1 USING THE POINT LOAD TEST TO DETERMINE THE UNIAXIAL COMPRESSIVE STRENGTH OF COAL MEASURE ROCK John Rusnak, Director of Geology Peabody Group St. Louis, MO Christopher Mark, Rock Mechanics Team Leader National Institute for Occupational Safety and Health Pittsburgh, PA ABSTRACT Point load testing is used to determine rock strength indexes in geotechnical practice. The point load test apparatus and procedure enables economical testing of core or lump rock samples in either a field or laboratory setting. In order to estimate uniaxial compressive strength, index-to-strength conversion factors are used. These factors have been proposed by various researchers and are dependent upon rock type. This study involved the extensive load frame and point load testing of coal measure rocks in six states. More than 1, individual test results, from 98 distinct rock units, were used in the study. Rock lithologies were classified into general categories and conversion factors were determined for each category. This allows for intact rock strength data to be made available through point load testing for numerical geotechnical analysis and empirical rock mass classification systems such as the Coal Mine Roof Rating (CMRR). INTRODUCTION is sufficient. This is due in part to the high variability of UCS measurements. Moreover, the tests are expensive, primarily because of the need to carefully prepare the specimens to ensure that their ends are perfectly parallel. THE POINT LOAD TEST The PLT is an attractive alternative to the UCS because it can provide similar data at a lower cost. The PLT has been used in geotechnical analysis for over thirty years (ISRM, 1985). The PLT involves the compressing of a rock sample between conical steel platens until failure occurs. The apparatus for this test consists of a rigid frame, two point load platens, a hydraulically activated ram with pressure gauge and a device for measuring the distance between the loading points. The pressure gauge should be of the type in which the failure pressure can be recorded. A state of the art point load testing device with sophisticated pressure reading instrumentation is shown in Figure 1. The point load test (PLT) is an accepted rock mechanics testing procedure used for the calculation of a rock strength index. This index can be used to estimate other rock strength parameters. The focus of this paper is to present the data analysis used to correlate the point load test index (Is 5 ) with the uniaxial compressive strength (UCS), and to propose appropriate Is 5 to UCS conversion factors for different coal measure rocks. The rock strength determined by the PLT, like the load frame strengths that they estimate, are an indication of intact rock strength and not necessarily the strength of the rock mass. THE UNIAXIAL COMPRESSIVE STRENGTH TEST The UCS is undoubtedly the geotechnical property that is most often quoted in rock engineering practice. It is widely understood as a rough index which gives a first approximation of the range of issues that are likely to be encountered in a variety of engineering problems including roof support, pillar design, and excavation technique (Hoek, 1977). For most coal mine design problems, a reasonable approximation of the UCS Figure 1. The Point Load Tester.
2 The International Society of Rock Mechanics (ISRM, 1985) has established the basic procedures for testing and calculation of the point load strength index. There are three basic types of point load tests: axial, diametral, and block or lump. The axial and diametral tests are conducted on rock core samples. In the axial test, the core is loaded parallel to the longitudinal axis of the core, and this test is most comparable to a UCS test. The point load test allows the determination of the uncorrected point load strength index (Is). It must be corrected to the standard equivalent diameter (De) of 5 mm. If the core being tested is "near" 5 mm in diameter (like NX core), the correction is not necessary. The procedure for size correction can be obtained graphically or mathematically as outlined by the ISRM procedures. The value for the Is 5 (in psi) is determined by the following equation. Is 5 = P/De 2 (1) P = Failure Load in lbf (pressure x piston area). De = Equivalent core diameter (in). As Hoek (1977) pointed out, the mechanics of the PLT actually causes the rock to fail in tension. The PLT s accuracy in predicting the UCS therefore depends on the ratio between the UCS and the tensile strength. For most brittle rocks, the ratio is approximately 1. For soft mudstones and claystones, however, the ratio may be closer to 5. This implies that PLT results might have to be interpreted differently for the weakest rocks. Early studies (Bieniawski, 1975; Broch and Franklin, 1972) were conducted on hard, strong rocks, and found that relationship between UCS and the point load strength could be expressed as: UCS = (K) Is 5 = 24 Is 5 (2) Where K is the "conversion factor." Subsequent studies found that K=24 was not as universal as had been hoped, and that instead there appeared to be a broad range of conversion factors. Table 1 summarizes published results obtained for sedimentary rocks. Most of the estimates place the conversion in a range between 16 and 24, with even lower values for some shales and mudstones. In studies comparing the PLT with the UCS, it is generally assumed the UCS test is the standard. In reality, however, UCS tests provide an estimate of the true UCS of the rock. The accuracy of the estimate depends on the natural scatter in the UCS test results (indicated by the standard deviation (SD)) and the number of tests conducted (n). This relationship is captured