Last edited by Shagrel
Saturday, August 1, 2020 | History

2 edition of Effect of end conditions on determining compressive strength of rock samples found in the catalog.

Effect of end conditions on determining compressive strength of rock samples

John R. Hoskins

Effect of end conditions on determining compressive strength of rock samples

by John R. Hoskins

  • 36 Want to read
  • 3 Currently reading

Published by U.S. Dept. of the Interior, Bureau of Mines in [Washington, D.C.] .
Written in English

    Subjects:
  • Rocks.,
  • Mining engineering.

  • Edition Notes

    Statementby John R. Hoskins and Frank G. Horino.
    SeriesReport of investigations -- 7171, Report of investigations (United States. Bureau of Mines) -- 7171.
    ContributionsHorino, Frank G., United States. Bureau of Mines
    The Physical Object
    Pagination22 p. :
    Number of Pages22
    ID Numbers
    Open LibraryOL22419011M

    M.R. WISNOM, in Comprehensive Composite Materials, Compressive tests. Compressive testing of composites is notoriously difficult, and despite the huge amount of research that has been undertaken, there are still many problems obtaining reliable and repeatable data for compressive strength. These issues are discussed by Adams in Chapter this volume. Compressive strength is the standard strength parameter of concrete that can be evaluated under site conditions as well. The most common method is to use cylinder cores drilled off the structure. Momber (b) was probably the first to suggest to use the way how a cylinder fails during the compression test as a criterion of the material behaviour during hydrodemolition.

    When using the Brazilian test to determine the indirect tensile strength of rock, it is usually assumed that failure is the result of the uniform tensile stress normal to the splitting diameter (see Figure 4a) and that the tensile strength, T o, is given by the value of F 3 (= -T o) at failureFile Size: KB. The moisture condition of the specimen at the time of the sample preparation can have a significant effect upon the strength and deformation characteristics of the rock. Good practice generally dictates that laboratory tests be made upon a specimens’ representative of field conditions. Thus, it follows that the field moisture condition of the specimen should be preserved until the time.

      TEST PITS It is most satisfactory for determining foundation conditions in rock, since the exposed bed rock surface can be closely inspected. The strength of the rock & ease of excavation can be determine by trial with a pick or compressed-air tools. Blocks or cylinders of the rock can be cut for laboratory tests. It is economical when bed rock. The point load strength index can be used to classify the rocks. A common method used is by estimating the uniaxial compressive strength. 5. Significance and Use The uniaxial compression test (seeTest Method D ) is used to determine compressive strength of rock specimens. However, it is a time-consuming and expensive test thatFile Size: KB.


Share this book
You might also like
An analysis of priorities in marital couples

An analysis of priorities in marital couples

summary of Maryland stream pH and alkalinity data

summary of Maryland stream pH and alkalinity data

Leon Felipe

Leon Felipe

Annual report on exchange arrangements and exchange restrictions 1980.

Annual report on exchange arrangements and exchange restrictions 1980.

tramps note-book.

tramps note-book.

Listening to Heloise

Listening to Heloise

SARA LEE/DE N.V.

SARA LEE/DE N.V.

Rosen and Powerkids Spanish I

Rosen and Powerkids Spanish I

The Federal budget for fiscal year 1984

The Federal budget for fiscal year 1984

Three protests against certain resolutions adopted by the Presbytery of aAntrim, at a special meeting, held on Wednesday, November 6th, 1861

Three protests against certain resolutions adopted by the Presbytery of aAntrim, at a special meeting, held on Wednesday, November 6th, 1861

Bunnies Under Umbrella, Friendship Postcard

Bunnies Under Umbrella, Friendship Postcard

Water rights and water law in the 1980s

Water rights and water law in the 1980s

historical vindication of the abrogation of the plan of union by the Presbyterian Church in the United States of America.

historical vindication of the abrogation of the plan of union by the Presbyterian Church in the United States of America.

Accountability in Hong Kong

Accountability in Hong Kong

University of London union list of serials.

University of London union list of serials.

Effect of end conditions on determining compressive strength of rock samples by John R. Hoskins Download PDF EPUB FB2

Effect of end conditions on determining compressive strength of rock samples. [Washington, D.C.]: U.S. Dept. of the Interior, Bureau of Mines, [] (OCoLC) Laboratory tests were carried out to determine the effect of material discontinuities on rock sample mechanical properties.

The investigations consisted of detecting discontinuities, observing the failure mechanisms during uniaxial compressive strength tests, and analysing of the factors affecting the strength. The Effect of Discontinuities on Strength of Rock Samples.

The mechanical properties of rock samples of identical lithological composition may vary significantly due to existence of material discontinuities. Laboratory tests were carried out to determine the effect of material discontinuities on rock sample mechanical properties.

It can be observed that an increase in the slenderness of specimen caused a decrease in end frictional effect on the uniaxial compressive strength of rock specimen. The numerical results also revealed that the shape effect originated from the end frictional effect as the rock material was homogeneous.

Firstly, the shape effect had the greatest impact on rock strength properties. In the typical range of length/diameter ratios varying from 1 to 3, the influence on destruction work, modulus of elasticity and tensile strength is quite significant.

