results indicated that HL
D
and UCS values decreased up to 13 and 40%, respectively, at the end of 84 FT cycles. Proposed equations are reliable and beneficial in estimation of deteriorated UCS values of carbonate building stones in practical engineering applications and scientific studies.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Determination of the probability of occurrences and return periods of earthquakes are important issues in seismic hazard assessment and they are used in the evaluation of the natural hazards ...including liquefaction, slope failures, etc. Southwest (SW) Anatolian Region is well known with its seismic activity. This study aims to compare two areas with different faulting styles in terms of their seismic activities and the seismic hazard of two areas in SW Anatolia by evaluating the probability of occurrences, of earthquakes related with these fault mechanisms. Study area is divided into two groups as Muğla region and Fethiye–Burdur region due to differences in the fault types. Earthquakes follow Poisson distribution and magnitude–frequency relationships are the common methods in the probability calculations in earthquake engineering. Parameters “a” and “b” are important for these calculations. Calculations show that b parameters are low. Probability of occurrences of even high-magnitude earthquakes are in the range of a time interval important for human society. Our study areas cover both mountainous regions with high slope angles and coastal regions; therefore, earthquakes are likely to trigger both landslides and tsunamis in this region. So civil engineering structures in these regions must be designed properly and required precautions must be taken.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•Böhme and Wide Wheel (Capon) Abrasion test data were correlated.•The effect of physical, hardness, uniaxial compressive strength values on abrasion resistance were investigated.•An abrasion ...classification consisted of three classes was proposed based on Wide Wheel abrasion values.
Abrasion resistance of natural stones is very important in terms of their service life. Böhme abrasion test is commonly used for the characterization of abrasion resistance of rocks. However, this test is impractical due its procedure. In this study, estimation of Wide Wheel abrasion test results, which is more practical and economic method, is aimed. Some physical properties, hardness values, Wide Wheel and Böhme abrasion values and uniaxial compressive strength values of 32 specimens were determined. Consequently, reasonable relationships were proposed for the prediction of Wide Wheel values from other properties and Böhme values. Finally, an abrasion classification consisted of three classes for tested natural stones was proposed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Uniaxial compressive strength is considered one of the most important parameters in the characterization of rock material in rock engineering practice. The study investigated correlations between ...uniaxial compressive strength and point load index, P-wave velocity and Schmidt hardness rebound number together with the effects of core diameter size. A total of 150 core samples at five different diameters (54, 48, 42, 30 and 21 mm) were obtained from sandstone, limestone and cement mortar. Ten saturated samples at each diameter (length:diameter ratio 2:1) were prepared from each of the three materials. The best correlations were found between uniaxial compressive strength and point load or Schmidt hammer values. The closest relationship was observed for the 48 mm diameter cores.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The Wide Wheel is a recent abrasion test method (WA) proposed for building stones. The WA test is carried out by special equipment using abrasive dust on prismatic building stone samples. The purpose ...of this study is providing a methodology for practical estimation of the WA values from dry unit weight (γ), open porosity (PO), P-wave velocity (VP) and uniaxial compressive strength (UCS) values. In the study, test data from previous studies were compiled. Multivariate regression analyses (MLR), Feed Forward Back Propagated (FFBP) and Generalized Regression Neural Networks (GRNN) algorithms of Artificial Neural Networks (ANNs) were employed in the analyses. Equations by MLR analyses to estimate the WA values for 5 models were proposed. Then, FFBP and GRNN analyses were performed, and their prediction performance results were assessed. All five models were determined to be strong enough to be used in practice, although FFBP and GRNN are found to be stronger in prediction capability than the MLR method.
•The practical estimation of the abrasion resistance of building stones is an important issue in the selection of natural stones with suitable properties as well as being economical.•The Wide Wheel abrasion values of building stones can be estimated from basic properties as unit weight, open porosity, P-wave velocity, and uniaxial compressive strength.•Equations to estimate abrasion values of building stones were proposed by multivariate regression analyses.•Abrasion values of building stones were successfully modeled by Feed Forward Back Propagated and Generalized Regression algorithms of Artificial Neural Networks method which is commonly used soft computing technique in various fields of science and engineering.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Natural building stones, used as floor cladding stones in outdoor applications in cold regions, are negatively affected by freezing and thawing processes, and this reduces the service life of the ...stone. The aim of this study is to reveal the change of abrasion resistance of natural stones determined by the wide wheel abrasion test (
W
A
) with laboratory freeze–thaw (FT) tests. For this purpose, FT tests were applied up to 84 cycles on 23 groups of samples, mainly consisted of carbonate rocks. According to the results, no significant decrease was determined in the dry unit weight (
γ
d
) value, but significant decreases were obtained in open porosity (
n
) and P-wave velocity (
V
P
) values. It has been revealed that
W
A
values are also significantly affected by increasing FT cycles and increased up to about 14%. It was concluded that the increase was evident up to 35 FT cycles, and after this level, the increase continued with a decrease.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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