by the concept of the Confidence Interval (CI). For normally distributed data, the 95% CI of the mean is expressed as: CI 95% = 196. SD n (3) Table 1. Published comparisons between the point load and uniaxial compressive strength tests for sedimentary rock. Reference Rock Type Location Number of tests Conversion Factor Comments Das, 1995 Siltstone Western Canada, bituminous coalfields NG lumps, fresh core, old core Sandstone/siltstone NG 18 Shale/mudstone NG 12.6 Vallejo et al, 1989 Sandstone Eastern KY, VA, WV 42 PLT, 21 UCS 17.4 Freshly blasted rock, irregular lump samples Shale surface coal mines 1,1 PLT, 55 UCS 12.6 Smith, 1997 Dredge material various harbors NG 8 UCS<1 psi Dredge material various harbors NG 15 UCS<35 psi sandstone/limestone unk NG 24 UCS>6 psi Broch and Franklin, 1972 Various UK (?) NG rock types Carter and Sneddon, 1977 Coal measure UK 1, PLT, 68 UCS units tested O'Rourke, 1988 Sedimentary Paradox Basin, US 66 3 samples from one borehole Hassani et al., 198 Sedimentary UK 1, 29 Singh and Singh, 1993 Quartzite India, copper pit Read et al, 198 Sedimentary rocks Melbourne, Australia NG 2 Reference in Choi and Hong, 1998 Bieniawski, 1975 Sandstone South Africa Rusnak, 1998 Coal measure Southern WV Subset of current data Jermy and Bell, 1991 Coal measure South Africa NG 14.1 Mainly sandstones 1 NG=Not given in reference
3 In general, the variability in the PLT-UCS relationship can be attributed to three sources: 1. Inaccuracy in the estimate of the true UCS obtained from UCS tests. 2. Inaccuracy in the estimate of the true PLT obtained from PLT tests. 3. Real differences between the two tests. Many of the studies summarized in Table 1 compared a suite of point load tests to a single UCS test. With such an experimental design, much of the scatter in the results might actually be attributable to the inaccuracy of the UCS tests. PEABODY ROCK MECHANICS DATA Peabody established an in house rock mechanics testing facility in the fall of This facility is located in Freeburg, IL. A full range of equipment was purchased to perform tests including uniaxial compressive strength, indirect tensile strength, point load index, triaxial compressive strength, flexural strength, direct shear strength, long term creep, roof bolt anchorage capacity, slake durability, ultrasonic velocity, swelling strain and Atterberg limits. The diametral point load (DPL) was not initiated until 1996, which resulted from an interest in utilizing of the Coal Mine Roof Rating (CMRR). ASTM and ISRM procedures are followed for all rock mechanics testing. This testing has been done primarily on core samples obtained from exploration drilling to provide data for mine planning and design. The Freeburg facility was eventually sold to Standard Laboratories in 1991 who continue to operate it. The majority of the data analyzed in this paper was from the testing done at Freeburg. After 1997, all West Virginia testing has been carried out at Commerical Testing and Engineering's facility in Beckley, WV. Currently, the data base contains rock mechanics test results from 914 drill holes from the states of THE UCS AND PLT DATA BASE DESCRIPTIVE STATISTICS The methodology used in the selection of core samples for testing was as follows: 1. Within each hole, rock units were identified where a sequence of tests had been performed with an identical geologic description and no major gaps in elevation. 2. Rock units with at least 3 UCS and 3 PLT results were selected for inclusion in the data base. 3. The mean UCS, mean Is 5, the standard deviations, and the CI 95 were calculated for each rock unit. The samples were also categorized into rock type based on the geologic description. These rock types correspond to the Ferm Classification numbers. Ferm and Weisenfluh (1981) developed a number system classification for coal measure rock types using color photographs of rock core in an index guide. It as been widely accepted as a means for consistent rock identification and for use in computer data bases of drilling information. The categories of rock types and their Ferm classification numbers used in this data analysis are as follows: Rock Type Ferm Series Shale and Claystone 1-2 Silty or Sandy Shale 3-4 Sandstone 5-7 Of the original 36, tests, more than 1, from 98 rock units were retained for the analysis. The distribution of the units and representative values are reported in Table 2. The median of the means is reported, rather than the mean of the means, to reduce the influence of outliers. All the statistical analysis was performed using SPSS version 1. Figure 3 compares UCS determined for different rock types in different regions. One striking observation is that the rocks from the Midwest (IN, IL, and western KY) are significantly weaker than their counterparts from WV (a fact confirmed by ANOVA). Figure 4a shows the range of standard deviations for the UCS tests, expressed as a fraction of the mean UCS. The standard deviations are greatest for limestones and shales, with the median SD about 35% of the mean. The median standard deviations for siltstones and sandstones are about 19% of the mean. Figure 2. Location of the drillholes from which the samples were obtained. WV, IL, KY, IN, CO, and OH. Most of the core was NX-size with some 75-mm (3-in) diameter. A map showing the distribution of the drilling is shown below (figure 2). Table 2 also reports the median Is 5 and SD of Is 5. Expressed as a percent of the mean, the median standard deviation for the Is 5 ranges from 2% for sandstone to 35% for shale. As figure 4b confirms, the variability of the PLT is similar to that of the UCS test, as has been reported elsewhere (ISRM, 1985).