In comparison, the effect on unconfined compressive strength. A discussion on the decrease of unconfined compressive strength between saturated and dry rock samples M.

Romana Polytechnic University of Valencia, Spain. [email protected] B. Vásárhelyi Technical University of Budapest, Hungary ABSTRACT: The unconfined compressive strength (UCS) of a rock is a basic parameter for manyFile Size: KB.

In this survey whether the sample dimensions measured in laboratory have effect on P-wave velocity or not was investigated. Nine different rock groups were used in this study. Six different diameter core samples were prepared from each of the groups. Therefore, a numerical simulation method is required to determine the lateral inertia effect and end friction effect of granite samples, and then the dynamic compressive strength enhancement caused by the lateral inertial effect and end friction effect, respectively, is eliminated from the measured dynamic compressive strength of granite by: 5.

UNIAXIAL COMPRESSIVE STRENGTH C o (x psi) 0 50 SPECIMEN LENGTH L (in.) VARIATION OF COMPRESSIVE STRENGTH WITH SIZE C o = 35 x L In this plot of the size effect on strength, a power function was used to best-fit the experimental data. NOTE, however, that beyond L=36 in. the size effect ceases to be of much consequence.

unconfined compressive strength of rocks (UCS). Since one cannot expect % efficiency of energy transfer from the bit to the rock, one can then replace SE by the term: [3] Rock drillability prediction from in situ determined unconfined compressive strength of rock by V.C.

Kelessidis* Synopsis. Because the compressive strength of rock is one of the most important parameters in rock engineering practices, and the dynamic test method of compressive strength is less complex than that of the tensile strength test (Huang et al., ), the specific problem investigated in this work is the accumulated damage in rocks due to heat-treatment and its effect on the dynamic compressive strength of by: • Strength classification is based on strength of the rock (compressive strength & modulus of elasticity; Table ) • 5 strength classes: A-E based on the overall rock strength; A = very strong, E = very weak (Table ) • Any discontinuities, fractures, bedding planes, etc.

will strongly influence overall strength of the rock. The effect of specimen size on the measured unconfined compressive strength and other mechanical properties has been studied by numerous researchers in the past, although much of this work has been based on specimens of non-standard dimensions and shapes, and Cited by: ingtheuniaxial compressive strength of rock for practical engineering purposes.

Table IVlists the corres-ponding strength ranges for the strength classification of rock ma-terials8. ESTIMATION OF THE TRIAXIAL STRENGTH While determination ofthe uni-axial compressive strength ofrockis a simple matter, this is not true for the collection of the File Size: KB.

Many dynamic events in coal mine are caused by the instability of coal–rock body. In order to study the influence of rock strength on this type of instability, uniaxial compression experiments of rock–coal–rock composite samples with different rock strengths are carried out, and the effect and mechanism of rock strength on the mechanical behavior and fracture mode of the composite Cited by: Effect of length-to-diameter ratio on the unconfined compressive strength of cohesive soil specimens.

In this work, the influence of the length-to-diameter ratio (L/D) on the unconfined compressive strength (UCS) of cohesive soil specimens was assessed.

COMPRESIVE STRENGTH TEST The compressive strength is probably the most widely d d d k i iused and quoted rock engineering parameter. Under uniaxial load conditions the maximum stress that the rock sample can sustain referred as uniaxial compressive strength (σucs or.

Nine concrete beams were created to determine the fracture toughness of the specimens. Results showed that enhancement in the uniaxial compressive strength of the specimens with diame 68, and 72 mm was monotonic as a result of the increased grain size, whereas it took a monotonic but decreasing trend in those 94 mm in diameter.

Table 4D–6 Hardness and unconfined compressive strength 4D–3 Table 4E–1 Line survey data 4E–1 Table 4E–2 Joint set spacing categories 4E–1 Part National Engineering Handbook Engineering Classification of Rock Materials Chapter 4 (–VI–NEH, Amend. 55, January ) 4–v.

Estimating compressive strength. General rock failure criterion can be reduced to a few parameters dependent on lithology (m) and the uniaxial compressive strength (C 0).Lithology is commonly derived during log analysis, so m may be estimated (Table 1).What is needed still is an initial measure of rock strength provided by C 0.

C 0 can be estimated from porosity or sonic velocities, but many. Coal Operators’ Conference The University of Wollongong 12 –14 February EFFECT OF DIFFERENT CURING CONDITIONS ON THE COMPRESSIVE AND FLEXURAL PROPERTIES OF PLASTER OF PARIS Zhenjun Shan,1Ian Porter, Jan Nemcik and Qiuqiu Qiao ABSTRACT: Gypsum plaster is often used when modelling rock and rock such, it is important that the.

This Video shows a new device and method to determine the unconfined compressive strength (σc) of samples of disc-shaped rocks and which were tested with a diametric load - EVA TEST.Rock compressive strength and rock tensile strength of T 2y 5 marble are – and – MPa respectively.

Thus the brittleness index, n b, of T 2 y 5 marble is between and Similarly the brittleness index, B, of T 2 y 5 marble also can be determined, in which E .