4 Count Count Table 2. Summary of the data used in this study. Rock type Location N units N UCS Median Median SD of Median Median SD N PLT tests tests UCS UCS Is 5 of Is 5 All states 289 1, ,664 1, Shale Midwest 29 1,72 4,367 1,314 1, West Virginia ,752 2, All states 296 1,557 6,286 1,166 1, Siltstone Midwest 236 1,275 5,931 1,27 1, West Virginia ,332 2, All states 228 1,591 1,931 2,96 1, Sandstone Midwest ,773 1, West Virginia ,574 2, Limestone Midwest ,752 6, All states All states 98 5,139 7,4 1,796 5, N - Number of tests. UCS - Unconfined compressive strength (psi). SD - Standard deviation (psi) Is 5 - Point Load Index. 35 SHALE SILTSTONE UNIAXIAL COMPRESSIVE STRENGTH ( UCS,psi) SHALE SILTSTONE SANDSTONE LIMESTONE REGION 75 th % Median 25 th % Midwest W.V a SANDSTONE LIMESTONE ROCK TYPE 75 Figure 3. Range of uniaxxial compressive strengths found in the data base Standard Deviation of Is 5 (Compared with the mean) Figure 4b. Histograms of standard deviations, Point Load Test. Figure 4a. Histograms of standard deviations, Uniaxial Compressive Strength. The Is 5 values obtained from this study are compared with data reported by Molinda and Mark (1996) in table 3. Molinda and Mark s data was obtained from throughout the US and includes a high percentage of tests from southern WV. Table 3 reports means of the mean Is 5 values to make the results comparable. It can be seen that the two studies found similar results.
5 Table 3. Comparison between PLT data from this study and that presented by Molinda and Mark (1996). Rock Type Average, this study Is(5) (psi) Midwest, this study WV, this study Molind a & Mark Shale Sandy Shale Sandstone SUMMARY OF THE REGRESSION ANALYSIS A linear regression between the mean Is 5 and mean UCS values determined for all 98 units yielded the following equation: Equation 4 contains an intercept, however, unlike the traditional form of the UCS-PLT relationship (equation 3). Unfortunately, the r 2 obtained from a zero-intercept regression is not comparable to the standard r 2. Therefore a different measure of the validity of the result must be used. For this study, the validity measure was defined as the percent of mean Is 5 values that fall within the 95% CI of the corresponding UCS. In addition, the percent of mean Is 5 values falling 1 and 2 MPa (1,5 and 3, psi) from the 95% CI of the mean UCS were also calculated. The zero-intercept regression equation obtained from the entire data set is: UCS = 21. Is 5 (5) UCS = Is 5 (4) The correlation coefficient (r 2 ) obtained for equation 4 is.68, which is not bad for rock mechanics. The regression equation simply uses the pairs of means, without regard to the associated standard deviations. Therefore, the r 2 for equation 4 implies that the point load test explains two-thirds of the variability in the UCS, with one-third attributable to the three potential sources of scatter listed earlier. With this equation, 5.4% of the predicted UCS values fall within the 95% CI of the measured UCS. Only 8.5% of the predicted values are more than 2 MPa away from the 95% CI (figure 5). For equation 4, the regression equation with an intercept, 49.% of the predicted values were within the 95% CI and 7.6% were more than 2 MPa away. It seems that the zero-intercept equation is just as accurate as the standard regression equation that includes an intercept. 5 ACCURACY OF REGRESSION EQUATIONS 4-1, -8, -6, -4, -2, 2, 4, 6, 8, 1, NUMBER OF UNITS 12, DISTANCE FROM 95% ci (psi) Figure 5. Histogram 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.
6 Table 4 shows the conversion factors (K) obtained from zero-intercept regression analyses on various subsets of the data. Nearly all the K values lie between 2 and 22, regardless of rock type or geographic origin. Figures 6a-6e shows the regression equation (equation 5) mapped on the different data subsets. Table 4. Conversion factors (K) obtained from zero-intercept regression analysis. Rock type Location K All states 21.8 Shale Midwest 22.4 West Virginia 2.2 All states 2.2 Siltstone Midwest 19.6 West Virginia 2.8 All states 2.6 Sandstone Midwest 2.2 West Virginia 2.4 Limestone Midwest 21.9 All states All states 21. Finally, the relationship between rock strength and K was explored. There was a slight tendency for the UCS/Is 5 ratio (K i ) to decrease for low UCS rocks. The median K i for the entire data set was 22.7, but that decreased to 16.9 for the subset of rocks whose UCS was less than 2 MPa (3, psi). Unfortunately, a similar trend was not evident in the PLT data, so efforts to adjust K for low Is 5 rocks did not improve overall accuracy. DISCUSSION Several factors are relevant in comparing this study with previous ones. First, the present study involves the largest number of tests, nearly 1 times as many as the next largest study. It also includes a wide variety of rock types from several mining regions, and it explicitly addresses the variability associated with the UCS tests. One disadvantage of the study was that the number of PLT tests averages about 5 per unit. Therefore it was not possible to follow the ISRM (1985) suggested method for determining the mean value, which involves deleting the two highest and two lowest Is 5 values from a suite of at least 1 tests. Finally, it should be noted that in these tests the average moisture content varied from.79% for the shale to.49% for the sandstone. Vallejo et al. (1989) found that K values were greater when the samples were saturated. UNIAXIAL COMPRESSIVE STRENGTH (UCS,psi) ROCK TYPE UCS=21 PIV SHALE SILTSTONE SANDSTONE LIMESTONE ALL DATA POINT LOAD INDEX (Is (5), psi) Figure 6a. Regression between uniaxial compressive strength and point load index. All rock types (a random selection of 4% of the data points is shown).
7 SHALE 3 UNIAXIAL COMPRESSIVE STRENGTH (UCS,psi) POINT LOAD INDEX (Is (5), psi) 25 Figure 6b. Regression between uniaxial compressive strength and point load index. SHale. SILTSTONE UNIAXIAL COMPRESSIVE STRENGTH (UCS,PSI) s POINT LOAD INDEX (IS(5),psi) Figure 6c. Regression between uniaxial compressive strength and point load index. Siltstone.
8 3 SANDSTONE UNIAXIAL COMPRESSIVE STRENGTH (UCS,psi) UNIAXIAL COMPRESSIVE STRENGTH (UCS,psi) POINT LOAD INDEX (Is (5), psi) Figure 6d. Regression between uniaxial compressive strength and point load index. Sandstone. LIMESTONE POINT LOAD INDEX (Is (5), psi) Figure 6e. Regression between uniaxial compressive strength and point load index. Limestone.
9 he conversion factors (K) determined in this study fall in the middle of the range of the studies reported in table 1. They are somewhat greater than the K factors currently used in the CMRR (Mark and Molinda, 1996). Those values, 12.5 for shales and 17.4 for sandstones, were originally proposed by Vallejo et al. (1989). Many of the samples that Vallejo tested came from the same geologic formations included in this study. However, Vallejo tested lump samples rather than the core samples used here, and he compared the results from single UCS tests with suites of PLT tests. Like some other researchers, Vallejo et al. (1989) concluded that K should be smaller for shales than for sandstones. While the current study found some evidence that K was less for the weakest rocks (not just shales), it was difficult to identify those rocks from the PLT measurements alone. Therefore, using different K values may not be justified for axial PLT tests. However, diametral tests often give Is 5 values that are much lower than those from axial tests. Converting diametral test results using the same K value is likely to be inaccurate. It is also unnecessary, because diametral tests are used as an indirect measure of bedding plane cohesion, not rock strength (Mark and Molinda, 1996). It is probably more sensible to report Is 5 from diametral tests directly. CONCLUSION The PLT is an efficient method to determine intact rock strength properties from drill core samples. It has become an accepted test in geotechnical evaluations. This study found that a conversion factor K=21 worked well for a variety of rock types and geographic regions. The variability of the PLT, as measured by the standard deviation, was no greater than that of the UCS test. There is some indication that K decreases for lower strength rocks, but the tendency was not very pronounced. Geologic and engineering judgment should be used when converting PLT results to UCS. It must be remembered that both tests can only be used to estimate intact rock strength and not rock mass strength. The point load test provides for full utilization of data that can be gained from exploration drilling programs. Intact rock strength information can be acquired for use in geotechnical evaluation and design work through numerical modeling and rock mass classification systems. The cost of point load testing is minimal when compared to the overall exploration expense. Point load testing of roof and floor rock core of coal seams that are to be mined by underground methods should be standard procedure in any exploration program. ACKNOWLEDGMENTS The authors wish to thank Peabody Group for permission to utilize the data and present this paper. The conclusions contained here are solely those of the authors and not those of Peabody Group. Also, the authors would like to thank Colin Henkes, Geologist for Peabody Group, who oversees exploration drilling and testing programs in West Virginia, and Angela Abruzzino, statistical assistant at NIOSH in Pittsburgh, who helped prepare the database. REFERENCES Bieniawski ZT. The Point Load Test in Geotechnical Practice. Eng. Geol., Sept., 1975, pp Broch E, Franklin JA. The Point Load Strength Test. Int. Journal Rock Mech. Min. Sci 9, 1972, pp Carter PG, Snedden M. Comparison of Schmidt Hammer, Point Load and Unconfined Compression Tests in Carboniferous Strata. Proceeding of a Conference on Rock Engineering. University of New Castle, Tyne, England, 1977, pp Chau KT, Wong RHC. Uniaxial Compressive Strength and Point Load Strength of Rocks. Int. Journal of Rock Mech. Min. Sci and Geomech., 1996, Vol 33, No. 2, pp Das BM. Evaluation of the Point Load Strength for Soft Rock Classification. Proceeding of the 4 th International Conference on Ground Control in Mining. Morgantown, WV, 1985, pp Ferm JC, Weisenfluh GA. Cored Rocks in the Southern Applachian Coalfields. U.S. Bureau of Mines Contract No.H2328 and No. JO Library of Congress # , 1981, 93 pp. Hassani FP, Whittaker BN, Scoble MJ. Application of the Point Load Index Test to Strength Determination of Rock, Proposals for a New Size Correlation Chart. Proceeding of the 21 st U.S. Symp. on Rock Mech., Rolla, MO, 198. Hoek E. Rock Mechanics Laboratory Testing in the Context of a Consulting Engineering Organization. Int. J. Rock Mech. Min. Sci. and Geomech, Abstract 14, 1977, pp ISRM. International Society of Rock Mechanics Commission on Testing Methods, Suggested Method for Determining Point Load Strength, Int. J. Rock Mech. Min. Sci. and Geomech. Abstr. 22, 1985, pp Jermy CA, Bell FG. Coal bearing strata and the stability of coal mines in South Africa. Paper in Proceedings of the 7th Intl. Cong. on Rock Mech. Intl. Soc. Rock Mech., Aachen, Germany, 1991, pp Mark C, Molinda GM. Rating Coal Mine Roof Strength from Exploratory Drill Core. In the Proceeding of the 15 th International Conference on Ground Control in Mining, Golden CO, 1996, pp Molinda GM, Mark C. Rating the Strength of Coal Mine Roof Rocks. U.S. Bureau of Mines IC 9444, 1996, 36 pp. O'Rourke JE. Rock Index Properties for Geoengineering Design in Underground Development. SME preprint 88-48, 1988, 5 pp. Read JRL, Thornton PN, Regan WM. A Regional Approach to the Point Load Test. Proceeding of the Aust-NZ Geomech. Conference 2, 198, pp Rusnak JA. Application of the Coal Mine Roof Rating, Derived from Drill Core, In the Roof Support Design of a Coal Belt Conveyor Tunnel. Proc. of the 17 th International
10 Conference on Ground Control in Mining, Morgantown, WV, 1998, pp Singh VK, Singh DP. Correlation Between Point Load Index and Compressive Strength for Quartzite Rocks. Geotechnical and Geological Engineering, 1993, 11, pp Smith HJ. The Point Load Test for Weak Rock in Dredging Applications. Int. Journal Rock Mech. Min. Sci 34, No. 3-4, 1997, Paper No Vallejo LE, Walsh RA, Robinson MK. Correlation Between Unconfined Compressive and Point Load Strength for Appalachian Rocks. In the Proceeding of the 3 th U.S. Symposium on Rock Mechanics, 1989, pp
Journal of Applied Mathematics and Physics, 2014, 2, 296-303 Published Online May 2014 in SciRes. http://www.scirp.org/journal/jamp http://dx.doi.org/10.4236/jamp.2014.26035 Estimating Unconfined Compressive
Robert Bertuzzi Pells Sullivan Meynink, Unit G3 56 Delhi Road, North Ryde NSW 2113, Australia 1 BACKGROUND Inherent in any set of rock mass parameters are various assumptions regarding, amongst other things
Prediction of Unconfined Compressive Strength of Limestone Rock Samples Using L-Type Schmidt Hammer Dr. Ramli Nazir Associate Professor, Faculty of Civil Engineering, Department of Geotechnics and Transportation,
Global journal of multidisciplinary and applied sciences Available online at www.gjmas.com 2015 GJMAS Journal-2015-3-2/37-41 ISSN 2313-6685 2015 GJMAS Numerical analysis of boundary conditions to tunnels
Geotechnical Testing Methods II Ajanta Sachan Assistant Professor Civil Engineering IIT Gandhinagar FIELD TESTING 2 1 Field Test (In-situ Test) When it is difficult to obtain undisturbed samples. In case
Compression Test, METHOD OF STATEMENT FOR STATIC LOADING TEST Tension Test and Lateral Test According to the American Standards ASTM D1143 07, ASTM D3689 07, ASTM D3966 07 and Euro Codes EC7 Table of Contents
Validation of Cable Bolt Support Design in Weak Rock Using SMART Instruments and Phase 2 W.F. Bawden, Chair Lassonde Mineral Engineering Program, U. of Toronto, Canada J.D. Tod, Senior Engineer, Mine Design
C. Derek Martin University of Alberta, Edmonton, Canada Why measure in-situ stress? Engineering analyses require boundary conditions One of the most important boundary conditions for the analysis of underground
Empirical Correlation of Uniaxial Compressive Strength and Primary Wave Velocity of Malaysian Granites Goh Thian Lai Doctor, School of Environment and Natural Resources Sciences, Faculty of Science and
DIMENSIONING TUNNEL SUPPORT BY DESIGN METHODOLOGY "INTERACTIVE STRUCTURAL DESIGN" Diseno Estructural Activo, DEA) Benjamín Celada Tamames, Director General, Geocontrol, Madrid Translated from: Taller sobre
Why Surface Mine? By Gene Kitts, Senior Vice President-Mining Services, International Coal Group, Inc. Why do we surface mine in Central Appalachia? It s certainly not because we like the public attention
KWANG SING ENGINEERING PTE LTD 1. INTRODUCTION This report represents the soil investigation works at Aljunied Road / Geylang East Central. The objective of the soil investigation is to obtain soil parameters
SOUTH AFRICAN NATIONAL INSTITUTE OF ROCK MECHANICS CHAMBER OF MINES OF SOUTH AFRICA CERTIFICATE IN ROCK MECHANICS PART 1 ROCK MECHANICS THEORY SYLLABUS Copyright 2006 SANIRE CONTENTS PREAMBLE... 3 TOPICS
Brussels, 18-20 February 2008 Dissemination of information workshop 1 Eurocode 7 - Geotechnical design - Part 2 Ground investigation and testing Dr.-Ing. Bernd Schuppener, Federal Waterways Engineering
Correlation of Joint Roughness Coefficient (JRC) and Peak Friction Angles of Discontinuities of Malaysian Schists Abdul Ghani Rafek Geology Programme, Faculty of Science and Technology, National University
Correlation Between Unconfined Compressive Strength and Indirect Tensile Strength of Limestone Rock Samples Ramli Nazir Associate Professor (Ir. Dr), Faculty of Civil Engineering, Department of Geotechnics
1. Introduction 1.1 Scope of Work The Asian Disaster Preparedness Centre (ADPC) is implementing the project Seismic Hazard and Vulnerability Mapping for Rangamati, Bandarban and Khagrachari Municipality.
Tunnelling and Underground Space Technology 22 (2007) 377 387 Tunnelling and Underground Space Technology incorporating Trenchless Technology Research www.elsevier.com/locate/tust A methodology for evaluation
HS-4210_MAN_09.08 product manual HS-4210 Digital Static Cone Penetrometer Introduction This Manual covers the measurement of bearing capacity using the Humboldt Digital Static Cone Penetrometer (DSCP).
The use of the Mackintosh Probe for site investigation in soft soils A. Fakher 1, M. Khodaparast 1 & C.J.F.P. Jones 2 1 Geotechnical Group, Civil Engineering Department, University of Tehran, PO Box: 11365-4563,
Drained and Undrained Conditions Undrained and Drained Shear Strength Lecture No. October, 00 Drained condition occurs when there is no change in pore water pressure due to external loading. In a drained
In-situ Testing! Insitu Testing! Insitu testing is used for two reasons:! To allow the determination of shear strength or penetration resistance or permeability of soils that would be difficult or impossible
PROCEEDINGS OF THE INTERNATIONAL SYMPOSIUM ON GROUND SUPPORT KALGOORLIE/WESTERN AUSTRALIA/15-17 MARCH 1999 Rock Support and Reinforcement Practice in Mining Edited by Ernesto Villaescusa Western Australian
PERIODICA POLYTECHNICA SER. CIV. ENG. VOL. 50, NO. 2, PP. 171 180 (2006) SHEARING TESTS WITH CONTINUOUSLY INCREASING NORMAL STRESS Balázs VÁSÁRHELYI 1 and Péter VÁN 2 1 Department of Building Mat. & Engng.
CIVL451 Soil Exploration and Characterization 1 Definition The process of determining the layers of natural soil deposits that will underlie a proposed structure and their physical properties is generally
C H A P T E R 5 ALLOWABLE LOADS ON A SINGLE PILE Section I. BASICS 5-1. Considerations. For safe, economical pile foundations in military construction, it is necessary to determine the allowable load capacity
DRIVEN PIPE PILES IN DENSE SAND BYRON BYRNE GEOMECHANICS GROUP THE UNIVERSITY OF WESTERN AUSTRALIA ABSTRACT: Piles are often driven open ended into dense sand with the aim of increasing the ease of penetration
National Aeronautics and Space Administration Lyndon B. Johnson Space Center Houston, Texas 77058 REVISION A JULY 6, 1998 REPLACES BASELINE SPACE SHUTTLE CRITERIA FOR PRELOADED BOLTS CONTENTS 1.0 INTRODUCTION..............................................
INTERNATIONAL JOURNAL OF CIVIL AND STRUCTURAL ENGINEERING Volume 3, No 3, 2013 Copyright by the authors - Licensee IPA- Under Creative Commons license 3.0 Research article ISSN 0976 4399 Reliability of
GCSE HIGHER Statistics Key Facts Collecting Data When writing questions for questionnaires, always ensure that: 1. the question is worded so that it will allow the recipient to give you the information
Design Manual Chapter 6 - Geotechnical 6B - Subsurface Exploration Program 6B-2 Testing A. General Information Several testing methods can be used to measure soil engineering properties. The advantages,
COMPARING THE RMR, Q, AND RMi CLASSIFICATION SYSTEMS PART 1: COMBINING THE INPUT PARAMETERS USED IN THE THREE SYSTEMS by Arild Palmström, Ph.D. RockMass as, Oslo, Norway The main rockmass classification
Northumberland Knowledge Know Guide How to Analyse Data - November 2012 - This page has been left blank 2 About this guide The Know Guides are a suite of documents that provide useful information about
COMPARISON OF CORE AND CUBE COMPRESSIVE STRENGTH OF HARDENED CONCRETE M. Yaqub*, University of Engineering and Technology Taxila, Pakistan M. Anjum Javed, Concordia University, Canada 31st Conference on
International Journal of the Physical Sciences Vol. 6(22), pp. 5133-5140, 2 October 2011 Available online at http://www.academicjournals.org/ijps ISSN 1992-1950 2011 Academic Journals Full Length Research
- an introduction for the practical engineer Parts I, II and III First published in Mining Magazine April, June and July 1966 Evert Hoek This paper is the text of three lectures delivered by the author
DESCRIPTIVE STATISTICS The purpose of statistics is to condense raw data to make it easier to answer specific questions; test hypotheses. DESCRIPTIVE VS. INFERENTIAL STATISTICS Descriptive To organize,
Stress Strain Relationships Tensile Testing One basic ingredient in the study of the mechanics of deformable bodies is the resistive properties of materials. These properties relate the stresses to the
Geological Visualization Tools and Structural Geology Geologists use several visualization tools to understand rock outcrop relationships, regional patterns and subsurface geology in 3D and 4D. Geological
Evaluation of Open Channel Flow Equations Introduction : Most common hydraulic equations for open channels relate the section averaged mean velocity (V) to hydraulic radius (R) and hydraulic gradient (S).
Stress-Strain Behavior in Concrete Overview of Topics EARLY AGE CONCRETE Plastic shrinkage shrinkage strain associated with early moisture loss Thermal shrinkage shrinkage strain associated with cooling
Piezocone tests Test standards and procedures Seismic piezocone June 2006 Av Érico Veríssimo, 901 / 302, 22621 180 Rio de Janeiro, Brasil P +55 21 2486 3386, F +55 21 2491 8974 www.terratek.com.br, firstname.lastname@example.org
Using Excel to Solve Business Problems: Simple Predictive Analytics Curtis Seare Copyright: Vault Analytics July 2010 Contents Section I: Background Information Why use Predictive Analytics? How to use
CEMEX USA - Technical Bulletin 2.1 Proper use of the Rebound Hammer Updated to reflect the changes to ASTM C805 The Rebound Hammer has been around since the late 1940 s and today is a commonly used method
Physics 182 - Fall 2014 - Experiment #1 1 Experiment #1, Analyze Data using Excel, Calculator and Graphs. 1 Purpose (5 Points, Including Title. Points apply to your lab report.) Before we start measuring
(Issued 1 Dec. 1995) C654 CRD-C 654-95 Standard Test Method for Determining the California Bearing Ratio of Soils* 1. Scope. 1.1 This test method is used for determining the California Bearing Ratio (CBR)
Advanced Natural Gas Storage (ANGAS) Project and Verification Tests of Experimental Lined Rock Cavern in Japan Toru Komatsubara THE JAPAN GAS ASSOCIATION Taku Watanabe TOKYO GAS CO.,LTD. Satoshi Murase
Reliability of Estimated Anchor Pullout Resistance Yasser A. Hegazy, M. ASCE 1 Abstract In anchor pullout design, conservative soil and rock shear strength parameters are usually adopted. Presumptive values
SITE INVESTIGATION FACILITIES Drilling Hydraulic rotary & calax drilling rigs100/150mm Diameter boreholes having drilling capacity up to 200m depth. Auger drilling 100/150mm diameter boreholes up to maximum
Nuevas tendencias de la Minería Subterránea profunda Planeación, operación y estabilización del macizo rocoso By Ernesto Villaescusa, PhD Chair in Rock Mechanics WA School of Mines, CRC Mining & Curtin
Why Taking This Course? Course Introduction, Descriptive Statistics and Data Visualization GENOME 560, Spring 2012 Data are interesting because they help us understand the world Genomics: Massive Amounts
Spatial sampling effect of laboratory practices in a porphyry copper deposit Serge Antoine Séguret Centre of Geosciences and Geoengineering/ Geostatistics, MINES ParisTech, Fontainebleau, France ABSTRACT
LABORATORY DETERMINATION OF CALIFORNIA BEARING RATIO STANDARD IS: 2720 (Part 16) 1979. DEFINITION California bearing ratio is the ratio of force per unit area required to penetrate in to a soil mass with
COMMON CORE STATE STANDARDS FOR Mathematics (CCSSM) High School Statistics and Probability Mathematics High School Statistics and Probability Decisions or predictions are often based on data numbers in
American Journal of Engineering Research (AJER) e-issn : 2320-0847 p-issn : 2320-0936 Volume-03, Issue-02, pp-141-147 www.ajer.org Research Paper Open Access A Comparative Analysis of Modulus of Rupture
Workplace Safety and Health Focus on Prevention Conducting a Hazard Risk Assessment Risk Analysis Probability High Medium Low Low Medium Severity High Department of Health and Human Services Centers for
Chapter 4: Data & the Nature of Graziano, Raulin. Research Methods, a Process of Inquiry Presented by Dustin Adams Research Variables Variable Any characteristic that can take more than one form or value.
Descriptive statistics is the discipline of quantitatively describing the main features of a collection of data. Descriptive statistics are distinguished from inferential statistics (or inductive statistics),
Lean Six Sigma Training/Certification Book: Volume 1 Six Sigma Quality: Concepts & Cases Volume I (Statistical Tools in Six Sigma DMAIC process with MINITAB Applications Chapter 1 Introduction to Six Sigma,
Technical Journal of Engineering and Applied Sciences Available online at www.tjeas.com 2013 TJEAS Journal-2013-3-8/697-702 ISSN 2051-0853 2013 TJEAS Relationship between the percentage of clay with liquid
Construction Materials Testing Classes of Test February 2014 Copyright National Association of Testing Authorities, Australia 2014 This publication is protected by copyright under the Commonwealth of Australia
July 14, 2015 1.0 GENERAL BI-DIRECTIONAL STATIC LOAD TESTING OF DRILLED SHAFTS This work shall consist of furnishing all materials, equipment, labor, and incidentals necessary for conducting bi-directional
Infinite Algebra 1 Kuta Software LLC Common Core Alignment Software version 2.05 Last revised July 2015 Infinite Algebra 1 supports the teaching of the Common Core State Standards listed below. High School
Laboratory 8 Fatigue Testing Objectives Students are required to understand principle of fatigue testing as well as practice how to operate the fatigue testing machine in a reverse loading manner. Students
PROCESS STANDARDS To help New Mexico students achieve the Content Standards enumerated below, teachers are encouraged to base instruction on the following Process Standards: Problem Solving Build new mathematical
Guidelines for the Estimation and Reporting of Australian Black Coal Resources and Reserves 2001 Edition (as referred to in the Joint Ore Reserves Committee Code ( The JORC Code ) 1999 edition) Prepared
International Journal of Civil Engineering and Technology (IJCIET) Volume 7, Issue 2, March-April 2016, pp. 117 127, Article ID: IJCIET_07_02_009 Available online at http://www.iaeme.com/ijciet/issues.asp?jtype=ijciet&vtype=7&itype=2
GE 441 Advanced Engineering Geology & Geotechnics Spring 2004 Introduction NOTES on the CONE PENETROMETER TEST The standardized cone-penetrometer test (CPT) involves pushing a 1.41-inch diameter 55 o to
Statistical analysis using Microsoft Excel Microsoft Excel spreadsheets have become somewhat of a standard for data storage, at least for smaller data sets. This, along with the program often being packaged
Bill Burton Albert Einstein College of Medicine email@example.com April 28, 2014 EERS: Managing the Tension Between Rigor and Resources 1 Calculate counts, means, and standard deviations Produce
Proceedings of the XI International Seminar on Mineral Processing Technology (MPT-2010) Editors: R. Singh, A. Das, P.K. Banerjee, K.K. Bhattacharyya and N.G. Goswami NML Jamshedpur, pp. 132 136 CRUSHING
Mathematics Probability and Statistics Curriculum Guide Revised 2010 This page is intentionally left blank. Introduction The Mathematics Curriculum Guide serves as a guide for teachers when planning instruction
The Islamic university - Gaza Faculty of Engineering Civil Engineering Department CHAPTER (2) SITE INVESTIGATION Instructor : Dr. Jehad Hamad Definition The process of determining the layers of natural
Correlation and Regression Scatterplots Correlation Explanatory and response variables Simple linear regression General Principles of Data Analysis First plot the data, then add numerical summaries Look
Vol. XX 2012 No. 4 28 34 J. ŠIMIČEK O. HUBOVÁ NUMERICAL ANALYSIS OF THE EFFECTS OF WIND ON BUILDING STRUCTURES Jozef ŠIMIČEK email: firstname.lastname@example.org Research field: Statics and Dynamics Fluids mechanics
Data Mining Part 2. and Preparation 2.1 Spring 2010 Instructor: Dr. Masoud Yaghini Introduction Outline Introduction Measuring the Central Tendency Measuring the Dispersion of Data Graphic Displays References
Algebra I Overview View unit yearlong overview here Many of the concepts presented in Algebra I are progressions of concepts that were introduced in grades 6 through 8. The content presented in this course
Swinburne University of Technology Centre for Sustainable Infrastructure Swinburne University of Technology is undergoing rapid growth, particularly in the area of engineering research and education. Advanced
Landslide hazard zonation using MR and AHP methods and GIS techniques in Langan watershed, Ardabil, Iran A. Esmali Ouri 1* S. Amirian 2 1 Assistant Professor, Faculty of Agriculture, University of Mohaghegh
Simple Linear Regression in SPSS STAT 314 1. Ten Corvettes between 1 and 6 years old were randomly selected from last year s sales records in Virginia Beach, Virginia. The following data were obtained,
Tensile Testing Laboratory By Stephan Favilla 0723668 ME 354 AC Date of Lab Report Submission: February 11 th 2010 Date of Lab Exercise: January 28 th 2010 1 Executive Summary Tensile tests are fundamental